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Public and Registered Direct Offerings

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On May 15, 2025, the Company entered into an underwriting agreement (the “Underwriting Agreement”) with several underwriters for the sale of 5,000,000 shares of its common stock (the “Public Offering”), at a public offering price of $10.00 per share (the “Public Offering Price”). Under the terms of the Underwriting Agreement, the Company also granted the underwriters a 30-day option to purchase up to an additional 750,000 shares of common stock at the

Public Offering Price, which the underwriters exercised in full. The Company received aggregate gross proceeds from the Public Offering of $57.5 million. The Company also entered into a securities purchase agreement with Abbott Laboratories (“Abbott”) pursuant to which the Company agreed to issue and sell 2,026,963 shares of its common stock substantially concurrently with the Public Offering, at the Public Offering Price, to Abbott for an aggregate purchase price of approximately $20.3 million in a private placement (the “Private Placement”). The Public Offering and Private Placement closed on May 19, 2025 and May 20, 2025, respectively, and the Company received net proceeds of approximately $52.1 million and $20.1 million, respectively, after deducting underwriting discount, commissions, and offering expenses.

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On April 30, 2026, the Company entered into an underwriting agreement (the “April 2026 Underwriting Agreement”) with TD Securities (USA) LLC and Barclays Capital Inc., as representatives of the several underwriters named therein, pursuant to which the Company agreed to issue and sell an aggregate of 8,000,000 shares of Common Stock and 8,000,000 pre-funded warrants, each representing the right to purchase one share of Common Stock at an exercise price of $0.001 per share (the “May 2026 Pre-Funded Warrants”), at a price to the public of $5.00 per share (or $4.999 per May 2026 Pre-Funded Warrant) (the “May 2026 Offering”). Under the terms of the April 2026 Underwriting Agreement, the Company also granted the underwriters an option, exercisable for 30 days, to purchase up to an additional 2,400,000 shares of Common Stock. The May 2026 Offering closed on May 4, 2026, and the underwriters exercised in full their option to purchase 2,400,000 additional shares of Common Stock. In the aggregate, the Company sold 10,400,000 shares of Common Stock and 8,000,000 May 2026 Pre-Funded Warrants, with aggregate gross proceeds to the Company of approximately $92.0 million, before deducting underwriting discounts and commissions and offering expenses payable by the Company. The net proceeds to the Company were approximately $86.0 million, after deducting underwriting discounts and commissions and estimated offering expenses payable by the Company.

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ATM Offerings

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On August 6, 2025, the Company entered into an at-the-market sales agreement (the “Sales Agreement”) with TD Securities (USA) LLC (“TD Cowen”), under which the Company could offer and sell, from time to time, at its sole discretion, shares of its common stock having an aggregate offering price of up to $100.0 million through TD Cowen as its sales agent in an “at the market” offering, or ATM offering. TD Cowen will receive commissions up to 3.0% of the gross proceeds of any common stock sold through TD Cowen under the Sales Agreement. The shares were offered and sold pursuant to an effective shelf registration statement on Form S-3, which was originally filed with the Securities and Exchange Commission on August 6, 2025. During the six months ended June 30, 2026, the Company received approximately $6.2 million in proceeds from the sale of 892,380 shares under the Sales Agreement, after deducting sales commissions and offering expenses.

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In August 2023, the Company entered into an Equity Distribution Agreement (the “Equity Distribution Agreement”) with Goldman Sachs & Co. LLC (“GS”), under which the Company could offer and sell, from time to time, at its sole discretion, shares of its common stock having an aggregate offering price of up to $106.6 million through GS as its sales agent in an “at the market” offering. GS received commissions up to 3.0% of the gross proceeds of any common stock sold through GS under the Equity Distribution Agreement. The shares were offered and sold pursuant to an effective shelf registration statement on Form S-3, which was originally filed with the Securities and Exchange Commission on August 10, 2023. On October 24, 2024, the Company amended the Equity Distribution Agreement with GS to reduce the maximum amount of shares issuable thereunder to $55.0 million. On May 15, 2025, in connection with the Public Offering and Private Placement, the Equity Distribution Agreement was terminated. At the time of termination of the Equity Distribution Agreement on May 15, 2025, the Company had received approximately $30.8 million in net proceeds from the sale of 2,006,528 shares under the Equity Distribution Agreement, after deducting sales commissions and offering expenses.

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Stock Purchase Warrants

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The table below summarizes the warrant activity for the six months ended June 30, 2026 (in thousands). This table does not include the PHC Exchange Warrant (as defined below) or the PHC Purchase Warrant (as defined and described below). Such warrants are pre-funded and excluded from the table due to their nominal exercise price of $0.02 per warrant share.

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On June 30, 2016, we entered into a loan agreement with Oxford Finance and Silicon Valley Bank (collectively, the “Lenders”) and issued to the Lenders 10-year stock purchase warrants to purchase an aggregate of 5,830, 3,152 and 4,033 shares of common stock at an exercise price of $77.20, $47.60 and $37.20 per share, respectively (“Oxford/SVB Warrants”). The Oxford/SVB Warrants expire on June 30, 2026, November 22, 2026 and March 29, 2027, respectively.

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On March 13, 2023, we issued and sold to PHC a warrant to purchase 771,288 shares of common stock for $15.0 million (the “Purchase Warrant”). The Purchase Warrant is a “pre-funded” warrant with a nominal exercise price of $0.02 per share. All or any part of the Purchase Warrant is exercisable by PHC at any time and from time to time.

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In March 2023, we entered into an exchange agreement with PHC, pursuant to which PHC exchanged $35.0 million aggregate principal amount of convertible notes due October 31, 2024, including all accrued and unpaid interest thereon, for a warrant (the “PHC Exchange Warrant”) to purchase up to 3,426,266 shares of common stock (the “PHC Exchange Warrant Shares”). The PHC Exchange Warrant is a “pre-funded” warrant with a nominal exercise price of $0.02 per PHC Exchange Warrant Share. All or any part of the PHC Exchange Warrant is exercisable by PHC at any time and from time to time.

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On September 8, 2023, we entered into the Loan and Security Agreement with several lenders and issued the Tranche 1 Warrants to acquire an aggregate of 41,619 shares of common stock at an initial exercise price of $12.01 per share. The Tranche 1 Warrants may be exercised through the earlier of (i) September 8, 2030 and (ii) the consummation of certain acquisition transactions involving the company, as set forth in the warrant agreement. On September 3, 2025, the Company and the lenders entered into an amendment to reduce the exercise price to $9.09 per share. All other terms of the warrants, including the expiration date and number of shares issuable upon exercise, remain unchanged.

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On January 2, 2024, we issued the Tranche 2 Warrants to acquire an aggregate of 17,395 shares at an initial exercise price of $11.50 per share. The Tranche 2 Warrants may be exercised through the earlier of (i) January 2, 2031 and (ii) the consummation of certain acquisition transactions involving the company, as set forth in the warrant agreement. On September 3, 2025, the Company and the lenders entered into an amendment to reduce the exercise price to $9.09 per share. All other terms of the warrants, including the expiration date and number of shares issuable upon exercise, remain unchanged.

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On October 24, 2024, in connection with a registered direct securities offering, the Company issued to the investors in the offering warrants to purchase an aggregate of 2,285,714 shares of common stock at an exercise price of $7.00 per share. The warrants were non-exercisable for the first six months after issuance and expire on April 29, 2030.

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On May 6, 2026, we executed the Second Amendment to the Amended Loan and Security Agreement with several lenders and issued the 2026 Warrants to acquire an aggregate of 79,732 shares of common stock at an initial exercise price of $5.0167 per share. The 2026 Warrants may be exercised through the earlier of (i) May 6, 2033 and (ii) the consummation of certain acquisition transactions involving the company, as set forth in the warrant agreement.