GlobeNewswire Inc | Nov 16, 2020 04:01PM EST

November 16, 2020

Cash balance of $370.7 million as of September 30, 2020 bolstered by July IPO Recently expanded ANX005 clinical program into neurodegeneration, with initiation of Phase 2 in Huntingtons Disease Fully enrolled Phase 1b DDI trial in Guillain-Barr Syndrome

SOUTH SAN FRANCISCO, Calif., Nov. 16, 2020 (GLOBE NEWSWIRE) -- Annexon, Inc.(Annexon) (Nasdaq: ANNX), a clinical-stage biopharmaceutical company developing a pipeline of novel therapies for patients with classical complement-mediated disorders of the brain, body and eye, today announced third quarter 2020 financial results and recent business highlights.

We continue to make strong progress across our classical complement platform, including expanded development of ANX005 in Huntingtons Disease, and advancement of our subcutaneous formulation, ANX009, into the clinic, said Douglas Love, Esq., president and chief executive officer of Annexon. Our unique focus on C1q allows us to address a diverse set of classical complement-mediated autoimmune and neurodegenerative diseases, and were well capitalized to conduct several promising near- and mid-term Phase 2 clinical trials in these devastating diseases.

Program Highlights

-- Initiated Phase 2 trial evaluating ANX005 in Huntingtons Disease (HD). Initiated patient dosing in a Phase 2 trial designed to assess safety, tolerability, and biomarkers of target engagement and impact on neurodegeneration -- Initiated Phase 1 first-in-human trial of ANX009. Initiated subcutaneous dosing of healthy volunteers with Annexons third clinical-stage drug candidate in a Phase 1 trial designed to assess safety, tolerability, pharmacokinetics and pharmacodynamics of single and multiple ascending doses -- Completed enrollment of Guillain-Barr Syndrome (GBS) Drug-Drug Interaction (DDI) trial. Fully enrolled global Phase 1b DDI trial assessing safety and potential pharmacokinetic effect of ANX005 co-administered with IVIg in GBS patients. Data are anticipated in early 2021

Anticipated Upcoming Milestones

-- ANX005, a clinical-stage investigational monoclonal antibody intended to treat patients with complement-mediated disorders-- Phase 2 trial in patients with HD is ongoing with initial data anticipated in 2H 2021-- Phase 2/3 trial in patients with GBS is planned to initiate in early 2021 with data anticipated in 2023-- Phase 2 trial in patients with amyotrophic lateral sclerosis (ALS) is planned to initiate in early 2021 with initial data anticipated in 2H 2021-- Phase 2 trial in patients with warm autoimmune hemolytic anemia (wAIHA) is planned to initiate in early 2021 with initial data anticipated in 1H 2022 -- ANX007, a clinical-stage investigational monoclonal antibody Fab for the treatment of patients with complement-mediated neurodegenerative ophthalmic diseases-- Phase 2 trial in patients with geographic atrophy (GA) is planned to initiate in early 2021 with data anticipated in 2023 -- ANX009, a clinical-stage investigational, subcutaneous formulation of an antigen-binding fragment (Fab) intended to treat systemic antibody-mediated autoimmune diseases-- Phase 1 first-in-human trial is ongoing with data anticipated in 1H 2021

Third Quarter 2020 Financial Results

-- Cash and cash equivalents: Cash and cash equivalents were $370.7 million as of September 30, 2020 compared to $43.9 million as of December 31, 2019. In July 2020, Annexon completed an upsized IPO of 14,750,000 shares of its common stock, including the exercise of the underwriters option to purchase an additional 2,139,403 shares of common stock, resulting in net proceeds of $262.4 million, after deducting underwriting commissions and offering expenses -- Research and development (R&D) expenses: R&D expenses were $11.8 million for the quarter ended September 30, 2020 compared to $7.1 million for the quarter ended September 30, 2019 -- General and administrative (G&A) expenses: G&A expenses were $3.8 million for the quarter ended September 30, 2020 compared to $2.0 million for the quarter ended September 30, 2019 -- Net loss: Net loss was $15.6 million for the quarter ended September 30, 2020 compared to $10.2 million for the quarter ended September 30, 2019. Net loss attributable to common stockholders was $22.0 million or $0.77 per share for the quarter ended September 30, 2020 compared to $10.5 million or $24.14 per share for the quarter ended September 30, 2019

About Annexon, Inc.Annexon is a clinical-stage biopharmaceutical company developing a pipeline of novel therapies for patients with classical complement-mediated disorders of the brain, body and eye. The companys pipeline is based on its platform technology addressing well-researched classical complement-mediated autoimmune and neurodegenerative disease processes, both of which are triggered by aberrant activation of C1q, the initiating molecule of the classical complement pathway. Annexon is deploying a disciplined, biomarker-driven development strategy designed to establish that its product candidates are engaging the target at a well-tolerated therapeutic dose in the intended tissue compartments. For more information, visitwww.annexonbio.com.

Forward Looking StatementsThis press release contains forward-looking statements within the meaning of Section 27A of the Securities Act of 1933, as amended, and Section 21E of the Securities Exchange Act of 1934, as amended. In some cases, you can identify forward-looking statements by terminology such as aim, anticipate, assume, believe, contemplate, continue, could, design, due, estimate, expect, goal, intend, may, objective, plan, positioned, potential, predict, seek, should, target, will, would and other similar expressions that are predictions of or indicate future events and future trends, or the negative of these terms or other comparable terminology. All statements other than statements of historical facts contained in this press release are forward-looking statements. These forward-looking statements include, but are not limited to, statements about: advancement of the companys clinical and preclinical programs; the companys capital position and ability to conduct promising near- and mid-term Phase 2 clinical trials; timing and commencement of future nonclinical studies and clinical trials and research and development programs; and the implementation of the companys business model and strategic plans for its business and product candidates, including additional indications which the company may pursue. Forward-looking statements are not guarantees of future performance and are subject to risks and uncertainties that could cause actual results and events to differ materially from those anticipated, including, but not limited to, risks and uncertainties related to: the companys history of net operating losses; the companys ability to obtain necessary capital to fund its clinical programs; the early stages of clinical development of the companys product candidates; the effects of COVID-19 or other public health crises on the companys clinical programs and business operations; the companys ability to obtain regulatory approval of and successfully commercialize its product candidates; any undesirable side effects or other properties of the companys product candidates; the companys reliance on third-party suppliers and manufacturers; the outcomes of any future collaboration agreements; and the companys ability to adequately maintain intellectual property rights for its product candidates. These and other risks are described in greater detail under the section titled Risk Factors contained in the companys Quarterly Report on Form 10-Q for the quarterly period ended September 30, 2020 filed with the Securities and Exchange Commission (SEC) on November 16, 2020 pursuant to Rule 424(b) under the Securities Act and the companys other filings with the SEC. Any forward-looking statements that the company makes in this press release are made pursuant to the Private Securities Litigation Reform Act of 1995, as amended, and speak only as of the date of this press release. Except as required by law, the company undertakes no obligation to publicly update any forward-looking statements, whether as a result of new information, future events or otherwise.

ANNEXON, INC.Condensed Consolidated Statements of Operations(in thousands, except share and per share amounts)(Unaudited)

Three Months Ended Nine Months Ended September30, September30, 2020 2019 2020 2019 Operating expenses: Research and $ 11,775 $ 7,089 $ 31,279 $ 17,729 development (1)General and 3,810 1,981 8,999 5,660 administrative (1)Total operating 15,585 9,070 40,278 23,389 expensesLoss from operations (15,585 ) (9,070 ) (40,278 ) (23,389 )Loss on remeasurementof redeemable ? (1,340 ) ? (5,670 )convertible preferredstockliabilityOther (expense) (52 ) 224 64 821 income, netNet loss before taxes (15,637 ) (10,186 ) (40,214 ) (28,238 )Provision for income 1 2 5 3 taxesNet loss (15,638 ) (10,188 ) (40,219 ) (28,241 )Accretion onredeemable convertible (145 ) (281 ) (705 ) (815 )preferred stockDeemed dividend ?beneficial conversionfeature on (6,219 ) ? (6,219 ) ? redeemableconvertiblepreferred stockNet loss attributable $ (22,002 ) $ (10,469 ) $ (47,143 ) $ (29,056 )to common stockholdersNet loss per shareattributable to common $ (0.77 ) $ (24.14 ) $ (4.79 ) $ (67.04 )stockholders, basicanddilutedWeighted-averageshares used incomputing net loss pershare 28,465,156 433,749 9,845,754 433,406 attributable to commonstockholders, basicand diluted (1) Includes thefollowing stock-based compensationexpense:Research and 624 159 1,284 391 developmentGeneral and 847 451 1,613 1,122 administrative

ANNEXON, INC.Condensed Consolidated Balance Sheets(in thousands)(Unaudited)

September30, December31, 2020 2019Assets Current assets: Cash and cash equivalents $ 370,686 $ 43,931 Prepaid expenses and other current assets 2,889 1,475 Total current assets 373,575 45,406 Property and equipment, net 2,039 2,138 Other long-term assets ? 2,354 Total assets $ 375,614 $ 49,898 Liabilities, Redeemable Convertible Preferred Stock and Stockholders? Equity(Deficit)Current liabilities: Accounts payable $ 3,954 $ 2,371 Accrued liabilities 4,649 2,194 Deferred rent, current 385 366 Total current liabilities 8,988 4,931 Deferred rent 1,147 1,437 Total liabilities 10,135 6,368 Redeemable convertible preferred stock ? 143,984 Stockholders? Equity (Deficit): Preferred stock ? ? Common stock 38 4 Additional paid-in capital 508,318 2,202 Accumulated other comprehensive loss (78 ) (80 )Accumulated deficit (142,799 ) (102,580 )Total stockholders? equity (deficit) 365,479 (100,454 )Total liabilities, redeemable convertiblepreferred stock and stockholders?equity $ 375,614 $ 49,898 (deficit)

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