Item 1.01 Entry into a Material Definitive Agreement.

On July 2, 2026, Enanta Pharmaceuticals, Inc. (the "Corporation") entered into an Open Market Sale Agreement^SM (the "Sales Agreement") with Jefferies LLC, as sales agent (the "Agent"), pursuant to which the Corporation may offer and sell shares (the "Shares") of its common stock, $0.01 par value per share ("Common Stock"), from time to time through the Agent.

The Common Stock is being offered and sold pursuant to the Corporation's previously filed and currently effective shelf registration statement on Form S-3, which was filed with the Securities and Exchange Commission (the "Commission") on February 11, 2026 and declared effective on February 20, 2026, containing a base prospectus (Registration Statement No. 333-293390). The Corporation filed a prospectus supplement dated July 2, 2026 with the Commission in connection with the offer and sale of the Shares. Pursuant to the prospectus supplement, the Corporation may offer and sell Shares having an aggregate offering price of up to $75,000,000.

Sales of the Shares through the Agent, if any, will be made by any method permitted by law deemed to be an "at the market offering" as defined in Rule 415(a)(4) under the Securities Act of 1933, as amended, including, without limitation, sales made directly on The Nasdaq Global Select Market or any other existing trading market for the Common Stock. The Agent will use commercially reasonable efforts to sell Common Stock from time to time, based upon instructions from the Corporation (including any price, time or size limits or other parameters or conditions the Corporation may impose). The Corporation has no obligation to sell any of the Shares under the Sales Agreement.

The Corporation will pay the Agent a commission of up to 3.0% of the gross sales price per share of Common Stock sold through the Agent under the Sales Agreement. The Corporation has also provided the Agent with customary indemnification rights.

The offering of Common Stock pursuant to the Sales Agreement will terminate upon termination of the Sales Agreement in accordance with its terms.

The foregoing description of the Sales Agreement is not complete and is qualified in its entirety by reference to the full text of the Sales Agreement, a copy of which is filed herewith as Exhibit 1.1 to this Current Report on Form 8-K and is incorporated herein by reference.

The opinion of Foley Hoag LLP regarding the Common Stock to be sold under the Sales Agreement is filed as Exhibit 5.1 hereto.

This Current Report on Form 8-K shall not constitute an offer to sell or the solicitation of an offer to buy the Common Stock discussed herein, nor shall there be any offer, solicitation, or sale of common stock in any state in which such offer, solicitation or sale would be unlawful prior to registration or qualification under the securities laws of any such state