02/24/2026 | Press release | Distributed by Public on 02/24/2026 06:11
Management's Discussion and Analysis of Financial Condition and Results of Operations.
The following discussion and analysis of our financial condition and results of operations should be read together with our consolidated financial statements and related notes appearing at the end of this Annual Report on Form 10-K. Some of the information contained in this discussion and analysis or set forth elsewhere in this Annual Report on Form 10-K, including information with respect to our plans and strategy for our business, includes forward-looking statements that involve risks and uncertainties. As a result of many factors, including those factors set forth in the "Risk Factors" section of this Annual Report on Form 10-K, our actual results could differ materially from the results described in or implied by the forward-looking statements contained in the following discussion and analysis.
Overview
We are a clinical-stage biopharmaceutical company focused on developing small molecules to improve the lives of patients with genetically defined rare diseases in areas of high unmet medical need. Our lead product candidate, pociredir, is in clinical development for the potential treatment of SCD.
In February 2026, we announced updated 20 mg cohort results from the PIONEER trial as of the December 23, 2025 data cut off date showing:
We are currently activating sites in an open-label extension trial to evaluate longer-term safety and PD durability in patients who completed the PIONEER trial. We plan to provide details regarding the design of the next trial in the second quarter of 2026 following receipt of meeting minutes from our End-of-Phase meeting with the FDA. Pending feedback from the FDA, we plan to initiate a potential registration-enabling trial in the second half of 2026. We also plan to engage with the EMA in mid-2026 to obtain protocol assistance and feedback on the design of the next trial.
In addition to our product candidates, we developed a discovery approach that we employ to systematically identify and validate cellular drug targets that can potentially modulate gene expression to treat known root causes of genetically defined rare diseases. Our discovery approach led to the identification of pociredir for SCD, as well as other drug candidates. We are applying our discovery capabilities to explore additional mechanisms that may complement pociredir's mechanism of action to induce HbF for the potential treatment of SCD. We also presented preclinical data for FTX-6274, an oral EED inhibitor candidate, at the European Society for Medical Oncology (ESMO) Congress 2025, demonstrating tumor growth inhibition in castration resistant prostate cancer models.
Based on results from IND-enabling studies, we have decided not to advance our program for bone marrow failure syndromes into clinical development and will focus our resources on advancing pociredir and our core benign hematology programs.
We have incurred significant operating losses since our inception and we expect to continue to incur significant operating losses for the foreseeable future. Our ability to generate product revenue sufficient to achieve profitability, if ever, will depend heavily on the successful development and eventual commercialization of one or more of our product candidates. Our net losses were $74.9 million and $9.7 million for the years ended December 31, 2025 and 2024, respectively. As of December 31, 2025, we had an accumulated deficit of $594.3 million. We expect our expenses and operating losses will increase over the next several years in connection with our ongoing activities, as we:
As a result, we will need substantial additional funding to support our continuing operations and pursue our growth strategy. Until such time as we can generate significant revenue from product sales, if ever, we expect to finance our operations through a combination of equity offerings, debt financings, collaborations, strategic alliances and marketing, distribution or licensing arrangements. We may be unable to raise additional funds or enter into such other agreements or arrangements when needed on favorable terms, or at all. If we fail to raise capital or enter into such agreements as, and when, needed, we may have to significantly delay, scale back or discontinue the development and commercialization of one or more of our product candidates, or grant rights to develop and market our product candidates even if we would otherwise prefer to develop and market such product candidates ourselves.
Because of the numerous risks and uncertainties associated with drug development, we are unable to predict the timing or amount of increased expenses or the timing of when or if we will be able to achieve or maintain profitability. Even if we are able to generate product sales, we may not become profitable. If we fail to become profitable or are unable to sustain profitability on a continuing basis, then we may be unable to continue our operations at planned levels and be forced to reduce or terminate our operations.
As of December 31, 2025, we had $352.3 million in cash, cash equivalents, and marketable securities. We believe that our existing cash, cash equivalents, and marketable securities as of December 31, 2025 will enable us to fund our operating expenses and capital expenditure requirements into 2029. We have based this estimate on assumptions that may prove to be wrong, and we could exhaust our available capital resources sooner than we expect. See "-Liquidity and Capital Resources."
Components of Results of Operations
Revenue
We have not generated any revenue from product sales and do not expect to generate revenue from the sale of products for several years, if at all. If our development efforts for our current or future product candidates are successful and result in marketing approval, we may generate revenue in the future from product sales. We cannot predict if, when or to what extent we will generate revenue from the commercialization and sale of our product candidates. We may never succeed in obtaining regulatory approval for any of our product candidates.
In May 2024, we entered into a collaboration and license agreement with Sanofi, pursuant to which we granted Sanofi an exclusive license under certain intellectual property rights to commercialize losmapimod, an oral small molecule that we were developing for the treatment of FSHD outside of the United States and received an upfront payment of $80.0 million.
During the year ended December 31, 2025, we recorded a $1.0 million reduction in research and development expenses in connection with global development activities for losmapimod. During the year ended December 31, 2025, we recognized no revenue associated with the Sanofi territory-specific manufacturing activities for losmapimod. As a result of the suspension of future development of losmapimod following our September 2024 announcement that there was no statistically significant difference between losmapimod and placebo on the primary endpoint in the Phase 3 REACH trial, Sanofi terminated the license. Accordingly, we will not recognize additional revenues under the Sanofi collaboration agreement.
In the future, we may enter into additional license or collaboration agreements for our product candidates or intellectual property, and we may generate revenue in the future from payments as a result of such license or collaboration agreements.
Operating Expenses
Research and Development Expenses
Research and development expenses represent costs incurred by us for the discovery, development, and manufacture of our product candidates and include:
We expense research and development costs as incurred. We recognize expenses for certain development activities, such as clinical trials and manufacturing, based on an evaluation of the progress to completion of specific tasks using data such as patient enrollment or other information provided to us by our vendors. Payments for these activities are based on the terms of the individual agreements, which may differ from the pattern of expenses incurred. Non-refundable advance payments for goods or services to be received in the future for use in research and development activities are recorded as prepaid expenses. These amounts are recognized as an expense as the goods are delivered or the related services are performed, or until it is no longer expected that the goods will be delivered or the services rendered.
External costs represent a significant portion of our research and development expenses, which we track on a program-by-program basis following the nomination of a development candidate. Our internal research and development expenses consist primarily of personnel-related expenses, including stock-based compensation expense. We do not track our internal research and development expenses on a program-by-program basis as the resources are deployed across multiple projects.
The following table summarizes our external research and development expenses by program for the years ended December 31, 2025 and 2024. Pre-development candidate expenses, unallocated expenses and internal research and development expenses are classified separately. Payments to or reimbursements from Sanofi related to global development activities are accounted for as an increase to or reduction of losmapimod external expenses.
|
Year Ended |
||||||||
|
(in thousands) |
2025 |
2024 |
||||||
|
Pociredir external expenses |
$ |
19,994 |
$ |
8,577 |
||||
|
Losmapimod external expenses |
941 |
20,801 |
||||||
|
Pre-development candidate expenses and unallocated expenses |
19,061 |
14,008 |
||||||
|
Internal research and development expenses |
16,107 |
20,000 |
||||||
|
Total research and development expenses |
$ |
56,103 |
$ |
63,386 |
||||
The successful development of our product candidates is highly uncertain. At this time, we cannot reasonably estimate or know the nature, timing, and estimated costs of the efforts that will be necessary to complete the remainder of the development of our product candidates. We are also unable to predict when, if ever, material net cash inflows will commence from our product candidates, if approved. This is due to the numerous risks and uncertainties associated with developing our product candidates, including the uncertainty related to:
A change in the outcome of any of these variables with respect to the development of any of our product candidates would significantly change the costs and timing associated with the development of that product candidate, and potentially other candidates.
Research and development activities account for a significant portion of our operating expenses. We expect our research and development expenses to increase in future periods as we continue to implement our business strategy, which includes advancing pociredir for the treatment of SCD, expanding our research and development efforts, including hiring additional personnel to support our research and development efforts, and seeking regulatory approvals for our product candidates that successfully complete clinical trials. In addition, product candidates in later stages of clinical development generally incur higher development costs than those in earlier stages of clinical development, primarily due to the increased size and duration of later-stage clinical trials. As a result, we expect our research and development expenses to increase as our product candidates advance into later stages of clinical development. However, we do not believe that it is possible at this time to accurately project total program-specific expenses through approval and commercialization. There are numerous factors associated with obtaining regulatory approval and the successful commercialization of any of our product candidates, including future trial design and various regulatory requirements, many of which cannot be determined with accuracy at this time based on our stage of development.
General and Administrative Expenses
General and administrative expenses consist of personnel-related costs, including salaries, benefits and stock-based compensation expense, for our personnel in executive, finance and accounting, human resources, business operations and other administrative functions, legal fees related to patent, intellectual property and corporate matters, fees paid for accounting and tax services, consulting fees and facility-related costs not otherwise included in research and development expenses.
We expect that our general and administrative expenses will increase in the future to support continued research and development activities and planned commercialization activities, including establishing a sales, marketing and distribution infrastructure to commercialize any medicines for which we may obtain marketing approval. These increases will likely include increased costs related to the hiring of additional personnel, legal, audit, filing fees, and general compliance and consulting expenses, among other expenses.
Other Income, Net
Other income, net consists primarily of interest income related to our investments in cash equivalents and marketable securities.
Results of Operations
Comparison of the Years Ended December 31, 2025 and 2024
The following summarizes our results of operations for the years ended December 31, 2025 and 2024, along with the changes in those items in dollars:
|
Year Ended |
Change |
|||||||||||
|
(in thousands) |
2025 |
2024 |
$ |
|||||||||
|
Collaboration revenue |
- |
80,000 |
(80,000 |
) |
||||||||
|
Operating expenses: |
||||||||||||
|
Research and development |
56,103 |
63,386 |
(7,283 |
) |
||||||||
|
General and administrative |
28,666 |
36,448 |
(7,782 |
) |
||||||||
|
Restructuring expenses |
- |
2,063 |
(2,063 |
) |
||||||||
|
Total operating expenses |
84,769 |
101,897 |
(17,128 |
) |
||||||||
|
Loss from operations |
(84,769 |
) |
(21,897 |
) |
(62,872 |
) |
||||||
|
Other income, net |
9,889 |
12,172 |
(2,283 |
) |
||||||||
|
Net loss |
$ |
(74,880 |
) |
$ |
(9,725 |
) |
$ |
(65,155 |
) |
|||
Collaboration Revenue
Collaboration revenue decreased by $80.0 million from the year ended December 31, 2024 to the year ended December 31, 2025. The decrease was attributable to the recognition of $80.0 million of revenue associated with the upfront license payment received during the year ended December 31, 2024 under the now terminated Sanofi collaboration agreement.
Research and Development Expenses
The following table summarizes our research and development expenses for the years ended December 31, 2025 and 2024:
|
Year Ended |
Change |
|||||||||||
|
(in thousands) |
2025 |
2024 |
$ |
|||||||||
|
External research and development |
$ |
31,744 |
$ |
36,327 |
$ |
(4,583 |
) |
|||||
|
Employee compensation |
16,108 |
20,000 |
(3,892 |
) |
||||||||
|
Laboratory supplies |
2,361 |
1,528 |
833 |
|||||||||
|
Facility costs |
4,449 |
4,483 |
(34 |
) |
||||||||
|
Other |
1,441 |
1,048 |
393 |
|||||||||
|
Total research and development expenses |
$ |
56,103 |
$ |
63,386 |
$ |
(7,283 |
) |
|||||
Research and development expense decreased by $7.3 million from $63.4 million for the year ended December 31, 2024 to $56.1 million for the year ended December 31, 2025. The decrease in research and development expense was primarily attributable to the following:
General and Administrative Expenses
The following table summarizes our general and administrative expenses for the years ended December 31, 2025 and 2024:
|
Year Ended |
Change |
|||||||||||
|
(in thousands) |
2025 |
2024 |
$ |
|||||||||
|
Employee compensation |
$ |
17,328 |
$ |
19,754 |
$ |
(2,426 |
) |
|||||
|
Professional services |
7,621 |
11,999 |
(4,378 |
) |
||||||||
|
Facility costs |
1,194 |
1,483 |
(289 |
) |
||||||||
|
Other |
2,523 |
3,212 |
(689 |
) |
||||||||
|
Total general and administrative expenses |
$ |
28,666 |
$ |
36,448 |
$ |
(7,782 |
) |
|||||
General and administrative expenses decreased by $7.7 million from $36.4 million for the year ended December 31, 2024 to $28.7 million for the year ended December 31, 2025. The decrease in general and administrative expenses was primarily attributable to the following:
Other Income, Net
Other income, net decreased by $2.3 million from $12.2 million for the year ended December 31, 2024 to $9.9 million for the year ended December 31, 2025. The decrease was primarily due to a decrease in our average cash, cash equivalents, and marketable securities balance, and a decreased rate of return due to declining interest rates.
Liquidity and Capital Resources
Sources of Liquidity
We have incurred significant operating losses since our inception and expect to continue to incur significant operating losses for the foreseeable future and may never become profitable. We have not yet commercialized any of our product candidates, which are in various phases of preclinical and clinical development, and we do not expect to generate revenue from sales of any products for several years, if at all. As of December 31, 2025, we have funded our operations primarily with aggregate gross proceeds of $967.5 million from the sale of shares of our capital stock and pre-funded warrants and from upfront payments received under our collaboration and license agreements. As of December 31, 2025, we had cash, cash equivalents, and marketable securities of $352.3 million.
In February 2024, we entered into a controlled equity offeringsm agreement with Cantor Fitzgerald & Co. and Stifel, Nicolaus & Company, Incorporated, as agents, with respect to an at-the-market offering program pursuant to which we may offer and sell, from time to time in our sole discretion, shares of our common stock, par value $0.001 per share, having an aggregate offering price of up to $100.0 million through the agents. As of December 31, 2025, we have not issued or sold any shares of common stock under the at-the-market offering program.
In December 2025, pursuant to an underwriting agreement with J.P. Morgan Securities LLC, Leerink Partners LLC, and Cantor Fitzgerald & Co., we and issued and sold (i) 11,851,853 shares of our common stock at a public offering price of $13.50 per share and (ii) pre-funded warrants to purchase up to 1,111,193 shares of our common stock at a public offering price of $13.499 per pre-funded warrant. The net proceeds of the offering were $164.2 million, after deducting underwriting discounts and commissions and offering expenses.
Cash Flows
The following table provides information regarding our cash flows for the years ended December 31, 2025 and 2024:
|
Year Ended |
||||||||
|
(in thousands) |
2025 |
2024 |
||||||
|
Net cash used in operating activities |
$ |
(60,065 |
) |
$ |
(2,218 |
) |
||
|
Net cash provided by investing activities |
30,719 |
32,230 |
||||||
|
Net cash provided by financing activities |
168,667 |
2,746 |
||||||
|
Net increase in cash, cash equivalents, and restricted cash |
$ |
139,321 |
$ |
32,758 |
||||
Net Cash Used in Operating Activities
Net cash used in operating activities was $60.1 million during the year ended December 31, 2025 compared to $2.2 million during the year ended December 31, 2024. The increase in net cash used in operating activities of $57.9 million was primarily due to an increase in net loss.
Net Cash Provided by Investing Activities
Net cash provided by investing activities was $30.7 million during the year ended December 31, 2025 compared to $32.2 million during the year ended December 31, 2024. The decrease in net cash provided by investing activities of $1.5 million was primarily due to a decrease in net maturities of marketable securities during the year ended December 31, 2025, as compared to the year ended December 31, 2024.
Net Cash Provided by Financing Activities
Net cash provided by financing activities was $168.7 million during the year ended December 31, 2025 compared to $2.7 million during the year ended December 31, 2024. Net cash provided by financing activities during the year ended December 31, 2025 primarily consisted of net proceeds of $164.2 million from the December 2025 public offering of our common stock and pre-funded warrants. Net cash provided by financing activities during the year ended December 31, 2024 consisted of net proceeds of $2.7 million from the issuance of common stock under our benefit plans.
Funding Requirements
We expect our expenses to increase substantially in connection with our ongoing research and development activities, particularly as we continue the research and development of, initiate clinical trials of, and seek marketing approval for, our product candidates, some of which are in the discovery stage of development. In addition, we expect to incur additional costs to support the growth of our organization when appropriate. As a result, we expect to incur substantial operating losses and negative operating cash flows for the foreseeable future.
Based on our current operating plan, we believe that our existing cash, cash equivalents, and marketable securities as of December 31, 2025 will enable us to fund our operating expenses and capital expenditure requirements into 2029. However, we have based this estimate on assumptions that may prove to be wrong and we could exhaust our capital resources sooner than we expect.
Our funding requirements and timing and amount of our operating expenditures will depend largely on:
A change in the outcome of any of these or other variables with respect to the development of any of our product candidates could significantly change the costs and timing associated with the development of that product candidate. We will need to continue to rely on additional financing to achieve our business objectives.
In addition to the variables described above, if and when any of our product candidates successfully complete development, we will incur substantial additional costs associated with regulatory filings, marketing approval, post-marketing requirements, maintaining our intellectual property rights, and regulatory protection, in addition to other commercial costs. We cannot reasonably estimate these costs at this time.
Until such time, if ever, as we can generate substantial product revenue, we expect to finance our cash needs through a combination of equity offerings, debt financings, collaboration arrangements, strategic alliances and marketing, distribution or licensing arrangements. We currently have no credit facility or committed sources of capital. To the extent that we raise additional capital through the future sale of equity securities, the ownership interests of our stockholders will be diluted, and the terms of these securities may include liquidation or other preferences that adversely affect the rights of our existing common stockholders. If we raise additional funds through the issuance of debt securities, these securities could contain covenants that would restrict our operations. We may require additional capital beyond our currently anticipated amounts, and additional capital may not be available on reasonable terms, or at all. If we raise additional funds through collaboration arrangements, strategic alliances or marketing, distribution or licensing arrangements in the future, we may have to relinquish valuable rights to our technologies, future revenue streams or product candidates, or grant licenses on terms that may not be favorable to us. If we are unable to raise additional funds through equity or debt financings when needed, we may be required to delay, limit, reduce or terminate development or future commercialization efforts or grant rights to develop and market product candidates that we would otherwise prefer to develop and market ourselves.
Critical Accounting Policies and Estimates
Our management's discussion and analysis of our financial condition and results of operations are based on our consolidated financial statements, which have been prepared in accordance with generally accepted accounting principles in the United States. The preparation of these consolidated financial statements requires us to make judgments and estimates that affect the reported amounts of assets and liabilities, the disclosure of contingent assets and liabilities at the date of the consolidated financial statements, and the reported amounts of expenses during the reporting periods. Our estimates are based on our historical experience, known trends and events, and on various other factors that we believe are reasonable under the circumstances, the results of which form the basis for making judgments about the carrying value of assets and liabilities and amount of expense recognized that are not readily apparent from other sources. Actual results may differ from these estimates under different assumptions or conditions. We evaluate our estimates and assumptions on an ongoing basis. The effects of material revisions in estimates, if any, will be reflected in the consolidated financial statements prospectively from the date of change in estimates.
We believe that the accounting policies discussed below are critical to understanding our historical and future performance, as these policies relate to the most significant areas involving management's judgments and estimates. See Note 2 to our consolidated financial statements included elsewhere in this Annual Report on Form 10-K for a description of our other significant accounting policies.
Collaborative Arrangements
At contract inception, we analyze our collaboration arrangements to assess whether such arrangements involve joint operating activities performed by parties that are both active participants in the activities and are exposed to significant risks and rewards dependent on the commercial success of such activities, and therefore within the scope of the Financial Accounting Standards Board Accounting Standards Codification, or ASC, Topic 808, Collaborative Arrangements, or ASC 808. This assessment is performed on an ongoing basis throughout the collaboration based on changes in the responsibilities of the parties in the arrangement. For collaboration arrangements within the scope of ASC 808 that contain multiple elements, we first determine which elements of the collaboration are deemed to be within the scope of ASC 808 and which elements of the collaboration are more reflective of a vendor-customer relationship and are therefore within the scope of ASC 606, Revenue from Contracts with Customers, or ASC 606.
For elements of collaboration arrangements that are accounted for pursuant to ASC 808, an appropriate recognition method is determined and applied consistently, either by analogy to authoritative accounting literature or by applying a reasonable and rational policy election. We evaluate the income statement classification for presentation of amounts due from or owed to collaborators associated with multiple activities in a collaboration arrangement based on the nature of each separate activity. We have made an accounting policy election to account for research and development reimbursements received from our collaboration partner that are outside of the scope of ASC 606 as a reduction of research and development expenses to best reflect the economics and nature of the transaction in the context of the unit-of-account.
Revenue Recognition
We account for revenue recognition under ASC 606. We recognize revenue pursuant to ASC 606 when our customer obtains control of promised goods or services in an amount that reflects the consideration which we expect to receive in exchange for those goods or services.
At contract inception, once the contract is determined to be within the scope of ASC 606, we assess the goods or services promised within the contract and determine those that are performance obligations. We then determine the transaction price and allocate it to the identified performance obligations. As part of the accounting for these arrangements, we must use significant judgment to determine the number of performance obligations and the transaction price, including the determination of whether milestones or other variable consideration should be included in the transaction price.
We use judgment to determine whether milestones or other variable consideration should be included in the transaction price. As part of management's evaluation of the transaction price, we consider numerous factors, including whether the achievement of the milestones is outside of our control, contingent upon the efforts of others or subject to the risks of success. If we conclude it is probable that a significant revenue reversal would not occur, the associated milestone payment is included in the transaction price. Milestone payments that are based on the occurrence of events not within our control, such as regulatory approvals, are generally not considered probable of being achieved until the underlying events occur or the associated approvals are received. At the end of each reporting period, we re-evaluate the estimated variable consideration included in the transaction price and any related constraint, and if necessary, adjust the estimate of the overall transaction price. Any such adjustments are recorded on a cumulative catch-up basis in the period of adjustment. Changes to the constraint of variable consideration can have a material effect on the amount of revenue recognized in the period.
If the contract contains a single performance obligation, the entire transaction price is allocated to the single performance obligation. Contracts that contain multiple performance obligations require an allocation of the transaction price to each performance obligation on a relative standalone selling price basis, except for any variable consideration that meets the criteria to be allocated entirely to a single performance obligation or to a distinct service that forms part of a single performance obligation.
We recognize as revenue the amount of the transaction price that is allocated to the respective performance obligation when (or as) the performance obligation is satisfied, either at a point in time or over time. If the performance obligation is satisfied over time, we recognize revenue based on the use of either an output or input method. The estimation of measure of progress is complex, involves significant judgment, and is affected by our estimates of the total costs required to complete the performance obligations, including the total internal personnel costs and external costs to be incurred. Changes in these estimates can have a material effect on our revenue recognition. If the entity does not satisfy a performance obligation over time, the related performance obligation is satisfied at a point in time by transferring the control of a promised good or service to a customer.
Accrued Research and Development Expenses
As part of the process of preparing our consolidated financial statements, we are required to estimate our accrued expenses as of each balance sheet date. This process involves reviewing open contracts and purchase orders, communicating with our personnel to identify services that have been performed on our behalf and estimating the level of service performed and the associated cost incurred for the service when we have not yet been invoiced or otherwise notified of the actual cost. The majority of our service providers invoice us monthly in arrears for services performed or when contractual milestones are met. We make estimates of our accrued expenses as of each balance sheet date based on facts and circumstances known to us at that time. We periodically confirm the accuracy of our estimates with the service providers and make adjustments if necessary. The significant estimates in our accrued research and development expenses include the costs incurred for services performed by our vendors in connection with research and development activities for which we have not yet been invoiced.
We base our expenses related to research and development activities on our estimates of the services received and efforts expended pursuant to quotes and contracts with vendors that conduct research and development on our behalf. The financial terms of these agreements are subject to negotiation, vary from contract to contract and may result in uneven payment flows. There may be instances in which payments made to our vendors will exceed the level of services provided and result in a prepayment of the research and development expense. In accruing service fees, we estimate the time period over which services will be performed and the level of effort to be expended in each period. If the actual timing of the performance of services or the level of effort varies from our estimate, we adjust the accrual or prepaid expense accordingly. Non-refundable advance payments for goods and services that will be used in future research and development activities are expensed when the activity has been performed or when the goods have been received rather than when the payment is made.
Although we do not expect our estimates to be materially different from amounts actually incurred, if our estimates of the status and timing of services performed differ from the actual status and timing of services performed, it could result in us reporting amounts that are too high or too low in any particular period. To date, there have been no material differences between our estimates of such expenses and the amounts actually incurred.
Stock-Based Compensation
We measure stock-based compensation expense related to all restricted stock awards, restricted stock units, and stock options based on the fair value of the award on the date of grant. We recognize compensation expense for these awards over the requisite service period, which is generally the vesting period of the respective award. Generally, we issue awards with only service-based vesting conditions and record the expense for these awards using the straight-line method. We have also granted certain stock-based awards with performance-based vesting conditions. We recognize compensation expense for awards with performance-based vesting conditions over the remaining service period using an accelerated attribution method when management determines that achievement of the performance condition is probable. At each reporting date, we evaluate if the achievement of a performance-based milestone is probable based on the expected satisfaction of the performance conditions.
We determine the fair value of restricted stock awards and restricted stock units based on the estimated fair value of our common stock on the date of grant, less any applicable purchase price. We estimate the fair value of stock options granted using the Black-Scholes option-pricing model. The determination of the grant date fair value of stock options using an option pricing model is affected principally by our estimated fair value of our common stock and requires management to make a number of other assumptions, including the expected term of the option, the estimated volatility of the underlying shares, the risk-free interest rate, and expected dividends. The assumptions used in the determination of the grant date fair value of stock options represent management's best estimates at the time of measurement. Given the lack of public market for our common stock prior to the closing of our IPO and a lack of company-specific historical and implied volatility data, we based the
estimate of expected volatility on the historical volatility of a representative group of publicly traded companies for which historical information is available. The historical volatility is calculated based on a period of time commensurate with the assumption used for the expected term. We use the simplified method to calculate the expected term for all stock options. We utilize this method as we do not have sufficient historical exercise data to provide a reasonable basis upon which to estimate the expected term. The risk-free interest rate is based on a U.S. treasury instrument whose term is consistent with the expected term of the stock options. The expected dividend yield is assumed to be zero as we have never paid dividends and do not have current plans to pay any dividends on common stock.
In future periods, we expect stock-based compensation expense to increase, due in part to our existing unrecognized stock-based compensation expense and as we grant additional stock-based awards to continue to attract and retain our employees.
Income Taxes
We account for income taxes using the asset and liability method, which requires the recognition of deferred tax assets and liabilities for the expected future tax consequences of events that have been recognized in the consolidated financial statements or in our tax returns. Under this method, deferred tax assets and liabilities are determined based on differences between the financial statement carrying amounts and the tax bases of the assets and liabilities using the enacted tax rates in effect in the years in which the differences are expected to reverse. A valuation allowance against deferred tax assets is recorded if, based on the weight of the available evidence, it is more likely than not that some or all of the deferred tax assets will not be realized. Potential for recovery of deferred tax assets is evaluated by considering several factors, including estimating the future taxable profits expected, estimating future reversals of existing taxable temporary differences, considering taxable profits in carryback periods, and considering prudent and feasible tax planning strategies.
We account for uncertain tax positions using a more-likely-than-not threshold for recognizing and resolving uncertain tax positions. The evaluation of uncertain tax positions is based on factors including, but not limited to, changes in the law, the measurement of tax positions taken or expected to be taken in tax returns, the effective settlement of matters subject to audit, new audit activity, and changes in facts or circumstances related to a tax position. As of each balance sheet date, we did not have any uncertain tax positions.
Recently Issued Accounting Pronouncements
A description of recently issued accounting pronouncements that may potentially impact our financial position and results of operations is disclosed in Note 2 to our audited consolidated financial statements appearing elsewhere in this Annual Report on Form 10-K.