Annexon, Inc.

Previous wording

We are a biopharmaceutical company advancing the next generation platform of targeted immunotherapies aimed at complement-mediated neuroinflammatory diseases that impact nearly 10 million people worldwide. Building on more than a decade of expertise stopping acute and chronic neuroinflammation at its source, we have demonstrated robust target engagement in the body, brain and eye, and clinical proof of concept in multiple diseases.

Current wording

We are a biopharmaceutical company advancing the next generation platform of targeted immunotherapies aimed at complement-mediated neuroinflammatory diseases that collectively impact nearly 10 million people worldwide. Building on more than a decade of expertise stopping acute and chronic neuroinflammation at its source, we have demonstrated robust target engagement in the body, brain and eye, and clinical proof of concept in multiple diseases.

Previous wording

Tanruprubart is an investigational targeted immunotherapy delivered in a single infusion to rapidly halt aggressive neuroinflammation and damage in GBS, an acute, rare, neuromuscular emergency that annually affects ~150,000 people worldwide. There are currently no therapies approved by the FDA for GBS and no substantial evidence of effectiveness from the current standard of care. In the placebo-controlled Phase 3 trial, approximately 90% of GBS patients treated with tanruprubart improved by week 1 and more than twice as many treated patients achieved a normal state of health at week 26. Tanruprubart has consistently demonstrated rapid and sustained functional improvements across a comprehensive data package. We continue to engage with applicable EU and U.S. regulators to advance tanruprubart towards registration worldwide. Our Marketing Authorization Application, or MAA, filed with the European Medicines Agency, or EMA, in January 2026 for tanruprubart for the treatment of GBS is under review, and we continue to engage with EU regulators through the MAA review process. Tanruprubart has been granted orphan designation from the EMA. Tanruprubart has also been granted Fast Track and orphan drug designation for the treatment of GBS from the FDA. The currently ongoing open-label U.S./Europe FORWARD study is designed to broaden Western experience with tanruprubart, and we anticipate initial pharmacokinetics, or PK, pharmacodynamics, or PD, biomarker and functional data in 2026 to supplement our comprehensive data package for tanruprubart in GBS. Following such data, we plan to engage with the FDA with the goal of reaching alignment on our current and supplemental data package and information supporting the generalizability of tanruprubart in Western patients for submission of a biologics license application, or BLA, in 2026.

Current wording

Tanruprubart is an investigational targeted immunotherapy delivered in a single infusion to rapidly halt aggressive neuroinflammation and damage in GBS, an acute, rare, neuromuscular emergency that annually affects ~150,000 people worldwide. There are currently no therapies approved by the FDA for GBS and no substantial evidence of effectiveness from the current standard of care. In the placebo-controlled Phase 3 trial, approximately 90% of GBS patients treated with tanruprubart improved by week 1 and more than twice as many treated patients achieved a normal state of health at week 26. Tanruprubart has consistently demonstrated rapid and sustained functional improvements across a comprehensive data package. We continue to engage with applicable EU and U.S. regulators to advance tanruprubart towards registration worldwide. Our Marketing Authorization Application, or MAA, filed with the European Medicines Agency, or EMA, in January 2026 for tanruprubart for the treatment of GBS is under review, and we continue to engage with EU regulators through the MAA review process. Tanruprubart has been granted orphan designation from the EMA. Tanruprubart has also been granted Fast Track and orphan drug designation for the treatment of GBS from the FDA.

Previous wording

≥15-letter loss at any two consecutive visits through month 15. A secondary endpoint is EZ loss, which is a key anatomic measure of photoreceptor health and function. We plan to report topline data in the fourth quarter of 2026. We have established a global registration path with the FDA and EMA, which supports the potential of vonaprument to be the first treatment approved in both Europe and the U.S. for the protection of vision in patients with GA. The single-study program will be analyzed as two sub-studies in the U.S. in accordance with the FDA’s two-trial recommendation. Vonaprument is the first and only therapeutic candidate for the treatment of GA to receive Priority Medicine, or PRIME, designation by the EMA, which provides early and proactive support to developers of promising medicines that may offer a major therapeutic advantage over existing treatments or benefit to patients without treatment options. Vonaprument was also selected by the EMA for the Product Development Coordinator Pilot launched in July 2025 to help PRIME designation holders efficiently navigate regulatory interactions including expedited scientific advice, MAA submission readiness activities, and ad-hoc queries throughout the development program.

Current wording

In the ongoing global, sham-controlled, double-masked Phase 3 ARCHER II trial of 659 patients with GA, all eligible patients have received at least 12 months of vonaprument treatment, with masked event accrual in line with projections. ARCHER II retains strong statistical power and continues to be well-executed with a low discontinuation rate (<10%) and high compliance (>95%). We recently announced the expansion of the vonaprument Phase 3 program to add a Month 24 dual primary endpoint, complementing the current Month 15 primary endpoint, and to launch an open-label extension (OLE) study. With a dual primary endpoint strategy, ARCHER II can achieve success in protecting against vision loss at either Month 15 or Month 24, which are independent efficacy timepoints. The Month 15 primary endpoint remains on track for the fourth quarter of 2026. Upon completion of Month 24, all patients will have the option to receive monthly vonaprument treatment in the OLE study, designed to evaluate the longer-term profile of vonaprument for inclusion in the label. The primary endpoints of this two-year trial are the proportion of patients with confirmed BCVA ≥15-letter loss at two consecutive visits, measured through months 15 and 24. Secondary endpoints include safety, low luminance visual acuity and photoreceptor integrity. We have established a global registration path with the FDA and EMA, which supports the potential of vonaprument to be the first treatment approved in both Europe and the U.S. for the protection of vision in patients with GA. The single-study program will be analyzed as two sub-studies in the U.S. in accordance with the FDA’s two-trial recommendation. Vonaprument is the first and only therapeutic candidate for the treatment of GA to receive Priority Medicine, or PRIME, designation by the EMA, which provides early and proactive support to developers of promising medicines that may offer a major therapeutic advantage over existing treatments or benefit to patients without treatment options. Vonaprument was also selected by the EMA for the Product Development Coordinator Pilot launched in July 2025 to help PRIME designation holders efficiently navigate regulatory interactions including expedited scientific advice, MAA submission readiness activities, and ad-hoc queries throughout the development program.

Previous wording

ANX1502 is a novel oral small molecule inhibiting the activated form of C1s, an enzyme carried by C1q to initiate the classical cascade, which we believe is first-in-kind and has the potential to offer the advantages of selective upstream classical complement inhibition with the convenience and flexibility of oral administration. In a Phase 1 single-ascending dose and multiple-ascending dose clinical trial in healthy volunteers designed to evaluate the safety, tolerability, PK and PD, ANX1502 was generally well tolerated across cohorts with no serious adverse events, achieved target levels of active drug and showed supportive impact on a PD biomarker of complement activity. We are evaluating an enteric-coated tablet formulation of ANX1502 in an ongoing POC study in patients with cold agglutinin disease, or CAD. We have observed drug levels at and exceeding the pre-defined target in fasted CAD patients. Dosing is ongoing to enhance our understanding of ANX1502’s profile and we plan to provide an update upon study completion in 2026.

Current wording

ANX1502 is a novel oral small molecule inhibiting the activated form of C1s, an enzyme carried by C1q to initiate the classical cascade, which we believe is first-in-kind and has the potential to offer the advantages of selective upstream classical complement inhibition with the convenience and flexibility of oral administration. In a Phase 1 single-ascending dose and multiple-ascending dose clinical trial in healthy volunteers designed to evaluate the safety, tolerability, PK and PD, ANX1502 was generally well tolerated across cohorts with no serious adverse events, achieved target levels of active drug and showed supportive impact on a PD biomarker of complement activity. We are evaluating an enteric-coated tablet formulation of ANX1502 in an ongoing POC study in patients with cold agglutinin disease, or CAD. We have observed drug levels at and exceeding the pre-defined target in fasted CAD patients. Dosing is complete and we plan to provide an update on the POC study in the second half of 2026.

Previous wording

We were incorporated in March 2011 and commenced operations later that year. To date, we have focused primarily on performing research and development activities, hiring personnel and raising capital to support and expand these activities. We do not have any products approved for sale, and we have not generated any revenue from product sales. We have incurred net losses each year since our inception. Our net losses were $44.1 million and $54.4 million for the three months ended March 31, 2026 and 2025, respectively. As of March 31, 2026, we had an accumulated deficit of $961.5 million and cash and cash equivalents and short-term investments of $225.0 million.

Current wording

We were incorporated in March 2011 and commenced operations later that year. To date, we have focused primarily on performing research and development activities, hiring personnel and raising capital to support and expand these activities. We do not have any products approved for sale, and we have not generated any revenue from product sales. We have incurred net losses each year since our inception. Our net losses were $55.3 million and $49.2 million for the three months ended June 30, 2026 and 2025, respectively, and $99.5 million and $103.5 million for the six months ended June 30, 2026 and 2025, respectively. As of June 30, 2026, we had an accumulated deficit of approximately $1.0 billion and cash and cash equivalents and short-term investments of $209.2 million.

Previous wording

Research and development expenses decreased by $12.4 million, or 26%, for the three months ended March 31, 2026 compared to the same period in 2025. The change was primarily attributable to a decrease of $11.2 million in completed contract manufacturing activity for the tanruprubart European MAA filing as well as the vonaprument manufacturing technology transfer to a commercial-ready facility. Compensation and personnel-related expenses (including stock-based compensation) decreased by $2.4 million, reflecting lower headcount, and consulting and professional services expenses decreased by $1.9 million. In addition, direct clinical and nonclinical outside services costs increased by $3.4 million associated with the vonaprument Phase 3 ARCHER II trial in GA and the ongoing tanruprubart FORWARD study in GBS.

Current wording

Research and development expenses increased by $2.4 million, or 6%, for the three months ended June 30, 2026 compared to the same period in 2025. The change was primarily attributable to an increase of $6.0 million in contract manufacturing activity for the manufacturing technology transfer of vonaprument to a commercial-ready facility. Consulting and professional services expenses decreased by $1.4 million, following the MAA submission for tanruprubart in January 2026. Compensation and personnel-related expenses (including stock-based compensation) decreased by $1.3 million, reflecting lower headcount. In addition, direct clinical and nonclinical outside services costs decreased by $1.2 million primarily associated with the vonaprument Phase 3 ARCHER II trial in GA partially offset by higher tanruprubart FORWARD study costs.

Previous wording

General and administrative expenses increased by $1.0 million, or 11%, for the three months ended March 31, 2026 compared to the same period in 2025, primarily driven by a $1.2 million increase in consulting and professional services costs for corporate affairs activity across our portfolio.

Current wording

General and administrative expenses increased by $3.1 million, or 41%, for the three months ended June 30, 2026 compared to the same period in 2025, primarily driven by a $2.3 million increase in consulting and professional services costs for corporate affairs activities across our portfolio. In addition, compensation and personnel-related expenses were higher primarily due to stock-based compensation expense.

Previous wording

Interest and other income, net, decreased by $1.1 million, or 37%, for the three months ended March 31, 2026 compared to the same period in 2025. The decrease was primarily due to lower average cash and investment balances.

Current wording

Interest and other income, net, decreased by $0.7 million, or 27%, for the three months ended June 30, 2026 compared to the same period in 2025. The decrease was primarily due to lower average cash and investment balances.

Previous wording

To date, we have funded our operations primarily through the sale of equity securities including, most recently in November 2025, the public offering of approximately $86.3 million of common stock and pre-funded warrants. In addition, on March 30, 2026, we entered into a sales agreement with TD Cowen, or the 2026 Sales Agreement, pursuant to which we may offer and sell, from time to time through TD Cowen, at our option, shares of our common stock having an aggregate offering price of up to $150.0 million. As of March 31, 2026, we had available cash and cash equivalents and short-term investments of $225.0 million and an accumulated deficit of $961.5 million.

Current wording

To date, we have funded our operations primarily through the sale of equity securities including, most recently in November 2025, the public offering of approximately $86.3 million of shares of common stock and pre-funded warrants. In addition, on March 30, 2026, we entered into a sales agreement with TD Cowen pursuant to which we may offer and sell, from time to time through TD Cowen, at our option, shares of our common stock having an aggregate offering price of up to $150.0 million. As of June 30, 2026, we had available cash and cash equivalents and short-term investments of $209.2 million and an accumulated deficit of approximately $1.0 billion.

Previous wording

Cash used in operating activities for the three months ended March 31, 2026 was $46.8 million, which consisted of a net loss of $44.1 million, and a net change of $7.1 million in our operating assets and liabilities, partially offset by $4.4 million in non-cash charges. The non-cash charges consisted of stock-based compensation of $4.2 million, depreciation and amortization of $0.5 million, and a reduction in the carrying amount of right-of-use assets of $0.4 million, partially offset by accretion of discount on available-for-sale securities of $0.6 million.

Current wording

Cash used in operating activities for the six months ended June 30, 2026 was $94.8 million, which consisted of a net loss of $99.5 million and a net change of $5.3 million in our operating assets and liabilities, partially offset by $10.0 million in non-cash charges. The non-cash charges consisted of stock-based compensation of $9.0 million, depreciation and amortization of $1.1 million, and a reduction in the carrying amount of right-of-use assets of $0.8 million, partially offset by accretion of discount on available-for-sale securities of $0.9 million.

Previous wording

Cash used in operating activities for the three months ended March 31, 2025 was $50.1 million, which consisted of a net loss of $54.4 million, partially offset by $4.1 million in non-cash charges and a net change of $0.2 million in our operating assets and liabilities. The non-cash charges consisted of stock-based compensation of $5.1 million, depreciation and amortization of $0.5 million and a reduction in the carrying amount of right-of-use assets of $0.4 million, partially offset by accretion of discount on available-for-sale securities of $1.9 million.

Current wording

Cash used in operating activities for the six months ended June 30, 2025 was $88.1 million, which consisted of a net loss of $103.5 million, partially offset by $8.0 million in non-cash charges and a net change of $7.4 million in our operating assets and liabilities. The non-cash charges consisted of stock-based compensation of $9.3 million, depreciation and amortization of $1.1 million and a reduction in the carrying amount of right-of-use assets of $0.7 million, partially offset by accretion of discount on available-for-sale securities of $3.1 million.

Previous wording

Cash provided by investing activities for the three months ended March 31, 2025 was $97.6 million, which consisted of $159.5 million of proceeds from maturities of available-for-sale securities, partially offset by $61.8 million of purchases of available-for-sale securities and $0.1 million of purchases of property and equipment.

Current wording

Cash provided by investing activities for the six months ended June 30, 2026 was $67.0 million, which consisted of $83.0 million of proceeds from maturities of available-for-sale securities, partially offset by $15.9 million of purchases of available-for-sale securities and $0.1 million of purchases of property and equipment.

Previous wording

Cash provided by investing activities for the three months ended March 31, 2026 was $27.1 million, which consisted of $33.0 million of proceeds from maturities of available-for-sale securities, partially offset by $5.9 million of purchases of available-for-sale securities.

Current wording

Cash provided by investing activities for the six months ended June 30, 2025 was $170.7 million, which consisted of $291.3 million of proceeds from maturities of available-for-sale securities, partially offset by $120.5 million of purchases of available-for-sale securities and $0.1 million of purchases of property and equipment.

Previous wording

Cash provided by financing activities for the three months ended March 31, 2026 was $32.9 million, which consisted of $32.7 million of net proceeds from the issuance of common stock under our 2024 ATM program and $0.2 million of net proceeds from the exercise of common stock options and employee stock purchase plan purchases.

Current wording

Cash provided by financing activities for the six months ended June 30, 2026 was $65.0 million, which consisted of $63.8 million of net proceeds from the aggregate issuance of common stock under our 2024 ATM program and 2026 ATM program and $1.3 million of net proceeds from the exercise of common stock options and employee stock purchase plan purchases.

Previous wording

Cash provided by financing activities for the three months ended March 31, 2025 was $0.1 million, which consisted of $0.1 million of proceeds from the exercise of common stock options.

Current wording

Cash provided by financing activities for the six months ended June 30, 2025 was $0.2 million, which consisted of proceeds from the exercise of common stock options and employee stock purchase plans.

Previous wording

Based upon our current operating plan, we believe that our existing cash and cash equivalents and short-term investments will enable us to fund operating expenses into the second half of 2027. We will require substantial additional financing to achieve our goals, and a failure to obtain this necessary capital when needed on acceptable terms, or at all, could force us to delay, limit, reduce or terminate our product development programs, commercialization efforts or other operations. We have based this estimate on assumptions that may prove to be wrong, and we could utilize our available capital resources sooner than we expect. We will be required to seek additional funding in the future until such time, if ever, as we can generate substantial product revenue, and currently intend to do so through public or private equity offerings or debt financings, credit or loan facilities, collaborations or a combination of one or more of these funding sources. We may also need to seek additional funds sooner than planned as result of changes in our development plans and regulatory requirements to support registration of our product candidates. Additional funds may not be available to us on acceptable terms or at all. If we fail to obtain necessary capital when needed on acceptable terms, or at all, we could be forced to delay, limit, reduce or terminate our product development programs, commercialization efforts or other operations. If we raise additional funds by issuing equity securities, our stockholders will suffer dilution and the terms of any financing may adversely affect the rights of our stockholders. In addition, as a condition to providing additional funds to us, future investors may demand, and may be granted, rights superior to those of existing stockholders. Debt financing, if available, is likely to involve restrictive covenants limiting our flexibility in conducting future business activities, and, in the event of insolvency, debt holders would be repaid before holders of our equity securities received any distribution of our corporate assets.

Current wording

Based upon our current operating plan, we believe that our existing cash and cash equivalents and short-term investments will enable us to fund operating expenses into 2028. We will require substantial additional financing to achieve our goals, and a failure to obtain this necessary capital when needed on acceptable terms, or at all, could force us to delay, limit, reduce or terminate our product development programs, commercialization efforts or other operations. We have based this estimate on assumptions that may prove to be wrong, and we could utilize our available capital resources sooner than we expect. We will be required to seek additional funding in the future until such time, if ever, as we can generate substantial product revenue, and currently intend to do so through public or private equity offerings or debt financings, credit or loan facilities, collaborations or a combination of one or more of these funding sources. We may also need to seek additional funds sooner than planned as result of changes in our development plans and regulatory requirements to support registration of our product candidates. Additional funds may not be available to us on acceptable terms or at all. If we fail to obtain necessary capital when needed on acceptable terms, or at all, we could be forced to delay, limit, reduce or terminate our product development programs, commercialization efforts or other operations. If we raise additional funds by issuing equity securities, our stockholders will suffer dilution and the terms of any financing may adversely affect the rights of our stockholders. In addition, as a condition to providing additional funds to us, future investors may demand, and may be granted, rights superior to those of existing stockholders. Debt financing, if available, is likely to involve restrictive covenants limiting our flexibility in conducting future business activities, and, in the event of insolvency, debt holders would be repaid before holders of our equity securities received any distribution of our corporate assets.

Previous wording

In June 2024, we raised net proceeds of approximately $116.8 million after deducting underwriting discounts and offering expenses through the sale of 13,001,120 shares of our common stock at a price of $6.25 per share and pre-funded warrants to purchase an aggregate of 7,000,000 shares of common stock at a price of $6.249 per share, which equals the per share offering price for the shares of common stock less the $0.001 exercise price for each pre-funded warrant. In March 2026, we issued an aggregate of 4,499,124 shares of common stock upon the cashless exercise of pre-funded warrants to purchase 4,500,000 shares of common stock.

Current wording

In June 2024, we raised net proceeds of approximately $116.8 million after deducting underwriting discounts and offering expenses through the sale of 13,001,120 shares of our common stock at a price of $6.25 per share and pre-funded warrants to purchase an aggregate of 7,000,000 shares of common stock at a price of $6.249 per share, which equals the per share offering price for the shares of common stock less the $0.001 exercise price for each pre-funded warrant.

Previous wording

In December 2023, we raised net proceeds of approximately $117.0 million after deducting underwriting discounts and offering expenses through the sale of 25,035,000 shares of our common stock at a price of $2.880 per share and pre-funded warrants to purchase an aggregate of 18,379,861 shares of common stock at a price of $2.879 per share, which equals the per share offering price for the shares of common stock less the $0.001 exercise price for each pre-funded warrant. In March 2026, we issued an aggregate of 2,027,384 shares of common stock upon the cashless exercise of pre-funded warrants to purchase 2,027,778 shares of common stock.

Current wording

In December 2023, we raised net proceeds of approximately $117.0 million after deducting underwriting discounts and offering expenses through the sale of 25,035,000 shares of our common stock at a price of $2.880 per share and pre-funded warrants to purchase an aggregate of 18,379,861 shares of common stock at a price of $2.879 per share, which equals the per share offering price for the shares of common stock less the $0.001 exercise price for each pre-funded warrant.

Previous wording

In June 2025, we and holders of common warrants exercisable for 6,877,622 shares of our common stock entered into amendments to the common warrants held by such holders. The amendments extended the term of the common warrants by one year until June 30, 2026, and removed the cashless exercise option. If all such common warrants are exercised in full for cash (without regard to any applicable ownership limitations), we would receive aggregate gross proceeds of approximately $39.9 million. The remaining common warrants to purchase 1,226,993 shares of our common stock not subject to these amendments expired unexercised on June 30, 2025.

Current wording

In June 2025, we and holders of common warrants exercisable for 6,877,622 shares of our common stock entered into amendments to the common warrants held by such holders. The amendments extended the term of the common warrants by one year until June 30, 2026, and removed the cashless exercise option. If all such common warrants are exercised in full for cash (without regard to any applicable ownership limitations), we would receive aggregate gross proceeds of approximately $39.9 million. The remaining common warrants to purchase 1,226,993 shares of our common stock not subject to these amendments expired unexercised on June 30, 2025. On June 30, 2026, the amended common warrants to purchase 6,877,622 shares of our common stock expired unexercised.

Previous wording

The following summarizes warrant activity during the three months ended March 31, 2026 and 2025:

Current wording

The following summarizes warrant activity during the six months ended June 30, 2026 and 2025:

Previous wording

In March 2026, we entered into a sales agreement with TD Securities (USA) LLC, or TD Cowen, as sales agent, pursuant to which we may offer and sell, from time to time through TD Cowen, at our option, shares of our common stock having an aggregate offering price of up to $150.0 million, or the 2026 ATM program. We agreed to pay TD Cowen a commission of up to 3.0% of the aggregate gross proceeds for the common stock sold through the 2026 ATM program. During the three months ended March 31, 2026, no sales were made under the 2026 ATM program. Subsequent to March 31, 2026 and through the date of issuance of these interim unaudited condensed consolidated financial statements, we sold 1,305,463 shares of common stock under the 2026 ATM program for net proceeds of approximately $8.1 million, after deducting commissions paid to TD Cowen.

Current wording

In March 2026, we entered into a sales agreement with TD Securities (USA) LLC, or TD Cowen, as sales agent, pursuant to which we may offer and sell, from time to time through TD Cowen, at our option, shares of our common stock having an aggregate offering price of up to $150.0 million, or the 2026 ATM program. We agreed to pay TD Cowen a commission of up to 3.0% of the aggregate gross proceeds for the common stock sold through the 2026 ATM program. During the six months ended June 30, 2026, we sold 5,734,361 shares of common stock under the 2026 ATM program for net proceeds of approximately $31.0 million, after deducting commissions paid to TD Cowen and other offering costs. As of June 30, 2026, approximately $117.8 million remained available under the 2026 ATM program.

Previous wording

In March 2024, we entered into a sales agreement with TD Cowen, as sales agent, or 2024 ATM program, pursuant to which we could issue and sell shares of our common stock for an aggregate maximum offering of $100.0 million. During the three months ended March 31, 2026, we sold 6,049,762 shares of our common stock under the 2024 ATM program for net proceeds of approximately $32.7 million, after deducting commissions paid to TD Cowen and other offering costs. Approximately $33.3 million remained available under the 2024 ATM program, which we terminated in May 2026.

Current wording

In March 2024, we entered into a sales agreement with TD Cowen, as sales agent, pursuant to which we were permitted to offer and sell shares of our common stock having an aggregate maximum offering price of up to $100.0 million, or 2024 ATM program. During the six months ended June 30, 2026, we sold 6,049,762 shares of our common stock under the 2024 ATM program for net proceeds of approximately $32.7 million, after deducting commissions paid to TD Cowen and other offering costs. No sales were made under the 2024 ATM program during the six months ended June 30, 2025. In May 2026, we terminated the 2024 ATM program. Approximately $33.3 million remained available under the 2024 ATM program at the time of termination; however, no further shares of common stock may be sold under the 2024 ATM program.