Harmony Biosciences Holdings Inc.

02/25/2025 | Press release | Distributed by Public on 02/25/2025 18:49

Automatic Shelf Registration Statement (Form S-3ASR)

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As filed with the Securities and Exchange Commission on February 25, 2025
Registration No. 333-      ​
UNITED STATES
SECURITIES AND EXCHANGE COMMISSION
WASHINGTON, DC 20549​
FORM S-3
REGISTRATION STATEMENT
UNDER
THE SECURITIES ACT OF 1933
Harmony Biosciences Holdings, Inc.
(Exact name of registrant as specified in its charter)
Delaware
(State or Other Jurisdiction of
Incorporation or Organization)
82-2279923
(I.R.S. Employer
Identification Number)
630 W. Germantown Pike, Suite 215
Plymouth Meeting, PA 19462
(484) 539-9800
(Address, including zip code, and telephone number, including area code, of registrant's principal executive offices)
Jeffrey M. Dayno
President, Chief Executive Officer and Director
630 W. Germantown Pike, Suite 215
Plymouth Meeting, PA 19462
(484) 539-9800
(Name, address, including zip code, and telephone number, including area code, of agent for service)
Copies to:
Christopher D. Lueking, Esq.
Jonathan E. Sarna, Esq.
Latham & Watkins LLP
330 North Wabash Avenue, Suite 2800
Chicago, IL 60611
(312) 867-7700
(Approximate date of commencement of proposed sale to the public: From time to time after the effective date of this registration statement.)
If the only securities being registered on this Form are being offered pursuant to dividend or interest reinvestment plans, please check the following box. ☐
If any of the securities being registered on this Form are to be offered on a delayed or continuous basis pursuant to Rule 415 under the Securities Act of 1933, other than securities offered only in connection with dividend or interest reinvestment plans, check the following box. ☒
If this Form is filed to register additional securities for an offering pursuant to Rule 462(b) under the Securities Act, please check the following box and list the Securities Act registration statement number of the earlier effective registration statement for the same offering. ☐
If this Form is a post-effective amendment filed pursuant to Rule 462(c) under the Securities Act, check the following box and list the Securities Act registration statement number of the earlier effective registration statement for the same offering. ☐
If this Form is a registration statement pursuant to General Instruction I.D. or a post-effective amendment thereto that shall become effective upon filing with the Commission pursuant to Rule 462(e) under the Securities Act, check the following box. ☒
If this Form is a post-effective amendment to a registration statement filed pursuant to General Instruction I.D. filed to register additional securities or additional classes of securities pursuant to Rule 413(b) under the Securities Act, check the following box. ☐
Indicate by check mark whether the registrant is a large accelerated filer, an accelerated filer, a non-accelerated filer, a smaller reporting company, or an emerging growth company. See the definitions of "large accelerated filer," "accelerated filer," "smaller reporting company" and "emerging growth company" in Rule 12b-2 of the Exchange Act.
Large accelerated filer ☒
Accelerated filer ☐
Non-accelerated filer ☐
Smaller reporting company
Emerging growth company
If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 7(a)(2)(B) of Securities Act. ☐
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EXPLANATORY NOTE
This registration statement contains:

a base prospectus which covers the offering, issuance and sale from time to time by the registrant of the registrant's common stock, preferred stock, debt securities, warrants, depositary shares, rights and/or units; and

a sales agreement prospectus supplement covering the offering, issuance and sale by the registrant of up to a maximum aggregate offering price of $200,000,000 of the registrant's common stock that may be issued and sold from time to time under the sales agreement, dated February 25, 2025 with Leerink Partners LLC and Cantor Fitzgerald & Co. as agents.
The base prospectus immediately follows this explanatory note. The specific terms of any securities to be offered pursuant to the base prospectus will be specified in one or more prospectus supplement(s) to the base prospectus. The sales agreement prospectus supplement immediately follows the base prospectus. The $200,000,000 of common stock that may be offered, issued and sold under the sales agreement prospectus supplement is included in the securities that may be offered, issued and sold by the registrant under the base prospectus.

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PROSPECTUS
HARMONY BIOSCIENCES HOLDINGS, INC.
DEBT SECURITIES
COMMON STOCK
PREFERRED STOCK
WARRANTS
DEPOSITARY SHARES
RIGHTS
UNITS
We may from time to time offer to sell our debt securities, common stock or preferred stock, either separately or represented by warrants, depositary shares or rights, as well as units that include any of these securities or securities of other entities. The debt securities may consist of debentures, notes or other types of debt. Our common stock is listed on the Nasdaq Global Market and trades under the ticker symbol "HRMY." The debt securities, preferred stock, warrants and rights may be convertible or exercisable or exchangeable for common or preferred stock or other securities of ours or debt or equity securities of one or more other entities.
We may offer and sell these securities to or through one or more underwriters, dealers and agents, or directly to purchasers, on a continuous or delayed basis. These securities also may be resold by security holders. We will provide specific terms of any securities to be offered in supplements to this prospectus. You should read this prospectus and the applicable prospectus supplement carefully before you invest in our securities.
Our principal executive offices are located at 630 W. Germantown Pike, Suite 215, Plymouth Meeting, PA 19462. Our telephone number is (484) 539-9800.
Investing in our securities involves certain risks. See the "Risk Factors" section of our filings with the Securities and Exchange Commission as well as the risk factors and other information contained in the applicable prospectus supplement, any related free writing prospectus and in the documents we incorporate by reference into this prospectus or any applicable prospectus supplement. See "Where You Can Find More Information."
NEITHER THE SECURITIES AND EXCHANGE COMMISSION NOR ANY STATE SECURITIES COMMISSION HAS APPROVED OR DISAPPROVED OF THESE SECURITIES OR DETERMINED IF THIS PROSPECTUS IS TRUTHFUL OR COMPLETE. ANY REPRESENTATION TO THE CONTRARY IS A CRIMINAL OFFENSE.
The date of this prospectus is February 25, 2025.
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Page
WHERE YOU CAN FIND MORE INFORMATION
1
ABOUT THE COMPANY
1
INCORPORATION BY REFERENCE
2
USE OF PROCEEDS
3
DESCRIPTION OF SECURITIES
3
PLAN OF DISTRIBUTION
3
SELLING SECURITYHOLDERS
3
VALIDITY OF THE SECURITIES
3
EXPERTS
4

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WHERE YOU CAN FIND MORE INFORMATION
We have filed with the Securities and Exchange Commission (the "SEC"), a registration statement on Form S-3 with respect to the securities offered hereby. This prospectus does not contain all the information set forth in the registration statement, parts of which are omitted in accordance with the rules and regulations of the SEC. For further information with respect to us and the securities offered hereby, reference is made to the registration statement.
Statements contained in this prospectus, any prospectus supplement and any free writing prospectus that we have authorized, or that are incorporated by reference into this prospectus or any prospectus supplement, about the provisions or contents of any agreement or other document are not necessarily complete. If SEC rules and regulations require that any agreement or document be filed as an exhibit to the registration statement and we file the agreement or document, you should refer to that agreement or document for a complete description of these matters.
We file annual, quarterly and current reports, proxy statements and other information with the SEC. We also make our annual, quarterly and current reports, proxy statements and other information available free of charge on our investor relations website, https://ir.harmonybiosciences.com, as soon as reasonably practicable after we electronically file these materials with, or furnish them to, the SEC. We use our website as a channel of distribution for material company information. Important information, including financial information, analyst presentations, financial news releases, and other material information about us is routinely posted on and accessible at https://ir. harmonybiosciences.com. Additionally, the SEC maintains a website that contains reports, proxy and information statements and other information regarding issuers, including us, that are filed electronically with the SEC, accessible at http://www.sec.gov.
Unless otherwise indicated or the context otherwise requires, references in this prospectus to the "registrant," "we," "us," and "our" refer to Harmony Biosciences Holdings, Inc. and its subsidiaries.
ABOUT THE COMPANY
We are a commercial-stage pharmaceutical company dedicated to developing and commercializing innovative therapies for people living with rare neurological disorders who have unmet medical needs. Established by founder Paragon Biosciences LLC, our mission is to positively impact the lives of those living with rare diseases who are so often underserved.

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INCORPORATION BY REFERENCE
The SEC allows us to "incorporate by reference" information into this prospectus, which means that we can disclose important information to you by referring to those documents. We hereby "incorporate by reference" the documents listed below. The information that we file later with the SEC will automatically update and in some cases supersede this information. Specifically, we incorporate by reference the following documents or information filed with the SEC (other than, in each case, documents or information deemed to have been furnished and not filed in accordance with SEC rules):



The description of our common stock, par value $0.00001 per share, contained in the Registration Statement on Form 8-A, filed with the SEC on August 14, 2020 (File No. 001-39450), registering our common stock pursuant to Section 12(b) of the Securities Exchange Act of 1934, as amended (the "Exchange Act"), as updated by Exhibit 4.3 to our Annual Report on Form 10-K for the year ended December 31, 2020 (File No. 001-39450), including any and all amendments and reports filed under Section 13(a) or 15(d) of the Exchange Act for the purpose of updating such description; and

Future filings we make with the SEC under Sections 13(a), 13(c), 14 or 15(d) of the Exchange Act after the date of this prospectus and before the termination of this offering; provided, however, that we are not incorporating by reference any documents or information, including parts of documents that we file with the SEC, that are deemed to be furnished and not filed with the SEC. Unless specifically stated to the contrary, none of the information we disclose under Items 2.02 or 7.01 of any Current Report on Form 8-K that we may from time to time furnish to the SEC will be incorporated by reference into, or otherwise included in, this prospectus.
We will provide, without charge, to each person to whom a copy of this prospectus has been delivered, including any beneficial owner, a copy of any and all of the documents referred to herein that are summarized and incorporated by reference in this prospectus, if such person makes a written or oral request directed to:
Harmony Biosciences Holdings, Inc.
ATTN: Corporate Secretary
630 W. Germantown Pike, Suite 215
Plymouth Meeting, PA 19462
(484) 539-9800
You should rely only on the information incorporated by reference or provided in this prospectus and any applicable prospectus supplement. We have not authorized anyone else to provide you with other information.

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USE OF PROCEEDS
We will set forth in the applicable prospectus supplement our intended use for the net proceeds received by us for our sale of securities under this prospectus. We will not receive the net proceeds of any sales by selling security holders. Unless otherwise stated in the applicable prospectus supplement, we will use the proceeds of any offering for general corporate purposes, which may include repayment of debt, acquisitions, additions to working capital and capital expenditures.
DESCRIPTION OF SECURITIES
We will set forth in the applicable prospectus supplement a description of the debt securities, common stock, preferred stock, warrants, depositary shares, rights or units that may be offered under this prospectus.
Any debt securities offered under this prospectus will be governed by a debt indenture. The form of indenture has been filed as an exhibit hereto.
PLAN OF DISTRIBUTION
We will set forth in the applicable prospectus supplement a description of the plan of distribution for the securities to be offered under the supplement. We may offer and sell these securities to or through one or more underwriters, dealers and agents, or directly to purchasers, on a continuous or delayed basis.
SELLING SECURITYHOLDERS
We will set forth information about selling securityholders, where applicable, in a prospectus supplement, in a post-effective amendment, or in filings we make with the SEC under the Exchange Act that are incorporated by reference.
VALIDITY OF THE SECURITIES
Latham & Watkins LLP will pass upon the validity of any securities issued under this prospectus. Any underwriters will be represented by their own legal counsel.

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EXPERTS
The consolidated financial statements of Harmony Biosciences Holdings, Inc. appearing in the registrant's Annual Report on Form 10-K for the year ended December 31, 2024, and the effectiveness of the registrant's internal control over financial reporting as of December 31, 2024, have been audited by Deloitte & Touche LLP, independent registered public accounting firm, as set forth in their reports thereon, included therein, and incorporated herein by reference. Such consolidated financial statements are incorporated herein by reference in reliance upon the reports of such reports given on the authority of such firm as experts in accounting and auditing.

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PROSPECTUS SUPPLEMENT
Up to $200,000,000
Common Stock
We have entered into a Sales Agreement, dated as of February 25, 2025 (the "Sales Agreement"), with Leerink Partners LLC and Cantor Fitzgerald & Co. (collectively, the "Sales Agents") relating to the offering of shares of our common stock, $0.00001 par value per share, having an aggregate gross sales price of up to $200,000,000, from time to time through the Sales Agents.
Sales of shares of our common stock under this prospectus, if any, may be made by any method deemed to be an "at the market offering" as defined in Rule 415(a)(4) promulgated under the Securities Act of 1933, as amended, or the Securities Act. The Sales Agents are not required to sell any specific number or dollar amount of shares of our common stock. Each of the Sales Agents has agreed to use its commercially reasonable efforts to sell on our behalf all of the shares of common stock requested to be sold by us, consistent with its normal trading and sales practices, on mutually agreed terms among the Sales Agents and us. There is no arrangement for funds to be received in any escrow, trust or similar arrangement.
The Sales Agents will be entitled to compensation under the terms of the Sales Agreement at a commission rate of up to 3.0% of the gross sales price per share sold. In connection with the sale of common stock on our behalf, each of the Sales Agents will be deemed to be an "underwriter" within the meaning of the Securities Act, and the compensation of the Sales Agents will be deemed to be underwriting commissions or discounts. We have agreed to provide indemnification and contribution to the Sales Agents with respect to certain liabilities, including liabilities under the Securities Act.
The net proceeds from any sales under this prospectus will be used as described under the section entitled "Use of Proceeds." See "Plan of Distribution" for additional information regarding compensation to be paid to the Sales Agents. The proceeds we receive from sales of our common stock, if any, will depend on the number of shares actually sold and the offering price of such shares. Our common stock is listed on the Nasdaq Global Market ("Nasdaq") under the trading symbol "HRMY." The last reported sale price of our common stock on Nasdaq on February 24, 2025 was $34.18 per share.
Investing in our common stock involves risks. See the information under the caption "Risk Factors" on page S-4 of this prospectus supplement, in our most recent Annual Report on Form 10-K and our subsequent Quarterly Reports on Form 10-Q, which are incorporated by reference herein, for factors you should consider before investing in our common stock.
Neither the Securities and Exchange Commission, nor any state securities commission has approved or disapproved of these securities or determined if this prospectus supplement or the accompanying prospectus is truthful or complete. Any representation to the contrary is a criminal offense.
Leerink Partners
Cantor
The date of this prospectus supplement is February 25, 2025
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Neither we nor any of the Sales Agents have authorized any person to give you any information or to make any representations in connection with the offering to which this prospectus supplement and the accompanying prospectus relate other than those contained in or incorporated by reference in this prospectus supplement, the accompanying prospectus or any applicable free writing prospectus prepared by us. If given or made, any such information or representations must not be relied upon as having been so authorized. We are not, and the Sales Agents are not, making an offer to sell these securities in any jurisdiction where the offer or sale is not permitted. You should assume that the information appearing in this prospectus supplement, the accompanying prospectus, any free writing prospectus prepared by us and in the documents incorporated by reference in this prospectus supplement and the accompanying prospectus is accurate only as of the respective dates of such documents or as of the date or dates which are specified therein. Our business, financial condition, liquidity, results of operations and prospects may have changed since those dates.

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Prospectus Supplement
Page
ABOUT THIS PROSPECTUS SUPPLEMENT
S-ii
CAUTIONARY STATEMENT REGARDING FORWARD-LOOKING STATEMENTS
S-iii
PROSPECTUS SUPPLEMENT SUMMARY
S-1
RISK FACTORS
S-4
USE OF PROCEEDS
S-6
DILUTION.
S-7
MATERIAL U.S. FEDERAL INCOME TAX CONSEQUENCES TO NON-U.S. HOLDERS
S-8
PLAN OF DISTRIBUTION
S-12
LEGAL MATTERS
S-13
EXPERTS
S-13
WHERE YOU CAN FIND MORE INFORMATION; INCORPORATION OF CERTAIN INFORMATION BY REFERENCE
S-14

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ABOUT THIS PROSPECTUS SUPPLEMENT
This prospectus supplement is part of a registration statement on Form S-3 that we have filed with the U.S. Securities and Exchange Commission, or the SEC, utilizing a "shelf" registration process. By using a shelf registration statement, we may offer shares of our common stock having an aggregate offering price of up to $200,000,000 from time to time under this prospectus supplement at prices and on terms to be determined by market conditions at the time of offering.
We provide information to you about this offering of our common stock in two separate documents that are bound together: (1) this prospectus supplement, which describes the specific details regarding this offering; and (2) the accompanying base prospectus, which provides general information, some of which may not apply to this offering. Generally, when we refer to this "prospectus supplement," we are referring to both documents combined. If information in this prospectus supplement is inconsistent with the accompanying base prospectus, you should rely on this prospectus supplement. To the extent there is a conflict between the information contained in this prospectus supplement, on the one hand, and the information contained in any document incorporated by reference in this prospectus supplement, on the other hand, you should rely on the information in this prospectus supplement. If any statement in one of these documents is inconsistent with a statement in another document having a later date-for example, a document incorporated by reference in this prospectus supplement-the statement in the document having the later date modifies or supersedes the earlier statement.
This prospectus supplement does not contain all of the information that is important to you. You should read this prospectus supplement together with the accompanying prospectus, all free writing prospectuses, if any, that we have authorized for use in connection with this offering and all documents incorporated by reference. You should read this prospectus supplement, the accompanying prospectus and any free writing prospectus to which we have referred you and the documents incorporated by reference herein described under "Where You Can Find More Information; Incorporation of Certain Information by Reference" in this prospectus supplement before deciding whether to invest in the shares of common stock offered by this prospectus supplement. References to documents or information incorporated by reference in this prospectus supplement or the accompanying prospectus include documents or information deemed to be incorporated by reference herein or therein. The documents incorporated by reference in this prospectus supplement are identified under the caption "Incorporation of Certain Documents by Reference" in this prospectus supplement.

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CAUTIONARY STATEMENT REGARDING FORWARD-LOOKING STATEMENTS
This prospectus supplement and the accompanying prospectus, including the information we incorporate by reference herein, contain "forward-looking statements" within the meaning of Section 27A of the Securities Act and Section 21E of the Securities Exchange Act of 1934, as amended (the "Exchange Act"). These statements include statements about our plans, strategies, financial performance, prospects or future events and involve known and unknown risks that are difficult to predict. As a result, our actual results, performance or achievements may differ materially from those expressed or implied by these forward-looking statements. In some cases, you can identify forward-looking statements by the use of words such as "will," "may," "expect," "would," "could," "might," "intend," "plan," "believe," "estimate," "anticipate," "deliver," "seek," "aim," "potential," "target," "outlook," and variations of these terms and similar expressions, or the negative of these terms or similar expressions. Such forward-looking statements are necessarily based upon estimates and assumptions that, while considered reasonable by us and our management, are inherently uncertain. Factors that may cause actual results to differ materially from current expectations include, but are not limited to:

the factors discussed in our Annual Report on Form 10-K for the fiscal year ended December 31, 2024 under the sections titled "Risk Factors" in Part I, Item 1A and "Management's Discussion and Analysis of Financial Condition and Results of Operations" in Part II, Item 7;

our commercialization efforts and strategy for WAKIX;

the rate and degree of market acceptance and clinical utility of pitolisant in additional indications, if approved, and any other product candidates we may develop or acquire, if approved;

our research and development plans, including our plans to explore the therapeutic potential of pitolisant in additional indications, progress developing the new formulations Pitolisant Gastro-resistant and Pitolisant High Dose, and the development of ZYN002, EPX100 and other compounds;

our ongoing and planned clinical trials;

the availability of favorable insurance coverage and reimbursement for WAKIX;

the timing of, and our ability to obtain, regulatory approvals for pitolisant for other indications as well as any other product candidates;

our estimates regarding expenses, future revenue, capital requirements and additional financing needs;

our ability to identify, acquire and integrate additional products or product candidates with significant commercial potential that are consistent with our commercial objectives;

our commercialization, marketing and manufacturing capabilities and strategy;

significant competition in our industry;

our intellectual property position;

loss or retirement of key members of management;

failure to successfully execute our growth strategy, including any delays in our planned future growth;

our failure to maintain effective internal controls;

the impact of government laws and regulations; and

the use of proceeds from this offering.
These factors and the other risk factors described or incorporated by reference in this prospectus supplement and the accompanying prospectus are not necessarily all of the important factors that could cause our actual results, performance or achievements to differ materially from those expressed in or implied by any forward-looking statements. Other unknown or unpredictable factors also could harm our business, financial condition, results of operations or cash flows.

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All forward-looking statements attributable to us or persons acting on our behalf are expressly qualified in their entirety by the cautionary statements set forth above. Forward-looking statements speak only as of the date they are made, and we do not undertake or assume, and we hereby disclaim, any obligation to update publicly any of these forward-looking statements to reflect actual results, new information, future events, changes in assumptions or changes in other factors affecting forward-looking statements, except to the extent required by applicable law. If we update one or more forward-looking statements, no inference should be drawn that we will make additional updates with respect to those or other forward-looking statements.

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PROSPECTUS SUPPLEMENT SUMMARY
This summary highlights some of the information in this prospectus supplement, the accompanying prospectus and the documents incorporated by reference. It does not contain all of the information that you should consider before making a decision to invest in shares of our common stock. You should read carefully the more detailed information in this prospectus supplement and the accompanying prospectus, and the information incorporated by reference into this prospectus supplement and the accompanying prospectus. Unless the context requires otherwise, references in this prospectus supplement and the accompanying prospectus to the "we," "our," "us," "our company" and "Harmony" are to Harmony Biosciences Holdings, Inc., a Delaware corporation, together with its consolidated subsidiaries.
Overview
At Harmony, we are cultivating a differentiated neuroscience company, rooted in innovation and driven by a commitment to addressing the unmet needs of patients living with neurological diseases. To date, we have focused on rare neurological diseases with a growing portfolio now spanning sleep/wake, neurobehavioral, and rare epilepsy, and we are harnessing scientific insights and pioneering approaches to advance meaningful treatments that help patients thrive.
Our lead product, WAKIX® (pitolisant) ("WAKIX"), is a first-in-class therapy with a novel mechanism of action designed to enhance histamine signaling in the brain by binding to H3 receptors. Since its initial FDA approval in 2019 for excessive daytime sleepiness ("EDS") in adult patients with narcolepsy and subsequent approvals for cataplexy in adult patients in 2020 and EDS in pediatric patients six years and older in 2024, WAKIX has continued to reshape the treatment landscape and remains the only approved treatment for narcolepsy that is not scheduled as a controlled substance by the U.S. Drug Enforcement Administration.
Beyond narcolepsy, we have taken a mechanistic-based approach to expanding the reach of pitolisant, identifying idiopathic hypersomnia ("IH") as a potential next indication in its lifecycle. In the fourth quarter of 2024, we submitted a supplemental New Drug Application for pitolisant in IH based on a comprehensive evaluation of data from our INTUNE study and additional sources. In February 2024, we received a Refusal to File letter from the FDA for pitolisant in IH. We are also advancing late-stage clinical programs exploring pitolisant in Prader-Willi syndrome and myotonic dystrophy type 1 and continue to grow our impact in other rare neurological diseases. In July 2022, we entered into the 2022 LCA with Bioprojet whereby we obtained exclusive rights to manufacture, develop and commercialize one or more next generation pitolisant-based products in the United States and Latin America. Two of the next generation formulations, pitolisant Gastro-Resistant and pitolisant High-Dose, are currently in clinical development.
Along with nurturing the growth of our original pipeline, our innovation strategy includes targeted business development that strengthens our foundation and strategically extends our patient reach as we look to expand our portfolio to new diseases beyond histaminergic science. In October 2023, we acquired Zynerba Pharmaceuticals, Inc. ("Zynerba"), adding global rights to develop, manufacture and commercialize ZYN-002, a pharmaceutically manufactured 100% synthetic, patent protected permeation enhanced cannabidiol gel, to our neurobehavioral franchise. With a pivotal Phase 3 trial underway for Fragile X syndrome and plans to initiate a Phase 3 registrational study in 22q deletion syndrome in 2025, we are poised to deliver new treatment possibilities for patients with neurobehavioral conditions.
In April 2024, we expanded into orexin science through a sublicense agreement with Bioprojet for an orexin 2 receptor agonist ("BP1.15205") in preclinical development for narcolepsy and other potential indications. Under the sublicense agreement we obtained the exclusive right to develop, manufacture and commercialize BP1.15205 in the United States and Latin American territories, which are rights originally licensed from Teijin Pharma, the innovator of BP1.15205. We further broadened our portfolio into rare epilepsy with the acquisition of Epygenix Therapeutics, Inc., adding global rights to develop, manufacture and commercialize EPX-100, a serotonin (5HT-2) receptor agonist, and EPX-200, a selective 5HT-2C agonist. EPX-100 is in Phase 3 registrational trials for Dravet Syndrome and Lennox-Gastaut Syndrome, and EPX-200 is in the pre-IND phase for developmental and epileptic encephalopathies.
Our innovative portfolio of assets reflects our dedication to novel science, innovative therapies and excellence in delivering these treatments to patients with serious medical conditions who have few or no available options.

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Our operations are conducted by our wholly owned subsidiaries, Harmony Biosciences, LLC and Harmony Biosciences Management, Inc., formerly known as Zynerba prior to July 1, 2024.
Corporate Information
Our principal executive offices are located at 630 W. Germantown Pike, Plymouth Meeting, PA 19462, and our telephone number is (484) 539-9800. Our internet website is www.harmonybiosciences.com. We make important information available on our website free of charge, including copies of our Annual Reports on Form 10-K, Quarterly Reports on Form 10-Q, Current Reports on Form 8-K and amendments to those reports filed or furnished pursuant to Section 13(a) or 15(d) of the Exchange Act, as soon as reasonably practicable after such reports are electronically filed with, or furnished to, the SEC. We recognize our website as a key channel of distribution to reach public investors and as a means of disclosing material non-public information to comply with our disclosure obligations under Regulation FD. Information contained on our website shall not be deemed incorporated into, or to be part of this prospectus supplement, and any website references are not intended to be made through active hyperlinks. See "Where You Can Find More Information; Incorporation by Reference" beginning on page S-14 of this prospectus supplement and on page 2 of the accompanying prospectus.

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THE OFFERING
Issuer
Harmony Biosciences Holdings, Inc.
Common Stock Offered By Us
Shares of common stock, par value $0.00001 per share, having aggregate sales proceeds of up to $200,000,000.
Plan of Distribution
We will sell the shares of our common stock offered hereby by any method permitted that is deemed an "at the market offering" as defined in Rule 415(a)(4) under the Securities Act, through the Sales Agents. See the section entitled "Plan of Distribution" on page S-12 of this prospectus supplement.
Use of Proceeds
We currently intend to use the net proceeds from this offering for general corporate purposes, which may include repaying or repurchasing indebtedness (including amounts outstanding from time to time under our credit agreements), working capital and capital expenditures, and potential future investments. See "Use of Proceeds" in this prospectus supplement.
Listing and Trading Symbol
Shares of our common stock are traded on Nasdaq under the symbol "HRMY."
Risk Factors
Investing in our common stock involves a high degree of risk. You should carefully read and consider the information set forth under the heading "Risk Factors" beginning on page S-4 of this prospectus supplement and other risk factors incorporated by reference into this prospectus supplement and the accompanying prospectus from the filings we make with the SEC, as well as all other information included or incorporated by reference in this prospectus supplement and the accompanying prospectus, before deciding to invest in our common stock.

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RISK FACTORS
Investing in shares of our common stock involves risks. Before you invest in shares of our common stock, you should carefully consider the risk factors described below, as well as the risk factors described in our most recent Annual Report on Form 10-K and in our subsequent Quarterly Reports on Form 10-Q, which are incorporated by reference into this prospectus supplement and the accompanying prospectus. You should also carefully consider all of the other information included and incorporated by reference in this prospectus supplement and the accompanying prospectus. If any of the risks discussed or incorporated by reference in this prospectus supplement or the accompanying prospectus were to occur, our business, financial condition, liquidity, results of operations and prospects, and our ability to service our debt and make distributions to our stockholders could be materially and adversely affected, the market price of shares of our common stock could decline significantly and you could lose all or part of your investment in our shares of common stock. The risks described herein and those incorporated by reference into this prospectus supplement and the accompanying prospectus are not the only ones facing us. Additional risks not presently known to us or which we currently consider immaterial also may adversely affect us.
If you purchase our common stock sold in this offering, you may experience immediate and substantial dilution in the net tangible book value of your common stock. In addition, we may issue additional equity or convertible debt securities in the future, which may result in additional dilution to you.
The price per share of our common stock being offered may be higher than the net tangible book value per share of our outstanding common stock prior to this offering. Assuming that an aggregate of 5,787,037 shares of common stock are sold at a price of $346.56 per share, the last reported sale price of our common stock on Nasdaq on February 21, 2025, for aggregate gross proceeds of approximately $200.0 million, and after deducting commissions and estimated offering expenses payable by us, new investors in this offering would incur immediate dilution of $11.75 per share. For a more detailed discussion of the foregoing, see the section entitled "Dilution" below.
Investors in this offering may experience future dilution.
In order to raise additional capital, we may in the future offer additional shares of our common stock or other securities convertible into, or exchangeable for, our common stock at prices that may not be the same as the price per share in this offering. We cannot assure you that we will be able to sell shares of our common stock or other related securities in any other offering at a price per share that is equal to or greater than the price per share paid by investors in this offering. If the price per share at which we sell additional shares of our common stock or related securities in future transactions is less than the price per share in this offering, investors who purchase our common stock in this offering will suffer dilution in their investment.
In addition, we have a significant number of stock options for shares of our common stock outstanding. To the extent that outstanding stock options have been or may be exercised, investors purchasing our common stock in this offering may experience further dilution in the future. Furthermore, a significant portion of our total outstanding shares are eligible to be sold into the market, which could cause the market price of our common stock to drop significantly, even if our business is doing well.
In addition, to the extent we raise additional capital in the future and we issue additional shares of common stock or securities convertible or exchangeable for our common stock, our then existing stockholders may experience dilution and the new securities may have rights senior to those of our common stock offered in this offering.
Our management team may invest or spend the proceeds of this offering in ways with which you may not agree or in ways which may not yield a significant return.
Our management will have broad discretion over the use of proceeds from this offering. We intend to use the net proceeds, if any, from this offering for general corporate purposes, which may include repaying or repurchasing indebtedness, working capital and capital expenditures, and potential future investments. Our management will have considerable discretion in the application of the net proceeds, and you will not have the opportunity, as part of your investment decision, to assess whether the proceeds are being used

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appropriately. The net proceeds may be used for corporate purposes that do not increase our operating results or enhance the value of our common stock.
The actual number of shares of common stock we will issue under the Sales Agreement, at any one time or in total, is uncertain.
Subject to certain limitations in the Sales Agreement and compliance with applicable law, we have the discretion to deliver a placement notice to the Sales Agents at any time throughout the term of the Sales Agreement. The per share price of the shares of common stock that are sold by the Sales Agents after delivering a placement notice will fluctuate based on the market price of our common stock during the sales period and limits we set with the Sales Agents. Because the price per share of each share of common stock sold will fluctuate based on the market price of our common stock during the sales period, it is not possible at this stage to predict the number of shares of common stock that will be ultimately issued.
The common stock offered hereby will be sold in "at the market offerings," and investors who buy shares at different times will likely pay different prices.
Investors who purchase shares in this offering at different times will likely pay different prices, and so may experience different outcomes in their investment results. We will have discretion, subject to market demand, to vary the timing, prices, and numbers of shares sold, and there is no minimum or maximum sales price. Investors may experience a decline in the value of their shares as a result of share sales made at prices lower than the prices they paid.

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USE OF PROCEEDS
We may issue and sell shares of our common stock having aggregate sales proceeds of up to $200.0 million from time to time. Because there is no minimum offering amount required as a condition to close this offering, the actual total public offering amount, commissions and proceeds to us, if any, are not determinable at this time. There can be no assurance that we will sell any shares under or fully utilize the Sales Agreement as a source of financing.
We currently intend to use the net proceeds from this offering for general corporate purposes, which may include repaying or repurchasing indebtedness (including amounts outstanding from time to time under our credit agreements), working capital and capital expenditures, and potential future investments.

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DILUTION
If you invest in our common stock in this offering, your ownership interest will be diluted immediately to the extent of the difference between the public offering price per share you will pay in this offering and the as adjusted net tangible book value per share of our common stock after this offering.
Our historical net tangible book value as of December 31, 2024 was $545.9 million, or $9.55 per share of common stock. Historical net tangible book value per share represents the amount of our total tangible assets less total liabilities, divided by the 57,144,887 shares of our common stock outstanding on December 31, 2024.
After giving effect to the issuance and sale of our common stock in the aggregate amount of $200.0 million in this offering at an assumed offering price of $34.56 per share, the last reported sale price of our common stock on Nasdaq on February 21, 2025, and after deducting commissions and estimated aggregate offering expenses payable by us, our as adjusted net tangible book value as of December 31, 2024 would have been $739.5 million, or $11.75 per share. This represents an immediate increase in as adjusted net tangible book value of $2.20 per share to existing stockholders and immediate dilution in as adjusted net tangible book value of $22.81 per share to new investors purchasing common stock in this offering. Dilution per share to new investors is determined by subtracting the as adjusted net tangible book value per share after this offering from the assumed public offering price of $34.56 per share. The following table illustrates this per share dilution to the new investors purchasing shares of our common stock in this offering:
Assumed public offering price per share
$ 34.56
Historical net tangible book value per share as of December 31, 2024
$ 9.55
Increase in as adjusted net tangible book value per share attributable to this offering
2.20
As adjusted net tangible book value per share after this offering
11.75
Dilution per share to new investors in this offering
$ 22.81
The information discussed above is based on 57,144,887 shares of our common stock outstanding as of December 31, 2024, and excludes:

7,157,235 shares of our common stock issuable upon the exercise of stock options outstanding as of December 31, 2024, at a weighted average exercise price of $32.48 per share;

638,900 shares of our common stock issuable upon the vesting and settlement of restricted stock units ("RSUs") outstanding as of December 31, 2024;

1,440,150 shares of our common stock issuable upon the exercise of outstanding stock options or vesting and settlement of RSUs granted after December 31, 2024; and

6,888,336 shares of our common stock reserved for future issuance under our 2020 Employee Stock Purchase Plan, 2020 Incentive Award Plan, as amended, and Non-Employee Director Compensation Program as of December 31, 2024.
To the extent that outstanding stock options are exercised or we issue additional stock options, restricted stock units, warrants or shares of our common stock in the future, there will be further dilution to investors purchasing common stock in this offering. In addition, we may choose to raise additional capital due to market conditions or strategic considerations even if we believe we have sufficient funds for our current or future operating plans. To the extent that additional capital is raised through the sale of equity or convertible debt securities, the issuance of these securities could result in further dilution to our stockholders.

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MATERIAL U.S. FEDERAL INCOME TAX CONSEQUENCES TO NON-U.S. HOLDERS
The following discussion is a summary of the material U.S. federal income tax consequences to Non-U.S. Holders (as defined below) of the purchase, ownership, and disposition of our common stock issued pursuant to this offering, but does not purport to be a complete analysis of all potential tax effects. The effects of other U.S. federal tax laws, such as estate and gift tax laws, and any applicable state, local, or non-U.S. tax laws are not discussed. This discussion is based on the U.S. Internal Revenue Code of 1986, as amended (the "Code"), Treasury Regulations promulgated thereunder, judicial decisions, and published rulings and administrative pronouncements of the U.S. Internal Revenue Service (the "IRS"), in each case in effect as of the date hereof. These authorities may change or be subject to differing interpretations. Any such change or differing interpretation may be applied retroactively in a manner that could adversely affect a Non-U.S. Holder. We have not sought and will not seek any rulings from the IRS regarding the matters discussed below. There can be no assurance the IRS or a court will not take a contrary position to that discussed below regarding the tax consequences of the purchase, ownership, and disposition of our common stock.
This discussion is limited to Non-U.S. Holders that hold our common stock as a "capital asset" within the meaning of Section 1221 of the Code (generally, property held for investment). This discussion does not address all U.S. federal income tax consequences relevant to a Non-U.S. Holder's particular circumstances, including the impact of the Medicare contribution tax on net investment income and any alternative minimum tax. In addition, it does not address consequences relevant to Non-U.S. Holders subject to special rules, including, without limitation:

U.S. expatriates and former citizens or long-term residents of the United States;

persons holding our common stock as part of a hedge, straddle, or other risk reduction strategy or as part of a conversion transaction or other integrated investment;

banks, insurance companies, and other financial institutions;

brokers, dealers, or traders in securities;

"controlled foreign corporations," "passive foreign investment companies," and corporations that accumulate earnings to avoid U.S. federal income tax;

partnerships or other entities or arrangements treated as partnerships for U.S. federal income tax purposes (and investors therein);

tax-exempt organizations or governmental organizations;

persons deemed to sell our common stock under the constructive sale provisions of the Code;

persons who hold or receive our common stock pursuant to the exercise of any employee stock option or otherwise as compensation;

tax-qualified retirement plans; and

"qualified foreign pension funds" as defined in Section 897(l)(2) of the Code and entities all of the interests of which are held by qualified foreign pension funds.
If a partnership or an entity treated as a partnership for U.S. federal income tax purposes holds our common stock, the tax treatment of a partner in the partnership will depend on the status of the partner, the activities of the partnership, and certain determinations made at the partner level. Accordingly, partnerships holding our common stock and the partners in such partnerships should consult their tax advisors regarding the U.S. federal income tax consequences to them.
THIS DISCUSSION IS FOR INFORMATIONAL PURPOSES ONLY AND IS NOT TAX ADVICE. INVESTORS SHOULD CONSULT THEIR TAX ADVISORS WITH RESPECT TO THE APPLICATION OF THE U.S. FEDERAL INCOME TAX LAWS TO THEIR PARTICULAR SITUATIONS AS WELL AS ANY TAX CONSEQUENCES OF THE PURCHASE, OWNERSHIP, AND DISPOSITION OF OUR COMMON STOCK ARISING UNDER THE U.S. FEDERAL ESTATE OR GIFT TAX LAWS OR UNDER THE LAWS OF ANY STATE, LOCAL, OR NON-U.S. TAXING JURISDICTION OR UNDER ANY APPLICABLE INCOME TAX TREATY.

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Definition of a Non-U.S. Holder
For purposes of this discussion, a "Non-U.S. Holder" is any beneficial owner of our common stock that is neither a "U.S. person" nor an entity treated as a partnership for U.S. federal income tax purposes. A U.S. person is any person that, for U.S. federal income tax purposes, is or is treated as any of the following:

an individual who is a citizen or resident of the United States;

a corporation created or organized under the laws of the United States, any state thereof, or the District of Columbia;

an estate, the income of which is subject to U.S. federal income tax regardless of its source; or

a trust that (1) is subject to the primary supervision of a U.S. court and the control of one or more "United States persons" ​(within the meaning of Section 7701(a)(30) of the Code), or (2) has a valid election in effect to be treated as a United States person for U.S. federal income tax purposes.
Distributions
We do not anticipate declaring or paying dividends to holders of our common stock in the foreseeable future. However, if we do make distributions of cash or property on our common stock, such distributions will constitute dividends for U.S. federal income tax purposes to the extent paid from our current or accumulated earnings and profits, as determined under U.S. federal income tax principles. Amounts not treated as dividends for U.S. federal income tax purposes will constitute a return of capital and first be applied against and reduce a Non-U.S. Holder's adjusted tax basis in its common stock, but not below zero. Any excess will be treated as capital gain and will be treated as described below under "- Sale or Other Taxable Disposition."
Subject to the discussion below on effectively connected income, dividends paid to a Non-U.S. Holder will be subject to U.S. federal withholding tax at a rate of 30% of the gross amount of the dividends (or such lower rate specified by an applicable income tax treaty, provided the Non-U.S. Holder furnishes a valid IRS Form W-8BEN or W-8BEN-E (or other applicable documentation) certifying qualification for the lower treaty rate). A Non-U.S. Holder that does not timely furnish the required documentation, but that qualifies for a reduced treaty rate, may obtain a refund of any excess amounts withheld by timely filing an appropriate claim for refund with the IRS. Non-U.S. Holders should consult their tax advisors regarding their entitlement to benefits under any applicable income tax treaty.
If dividends paid to a Non-U.S. Holder are effectively connected with the Non-U.S. Holder's conduct of a trade or business within the United States (and, if required by an applicable income tax treaty, the Non-U.S. Holder maintains a permanent establishment in the United States to which such dividends are attributable), the Non-U.S. Holder will be exempt from the U.S. federal withholding tax described above. To claim the exemption, the Non-U.S. Holder must furnish to the applicable withholding agent a valid IRS Form W-8ECI, certifying that the dividends are effectively connected with the Non-U.S. Holder's conduct of a trade or business within the United States.
Any such effectively connected dividends will be subject to U.S. federal income tax on a net income basis at the regular rates. A Non-U.S. Holder that is a corporation also may be subject to a branch profits tax at a rate of 30% (or such lower rate specified by an applicable income tax treaty) on such effectively connected dividends, as adjusted for certain items. Non-U.S. Holders should consult their tax advisors regarding any applicable tax treaties that may provide for different rules.
Sale or Other Taxable Disposition
A Non-U.S. Holder will not be subject to U.S. federal income tax on any gain realized upon the sale or other taxable disposition of our common stock unless:

the gain is effectively connected with the Non-U.S. Holder's conduct of a trade or business within the United States (and, if required by an applicable income tax treaty, the Non-U.S. Holder maintains a permanent establishment in the United States to which such gain is attributable);

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the Non-U.S. Holder is a nonresident alien individual present in the United States for 183 days or more during the taxable year of the disposition and certain other requirements are met; or

our common stock constitutes a U.S. real property interest ("USRPI") by reason of our status as a U.S. real property holding corporation ("USRPHC") for U.S. federal income tax purposes.
Gain described in the first bullet point above generally will be subject to U.S. federal income tax on a net income basis at the regular rates. A Non-U.S. Holder that is a corporation also may be subject to a branch profits tax at a rate of 30% (or such lower rate specified by an applicable income tax treaty) on such effectively connected gain, as adjusted for certain items.
A Non-U.S. Holder described in the second bullet point above will be subject to U.S. federal income tax at a rate of 30% (or such lower rate specified by an applicable income tax treaty) on gain realized upon the sale or other taxable disposition of our common stock, which may be offset by U.S. source capital losses of the Non-U.S. Holder (even though the individual is not considered a resident of the United States), provided the Non-U.S. Holder has timely filed U.S. federal income tax returns with respect to such losses.
With respect to the third bullet point above, we believe we currently are not, and do not anticipate becoming, a USRPHC. Because the determination of whether we are a USRPHC depends, however, on the fair market value of our USRPIs relative to the fair market value of our non-U.S. real property interests and our other business assets, there can be no assurance we currently are not a USRPHC or will not become one in the future. Even if we are or were to become a USRPHC, gain arising from the sale or other taxable disposition of our common stock by a Non-U.S. Holder will not be subject to U.S. federal income tax if our common stock is "regularly traded," as defined by applicable Treasury Regulations, on an established securities market and such Non-U.S. Holder owned, actually and constructively, 5% or less of our common stock throughout the shorter of the five-year period ending on the date of the sale or other taxable disposition or the Non-U.S. Holder's holding period.
Non-U.S. Holders should consult their tax advisors regarding potentially applicable income tax treaties that may provide for different rules.
Information Reporting and Backup Withholding
Payments of dividends on our common stock will not be subject to backup withholding, provided the applicable withholding agent does not have actual knowledge or reason to know the holder is a United States person and the holder either certifies its non-U.S. status, such as by furnishing a valid IRS Form W-8BEN, W-8BEN-E, or W-8ECI, or otherwise establishes an exemption. However, information returns are required to be filed with the IRS in connection with any distributions on our common stock paid to the Non-U.S. Holder, regardless of whether such distributions constitute dividends or whether any tax was actually withheld. In addition, proceeds of the sale or other taxable disposition of our common stock within the United States or conducted through certain U.S.-related brokers generally will not be subject to backup withholding or information reporting if the applicable withholding agent receives the certification described above and does not have actual knowledge or reason to know that such holder is a United States person or the holder otherwise establishes an exemption. Proceeds of a disposition of our common stock conducted through a non-U.S. office of a non-U.S. broker generally will not be subject to backup withholding or information reporting.
Copies of information returns that are filed with the IRS may also be made available under the provisions of an applicable treaty or agreement to the tax authorities of the country in which the Non-U.S. Holder resides or is established.
Backup withholding is not an additional tax. Any amounts withheld under the backup withholding rules may be allowed as a refund or a credit against a Non-U.S. Holder's U.S. federal income tax liability, provided the required information is timely furnished to the IRS.
Additional Withholding Tax on Payments Made to Foreign Accounts
Withholding taxes may be imposed under Sections 1471 to 1474 of the Code (such Sections commonly referred to as the Foreign Account Tax Compliance Act, or "FATCA") on certain types of payments made

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to non-U.S. financial institutions and certain other non-U.S. entities. Specifically, a 30% withholding tax may be imposed on dividends on, or (subject to the proposed Treasury Regulations discussed below) gross proceeds from the sale or other disposition of, our common stock paid to a "foreign financial institution" or a "non-financial foreign entity" ​(each as defined in the Code), unless (1) the foreign financial institution undertakes certain diligence and reporting obligations, (2) the non-financial foreign entity either certifies it does not have any "substantial United States owners" ​(as defined in the Code) or furnishes identifying information regarding each substantial United States owner, or (3) the foreign financial institution or non-financial foreign entity otherwise qualifies for an exemption from these rules. If the payee is a foreign financial institution and is subject to the diligence and reporting requirements in (1) above, it must enter into an agreement with the U.S. Department of the Treasury requiring, among other things, that it undertake to identify accounts held by certain "specified United States persons" or "United States owned foreign entities" ​(each as defined in the Code), annually report certain information about such accounts, and withhold 30% on certain payments to non-compliant foreign financial institutions and certain other account holders. Foreign financial institutions located in jurisdictions that have an intergovernmental agreement with the United States governing FATCA may be subject to different rules.
Under the applicable Treasury Regulations and administrative guidance, withholding under FATCA generally applies to payments of dividends on our common stock. While withholding under FATCA would have applied also to payments of gross proceeds from the sale or other disposition of stock, proposed Treasury Regulations eliminate FATCA withholding on payments of gross proceeds entirely. Taxpayers generally may rely on these proposed Treasury Regulations until final Treasury Regulations are issued.
Prospective investors should consult their tax advisors regarding the potential application of withholding under FATCA to their investment in our common stock.

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PLAN OF DISTRIBUTION
We have entered into a Sales Agreement with Leerink Partners LLC and Cantor Fitzgerald & Co. (collectively, the "Sales Agents," and each individually, a "Sales Agent"), under which we may issue and sell shares of common stock having an aggregate offering price of up to $200.0 million from time to time through the Sales Agents. Sales of shares of common stock, if any, under this prospectus will be made at market prices by any method that is deemed to be an "at-the-market" offering, as defined in Rule 415 under the Securities Act, including sales made directly on Nasdaq or any other trading market for our common stock. If authorized by us in writing, the Sales Agents may purchase shares of our common stock as principal.
Upon delivery of a placement notice to a Sales Agent, such Sales Agent will offer shares of our common stock subject to the terms and conditions of the Sales Agreement on a daily basis or as otherwise agreed upon by us and such Sales Agent. We will designate the maximum amount of common stock to be sold through the Sales Agents on a daily basis or otherwise determine such maximum amount together with the Sales Agents. Subject to the terms and conditions of the Sales Agreement, the Sales Agents will use their commercially reasonable efforts consistent with its normal trading and sales practices to sell on our behalf all of the shares of common stock requested to be sold by us. We may instruct the Sales Agents not to sell shares of common stock if the sales cannot be effected at or above the price designated by us in any such instruction. The Sales Agents or we may suspend the offering of shares of our common stock being made through the Sales Agents under the Sales Agreement upon proper notice to the other party. The Sales Agents and we each have the right, by giving written notice as specified in the Sales Agreement, to terminate the Sales Agreement in such party's sole discretion at any time. The offering of shares of our common stock pursuant to the Sales Agreement will otherwise terminate upon the termination of the Sales Agreement as provided therein.
The aggregate compensation payable to the Sales Agents as sales agents will be an amount up to 3.0% of the gross proceeds of any shares sold through it pursuant to the Sales Agreement. We have also agreed to reimburse the Sales Agents up to $75,000 of the Sales Agents' actual outside legal expenses incurred by the Sales Agents in connection with this offering. We have also agreed to reimburse the Sales Agents for certain ongoing fees of their legal counsel. We estimate that the total expenses of the offering payable by us, excluding commissions payable to the Sales Agents under the Sales Agreement, will be approximately $0.4 million.
The remaining sales proceeds, after deducting any expenses payable by us and any transaction fees imposed by any governmental, regulatory, or self-regulatory organization in connection with the sales, will equal our net proceeds for the sale of such shares of common stock.
The applicable Sales Agent will provide written confirmation to us following the close of trading on Nasdaq on each day in which shares of common stock are sold through it as sales agent under the Sales Agreement. Each confirmation will include the number of shares of common stock sold through it as sales agent on that day, the volume weighted average price of the shares of common stock sold, the percentage of the daily trading volume and the net proceeds to us.
Settlement for sales of shares of common stock will occur, unless the parties agree otherwise, on the first business day that is also a trading day following the date on which any sales were made in return for payment of the net proceeds to us. There is no arrangement for funds to be received in an escrow, trust or similar arrangement.
We will report at least quarterly the number of shares of common stock sold through the Sales Agents under the Sales Agreement, the net proceeds to us and the compensation paid by us to the Sales Agents in connection with the sales of shares of common stock during the relevant period.
In connection with the sales of shares of common stock on our behalf, the Sales Agents may be deemed to be "underwriters" within the meaning of the Securities Act, and the compensation paid to the Sales Agents may be deemed to be underwriting commissions or discounts. We have agreed in the Sales Agreement to provide indemnification and contribution to the Sales Agents against certain liabilities, including liabilities under the Securities Act. As sales agents, neither Leerink Partners LLC nor Cantor Fitzgerald & Co. will engage in any transactions that stabilize our common stock.

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LEGAL MATTERS
Latham & Watkins LLP, Chicago, Illinois, will pass upon certain legal matters for us in connection with the common stock offered by this prospectus supplement and the accompanying prospectus. Paul Hastings LLP, New York, New York, will pass upon certain legal matters for the Sales Agents.
EXPERTS
The consolidated financial statements of Harmony Biosciences Holdings, Inc. and Subsidiaries incorporated herein by reference have been audited by Deloitte & Touche LLP, an independent registered public accounting firm, as stated in their report. Such consolidated financial statements are incorporated by reference in reliance upon the report of such firm given their authority as experts in accounting and auditing.

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WHERE YOU CAN FIND MORE INFORMATION; INCORPORATION BY REFERENCE
Available Information
We file annual, quarterly and current reports, proxy statements and other information with the SEC. Our SEC filings are available to the public through the SEC's website at www.sec.gov. Our internet address is www.harmonybiosciences.com. Our Annual Reports on Form 10-K, Quarterly Reports on Form 10-Q, Current Reports on Form 8-K and other filings with the SEC are available, free of charge, through our website, as soon as reasonably practicable after those reports or filings are electronically filed with or furnished to the SEC. Information on our website or any other website is not incorporated by reference into this prospectus and you should not consider information contained on our website as part of this prospectus or the registration statement.
This prospectus supplement and the accompanying prospectus are part of a registration statement that we filed with the SEC and do not contain all of the information in the registration statement. The full registration statement may be obtained from the SEC or us, as provided below. Forms of the indenture and other documents establishing the terms of the offered securities are or may be filed as exhibits to the registration statement. Statements in this prospectus supplement or the accompanying prospectus about these documents are summaries and each statement is qualified in all respects by reference to the document to which it refers. You should refer to the actual documents for a more complete description of the relevant matters. You can obtain a copy of the registration statement from the SEC's website.
Incorporation of Certain Documents by Reference
The SEC's rules allow us to "incorporate by reference" information into this prospectus, which means that we can disclose important information to you by referring you to another document filed separately with the SEC. The information incorporated by reference is deemed to be part of this prospectus, and subsequent information that we file with the SEC will automatically update and supersede that information. Any statement contained in a previously filed document incorporated by reference will be deemed to be modified or superseded for purposes of this prospectus to the extent that a statement contained in this prospectus modifies or replaces that statement.
This prospectus supplement incorporates by reference the documents set forth below that have previously been filed with the SEC:

our Annual Report on Form 10-K for the fiscal year ended December 31, 2024, filed with the SEC on February 25, 2025; and

the description of our common stock contained in Exhibit 4.3 to our Annual Report on Form 10-K for the fiscal year ended December 31, 2020, filed with the SEC on March 25, 2021 and any amendment or report filed with the SEC for the purpose of updating the description.
We also incorporate by reference into this prospectus supplement additional documents that we may file with the SEC under Section 13(a), 13(c), 14 or 15(d) of the Exchange Act from the date of this prospectus supplement until we have sold all of the securities to which this prospectus supplement relates, or the applicable offering of shares of our common stock pursuant to this prospectus supplement is otherwise terminated. Information that is "furnished" to the SEC shall not be deemed incorporated by reference into this prospectus supplement, the accompanying prospectus or the registration statement of which this prospectus supplement is part.
You may request a free copy of any of the documents incorporated by reference in this prospectus supplement (other than exhibits, unless they are specifically incorporated by reference in the documents) by writing or telephoning us at the following address:
Harmony Biosciences Holdings, Inc.
630 W. Germantown Pike, Suite 215
Plymouth Meeting, PA 19462
(484) 539-9800

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Up to $200,000,000
Common Stock
PROSPECTUS SUPPLEMENT
Leerink Partners
Cantor
February 25, 2025
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PART II
INFORMATION NOT REQUIRED IN PROSPECTUS
Item 14. Other Expenses of Issuance and Distribution.
The following statement sets forth our expenses in connection with the offering described in this registration statement (all of which will be borne by us). All amounts shown are estimated.
SEC registration fee
$     *
Printing expenses
+
Legal fees and expenses
+
Accounting fees and expenses
+
Miscellaneous expenses
+
Trustee fees and expenses
+
Total
$ +
*
In accordance with Rules 456(b) and 457(r) of the Securities Act of 1933, as amended (the "Securities Act"), we are deferring payment of the registration fee for the securities offered by this prospectus, other than with respect to the registration fees applicable to the offering of up to $200,000,000 of shares of common stock pursuant to the sales agreement prospectus supplement.
+
Estimated expenses are not presently known and will be reflected in the applicable prospectus supplement.
Item 15. Indemnification of Directors and Officers.
Delaware General Corporation Law
Section 145(a) of the General Corporation Law of the State of Delaware (the "Delaware General Corporation Law") provides that a corporation may indemnify any person who was or is a party or is threatened to be made a party to any threatened, pending or completed action, suit or proceeding, whether civil, criminal, administrative or investigative (other than an action by or in the right of the corporation) by reason of the fact that the person is or was a director, officer, employee or agent of the corporation, or is or was serving at the request of the corporation as a director, officer, employee or agent of another corporation, partnership, joint venture, trust or other enterprise, against expenses (including attorneys' fees), judgments, fines and amounts paid in settlement actually and reasonably incurred by the person in connection with such action, suit or proceeding if the person acted in good faith and in a manner the person reasonably believed to be in or not opposed to the best interests of the corporation, and, with respect to any criminal action or proceeding, had no reasonable cause to believe the person's conduct was unlawful. The termination of any action, suit or proceeding by judgment, order, settlement, conviction or upon a plea of nolo contendere or its equivalent, shall not, of itself, create a presumption that the person did not act in good faith and in a manner which the person reasonably believed to be in or not opposed to the best interests of the corporation, and, with respect to any criminal action or proceeding, had reasonable cause to believe that the person's conduct was unlawful.
Section 145(b) of the Delaware General Corporation Law states that a corporation may indemnify any person who was or is a party or is threatened to be made a party to any threatened, pending or completed action or suit by or in the right of the corporation to procure a judgment in its favor by reason of the fact that the person is or was a director, officer, employee or agent of the corporation, or is or was serving at the request of the corporation as a director, officer, employee or agent of another corporation, partnership, joint venture, trust or other enterprise against expenses (including attorneys' fees) actually and reasonably incurred by the person in connection with the defense or settlement of such action or suit if the person acted in good faith and in a manner the person reasonably believed to be in or not opposed to the best interests of the corporation and except that no indemnification shall be made in respect of any claim, issue or matter as to which the person shall have been adjudged to be liable to the corporation unless and only to the

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extent that the Delaware Court of Chancery or the court in which such action or suit was brought shall determine upon application that, despite the adjudication of liability but in view of all the circumstances of the case, the person is fairly and reasonably entitled to indemnity for such expenses as the Delaware Court of Chancery or such other court shall deem proper.
Section 145(c) of the Delaware General Corporation Law provides that to the extent that a present or former director or officer of a corporation has been successful on the merits or otherwise in defense of any action, suit or proceeding referred to in subsections (a) and (b) of Section 145, or in defense of any claim, issue or matter therein, such person shall be indemnified against expenses (including attorneys' fees) actually and reasonably incurred by such person in connection therewith.
Section 145(d) of the Delaware General Corporation Law states that any indemnification under subsections (a) and (b) of Section 145 (unless ordered by a court) shall be made by the corporation only as authorized in the specific case upon a determination that indemnification of the present or former director, officer, employee or agent is proper in the circumstances because the person has met the applicable standard of conduct set forth in subsections (a) and (b) of Section 145. Such determination shall be made with respect to a person who is a director or officer at the time of such determination (1) by a majority vote of the directors who are not parties to such action, suit or proceeding, even though less than a quorum, (2) by a committee of such directors designated by majority vote of such directors, even though less than a quorum, (3) if there are no such directors, or if such directors so direct, by independent legal counsel in a written opinion or (4) by the stockholders.
Section 145(f) of the Delaware General Corporation Law states that the indemnification and advancement of expenses provided by, or granted pursuant to, the other subsections of Section 145 shall not be deemed exclusive of any other rights to which those seeking indemnification or advancement of expenses may be entitled under any bylaw, agreement, vote of stockholders or disinterested directors or otherwise, both as to action in such person's official capacity and as to action in another capacity while holding such office.
Section 145(g) of the Delaware General Corporation Law provides that a corporation shall have the power to purchase and maintain insurance on behalf of any person who is or was a director, officer, employee or agent of the corporation, or is or was serving at the request of the corporation as a director, officer, employee or agent of another corporation, partnership, joint venture, trust or other enterprise, against any liability asserted against such person and incurred by such person in any such capacity or arising out of such person's status as such, whether or not the corporation would have the power to indemnify such person against such liability under the provisions of Section 145.
Section 145(j) of the Delaware General Corporation Law states that the indemnification and advancement of expenses provided by, or granted pursuant to, Section 145 shall, unless otherwise provided when authorized or ratified, continue as to a person who has ceased to be a director, officer, employee or agent and shall inure to the benefit of the heirs, executors and administrators of such a person.
Certificate of Incorporation
The registrant's amended and restated certificate of incorporation provides that no director of the registrant shall have any personal liability to the registrant or its stockholders for monetary damages for any breach of fiduciary duty as a director, except to the extent such exemption from liability or limitation thereof is not permitted under the Delaware General Corporation Law as the same exists or hereafter may be amended. Any amendment, repeal or modification of this provision of the registrant's amended and restated certificate of incorporation, or the adoption of any provision inconsistent with the foregoing, shall not adversely affect any right or protection of a director of the registrant with respect to any act or omission occurring prior to such amendment, repeal, modification or adoption.
Bylaws
The registrant's amended and restated bylaws provide for the indemnification of the officers and directors of the registrant to the fullest extent permitted by the Delaware General Corporation Law. The amended and restated bylaws provide that each person who was or is made or is threatened to be made a party

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or is otherwise involved in any action, suit or proceeding, whether civil, criminal, administrative or investigative by reason of the fact that he or she, or a person for whom he or she is the legal representative, is or was a director or officer of the registrant or, while serving as a director or officer of the registrant, is or was serving at the request of the registrant as a director, officer, employee or agent of another corporation or of a partnership, joint venture, trust, enterprise or non-profit entity, including service with respect to employee benefit plans, against all liability and loss suffered and expenses (including attorneys' fees, judgments, fines ERISA excise taxes or penalties and amounts paid in settlement) reasonably incurred by such person in connection therewith, if such person acted in good faith and in a manner such person reasonably believed to be in or not opposed to the best interests of the registrant and, with respect to any criminal action or proceeding, had no reasonable cause to believe that such person's conduct was unlawful.
Insurance
The registrant maintains director and officer liability insurance, which covers directors and officers of the registrant against certain claims or liabilities arising out of the performance of their duties.
Indemnification Agreements
The registrant has entered into indemnification agreements with each of its directors and executive officers. These agreements provide for indemnification of the registrant's directors (and in certain cases their related venture capital funds) and executive officers to the fullest extent permitted by the Delaware General Corporation Law against all expenses, including attorneys' fees, judgments, fines and settlement amounts incurred by any such person in actions or proceedings, including actions by the registrant or in its right, arising out of such person's services as a director or officer of the registrant, any subsidiary of the registrant or any other company or enterprise to which the person provided services at the registrant's request. These agreements are intended to give the registrant's officers and directors additional contractual assurances regarding the scope of the indemnification set forth in its certificate of incorporation and bylaws and to provide additional procedural protections.
Item 16. Exhibits.
Exhibit
Number
Description
Incorporation by Reference
(where a report or registration statement is
indicated below, that document has been
previously filed with the SEC and the applicable
exhibit is incorporated by reference thereto)
1.1 Form of Underwriting Agreement. *
1.2 Sales Agreement, dated as of February 25, 2025, by and among Harmony Biosciences Holdings, Inc., Leerink Partners LLC and Cantor Fitzgerald & Co. Filed herewith.
3.1 Exhibit 3.1 to our Form 8-K filed August 21, 2020 (File No. 001-39450).
3.2 Exhibit 3.2 to our Form 8-K filed on August 21, 2020 (File No. 001-39450).
4.1 Exhibit 4.3 to our Form S-3 filed November 9, 2021 (File No. 333-260905).
4.2 Exhibit 4.1 to our Form S-1/A filed August 6, 2020 (File No. 333-240122).
4.3 Form of Certificate of Designation of Preferred Stock. *
4.4
Form of Specimen Preferred Stock Certificate.
*
4.5 Form of Warrant Agreement. *
4.6 Form of Depositary Agreement. *

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Exhibit
Number
Description
Incorporation by Reference
(where a report or registration statement is
indicated below, that document has been
previously filed with the SEC and the applicable
exhibit is incorporated by reference thereto)
4.7 Form of Rights Agreement. *
4.8 Form of Unit. *
5.1
Opinion of Latham & Watkins LLP.
Filed herewith.
23.1
Consent of Deloitte & Touche LLP.
Filed herewith.
23.2
Consent of Latham & Watkins LLP.
Included in Exhibit 5.1 filed herewith.
24
Powers of Attorney.
Included on the signature pages hereto.
25.1 Statement of Eligibility of Trustee. To be filed by amendment or via Form T-1 pursuant to Rule 305 of the Trust Indenture Act of 1939, as amended.
107
Calculation of Filing Fee Tables.
Filed herewith.
*
To be filed by amendment to the Registration Statement or incorporated by reference from documents filed or to be filed with the SEC under the Exchange Act.
Item 17. Undertakings.
(a)
The undersigned registrant hereby undertakes:
(1) To file, during any period in which offers or sales are being made, a post-effective amendment to this registration statement:
(i)
To include any prospectus required by Section 10(a)(3) of the Securities Act;
(ii)
To reflect in the prospectus any facts or events arising after the effective date of the registration statement (or the most recent post-effective amendment thereof) which, individually or in the aggregate, represent a fundamental change in the information set forth in the registration statement. Notwithstanding the foregoing, any increase or decrease in the volume of securities offered (if the total dollar value of securities offered would not exceed that which was registered) and any deviation from the low or high end of the estimated maximum offering range may be reflected in the form of prospectus filed with the SEC pursuant to Rule 424(b) if, in the aggregate, the changes in volume and price represent no more than a 20 percent change in the maximum aggregate offering price set forth in the "Calculation of Filing Fee Tables" in the effective registration statement; and
(iii)
To include any material information with respect to the plan of distribution not previously disclosed in the registration statement or any material change to such information in the registration statement.
provided, however, that paragraphs (a)(1)(i), (a)(1)(ii) and (a)(1)(iii) above do not apply if the information required to be included in a post-effective amendment by those paragraphs is contained in reports filed with or furnished to the SEC by the registrant pursuant to Section 13 or Section 15(d) of the Exchange Act that are incorporated by reference in the registration statement, or is contained in a form of prospectus filed pursuant to Rule 424(b) that is part of the registration statement.
(2) That, for the purpose of determining any liability under the Securities Act, each such post-effective amendment shall be deemed to be a new registration statement relating to the securities offered therein, and the offering of such securities at that time shall be deemed to be the initial bona fide offering thereof.
(3) To remove from registration by means of a post-effective amendment any of the securities being registered which remain unsold at the termination of the offering.

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(4) That, for the purpose of determining liability under the Securities Act to any purchaser:
(i)
Each prospectus filed by the registrant pursuant to Rule 424(b)(3) shall be deemed to be part of the registration statement as of the date the filed prospectus was deemed part of and included in the registration statement; and
(ii)
Each prospectus required to be filed pursuant to Rule 424(b)(2), (b)(5), or (b)(7) as part of a registration statement in reliance on Rule 430B relating to an offering made pursuant to Rule 415(a)(1)(i), (vii), or (x) for the purpose of providing the information required by Section 10(a) of the Securities Act shall be deemed to be part of and included in the registration statement as of the earlier of the date such form of prospectus is first used after effectiveness or the date of the first contract of sale of securities in the offering described in the prospectus. As provided in Rule 430B, for liability purposes of the issuer and any person that is at that date an underwriter, such date shall be deemed to be a new effective date of the registration statement relating to the securities in the registration statement to which that prospectus relates, and the offering of such securities at that time shall be deemed to be the initial bona fide offering thereof. Provided, however, that no statement made in a registration statement or prospectus that is part of the registration statement or made in a document incorporated or deemed incorporated by reference into the registration statement or prospectus that is part of the registration statement will, as to a purchaser with a time of contract of sale prior to such effective date, supersede or modify any statement that was made in the registration statement or prospectus that was part of the registration statement or made in any such document immediately prior to such effective date.
(5) That, for the purpose of determining liability of the registrant under the Securities Act to any purchaser in the initial distribution of the securities, the undersigned registrant undertakes that in a primary offering of securities of the undersigned registrant pursuant to this registration statement, regardless of the underwriting method used to sell the securities to the purchaser, if the securities are offered or sold to such purchaser by means of any of the following communications, the undersigned registrant will be a seller to the purchaser and will be considered to offer or sell such securities to such purchaser:
(i)
Any preliminary prospectus or prospectus of the undersigned registrant relating to the offering required to be filed pursuant to Rule 424;
(ii)
Any free writing prospectus relating to the offering prepared by or on behalf of the undersigned registrant or used or referred to by the undersigned registrant;
(iii)
The portion of any other free writing prospectus relating to the offering containing material information about the undersigned registrant or its securities provided by or on behalf of the undersigned registrant; and
(iv)
Any other communication that is an offer in the offering made by the undersigned registrant to the purchaser.
(6) The undersigned registrant hereby undertakes that, for purposes of determining any liability under the Securities Act, each filing of the registrant's annual report pursuant to Section 13(a) or 15(d) of the Exchange Act (and, where applicable, each filing of an employee benefit plan's annual report pursuant to Section 15(d) of the Exchange Act) that is incorporated by reference in the registration statement shall be deemed to be a new registration statement relating to the securities offered therein, and the offering of such securities at that time shall be deemed to be the initial bona fide offering thereof.
(7) Insofar as indemnification for liabilities arising under the Securities Act may be permitted to directors, officers and controlling persons of the registrant pursuant to the foregoing provisions, or otherwise, the registrant has been advised that in the opinion of the SEC such indemnification is against public policy as expressed in the Securities Act and is, therefore, unenforceable. In the event that a claim for indemnification against such liabilities (other than the payment by the registrant of expenses incurred or paid by a director, officer or controlling person of the registrant in the successful defense of any action, suit or proceeding) is asserted by such director, officer or controlling person in connection with the securities being registered, the registrant will, unless in the opinion of its counsel the matter has been settled by

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controlling precedent, submit to a court of appropriate jurisdiction the question whether such indemnification by it is against public policy as expressed in the Act and will be governed by the final adjudication of such issue.
(8) The undersigned registrant hereby undertakes to file an application for the purpose of determining the eligibility of the trustee to act under subsection (a) of Section 310 of the Trust Indenture Act (the "Act") in accordance with the rules and regulations prescribed by the SEC under Section 305(b)(2) of the Act.

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SIGNATURES
Pursuant to the requirements of the Securities Act, the registrant certifies that it has reasonable grounds to believe that it meets all of the requirements for filing on Form S-3 and has duly caused this registration statement to be signed on its behalf by the undersigned, thereunto duly authorized, in the City of Plymouth Meeting, State of Pennsylvania, on February 25, 2025.
HARMONY BIOSCIENCES HOLDINGS, INC.
By:
/s/ Jeffrey M. Dayno
Jeffrey M. Dayno
President, Chief Executive Officer and Director

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POWER OF ATTORNEY
Each person whose signature appears below constitutes and appoints Jeffrey M. Dayno and Sandip Kapadia, and each of them, as his or her true and lawful attorney-in-fact and agent, with full power of substitution and resubstitution, for such person and in his or her name, place and stead, in any and all capacities, to sign any or all further amendments (including post-effective amendments) to this registration statement (and any additional registration statement related hereto permitted by Rule 462(b) promulgated under the Securities Act (and all further amendments, including post-effective amendments, thereto)), and to file the same, with all exhibits thereto, and other documents in connection therewith, with the SEC, granting unto said attorneys-in-fact and agents, and each of them, full power and authority to do and perform each and every act and thing requisite and necessary to be done in and about the premises, as fully to all intents and purposes as he might or could do in person, hereby ratifying and confirming all that said attorney-in-fact and agent, or his substitute or substitutes, may lawfully do or cause to be done by virtue hereof.
Pursuant to the requirements of the Securities Act, this registration statement has been signed by the following persons in the capacities and on the dates indicated below.
Signature
Title
Date
/s/ Jeffrey M. Dayno
Jeffrey M. Dayno
President, Chief Executive Officer and Director (Principal Executive Officer)
February 25, 2025
/s/ Sandip Kapadia
Sandip Kapadia
Chief Financial Officer and Chief Administrative Officer (Principal Financial Officer)
February 25, 2025
/s/ Jeffrey S. Aronin
Jeffrey S. Aronin
Chairman of the Board
February 25, 2025
/s/ Peter Anastasiou
Peter Anastasiou
Director
February 25, 2025
/s/ Antonio Gracias
Antonio Gracias
Director
February 25, 2025
/s/ R. Mark Graf
R. Mark Graf
Director
February 25, 2025
/s/ Juan A. Sabater
Juan A. Sabater
Director
February 25, 2025
/s/ Gary Sender
Gary Sender
Director
February 25, 2025
/s/ Linda Szyper
Linda Szyper
Director
February 25, 2025
/s/ Andreas Wicki
Andreas Wicki
Director
February 25, 2025

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