Summit Therapeutics Establishes $380 Million At-the-Market Offering Program with J.P. Morgan Securities

Distribution Agreement Terms and Operational Framework

Summit Therapeutics has authorized J.P. Morgan Securities LLC to act as its exclusive sales agent under the new distribution agreement, which became effective on July 23, 2026. Under the terms of the arrangement, the sales agent is permitted to sell shares of Summit's common stock at prevailing market prices, at prices related to prevailing market prices, or at negotiated prices, depending on market conditions and the company's preferences. The sales agent will employ commercially reasonable efforts consistent with its normal trading and sales practices to facilitate share sales based on instructions provided by Summit, including any price, time, size limits, or other customary parameters specified by the company.

The structure of the distribution agreement affords Summit significant operational control over the capital raise process. The company retains the right to establish specific conditions for each offering, including minimum price thresholds, maximum daily or weekly volumes, and timing windows during which sales may or may not occur. Summit may also suspend solicitations and offers under the agreement at any time without penalty or obligation to provide advance notice. This flexibility is characteristic of at-the-market offerings, which allow companies to access capital markets gradually rather than through a single, fixed-price public offering.

Aggregate Offering Size and Commission Structure

The distribution agreement authorizes Summit to offer and sell shares with an aggregate offering price of up to $380 million. This maximum authorized amount does not represent a commitment by the company to raise the full sum; rather, it establishes the ceiling for potential capital that may be accessed through at-the-market transactions over the term of the agreement. The company disclosed that it is under no obligation to sell any shares under the Distribution Agreement and may elect to raise significantly less than the authorized amount or none at all, depending on evolving business circumstances and market conditions.

J.P. Morgan Securities LLC will receive a commission of up to 3.0% of the gross sales price per share sold in its capacity as sales agent. This commission rate is standard for at-the-market offerings and represents the primary economic benefit to the sales agent for facilitating transactions. The company will bear this cost as a percentage of proceeds raised, effectively reducing the net capital received by Summit for each share sold. The commission structure incentivizes the sales agent to actively market and execute transactions while compensating it proportionally for successful sales activity.

Trading Mechanisms and Market Execution Methods

Shares sold under the distribution agreement may be executed through multiple methods and venues, providing flexibility in how transactions are completed. The sales agent is permitted to execute sales as ordinary brokers' transactions directly on the Nasdaq Global Market, where Summit's common stock is currently listed under the ticker symbol SMMT, or into other existing trading markets for the company's securities. This flexibility allows transactions to be routed to the venue offering the best execution for each individual sale, potentially minimizing market impact and achieving optimal pricing.

In addition to open market trading, the agreement permits sales through alternative execution methods including transactions with market makers, block trades involving larger positions, or negotiated transactions between the sales agent and qualified buyers. Block transactions allow the sales agent to accumulate and sell larger quantities of shares in single transactions to institutional investors, which can sometimes result in better pricing for the company when demand is sufficient. Negotiated transactions, meanwhile, enable the sales agent to discuss pricing and terms directly with sophisticated buyers, potentially allowing for tailored arrangements that benefit both parties.

Registration Statement and Prospectus Compliance

The offering of shares under the distribution agreement is conducted pursuant to Summit's effective Form S-3 registration statement, which was filed with the Securities and Exchange Commission on June 9, 2026, and automatically became effective upon filing. The Form S-3 is a streamlined registration statement available to companies meeting specified eligibility requirements, permitting them to register securities offerings more efficiently than through the longer Form S-1 process. Summit's eligibility to use Form S-3 indicates that the company meets SEC criteria regarding market capitalization, public float, or other financial thresholds required for this registration form category.

Summit filed a prospectus supplement with the SEC on July 23, 2026, the same date on which the distribution agreement was executed. This prospectus supplement provides investors with detailed information about the at-the-market offering, including information about Summit Therapeutics, its business operations, risk factors, use of proceeds if any shares are sold, and other material disclosures required by federal securities laws. The prospectus supplement, together with the base prospectus contained within the Form S-3 registration statement, constitutes the complete offering document that must be provided to prospective investors before they purchase shares through the distribution agreement.

Capital Raising Flexibility and Strategic Purpose

At-the-market offering programs provide biopharmaceutical companies like Summit with strategic flexibility in accessing capital markets without committing to a specific raise timeline or amount. Unlike traditional registered direct offerings or public offerings that require the company to identify a target raise amount and complete the transaction within a compressed timeframe, at-the-market programs permit companies to sell shares opportunistically as market conditions warrant. This approach can be advantageous for companies in capital-intensive industries such as therapeutics development, where capital needs may evolve as clinical programs advance or business priorities shift.

The $380 million authorization provides Summit with access to a meaningful capital reserve that can support operational expenditures, research and development activities, clinical trial expenses, potential acquisitions or partnerships, and general corporate purposes. Companies in the biopharmaceutical sector commonly establish at-the-market programs as part of a broader capital strategy that may also include other financing mechanisms such as debt issuance, collaboration agreements, or strategic partnerships. The ability to access up to $380 million in equity capital over time provides Summit with optionality in managing its balance sheet and funding its therapeutic pipeline development.

Legal Opinion and Documentation

Baker & Hostetler LLP, counsel to Summit Therapeutics, provided a legal opinion regarding the validity of the issuance and sale of the shares being offered pursuant to the distribution agreement. This opinion, filed as Exhibit 5.1 to the announcement, represents counsel's determination that the shares, when issued and sold under the distribution agreement, will be validly issued, fully paid, and non-assessable under Delaware law. The provision of such a legal opinion is a standard requirement in securities offerings and provides investors and underwriters with confidence regarding the legal standing of the securities being offered.

The legal documentation supporting the distribution agreement includes the complete text of the agreement itself, filed as Exhibit 1.1, which contains all terms, conditions, representations, warranties, and obligations of both Summit and J.P. Morgan Securities LLC. This documentation establishes the formal contract governing the relationship between the company and its sales agent and sets forth the specific procedures, restrictions, and indemnification provisions applicable to the offering. The filing of these exhibits with the SEC ensures that investors and other market participants have access to the underlying contractual terms governing the at-the-market program.

Absence of Obligation and Suspension Rights

A critical feature of the distribution agreement is that Summit is explicitly not obligated to sell any shares under the arrangement. This provision distinguishes at-the-market offerings from traditional underwritten public offerings, where the company commits to offering a specific number of shares or raising a specified amount of capital. Under the terms disclosed, Summit retains complete discretion regarding whether to initiate sales, the pace at which sales occur, and the timing of any sales activity. This flexibility protects the company from market pressure to complete a raise regardless of market conditions or internal circumstances.

Furthermore, Summit has the right to suspend solicitations and offers under the distribution agreement at any time. This suspension right allows the company to pause or halt sales activity if market conditions become unfavorable, if business circumstances change, if the company receives material non-public information requiring disclosure before resuming sales, or for any other reason determined by Summit's management. The ability to suspend activity without penalty or advance notice distinguishes at-the-market programs from firm commitment understandings and provides the company with valuable optionality during volatile or uncertain market periods.

Market Impact and Investor Considerations

At-the-market offerings can have varying effects on share price and market dynamics, depending on the pace and volume of share issuance, overall market sentiment toward the company, and the strength of underlying demand for the stock. Because shares are sold at prevailing market prices through ordinary trading mechanisms, the offering itself does not establish a fixed price for the entire offering amount, as would occur in a traditional underwritten offering. This approach may result in better pricing during periods of strong demand or periods when the stock is trading at relatively high valuations, while it may result in lower realization during weaker demand periods.

Investors should recognize that the existence of an at-the-market program represents potential future dilution to existing shareholders if and when the company elects to conduct sales under the agreement. The magnitude of dilution depends on the actual number of shares sold, the price at which they are sold, and the total outstanding share count at the time of issuance. While the company has no obligation to sell any shares, the authorization for up to $380 million in offerings creates the possibility of meaningful share issuance, and shareholders should monitor announcements regarding actual sales activity to assess the impact on their ownership percentage and earnings per share.

Regulatory Framework and Offering Structure Classification

The distribution agreement establishes sales that are classified as "at-the-market" offerings under Rule 415(a)(4) of the Securities Act of 1933, as amended. This regulatory classification identifies the offering as one conducted at prevailing market prices through ordinary trading mechanisms rather than through a fixed-price underwritten offering or negotiated transaction with specific investors. The at-the-market classification carries specific regulatory implications regarding pricing, execution, and disclosure requirements, all of which are satisfied by the registration statement and prospectus supplement filed with the SEC.

Summit's disclosure that share sales may be made through "ordinary brokers' transactions" directly on the Nasdaq Global Market reflects the company's commitment to executing sales through standard trading infrastructure rather than through negotiated block trades or private transactions that might command premium or discounted pricing. This approach promotes market efficiency and provides transparency to all market participants regarding the prices at which Summit shares are trading and the volumes being executed. The regulatory structure established under Rule 415(a)(4) ensures that pricing and execution adhere to ordinary market practices rather than being subject to special arrangements that might disadvantage other shareholders.