# EDGAR Filing Document

**Accession Number:** 0001528115
**File Stem:** 0001193125-25-280384
**Filing Date:** 2025-11
**Character Count:** 262804
**Document Hash:** ddbe02893d2e3bc2c832f13c8f111002
**Contains OCR:** False
**Source Format:** 

## Filing Content

## Filing Summary
**0001193125-25-280384.hdr.sgml**: 20251113

**ACCESSION NUMBER**: 0001193125-25-280384

**CONFORMED SUBMISSION TYPE**: 424B5

**PUBLIC DOCUMENT COUNT**: 3

**FILED AS OF DATE**: 20251113

**DATE AS OF CHANGE**: 20251113

**FILER**: 

**COMPANY DATA:**
- **COMPANY CONFORMED NAME:** Annexon, Inc.
- **CENTRAL INDEX KEY:** 0001528115
- **STANDARD INDUSTRIAL CLASSIFICATION:** PHARMACEUTICAL PREPARATIONS [2834]
- **ORGANIZATION NAME:** 03 Life Sciences
- **EIN:** 275414423
- **STATE OF INCORPORATION:** DE
- **FISCAL YEAR END:** 1231

**FILING VALUES:**
- **FORM TYPE:** 424B5
- **SEC ACT:** 1933 Act
- **SEC FILE NUMBER:** 333-278246
- **FILM NUMBER:** 251479405

**BUSINESS ADDRESS:**
- **STREET 1:** 1400 SIERRA POINT PARKWAY
- **STREET 2:** BLDG C, SUITE 200
- **CITY:** BRISBANE
- **STATE:** CA
- **ZIP:** 94005
- **BUSINESS PHONE:** (650) 822-5500

**MAIL ADDRESS:**
- **STREET 1:** 1400 SIERRA POINT PARKWAY
- **STREET 2:** BLDG C, SUITE 200
- **CITY:** BRISBANE
- **STATE:** CA
- **ZIP:** 94005

##### [**Table of Contents**](#toc)
**Filed Pursuant to Rule 424(b)(5)<br>Registration No. 333-278246** 

**Prospectus supplement** 

**(To prospectus dated April 1, 2024)**![LOGO](g34136g00r00.jpg)

25,096,153 Shares of Common Stock

Pre-Funded Warrants to Purchase up to 3,750,000 Shares of Common Stock

We are offering 25,096,153 shares of our common stock, par value $0.001 per share, or, in lieu of common stock to certain investors that so choose, pre-funded warrants to purchase up to 3,750,000 shares of our common stock. The purchase price of each pre-funded warrant equals the price per share at which shares of our common stock are being sold to the public in this offering, minus $0.001, and the exercise price of each pre-funded warrant equals $0.001 per share. We are also offering the shares of our common stock that are issuable from time to time upon exercise of the pre-funded warrants.

There is no established public trading market for the pre-funded warrants, and we do not expect a market to develop. We do not intend to apply for listing of the pre-funded warrants on the Nasdaq Global Select Market or any other securities exchange or nationally recognized trading system. Without an active trading market, the liquidity of the pre-funded warrants will be limited.

Our common stock is listed on the Nasdaq Global Select Market under the symbol "ANNX." On November 11, 2025, the last reported sale price of our common stock on the Nasdaq Global Select Market was $2.97 per share.

We are a "smaller reporting company" as defined under the federal securities laws and, as such, have elected to comply with certain reduced public company disclosure and reporting requirements.

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| | | | |
|:---|:---|:---|:---|
|  | Per Share | Per<br>Pre-Funded<br>Warrant | Total |
|  Public offering price | $2.600 | $2.599 | $74996247.80 |
|  Underwriting discounts and commissions(1) | $0.156 | $0.156 | $4499999.87 |
|  Proceeds to Annexon, Inc., before expenses | $2.444 | $2.443 | $70496247.96 |

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(1) See "Underwriting" for a description of the compensation payable to the underwriters.

We have granted the underwriters an option for a period of 30 days to purchase up to an additional 4,326,922 shares of common stock. See "Underwriting" for more information.

**Investing in our common stock involves a high degree of risk. Please read "[Risk factors](#supptx34136_4)" beginning on page S-9 of this prospectus supplement, in the accompanying prospectus and in the documents incorporated by reference into this prospectus supplement and the accompanying prospectus.** 

**Neither the Securities and Exchange Commission nor any state securities commission has approved or disapproved of these securities or determined if this prospectus supplement or the accompanying prospectus is truthful or complete. Any representation to the contrary is a criminal offense.** 

The underwriters expect to deliver the shares of common stock and pre-funded warrants to purchasers on or about November 14, 2025.

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| | | |
|:---|:---|:---|
| **Goldman Sachs & Co. LLC** | **TD Cowen** | **Wells Fargo Securities** |

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The date of this Prospectus Supplement is November 12, 2025

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**TABLE OF CONTENTS** 

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| | |
|:---|:---|
| **Prospectus supplement** | **Prospectus supplement** |
|  [About This Prospectus Supplement](#supptx34136_1) | S-1 |
|  [Prospectus Supplement Summary](#supptx34136_2) | S-3 |
|  [Risk Factors](#supptx34136_4) | S-9 |
|  [Special Note Regarding Forward-Looking Statements](#supptx34136_5) | S-12 |
|  [Use of Proceeds](#supptx34136_6) | S-14 |
|  [Dilution](#supptx34136_7) | S-15 |
|  [Description of Securities We Are Offering](#supptx34136_8) | S-17 |
|  [Material U.S. Federal Income Tax Considerations](#supptx34136_9) | S-19 |
|  [Underwriting](#supptx34136_10) | S-26 |
|  [Legal Matters](#supptx34136_11) | S-35 |
|  [Experts](#supptx34136_12) | S-35 |
|  [Where You Can Find Additional Information](#supptx34136_13) | S-35 |
|  [Incorporation of Certain Information by Reference](#supptx34136_14) | S-36 |
| **Prospectus** | **Prospectus** |
|  [About this Prospectus](#tx34136_1) | 1 |
|  [Prospectus Summary](#tx34136_2) | 3 |
|  [Risk Factors](#tx34136_3) | 9 |
|  [Special Note Regarding Forward-Looking Statements](#tx34136_4) | 10 |
|  [Use of Proceeds](#tx34136_5) | 12 |
|  [Description of Capital Stock](#tx34136_6) | 13 |
|  [Description of Debt Securities](#tx34136_7) | 19 |
|  [Description of Warrants](#tx34136_8) | 26 |
|  [Description of Units](#tx34136_9) | 29 |
|  [Legal Ownership of Securities](#tx34136_10) | 30 |
|  [Plan of Distribution](#tx34136_11) | 34 |
|  [Legal Matters](#tx34136_12) | 37 |
|  [Experts](#tx34136_13) | 37 |
|  [Where You Can Find More Information](#tx34136_14) | 37 |
|  [Incorporation by Reference](#tx34136_15) | 37 |

---

S-i

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**ABOUT THIS PROSPECTUS SUPPLEMENT** 

This prospectus supplement and the accompanying prospectus are part of a registration statement on Form S-3 that we have filed with the Securities and Exchange Commission, or the SEC, under the Securities Act of 1933, as amended, or the Securities Act, utilizing a "shelf" registration process. Under this shelf registration process, we may, from time to time, offer and sell in one or more offerings the type of securities described in the accompanying prospectus.

We provide information to you about this offering of our securities in two separate documents that are bound together: (1) this prospectus supplement, which describes the specific details regarding this offering of common stock and pre-funded warrants, and (2) the accompanying prospectus, which provides general information, some of which may not apply to this offering. Generally, when we refer to this "prospectus supplement," we are referring to both documents combined. If information in this prospectus supplement is inconsistent with the accompanying prospectus, you should rely on this prospectus supplement. However, if any statement in one of these documents is inconsistent with a statement in another document having a later date—for example, a document incorporated by reference in this prospectus supplement—the statement in the document having the later date modifies or supersedes the earlier statement as our business, financial condition, results of operations and prospects may have changed since the earlier dates.

We have not, and the underwriters have not, authorized anyone to provide you with any information other than that contained in or incorporated by reference in this prospectus supplement, the accompanying prospectus or in any free writing prospectus prepared by or on behalf of us or to which we have referred you. We and the underwriters take no responsibility for, and can provide no assurance as to the reliability of, any other information that others may give you. We are not, and the underwriters are not, making an offer to sell or soliciting an offer to buy our securities in any jurisdiction where an offer or solicitation is not authorized or in which the person making that offer or solicitation is not qualified to do so or to anyone to whom it is unlawful to make an offer or solicitation. You should assume that the information appearing in this prospectus supplement, the accompanying prospectus, the documents incorporated by reference herein and therein, and in any free writing prospectus that we may authorize for use in connection with this offering, is accurate only as of the date of those respective documents. Our business, financial condition, results of operations and prospects may have changed since those dates. You should read this prospectus supplement, the accompanying prospectus, the documents incorporated by reference into this prospectus, and any free writing prospectus that we may authorize for use in connection with this offering, in their entirety before making an investment decision. You should also read and consider the information in the documents to which we have referred you in the sections of this prospectus supplement titled "Where you can find more information" and "Incorporation of certain information by reference."

We further note that the representations, warranties and covenants made by us in any agreement that is filed as an exhibit to any document that is incorporated by reference herein were made solely for the benefit of the parties to such agreement, including, in some cases, for the purpose of allocating risk among the parties to such agreement, and should not be deemed to be a representation, warranty or covenant to you. Moreover, such representations, warranties or covenants were accurate only as of the date when made. Accordingly, such representations, warranties and covenants should not be relied on as accurately representing the current state of our affairs.

We and the underwriters are offering to sell, and seeking offers to buy, shares of our common stock and pre-funded warrants only in jurisdictions in which offers and sales are permitted. The distribution of this prospectus supplement and the accompanying prospectus and the offering of the shares of our common stock and pre-funded warrants in certain jurisdictions may be restricted by law. Persons outside the United States who come into possession of this prospectus supplement and the

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accompanying prospectus must inform themselves about, and observe any restrictions relating to, the offering of the shares of our common stock and pre-funded warrants and the distribution of this prospectus supplement and the accompanying prospectus outside the United States. This prospectus supplement and the accompanying prospectus do not constitute, and may not be used in connection with, an offer to sell, or a solicitation of an offer to buy, any securities offered by this prospectus supplement by any person in any jurisdiction in which it is unlawful for such person to make such an offer or solicitation.

When we refer to "Annexon," "ANNX," "we," "our," "us" and the "Company" in this prospectus supplement, we mean Annexon, Inc. and its consolidated subsidiary, unless otherwise specified. When we refer to "you," we mean the potential holders of our securities.

"Annexon," "Annexon, Inc.," the Annexon logo and other trade names, trademarks or service marks of Annexon are the property of Annexon, Inc. This prospectus supplement also contains references to our trademarks and to trademarks belonging to other entities. Trade names, trademarks and service marks of other companies appearing in this prospectus supplement are the property of their respective holders. We do not intend our use or display of other companies' trade names or trademarks to imply a relationship with, or endorsement or sponsorship of us by, any other companies. Solely for convenience, the trade names and trademarks may be referred to without the <sup>®</sup> and <sup>™</sup> symbols, but such references should not be construed as any indicator that their respective owners will not assert their rights thereto.

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**PROSPECTUS SUPPLEMENT SUMMARY** 

*This summary provides a general overview of selected information and does not contain all of the information you should consider before buying our securities. Therefore, you should read the entire prospectus supplement, accompanying prospectus and any free writing prospectus that we have authorized for use in connection with this offering carefully, including the information incorporated by reference herein and therein, before deciding to invest in our securities. Investors should carefully consider the information set forth under the section titled "Risk factors" beginning on page S-9 of this prospectus supplement and in the documents incorporated by reference into this prospectus supplement, including our Annual Report on Form 10-K and our Quarterly Reports on Form 10-Q.* 

**Company Overview** 

We are a biopharmaceutical company advancing a late-stage clinical platform targeting neuroinflammation across life-changing complement-mediated neuroinflammatory diseases. The classical complement pathway is a core component to the body's immune system that activates a powerful inflammatory cascade. We believe that by stopping the classical complement pathway at its start by targeting C1q, the initiating molecule of the classical complement pathway, our approach may have the potential to provide more complete protection against complement-mediated disorders of the body, brain and eye.

Using our proprietary platform, we are identifying and characterizing the role of the classical complement pathway in three therapeutic areas—autoimmune, neurodegeneration and ophthalmology. In so doing, we are advancing a pipeline of product candidates designed to block the early classical cascade and all downstream pathway components and their tissue-damaging functions. Our goal is to suppress excessive or aberrant classical complement activity that contributes to chronic inflammation and tissue damage to slow or even halt disease progression, while preserving the beneficial immune functions of the lectin and alternative complement pathways involved in the clearance of pathogens and damaged cells. We have demonstrated robust target engagement in the body, brain and eye, and clinical proof of concept in multiple diseases, and have focused our resources on development of three priority programs:

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;• **Guillain-Barré Syndrome, or GBS:** We are advancing tanruprubart (formerly ANX005), 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 approximately 150,000 people worldwide. There are currently no therapies
approved by the U.S. Food and Drug Administration, or 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 that includes
successful placebo-controlled proof-of-concept, or POC, and Phase 3 data, Real-World Evidence, or RWE, indirect comparison data of tanruprubart's treatment effect
versus current standard of care, and drug-drug interaction safety data with tanruprubart with current standard of care. Completed placebo-controlled studies were conducted in Southeast Asia given GBS' sudden and debilitating disease course and
lack of approved comparator in the U.S. The open-label FORWARD study in the U.S. and Europe is ongoing and currently designed to broaden Western experience with tanruprubart. We continue to engage with applicable EU and U.S. regulators to advance
tanruprubart towards registration worldwide. Productive regulatory

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interactions with European Rapporteurs and the Pediatric Committee of the European Medicines Agency reaffirmed the current data package is on track for our Marketing Authorization Application, or MAA, submission expected in January 2026. Dialogue with the FDA is ongoing regarding the generalizability package supporting a biologics license application, or BLA, submission. We also anticipate initial pharmacokinetics, or PK, and pharmacodynamics, or PD, biomarker and functional data from the FORWARD study in 2026. Tanruprubart has been granted Fast Track and orphan drug designation for the treatment of GBS from the FDA. Tanruprubart has also been granted orphan designation from the European Medicines Agency, or EMA. <br>

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;• **Geographic Atrophy, or GA:** We are advancing vonaprument (formerly ANX007), an investigational neuroprotective
inhibitor of C1q and the classical complement cascade delivered intravitreally for dry AMD with GA, a leading cause of blindness affecting more than eight million people worldwide. There are no approved therapies for GA targeting the preservation of
vision. Vonaprument is the only investigational therapy in GA to show significant vision preservation on assessments of best corrected visual acuity, or BCVA, and low luminance visual acuity, demonstrating significant protection from vision loss in
both normal and low light conditions, as well as significant preservation of central retinal photoreceptors necessary for visual acuity. In the Phase 2 ARCHER trial, vonaprument also reduced risk of 15-letter vision loss by more than 70%. In July 2025, we completed enrollment of 659 patients in ARCHER II, a global, sham-controlled, double-masked Phase 3 trial. The primary endpoint of ARCHER II is prevention of ≥ 15-letter loss of BCVA, and a secondary objective structural measure is prevention of ellipsoid zone, or EZ, loss. 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 who have dry AMD with GA, assuming positive Phase 3 results.
We plan to report topline data in the second half of 2026. 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 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.

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;• **ANX1502 for Autoimmune Indications:** We are advancing ANX1502, 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, or SAD, and multiple-ascending dose, or MAD, 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.

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**Corporate Information** 

We were incorporated under the laws of the State of Delaware on March 3, 2011. Our principal executive offices are located at 1400 Sierra Point Parkway, Bldg C, Suite 200, Brisbane, California 94005, and our telephone number is (650) 822-5500. Our corporate website address is www.annexonbio.com. Information contained on, or accessible through, our website shall not be deemed incorporated into and is not a part of this prospectus supplement or the registration statement of which it forms a part. We have included our website in this prospectus supplement solely as an inactive textual reference.

**Implications of Being a Smaller Reporting Company** 

We are a "smaller reporting company" as defined in Item 10(f)(1) of Regulation S-K. Smaller reporting companies may take advantage of certain reduced disclosure obligations, including, among other things, providing only two years of audited financial statements and reduced disclosure obligations regarding executive compensation. We will be a smaller reporting company and may continue to take advantage of the scaled-back disclosures available to smaller reporting companies for so long as (i) the market value of our common stock held by non-affiliates is less than $250.0 million measured on the last business day of our most recently completed second fiscal quarter or (ii) at the time of determination at the end of the fiscal year, (a) our annual revenue is less than $100.0 million during the most recently completed fiscal year for which audited financial statements are then-available and (b) the market value of our common stock held by non-affiliates is less than $700.0 million measured on the last business day of our most recently completed second fiscal quarter.

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**THE OFFERING** 

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| | |
|:---|:---|
|  Common stock offered by us | 25,096,153 shares of our common stock. |
|  Pre-funded warrants offered by us | We are also offering, in lieu of common stock to certain investors that so choose, pre-funded warrants to purchase up to 3,750,000 shares of our common stock. The purchase price of each pre-funded warrant equals the price per share at which the shares of our common stock are being sold to the public in this offering, minus $0.001 which is the exercise price of each pre-funded warrant per share. The pre-funded warrants do not expire and each pre-funded warrant will be exercisable at any time after the date of issuance of such pre-funded warrant, subject to an ownership limitation. See "Description of Securities We Are Offering—Pre-Funded Warrants" on page S-17 of this prospectus supplement. This prospectus supplement also relates to the offering of the shares of our common stock issuable upon exercise of the pre-funded warrants. |
|  | The lock-up restrictions described under the section "Underwriting" will not apply to issuance of common stock upon the exercise of the pre-funded warrants during the 60-day period following the date of this prospectus supplement to be filed in connection with this offering. |
|  Options to purchase additional shares | We have granted the underwriters an option to purchase up to an additional 4,326,922 shares of our common stock from us. This option is exercisable, in whole or in part, for a period of 30 days following the date of this prospectus supplement. |
|  Common stock to be outstanding immediately after this offering | <br>140,218,735 shares (or 144,545,657 shares if the underwriters exercise their option to purchase additional shares of common stock in full) in each case assuming no exercise of any pre-funded warrants issued in this offering. |
|  Use of proceeds | We estimate that the net proceeds to us from this offering will be approximately $69.9 million, or approximately $80.4 million if the underwriters' option to purchase additional shares of our common stock is exercised in full, in each case, after deducting the estimated underwriting discounts and commissions and estimated offering expenses payable by us. |

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|:---|:---|
|  | We currently intend to use the net proceeds from this offering, together with our existing cash and cash equivalents and short-term investments, to advance our late-stage neuroinflammation platform led by global registrational programs, tanruprubart in GBS and vonaprument in dry AMD with GA and for working capital and other general corporate purposes. See "Use of proceeds" on page S-14 of this prospectus supplement. |
|  Risk factors | Investing in our common stock involves significant risks. You should read the "Risk factors" section of this prospectus supplement and in the documents incorporated by reference in this prospectus supplement and the accompanying prospectus for a discussion of factors to consider before deciding to purchase shares of our common stock. |
|  Nasdaq Global Select Market symbol | "ANNX."<br>We do not intend to apply for listing of the pre-funded warrants on the Nasdaq Global Select Market or any other securities exchange or nationally recognized trading system. There is no public trading market for the pre-funded warrants, and we do not expect a market to develop. Without a trading market, the liquidity of the pre-funded warrants will be extremely limited. See "Description of securities we are offering—Pre-funded warrants" for additional information. |

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The number of shares of common stock to be outstanding immediately after this offering is based on 115,122,582 shares of common stock outstanding as of September 30, 2025, and excludes:

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;• 19,381,754 shares of common stock issuable upon the exercise of stock options outstanding as of September 30, 2025,
with a weighted-average exercise price of $6.64 per share;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;• 128,000 shares of common stock issuable upon the exercise of stock options granted subsequent to September 30, 2025,
with a weighted average exercise price of $3.10 per share;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;• 1,308,942 shares of common stock issuable in connection with the vesting and settlement of restricted stock units
outstanding as of September 30, 2025;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;• 38,543,577 shares of common stock issuable upon the exercise of pre-funded warrants
outstanding as of September 30, 2025, with a weighted average exercise price of $0.001 per share;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;• 6,877,622 shares of common stock issuable upon the exercise of common warrants outstanding as of September 30, 2025,
with a weighted average exercise price of $5.81 per share;

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&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;• 1,053,719 shares of common stock reserved for future issuance under our 2020 Incentive Award Plan, as of September 30,
2025, as well as any automatic increases in the number of shares of our common stock reserved for future issuance under this plan;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;• 3,077,259 shares of common stock available for future grant under our 2022 Employment Inducement Award Plan as of
September 30, 2025;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;• 2,959,996 shares of common stock reserved for future issuance under our Employee Stock Purchase Plan as of
September 30, 2025, as well as any automatic increases in the number of shares of our common stock reserved for future issuance under this plan; and

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;• 4,504,865 shares of our common stock issued subsequent to September 30, 2025 pursuant to the 2024 ATM Program (as
defined below).

On March 26, 2024, we entered into a sales agreement with Cowen and Company, LLC, or TD Cowen, as sales agent, pursuant to which we may issue and sell shares of our common stock through TD Cowen for an aggregate maximum offering price of $100.0 million from time to time under an at-the-market offering program, or 2024 ATM Program, in such amounts as we may determine, subject to certain limitations contained therein and under applicable securities laws. As of the date of this prospectus supplement, we have sold 10,490,824 shares of our common stock under the 2024 ATM Program. We have agreed not to make any sales under the 2024 ATM Program until the expiration or waiver of the 60-day lock-up period applicable to us and described in the section titled "Underwriting."

Unless otherwise indicated, all information in this prospectus supplement assumes no exercise by the underwriters of their option to purchase additional shares of our common stock and no exercise or settlement, as applicable, of the outstanding options, restricted stock units, pre-funded warrants and common warrants described above and no exercise of pre-funded warrants offered and sold in this offering.

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**RISK FACTORS** 

*Our business involves significant risks, some of which are described below. You should carefully review the risks and uncertainties described below and under the section titled "Risk factors" contained in our Annual Report on Form 10-K for the year ended December 31, 2024, as updated by our subsequent Quarterly Reports on Form 10-Q and other filings under the Securities Exchange Act of 1934, as amended, or Exchange Act, each of which is incorporated by reference in this prospectus supplement in their entirety, together with other information in this prospectus supplement and the accompanying prospectus, and the information and documents incorporated by reference in this prospectus supplement and the accompanying prospectus, and any free writing prospectus that we have authorized for use in connection with this offering before you make a decision to invest in our securities. If any of the following risks actually occur, it could harm our business, operating results, financial condition and future prospects. In such event, the market price of our common stock or value of the pre-funded warrants could decline and you could lose all or part of your investment. Additional risks and uncertainties not presently known to us or that we currently deem immaterial may also impair our business operations.* 

**Risks Relating to This Offering** 

***Our management team may invest or spend the proceeds of this offering in ways with which you may not agree or in ways which may not yield a significant return.***

Our management will have broad discretion over the use of proceeds from this offering. We currently intend to use the net proceeds from this offering, together with our existing cash and cash equivalents and short-term investments, to advance our late-stage neuroinflammation platform led by global registrational programs, tanruprubart in GBS and vonaprument in dry AMD with GA and for working capital and other general corporate purposes. Our management will have considerable discretion in the application of the net proceeds, and you will not have the opportunity, as part of your investment decision, to assess whether the proceeds are being used appropriately. Because of the number and variability of factors that will determine our use of the net proceeds from this offering, their ultimate use may vary substantially from their currently intended use. The net proceeds may be used for corporate purposes that do not increase our operating results or enhance the value of our common stock. Our failure to apply these funds effectively could have a material adverse effect on our business, financial condition and results of operations, delay the development of our product candidates and cause the price of our common stock to decline.

***The pre-funded warrants are not listed on any exchange, and we do not intend to list the pre-funded warrants on any exchange. There is no public market for the pre-funded warrants being offered in this offering.***

There is no established public trading market for the pre-funded warrants being offered in this offering, and we do not expect a market to develop. In addition, we do not intend to apply to list these pre-funded warrants on any securities exchange or nationally recognized trading system, including the Nasdaq Global Select Market. Without an active market, the liquidity of these pre-funded warrants will be limited. See "Description of securities we are offering—Pre-funded warrants."

***We will not receive any meaningful amount of additional funds upon the exercise of the pre-funded warrants.***

Each pre-funded warrant has an exercise price of $0.001 per share of common stock. Each pre-funded warrant will be exercisable until it is fully exercised by means of payment of this nominal purchase price. Accordingly, we will not receive any meaningful additional funds upon the exercise of the pre-funded warrants.

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***Holders of pre-funded warrants purchased in this offering will have no rights as common stockholders until such holders exercise their pre-funded warrants and acquire our common stock.***

Until holders of the pre-funded warrants acquire shares of our common stock upon exercise of such pre-funded warrants, the holders will have no rights with respect to the shares of our common stock underlying such pre-funded warrants, such as voting rights or the rights to receive dividends. Upon exercise of the pre-funded warrants, the holders will be entitled to exercise the rights of a common stockholder only as to matters for which the record date occurs after the exercise.

***Significant holders or beneficial owners of our common stock may not be permitted to exercise pre-funded warrants that they hold.***

Holders of the pre-funded warrants will not be entitled to exercise any portion of any pre-funded warrant which, upon giving effect to such exercise, would cause the aggregate number of shares of our common stock beneficially owned by the holder (together with its affiliates) to exceed a specified percentage of the number of shares of our common stock outstanding immediately after giving effect to the exercise, as such percentage ownership is determined in accordance with the terms of the pre-funded warrants. See "Description of securities we are offering—Pre-funded warrants." As a result, you may not be able to exercise your pre-funded warrants for shares of our common stock at a time when it would be financially beneficial for you to do so. In such circumstance you could seek to sell your pre-funded warrants to realize value, but you may be unable to do so in the absence of an established trading market for the pre-funded warrants.

***If you purchase shares of our common stock in this offering, you will experience immediate and substantial dilution in the book value of your shares.***

The offering price per share of our common stock and per pre-funded warrant in this offering each exceeds the net tangible book value per share of our common stock outstanding prior to this offering. As a result, if you purchase shares of our common stock in this offering, you will experience immediate dilution of $0.99 per share, based on the public offering price of $2.60 per share of common stock and our net tangible book value per share as of September 30, 2025. The exercise or vesting and settlement, as applicable, of outstanding stock options, restricted stock units or warrants may result in further dilution of your investment. See the section titled "Dilution" below for a more detailed illustration of the dilution you may incur if you participate in this offering.

***If we do not maintain a current and effective registration statement relating to the shares of common stock issuable upon exercise of the pre-funded warrants, holders will only be able to exercise such pre-funded warrants on a "cashless basis."***

If we do not maintain a current and effective registration statement relating to the shares of common stock issuable upon exercise of the pre-funded warrants at the time that holders wish to exercise such pre-funded warrants, they will only be able to exercise them on a "cashless basis" provided that an exemption from registration is available. As a result, the number of shares of common stock that holders will receive upon exercise of the pre-funded warrants will be fewer than it would have been had such holder exercised his warrant for cash, and holders may be limited in their ability to immediately sell shares upon exercise subject to volume or other securities law limitations. Further, if an exemption from registration is not available, holders would not be able to exercise on a cashless basis and would only be able to exercise their pre-funded warrants for cash if a current and effective registration statement relating to the shares of common stock issuable upon exercise of the pre-funded warrants is available.

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***You may experience future dilution as a result of future equity offerings and the perception that any such offerings could occur may depress our stock price and our ability to raise funds in any new stock offering.***

In order to raise additional capital, we expect to in the future offer additional shares of our common stock or other securities convertible into or exchangeable for our common stock. The price per share at which we sell additional shares of our common stock or other securities convertible into or exchangeable for our common stock in future transactions may be higher or lower than the price per share paid by investors in this offering. Our stockholders would experience immediate dilution upon the sale of any shares of our common stock or other securities convertible into or exchangeable for our common stock at a discount from the current trading price of our common stock. In addition, the perception that such sales could occur may lower the market price of our common stock and may make it more difficult for us to sell our common stock or other securities convertible into or exchangeable for our common stock in the future at a time and price that our management deems acceptable, or at all.

***We do not currently intend to pay dividends on our common stock, and any return to investors is expected to come, if at all, only from potential increases in the price of our common stock.***

We have never declared or paid any cash dividends on our capital stock, and you should not rely on an investment in our common stock to provide dividend income. We currently intend to retain all of our future earnings, if any, to finance the growth and development of our business and do not anticipate declaring or paying any cash dividends for the foreseeable future. As a result, capital appreciation, if any, of our common stock will be your sole source of gain for the foreseeable future.

***An active trading market for our common stock may not be sustained following this offering.***

Although our common stock is listed on the Nasdaq Global Select Market, an active trading market for our shares may not be sustained. If an active market for our common stock does not continue, it may be difficult for you to sell your shares, including shares you may purchase in this offering, without depressing the market price for the shares or sell your shares at all. Any inactive trading market for our common stock may also impair our ability to raise capital to continue to fund our operations by selling shares and may impair our ability to acquire other companies or technologies by using our shares as consideration.

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**SPECIAL NOTE REGARDING FORWARD-LOOKING STATEMENTS** 

This prospectus supplement, the accompany prospectus, including the documents incorporated by reference herein and therein, and any free writing prospectus that we have authorized for use in connection with this offering contain forward-looking statements within the meaning of Section 27A of the Securities Act and Section 21E of the Exchange Act, based upon current expectations that involve risks and uncertainties. In some cases, you can identify forward-looking statements by terminology such as "anticipate," "believe," "continue," "could," "estimate," "expect," "intend," "may," "plan," "potentially," "predict," "should," "will" or the negative of these terms or other similar expressions. These forward-looking statements include, but are not limited to, statements about:

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;• our expectations regarding the potential market size and size of the potential patient populations for our product
candidates and any future product candidates, if approved for commercial use;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;• our clinical and regulatory development plans;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;• our expectations with regard to the initiation, scope, rate of progress, enrollment, dosing and results of our clinical
studies, preclinical studies and research and development programs, including the timing and availability of data from such studies;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;• the timing of commencement of future nonclinical studies, preclinical studies and clinical trials and research and
development programs;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;• our ability to acquire, discover, develop and advance product candidates into, and successfully complete, clinical trials;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;• our intentions and our ability to establish collaborations and/or partnerships;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;• the timing or likelihood of regulatory filings and approvals for our product candidates;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;• our commercialization, marketing and manufacturing capabilities and expectations;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;• our intentions with respect to the commercialization of our product candidates;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;• the pricing and reimbursement of our product candidates, if approved;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;• the implementation of our business model and strategic plans for our business and product candidates, including additional
indications for which we may pursue;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;• the scope of protection we are able to establish and maintain for intellectual property rights covering our product
candidates, including the projected terms of patent protection;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;• estimates regarding the sufficiency of our cash resources and our expenses, future revenue, capital requirements, our needs
for additional financing and our ability to obtain additional capital;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;• the potential future sales of our common stock under our at-the-market offering program;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;• our intended use of proceeds from this offering, including sufficiency of such proceeds to advance our late-stage
neuroinflammation platform led by global registrational programs, tanruprubart in GBS and vonaprument in dry AMD with GA and for working capital and other general corporate purposes and our existing cash and cash equivalents and short-term
investments;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;• the potential future sales of our common stock;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;• our anticipated cash runway;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;• our future financial or operating performance;

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&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;• developments and projections relating to our competitors and our industry, including competing products; and

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;• our plans, objectives, expectations and initiations and any other statements that are not historical facts.

These forward-looking statements are based on management's current expectations, estimates, forecasts and projections about our business and the industry in which we operate and management's beliefs and assumptions and are not guarantees of future performance or development and involve known and unknown risks, uncertainties and other factors that are in some cases beyond our control. As a result, any or all of our forward-looking statements in this prospectus supplement may turn out to be inaccurate and you should not rely upon forward-looking statements as predictions of future events. Factors that may cause actual results to differ materially from current expectations include, among other things, those listed under the section titled "Risk factors" in this prospectus supplement, the accompanying prospectus, and the documents incorporated by reference herein and therein. Moreover, we operate in a very competitive and rapidly changing environment. New risks emerge from time to time and it is not possible for our management to predict all risks, nor can we assess the impact of all factors on our business or the extent to which any factor, or combination of factors, may cause actual results to differ materially from those contained in any forward-looking statements we may make. Potential investors are urged to consider these factors carefully in evaluating the forward-looking statements. These forward-looking statements speak only as of the date of this prospectus supplement. Except as required by law, we assume no obligation to update or revise these forward-looking statements for any reason, even if new information becomes available in the future. You should, however, review the factors and risks we describe in the reports we will file from time to time with the SEC after the date of this prospectus supplement. See "Where you can find more information" and "Incorporation of certain information by reference."

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**USE OF PROCEEDS** 

We estimate that the net proceeds to us from this offering will be approximately $69.9 million, or approximately $80.4 million if the underwriters exercise their option to purchase additional shares of our common stock in full, in each case, after deducting the estimated underwriting discounts and commissions and estimated offering expenses payable by us. These estimates exclude the proceeds, if any, from the exercise of pre-funded warrants sold in this offering.

We currently intend to use the net proceeds from this offering, together with our existing cash and cash equivalents and short-term investments, to advance our late-stage neuroinflammation platform led by global registrational programs, tanruprubart in GBS and vonaprument in dry AMD with GA and for working capital and other general corporate purposes.

The amounts and timing of our actual expenditures will depend on numerous factors, including our development and commercialization efforts with respect to our product candidates, as well as the amount of cash used in our operations. We therefore cannot estimate with certainty the amount of net proceeds to be used for the purposes described above. Based upon our current operating plan, we believe that the net proceeds of our offering, together with our existing cash and cash equivalents and short-term investments, will extend operations one year past the anticipated vonaprument topline pivotal data in GA. We have based this estimate on assumptions that may prove to be incorrect, and we could use our available capital resources sooner than we currently expect.

Pending the uses described above, we plan to invest the net proceeds from this offering in short-term, investment-grade, interest-bearing securities, certificates of deposit or direct or guaranteed obligations of the U.S. government. We cannot predict whether the proceeds invested will yield a favorable return. Our management will have broad discretion in the use of the net proceeds from this offering, and investors will be relying on the judgment of our management regarding the application of the net proceeds.

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**DILUTION** 

If you invest in our common stock or pre-funded warrants in this offering, your interest will be diluted to the extent of the difference between the price per share or pre-funded warrant that you pay and the as adjusted net tangible book value per share of our common stock immediately after this offering.

As of September 30, 2025, our net tangible book value was $161.4 million, or $1.40 per share of common stock. We calculate net tangible book value per share by dividing the net tangible book value, which is tangible assets less total liabilities, by the number of outstanding shares of our common stock at September 30, 2025. Dilution with respect to net tangible book value per share represents the difference between the amount per share paid by purchasers of shares of common stock in this offering and the net tangible book value per share of our common stock immediately after this offering.

After giving effect to the sale of shares of common stock and pre-funded warrants in this offering, at a public offering price of $2.60 per share or $2.599 per pre-funded warrant, and after deducting the estimated underwriting discounts and commissions and estimated offering expenses payable by us, our as adjusted net tangible book value as of September 30, 2025 would have been approximately $231.3 million, or approximately $1.61 per share. This represents an immediate increase in net tangible book value of $0.21 per share to our existing stockholders and an immediate dilution of $0.99 per share to investors participating in this offering.

The following table illustrates this dilution on a per share basis:

---

| | | |
|:---|:---|:---|
|  Public offering price per share |  | $2.6 |
| &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; Net tangible book value per share as of September 30, 2025 | $1.4 |  |
| &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; Increase in net tangible book value per share attributable to investors purchasing our common stock and pre-funded warrants in this offering | $0.21 |  |
|  As adjusted net tangible book value per share after giving effect to this offering |  | $1.61 |
|  Dilution per share to investors purchasing our common stock in this offering |  | $0.99 |

---

If the underwriters exercise their option to purchase additional shares of our common stock in full in this offering, the increase in the as adjusted net tangible book value per share to existing stockholders would be $0.23 per share and the dilution to investors purchasing common stock in this offering would be $0.97 per share.

Except as noted otherwise, the above discussion and table are based on an aggregate of 115,122,582 shares of common stock outstanding as of September 30, 2025, but excludes:

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;• 19,381,754 shares of common stock issuable upon the exercise of stock options outstanding as of September 30, 2025,
with a weighted-average exercise price of $6.64 per share;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;• 128,000 shares of common stock issuable upon the exercise of stock options granted subsequent to September 30, 2025,
with a weighted average exercise price of $3.10 per share;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;• 1,308,942 shares of common stock issuable in connection with the vesting and settlement of restricted stock units
outstanding as of September 30, 2025;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;• 38,543,577 shares of common stock issuable upon the exercise of pre-funded warrants
outstanding as of September 30, 2025, with a weighted average exercise price of $0.001 per share;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;• 6,877,622 shares of common stock issuable upon the exercise of common warrants outstanding as of September 30, 2025,
with a weighted average exercise price of $5.81 per share;

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&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;• 1,053,719 shares of common stock reserved for future issuance under our 2020 Incentive Award Plan, as of September 30,
2025;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;• 3,077,259 shares of common stock available for future grant under our 2022 Employment Inducement Award Plan as of
September 30, 2025;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;• 2,959,996 shares of common stock reserved for future issuance under our Employee Stock Purchase Plan as of
September 30, 2025; and

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;• 4,504,865 shares of our common stock issued subsequent to September 30, 2025 pursuant to the 2024 ATM Program.

On March 26, 2024, we entered into a sales agreement with TD Cowen, as sales agent, pursuant to which we may issue and sell shares of our common stock through TD Cowen for an aggregate maximum offering price of $100.0 million from time to time under the 2024 ATM Program in such amounts as we may determine, subject to certain limitations contained therein and under applicable securities laws. As of the date of this prospectus supplement, we have sold 10,490,824 shares of our common stock under the 2024 ATM Program. We have agreed not to make any sales under the 2024 ATM Program until the expiration or waiver of the 60-day lock-up period applicable to us and described in the section titled "Underwriting."

New investors will experience further dilution if any of our outstanding options, restricted stock units or warrants are exercised or vest and settle, as applicable, or new options or restricted stock units are issued and exercised or vest and settle, as applicable, under our equity incentive plans. In addition, we may choose to raise additional capital due to market conditions or strategic considerations even if we believe that we have sufficient funds for our current or future operating plans. To the extent that additional capital is raised through the sale of equity or convertible debt securities, the issuance of these securities could result in further dilution to our stockholders.

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**DESCRIPTION OF SECURITIES WE ARE OFFERING** 

**Common Stock** 

We are offering shares of our common stock in this offering. See "Description of capital stock" in the accompanying prospectus for more information regarding our shares of common stock.

**Pre-funded Warrants** 

The following is a summary of the material attributes and characteristics of the pre-funded warrants. The form of pre-funded warrants will be provided to the pre-funded warrant purchasers in this offering and will be filed as an exhibit to a Current Report on Form 8-K in connection with this offering and incorporated by reference into the registration statement of which this prospectus supplement forms a part. The following summary is subject in all respects to the provisions contained in the pre-funded warrants. Pre-funded warrants will be issued in certificated form only.

***Duration and Exercise Price***

Each pre-funded warrant entitles the holder thereof to purchase shares of our common stock at an exercise price equal to $0.001 per share. Each pre-funded warrant will be exercisable at any time beginning on the date of issuance. The number of shares of our common stock issuable upon exercise of each pre-funded warrant is subject to appropriate adjustment in the event of certain stock dividends, stock splits, reorganizations or similar events affecting our common stock and the exercise price. The pre-funded warrants do not expire.

***Exercisability***

The holder of the pre-funded warrant may exercise the pre-funded warrant by delivering an exercise notice, completed and duly signed, and payment in cash of the exercise price for the number of shares of our common stock for which the pre-funded warrant is being exercised. The holder of the pre-funded warrant may also satisfy its obligation to pay the exercise price through a "cashless exercise," in which the holder receives the net value of the pre-funded warrant in shares of common stock determined according to the formula set forth in the pre-funded warrant. Upon a holder's exercise of the pre-funded warrant, we will issue the shares of common stock to which the holder is entitled pursuant to such exercise within two trading days after the exercise date. A holder of the pre-funded warrant will not be entitled to exercise any portion of such pre-funded warrant that, upon giving effect to such exercise, would cause the aggregate number of shares of our common stock beneficially owned by such holder (together with its affiliates and any other persons whose beneficial ownership of common stock would be aggregated with the holder for purposes of Section 13(d) of the Exchange Act) to exceed 9.99% of the total number of then issued and outstanding shares of common stock, as such percentage ownership is determined in accordance with the terms of the pre-funded warrant and subject to such holder's rights under the pre-funded warrant to increase or decrease such percentage to any other percentage not in excess of 19.99% upon at least 61 days' prior notice from such holder to us.

***Fundamental transaction***

In the event of any fundamental transaction, as described in the pre-funded warrants and generally including any merger with or into another entity, sale of all or substantially all of our assets, tender offer or exchange offer, or reclassification of our shares of common stock, then upon any subsequent exercise of a pre-funded warrant, the holder will have the right to receive as alternative consideration, for each share of common stock that would have been issuable upon such exercise immediately prior to the occurrence of such fundamental transaction, the number of shares of common

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stock of the successor or acquiring corporation of our company, if it is the surviving corporation, and any additional consideration receivable upon or as a result of such transaction by a holder of the number of shares of common stock for which the warrant is exercisable immediately prior to such event.

***Transferability***

Subject to applicable laws, a pre-funded warrant may be transferred at the option of the holder upon surrender of the pre-funded warrant to us together with the appropriate instruments of transfer and payment of funds sufficient to pay any transfer taxes (if applicable).

***Exchange Listing***

There is no trading market available for the pre-funded warrants on any securities exchange or nationally recognized trading system. We do not intend to list the pre-funded warrants on the Nasdaq Global Select Market or any securities exchange or nationally recognized trading system. We will initially serve as the warrant agent under the pre-funded warrants.

***Right as a Stockholder***

Except as otherwise provided in the pre-funded warrants or by virtue of such holder's ownership of shares of our common stock, the holders of the pre-funded warrants do not have the rights or privileges of holders of our common stock, including any voting rights, until they exercise their pre-funded warrants.

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**MATERIAL U.S. FEDERAL INCOME TAX CONSIDERATIONS** 

The following discussion is a summary of the material U.S. federal income tax consequences of the purchase, ownership and disposition of the shares of common stock and pre-funded warrants, which we refer to collectively as the "Securities," issued pursuant to this offering, but does not purport to be a complete analysis of all potential tax effects. The effects of other U.S. federal tax laws, such as estate and gift tax laws, and any applicable state, local or non-U.S. tax laws are not discussed. This discussion is based on the Internal Revenue Code of 1986, as amended, or the Code, Treasury Regulations promulgated thereunder, judicial decisions, and published rulings and administrative pronouncements of the U.S. Internal Revenue Service, or the IRS, in effect as of the date of this offering. These authorities may change or be subject to differing interpretations. Any such change or differing interpretation may be applied retroactively in a manner that could adversely affect a holder of the Securities. We have not sought and will not seek any rulings from the IRS regarding the matters discussed below. There can be no assurance the IRS or a court will not take a contrary position regarding the tax consequences of the purchase, ownership and disposition of the Securities.

This discussion is limited to holders that hold the Securities as a "capital asset" within the meaning of Section 1221 of the Code (generally, property held for investment). This discussion does not address all U.S. federal income tax consequences relevant to a holder's particular circumstances, including the impact of any alternative minimum tax provisions of the Code, the unearned income Medicare contribution tax or the special tax accounting rules under Section 451(b) of the Code. In addition, it does not address consequences relevant to holders subject to particular rules, including, without limitation:

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;• U.S. expatriates and certain former citizens or long-term residents of the United States;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;• persons holding the Securities as part of a hedge, straddle or other risk reduction strategy or as part of a conversion
transaction or other integrated investment;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;• banks, insurance companies and other financial institutions;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;• brokers, dealers or traders in securities;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;• "controlled foreign corporations," "passive foreign investment companies" and corporations that
accumulate earnings to avoid U.S. federal income tax;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;• partnerships or other entities or arrangements treated as partnerships for U.S. federal income tax purposes (and investors
therein);

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;• tax-exempt organizations or governmental organizations;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;• persons deemed to sell the Securities under the constructive sale provisions of the Code;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;• persons holding the Securities as "qualified small business stock" within the meaning of Section 1202 of
the Code, or "Section 1244 stock" under Section 1244 of the Code;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;• persons who hold or receive the Securities pursuant to the exercise of any employee stock option or otherwise as
compensation;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;• persons who acquired the Securities in a transaction subject to the gain rollover provisions of the Code (including
Section 1045 of the Code);

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;• persons that own, or have owned, actually or constructively, more than 5% of our common stock and/or our pre-funded warrants;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;• "qualified foreign pension funds" as defined in Section 897(l)(2) of the Code and entities all of the
interests of which are held by qualified foreign pension funds; and

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;• tax-qualified retirement plans.

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If a partnership (or other entity treated as a partnership for U.S. federal income tax purposes) holds the Securities, the tax treatment of a partner in the partnership will depend on the status of the partner, the activities of the partnership and certain determinations made at the partner level. Accordingly, partnerships holding the Securities and the partners in such partnerships should consult their tax advisors regarding the U.S. federal income tax consequences to them.

**THIS DISCUSSION IS FOR INFORMATION PURPOSES ONLY AND IS NOT INTENDED AS LEGAL OR TAX ADVICE. INVESTORS SHOULD CONSULT THEIR TAX ADVISORS WITH RESPECT TO THE APPLICATION OF THE U.S. FEDERAL INCOME TAX LAWS TO THEIR PARTICULAR SITUATIONS AS WELL AS ANY TAX CONSEQUENCES OF THE PURCHASE, OWNERSHIP AND DISPOSITION OF THE SECURITIES ARISING UNDER THE U.S. FEDERAL ESTATE OR GIFT TAX LAWS OR UNDER THE LAWS OF ANY STATE, LOCAL OR NON-U.S. TAXING JURISDICTION OR UNDER ANY APPLICABLE INCOME TAX TREATY.** 

**Treatment of Pre-funded Warrants** 

Although the characterization of the pre-funded warrants for U.S. federal income tax purposes is not entirely clear, because the exercise price of the pre-funded warrants is a nominal amount, we expect to treat the pre-funded warrants as stock for U.S. federal income tax purposes. Accordingly, a pre-funded warrant should be treated as a share of our common stock for U.S. federal income tax purposes, and a holder of pre-funded warrants should generally be taxed in the same manner as a holder of common stock, as described below. No gain or loss should be recognized upon the exercise of a pre-funded warrant (other than with respect to cash paid in lieu of a fractional share) and, upon exercise, the holding period of a pre-funded warrant should carry over to the share received. Similarly, the tax basis of the pre-funded warrant should carry over to the share received upon exercise, increased by the exercise price. In certain circumstances, the pre-funded warrants may be exercised on a cashless basis. The U.S. federal income tax treatment of an exercise of a warrant on a cashless basis is not clear, and could differ from the consequences described above. It is possible that a cashless exercise could be a taxable event. Holders are urged to consult their tax advisors as to the consequences of an exercise of a pre-funded warrant on a cashless basis, including with respect to their holding period and tax basis in the shares of common stock received upon exercise.

Except where specifically noted below, the following discussion assumes the characterization described above is respected for U.S. federal income tax purposes. However, this characterization is not binding on the IRS, and the IRS may treat the pre-funded warrants as warrants to acquire shares of our common stock. If so, the tax consequences with respect to an investment in our pre-funded warrants could differ. Holders should consult their tax advisors regarding the risks associated with the acquisition of pre-funded warrants pursuant to this offering (including alternative characterizations).

**Tax Considerations Applicable to U.S. Holders** 

***Definition of a U.S. Holder***

For purposes of this discussion, a "U.S. holder" is any beneficial owner of the Securities that, for U.S. federal income tax purposes, is or is treated as any of the following:

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;• an individual who is a citizen or resident of the United States;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;• a corporation created or organized under the laws of the United States, any state thereof or the District of Columbia;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;• an estate, the income of which is subject to U.S. federal income tax regardless of its source; or

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&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;• a trust that (1) is subject to the primary supervision of a U.S. court and the control of one or more United States
persons (within the meaning of Section 7701(a)(30) of the Code), or (2) has made a valid election under applicable Treasury Regulations to be treated as a United States person.

***Distributions***

We do not anticipate declaring or paying in the foreseeable future any cash dividends on our common stock. However, if we do make distributions on the Securities, such distributions of cash or property on the Securities will constitute dividends to the extent paid out of our current or accumulated earnings and profits, as determined for U.S. federal income tax purposes. Dividends received by a corporate U.S. holder may be eligible for a dividends received deduction, subject to applicable limitations. Dividends received by certain non-corporate U.S. holders, including individuals, are generally taxed at the lower applicable long-term capital gains rate provided certain holding period and other requirements are satisfied. Distributions in excess of our current and accumulated earnings and profits will constitute a return of capital and first be applied against and reduce a U.S. holder's adjusted tax basis in its Securities, but not below zero. Any excess will be treated as capital gain and will be treated as described below in the section relating to the sale or disposition of the Securities.

***Sale or Other Taxable Disposition of the Securities***

Upon the sale, exchange or other taxable disposition of the Securities, a U.S. holder generally will recognize capital gain or loss equal to the difference between (i) the amount of cash and the fair market value of any property received upon the sale, exchange or other taxable disposition and (ii) such U.S. holder's adjusted tax basis in the Securities. Such capital gain or loss will be long-term capital gain or loss if the U.S. holder's holding period in such Securities is more than one year at the time of the sale, exchange or other taxable disposition. Long-term capital gains recognized by certain non-corporate U.S. holders, including individuals, generally will be subject to reduced rates of U.S. federal income tax. The deductibility of capital losses is subject to certain limitations.

***Constructive Dividends on Pre-funded Warrants***

A holder of a pre-funded warrant may, in some circumstances, be deemed to have received a distribution subject to U.S. federal income tax as a result of an adjustment or the non-occurrence of an adjustment to the exercise price or to the number of shares of common stock issuable upon exercise of the pre-funded warrant. U.S. holders should consult their tax advisors regarding the proper treatment of any adjustments (or the non-occurrence of any adjustments) to the pre-funded warrants.

***Information Reporting and Backup Withholding***

A U.S. holder may be subject to information reporting and backup withholding on distributions (including deemed distributions) on the Securities, and gross proceeds on the sale or other disposition of the Securities. Certain U.S. holders are exempt from backup withholding, including certain corporations and certain tax-exempt organizations. A U.S. holder will be subject to backup withholding if such holder is not otherwise exempt and such holder:

(a) fails to furnish the holder's taxpayer identification number, which for an individual is ordinarily his or her
social security number;

(b) furnishes an incorrect taxpayer identification number;

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(c) is notified by the IRS that the holder previously failed to properly report payments of interest or dividends; or fails
to certify under penalties of perjury that the holder has furnished a correct taxpayer identification number and that the IRS has not notified the holder that the holder is subject to backup withholding.

Backup withholding is not an additional tax. Any amounts withheld under the backup withholding rules may be allowed as a refund or a credit against a U.S. holder's U.S. federal income tax liability, provided the required information is timely furnished to the IRS. U.S. holders should consult their tax advisors regarding their qualification for an exemption from backup withholding and the procedures for obtaining such an exemption. If backup withholding is applied to you, you should consult with your own tax advisor to determine whether you have overpaid your U.S. federal income tax, and whether you are able to obtain a tax refund or credit of the overpaid amount.

**Tax Considerations Applicable to Non-U.S. Holders** 

For purposes of this discussion, a "non-U.S. holder" is a beneficial owner of the Securities that is neither a U.S. holder nor an entity treated as a partnership for U.S. federal income tax purposes.

***Distributions***

We do not anticipate declaring or paying in the foreseeable future any cash dividends on our common stock. However, if we do make distributions on the Securities, such distributions of cash or property on the Securities will constitute dividends for U.S. federal income tax purposes to the extent paid from our current or accumulated earnings and profits, as determined under U.S. federal income tax principles. Distributions in excess of our current and accumulated earnings and profits will first constitute a return of capital and be applied against and reduce a non-U.S. holder's adjusted tax basis in its Securities, but not below zero. Any excess will be treated as capital gain and will be treated as described below in the section relating to the sale or disposition of the Securities. Because we may not know the extent to which a distribution is a dividend for U.S. federal income tax purposes at the time it is made, for purposes of the withholding rules discussed below we or the applicable withholding agent may treat the entire distribution as a dividend.

Subject to the discussions below regarding backup withholding and foreign accounts, dividends paid to a non-U.S. holder of the Securities that are not effectively connected with the non-U.S. holder's conduct of a trade or business within the United States will be subject to U.S. federal withholding tax at a rate of 30% of the gross amount of the dividends (or such lower rate specified by an applicable income tax treaty).

Non-U.S. holders will be entitled to a reduction in or an exemption from withholding on dividends as a result of either (a) an applicable income tax treaty or (b) the non-U.S. holder holding the Securities in connection with the conduct of a trade or business within the United States and dividends being effectively connected with that trade or business. To claim such a reduction in or exemption from withholding, the non-U.S. holder must provide the applicable withholding agent with a properly executed (a) IRS Form W-8BEN or W-8BEN-E (or other applicable documentation) claiming an exemption from or reduction of the withholding tax under the benefit of an income tax treaty between the United States and the country in which the non-U.S. holder resides or is established, or (b) IRS Form W-8ECI stating that the dividends are not subject to withholding tax because they are effectively connected with the conduct by the non-U.S. holder of a trade or business within the United States, as may be applicable. These certifications must be provided to the applicable withholding agent prior to the payment of dividends and may need to be updated periodically. Non-U.S. holders that do not timely provide the applicable withholding agent with the required certification, but that qualify for a reduced rate under an applicable income tax treaty, may obtain a refund of any excess amounts withheld by timely filing an appropriate claim for refund with the IRS.

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If dividends paid to a non-U.S. holder are effectively connected with the non-U.S. holder's conduct of a trade or business within the United States (and, if required by an applicable income tax treaty, the non-U.S. holder maintains a permanent establishment in the United States to which such dividends are attributable), then, although exempt from U.S. federal withholding tax (provided the non-U.S. holder provides appropriate certification, as described above), the non-U.S. holder will be subject to U.S. federal income tax on such dividends on a net income basis at the regular rates applicable to U.S. persons. In addition, a non-U.S. holder that is a corporation may be subject to a branch profits tax at a rate of 30% (or such lower rate specified by an applicable income tax treaty) on its effectively connected earnings and profits for the taxable year that are attributable to such dividends, as adjusted for certain items. Non-U.S. holders should consult their tax advisors regarding their entitlement to benefits under any applicable income tax treaty.

***Sale or Other Taxable Disposition of the Securities***

Subject to the discussions below on backup withholding and foreign accounts, a non-U.S. holder will not be subject to U.S. federal income tax on any gain realized upon the sale or other disposition of the Securities unless:

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;• the gain is effectively connected with the non-U.S. holder's conduct of a
trade or business within the United States (and, if required by an applicable income tax treaty, the non-U.S. holder maintains a permanent establishment in the United States to which such gain is
attributable);

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;• the non-U.S. holder is a nonresident alien individual present in the United States
for 183 days or more during the taxable year of the disposition and certain other requirements are met; or

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;• the Securities constitute U.S. real property interests, or USRPIs, by reason of our status as a U.S. real property holding
corporation, or USRPHC, for U.S. federal income tax purposes at any time within the shorter of the five-year period preceding the disposition or the non-U.S. holder's holding period for our Securities,
and our common stock is not regularly traded on an established securities market as defined by applicable Treasury Regulations (although holders of pre-funded warrants are urged to consult their own tax
advisors regarding application of the "regularly traded" exception from USRPI status if we are a USRPHC).

Gain described in the first bullet point above will generally be subject to U.S. federal income tax on a net income basis at the regular rates applicable to U.S. persons. A non-U.S. holder that is a foreign corporation also may be subject to a branch profits tax at a rate of 30% (or such lower rate specified by an applicable income tax treaty) on such effectively connected gain, as adjusted for certain items.

A non-U.S. holder described in the second bullet point above will be subject to U.S. federal income tax at a rate of 30% (or such lower rate specified by an applicable income tax treaty) on any gain realized upon the sale or other taxable disposition of the Securities, which may be offset by certain U.S. source capital losses of the non-U.S. holder (even though the individual is not considered a resident of the United States) provided the non-U.S. holder has timely filed U.S. federal income tax returns with respect to such losses.

With respect to the third bullet point above, we believe we are not currently and do not anticipate becoming a USRPHC. Because the determination of whether we are a USRPHC depends on the fair market value of our USRPIs relative to the fair market value of our other business assets and our non-U.S. real property interests, however, there can be no assurance we are not a USRPHC or will not become one in the future.

Non-U.S. holders should consult their tax advisors regarding potentially applicable income tax treaties that may provide for different rules.

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***Constructive Dividends on Pre-funded Warrants***

A non-U.S. holder of pre-funded warrants can be treated as receiving deemed payment of a taxable dividend under certain circumstances as a result of an adjustment or the non-occurrence of an adjustment to the exercise price or number of shares of common stock issuable upon exercise of the pre-funded warrant. Any resulting withholding tax attributable to deemed dividends may be collected from other amounts payable or distributable to the non-U.S. holder. Non-U.S. holders should consult their tax advisors regarding the proper treatment of any adjustments to the pre-funded warrants.

***Information Reporting and Backup Withholding***

A non-U.S. holder will not be subject to backup withholding with respect to distributions on the Securities we make to the non-U.S. holder (including constructive dividends), provided the applicable withholding agent does not have actual knowledge or reason to know such holder is a United States person and the holder certifies its non-U.S. status, such as by providing a valid IRS Form W-8BEN, W-8BEN-E or W-8ECI, or other applicable certification. However, information returns generally will be filed with the IRS in connection with any distributions (including deemed distributions) made on the Securities to the non-U.S. holder, regardless of whether any tax was required to be withheld. Copies of these information returns may also be made available under the provisions of a specific treaty or agreement to the tax authorities of the country in which the non-U.S. holder resides or is established.

Information reporting and backup withholding may apply to the proceeds of a sale or other taxable disposition of the Securities within the United States, and information reporting may (although backup withholding generally will not) apply to the proceeds of a sale or other taxable disposition of the Securities outside the United States conducted through certain U.S.-related financial intermediaries, in each case, unless the beneficial owner certifies under penalty of perjury that it is a non-U.S. holder on IRS Form W-8BEN or W-8BEN-E, or other applicable form (and the payor does not have actual knowledge or reason to know that the beneficial owner is a U.S. person) or such owner otherwise establishes an exemption. Proceeds of a disposition of the Securities conducted through a non-U.S. office of a non-U.S. broker generally will not be subject to backup withholding or information reporting.

Backup withholding is not an additional tax. Any amounts withheld under the backup withholding rules may be allowed as a refund or a credit against a non-U.S. holder's U.S. federal income tax liability, provided the required information is timely furnished to the IRS.

***Additional Withholding Tax on Payments Made to Foreign Accounts***

Withholding taxes may be imposed under the Foreign Account Tax Compliance Act, or FATCA, on certain types of payments made to non-U.S. financial institutions and certain other non-U.S. entities. Specifically, a 30% withholding tax may be imposed on dividends (including deemed dividends) paid on the Securities, or (subject to the proposed Treasury Regulations discussed below) gross proceeds from the sale or other disposition of the Securities paid to a "foreign financial institution" or a "non-financial foreign entity" (each as defined in the Code), unless (1) the foreign financial institution undertakes certain diligence and reporting obligations, (2) the non-financial foreign entity either certifies it does not have any "substantial United States owners" (as defined in the Code) or furnishes identifying information regarding each substantial United States owner, or (3) the foreign financial institution or non-financial foreign entity otherwise qualifies for an exemption from these rules. If the payee is a foreign financial institution and is subject to the diligence and reporting requirements in (1) above, it must enter into an agreement with the U.S. Department of the Treasury requiring, among other things, that it undertake to identify accounts held by certain "specified United States persons" or "United States-owned foreign entities" (each as defined in the Code), annually report certain information about such accounts, and withhold 30% on certain payments to non-compliant foreign

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financial institutions and certain other account holders. Foreign financial institutions located in jurisdictions that have an intergovernmental agreement with the United States governing FATCA may be subject to different rules.

Under the applicable Treasury Regulations and administrative guidance, withholding under FATCA generally applies to payments of dividends (including deemed dividends). Because we may not know the extent to which a distribution (including a deemed distribution) is a dividend for U.S. federal income tax purposes at the time it is made, for purposes of these withholding rules we or the applicable withholding agent may treat the entire distribution as a dividend. While withholding under FATCA would have applied also to payments of gross proceeds from the sale or other disposition of the Securities, proposed Treasury Regulations eliminate FATCA withholding on payments of gross proceeds entirely. Taxpayers generally may rely on these proposed Treasury Regulations until final Treasury Regulations are issued.

Prospective investors should consult their tax advisors regarding the potential application of these withholding provisions.

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**UNDERWRITING** 

The company and the underwriters named below have entered into an underwriting agreement with respect to the shares of common stock being offered. Subject to certain conditions, each underwriter has severally agreed to purchase the number of shares of common stock indicated in the following table. Goldman Sachs & Co. LLC, TD Securities (USA) LLC and Wells Fargo Securities, LLC. are the representatives of the underwriters.

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| | | |
|:---|:---|:---|
| **Underwriters** | **Number of**<br>**Shares** | **Number of**<br>**Pre-Funded**<br>**Warrants** |
|  Goldman Sachs & Co. LLC | 10916827 | 1631250 |
|  TD Securities (USA) LLC | 9160096 | 1368750 |
|  Wells Fargo Securities, LLC | 5019230 | 750000 |
|  Total | 25096153 | 3750000 |

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The underwriters are committed to take and pay for all of the shares of common stock and pre-funded warrants being offered, if any are taken, other than the shares of common stock covered by the option described below unless and until this option is exercised.

The underwriters have an option to buy up to an additional 4,326,922 shares of common stock from the company to cover sales by the underwriters of a greater number of shares of common stock than the total number set forth in the table above. They may exercise that option for 30 days. If any shares of common stock are purchased pursuant to this option, the underwriters will severally purchase shares of common stock in approximately the same proportion as set forth in the table above.

The following table shows the price per share of common stock, or per pre-funded warrant, and total underwriting discounts and commissions to be paid to the underwriters by the company. Such amounts are shown assuming both no exercise and full exercise of the underwriters' option to purchase 4,326,922 additional shares of common stock.

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| | | |
|:---|:---|:---|
| **Paid by the Company** | **No Exercise** | **Full Exercise** |
|  Per Share | $0.156 | $0.156 |
|  Per Pre-Funded Warrant | $0.156 | $0.156 |
|  Total | $4499999.87 | $5174999.70 |

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Shares of common stock sold by the underwriters to the public will initially be offered at the public offering price set forth on the cover of this prospectus supplement. Any shares of common stock or pre-funded warrants sold by the underwriters to securities dealers may be sold at a discount of up to $0.0936 per share of common stock and up to $0.0936 per pre-funded warrant from the public offering price. After the initial offering of the shares of common stock and pre-funded warrants, the representatives may change the offering price and the other selling terms. The offering of the shares of common stock and pre-funded warrants by the underwriters is subject to receipt and acceptance and subject to the underwriters' right to reject any order in whole or in part. The underwriters have not been engaged to act as warrant agent for the pre-funded warrants or to act as underwriter or agent or otherwise participate in the issuance of the shares of our common stock upon the exercise of the pre-funded warrants.

We estimate that the total expenses of this offering, including registration, filing and listing fees, printing fees and legal and accounting expenses, but excluding the underwriting discounts and

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commissions, will be approximately $640,000. Additionally, we have agreed to reimburse the underwriters for their expenses in an amount of up to $35,000, which may be incurred in connection with the review by Financial Industry Regulatory Authority, Inc. of the terms of the shares of common stock and pre-funded warrants offered hereby.

We, our officers, directors and affiliates of our officers and directors have agreed that they will not (i) offer, pledge, sell, contract to sell, sell any option or contract to purchase, purchase any option or contract to sell, grant any option, right or warrant to purchase, lend, or otherwise transfer or dispose of, directly or indirectly, any shares of common stock or any securities convertible into or exercisable or exchangeable for common stock (including, without limitation, common stock or such other securities which may be deemed to be beneficially owned by the undersigned in accordance with the rules and regulations of the SEC and securities which may be issued upon exercise of a stock option or warrant) (collectively, the "Lock-up Securities"), (2) enter into any hedging, swap or other agreement or transaction that transfers, in whole or in part, any of the economic consequences of ownership of the Lock-up Securities, whether any such transaction described in clause (1) or (2) above is to be settled by delivery of common stock or such other securities, in cash or otherwise or (3) make any demand for or exercise any right with respect to the registration of any Lock-up Securities, or (4) publicly disclose the intention to undertake any of the foregoing (and, for the avoidance of doubt, the undersigned hereby waives any and all notice requirements and rights with respect to the registration of any securities pursuant to any agreement, instrument, understanding or otherwise, including any stockholders or registration rights agreement or similar agreement, to which the undersigned is a party or under which the undersigned is entitled to any right or benefit; provided, however, that such waiver shall apply only to the proposed public offering, in each case without the prior written consent of Goldman Sachs & Co. LLC and TD Securities (USA) LLC for a period of 60 days, after the date of this prospectus supplement, other than (A) transfers of shares of common stock as a bona fide gift or gifts, provided that any filing required to be made under Section 16 of the Exchange Act discloses therein that such transfer is a disposition by bona fide gift or otherwise a transfer for no value (and if the transferee is a person, trust or entity that would report a corresponding acquisition of such securities on the undersigned's Form 4, and such acquisition is entitled to be reported on a Form 5, such acquisition may be voluntarily reported on such Form 4), (B) transfers or dispositions of shares of common stock to any trust for the direct or indirect benefit of the undersigned or the immediate family of the undersigned, (C) transfers or dispositions of shares of common stock to any corporation, partnership, limited liability company or other entity all of the beneficial ownership interests of which are held by the undersigned or the immediate family of the undersigned, (D) transfers or dispositions of shares of common stock by will, other testamentary document or intestate succession to the legal representative, heir, beneficiary or a member of the immediate family of the undersigned, (E) distributions of shares of common stock to partners, members or stockholders of the undersigned, (F) transfers to the undersigned's affiliates or to any investment fund or other entity controlled or managed by, controlling or managing, or under common control with, the undersigned, and (G) transfers pursuant to a bona fide third party tender offer, merger, consolidation or other similar transaction made to all holders of the common stock and involving a change of control of the Company approved by the board of directors of the Company, provided that in the event that the tender offer, merger, consolidation or other such transaction is not completed, the common stock owned by the undersigned shall remain subject to the restrictions set forth in the agreed lock-up agreement; provided that in the case of any transfer or distribution pursuant to clause (A), (B), (C), (D), (E) or (F), each transferee, donee or distributee shall execute and deliver to the Representatives the agreed lock-up agreement; and provided, further, that in the case of any transfer, disposition or distribution pursuant to clause (B), (C), (D), (E) or (F) and as otherwise indicated above, no filing by any party (donor, donee, transferor or transferee) under Section 16 of the Exchange Act or other public announcement shall be required or shall be made voluntarily in connection with such transfer or distribution (other than a filing on a Form 5 made after the expiration of the lock-up period referred to above or the filing of a required Schedule 13F or 13G) and any such transfer or distribution shall not involve a disposition for value. The undersigned

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acknowledges and agrees that the foregoing precludes the undersigned from engaging in any hedging or other transactions or arrangements (including, without limitation, any short sale or the purchase or sale of, or entry into, any put or call option, or combination thereof, forward, swap or any other derivative transaction or instrument, however described or defined) designed or intended, or which could reasonably be expected to lead to or result in, a sale or disposition (whether by the undersigned or someone other than the undersigned) or transfer of any economic consequences of ownership, in whole or in part, directly or indirectly, of any shares of Lock-up Securities, whether any such transaction or arrangement (or instrument provided for thereunder) would be settled by delivery of common stock or other securities, in cash or otherwise.

In addition, the foregoing restrictions shall not apply to (i) the exercise on a cash basis of any option to purchase shares of common stock granted under any stock incentive plan or stock purchase plan of the Company disclosed in this prospectus supplement, provided that the underlying shares of common stock shall continue to be subject to the restrictions on transfer set forth in the agreed lock-up agreement, and provided, further, that any required filing under Section 16 of the Exchange Act shall clearly indicate in the footnotes thereto that the filing relates to the circumstances described in this clause (i) above and no other public announcement shall be required or shall be made voluntarily in connection with such transfer or surrender, (ii) establish a trading plan or amend an existing trading plan pursuant to Rule 10b5-1 under the Exchange Act (each such plan, a "Trading Plan") for the transfer of common stock, provided that such Trading Plan does not provide for any transfers, sales or other dispositions of common stock during the lock-up period, and provided, further, that no filing under Section 16 of the Exchange Act or other public announcement shall be made in connection therewith during the lock-up period (other than as required under Item 408 and Item 601 of Regulation S-K) and, to the extent any public announcement or filing under the Exchange Act is required by or on behalf of the undersigned or the Company regarding the establishment or amendment of such trading plan during the lock-up period, such announcement or filing shall include a statement to the effect that no transfer of common stock may be made under such trading plan during the lock-up period, (iii) transfers or dispositions of shares of common stock under a Trading Plan that is existing as of the date hereof, *provided that* no filing under the Exchange Act or other public filing, report or announcement shall be voluntarily made during the lock-up period, and to the extent a public announcement or filing under the Exchange Act, if any, is required to be made by or on behalf of the undersigned, such announcement or filing shall check the appropriate box to indicate that such dispositions were made pursuant to such Trading Plan, (iv) the transfer or dispose of shares of common stock acquired in the public offering or on the open market following the public offering, provided that no filing under Section 16 of the Exchange Act or other public announcement shall be required or shall be made voluntarily in connection with such transfer or disposition during the lock-up period (other than a required filing on a Schedule 13F or 13G), (v) the transfer or dispose of shares of common stock pursuant to any "sell to cover arrangement" for the payment of taxes, including estimated taxes, and remittance payments due as a result of the vesting, settlement or exercise of restricted stock units, options, warrants or other rights to purchase shares of common stock that are scheduled to expire or vest during the lock-up period, as disclosed in writing to the Representatives prior to the date hereof, in all such cases pursuant to equity awards granted under a stock incentive plan or other equity award plan as described in this prospectus supplement, provided that any such common stock received upon such vesting, settlement or exercise shall be subject to the terms set forth in the agreed lock-up agreement and, *provided*, *further*, if the undersigned is required to make a filing under the Exchange Act during the lock-up period, such filing shall include a footnote describing the purpose of the transaction as described in this clause, (vi) transfer or surrender to the Company shares of common stock (or any security convertible into common stock) (a) pursuant to a right of first refusal described in this prospectus supplement with respect to transfers of such shares of common stock or other securities, provided that no filing under Section 16 of the Exchange Act or other public announcement shall be required or shall be made voluntarily in connection with such transfer or disposition during the lock-up period, or (b) to the Company for purposes of exercising or settling

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(including for the payment of tax withholdings due as a result of such exercise or settlement) on a "net exercise," "net settlement" or "cashless" basis any equity award, provided such equity award was granted under a stock incentive plan or stock purchase plan of the Company described in this prospectus supplement, and provided, further, that no filing under Section 16 of the Exchange Act or other public filing, report or announcement shall be voluntarily made during the lock-up period (other than a filing on a Form 5 made after the expiration of the lock-up period referred to above), and if the lock-up party is required to file a report under Section 16 of the Exchange Act during the lock-up period, the lock-up party shall clearly indicate in the footnotes thereto the nature and conditions of such transfer, and (vii) the transfer or disposal of lockup securities by operation of law pursuant to a qualified domestic order or in connection with a divorce settlement or other court order, provided that the recipient of such shares of common stock shall execute and deliver to the Representatives a lock-up letter in the form of the agreed lock-up agreement, provided, further, that any required filing under Section 16 of the Exchange Act shall clearly indicate in the footnotes thereto that the filing relates to the circumstances described in this clause (vii) above.

Goldman Sachs & Co. LLC and TD Securities (USA) LLC may, in their sole discretion and at any time or from time to time before the termination of the 60-day period release all or any portion of the securities subject to lock-up agreements. There are no existing agreements between the underwriters and any of our shareholders who will execute a lock-up agreement, providing consent to the sale of shares of common stock prior to the expiration of the lock-up period.

Our common stock is listed/quoted on the Nasdaq Global Select Market under the symbol "ANNX". We do not intend to list the pre-funded warrants on the Nasdaq Global Select Market or any other national securities exchange or nationally recognized trading system.

The underwriters may also impose a penalty bid. This occurs when a particular underwriter repays to the underwriters a portion of the underwriting discount received by it because the representatives have repurchased shares of common stock sold by or for the account of such underwriter in stabilizing or short covering transactions.

Purchases to cover a short position and stabilizing transactions, as well as other purchases by the underwriters for their own accounts, may have the effect of preventing or retarding a decline in the

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market price of the company's stock, and together with the imposition of the penalty bid, may stabilize, maintain or otherwise affect the market price of the common stock. As a result, the price of the common stock may be higher than the price that otherwise might exist in the open market. The underwriters are not required to engage in these activities and may end any of these activities at any time. These transactions may be effected on the Nasdaq Global Select Market, in the over-the-counter market or otherwise.

**Disclaimers About Non-U.S. Jurisdictions** 

*European Economic Area* 

In relation to each Member State of the European Economic Area (each, a "Relevant Member State"), an offer to the public of any Securities may not be made in that Relevant Member State, except that an offer to the public in that Relevant Member State of any Securities may be made at any time under the following exemptions under the EU Prospectus Regulation:

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;a) to any legal entity which is a "qualified investor" as defined under the EU Prospectus Regulation;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;b) to fewer than 150 natural or legal persons (other than "qualified investors" as defined under the EU
Prospectus Regulation), subject to obtaining the prior consent of the Underwriters for any such offer; or

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;c) in any other circumstances falling within Article 1(4) of the EU Prospectus Regulation,

provided that no such offer of Securities shall result in a requirement for the Company or any of the Underwriters to publish a prospectus pursuant to Article 3 of the Prospectus Regulation or a supplemental prospectus pursuant to Article 23 of the Prospectus Regulation and each person who initially acquires any Securities or to whom any offer is made will be deemed to have represented, warranted and agreed to and with each of the Underwriters and the Company that it is a qualified investor within the meaning of Article 2 of the EU Prospectus Regulation.

In the case of any Securities being offered to a financial intermediary as that term is used in Article 1(4) of the EU Prospectus Regulation, each financial intermediary will also be deemed to have represented, warranted and agreed that the Securities acquired by it in the offer have not been acquired on a non-discretionary basis on behalf of, nor have they been acquired with a view to their offer or resale to, persons in circumstances which may give rise to an offer of any Securities to the public, other than their offer or resale in a Relevant Member State to qualified investors as so defined or in circumstances in which the prior consent of the Underwriters has been obtained to each such proposed offer or resale. The Company, the Underwriters and their affiliates will rely upon the truth and accuracy of the foregoing representations, warranties and agreements. Notwithstanding the above, a person who is not a "qualified investor" and who has notified the Underwriters of such fact in writing may, with the prior consent of the Notwithstanding the above, a person who is not a "qualified investor" and who has notified the Underwriters of such fact in writing may, with the prior consent of the Underwriters, be permitted to acquire Securities in the offer.

For the purposes of this provision, the expression an "offer to the public" in relation to any Securities in any Relevant Member State means the communication in any form and by any means of sufficient information on the terms of the offer and any Securities to be offered so as to enable an investor to decide to purchase or subscribe for any Securities, and the expression "EU Prospectus Regulation" means Regulation (EU) 2017/1129.

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*United Kingdom* 

An offer to the public of any Securities may not be made in the United Kingdom, except that an offer to the public in the United Kingdom of any Securities may be made at any time under the following exemptions under the UK Prospectus Regulation:

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;a) to any legal entity which is a "qualified investor" as defined under the UK Prospectus Regulation;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;b) to fewer than 150 natural or legal persons (other than "qualified investors" as defined under the UK
Prospectus Regulation), subject to obtaining the prior consent of the Underwriters for any such offer; or

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;c) in any other circumstances falling within section 86 of the Financial Services and Markets Act 2000 (as amended,
"FSMA"),

provided that no such offer of Securities shall result in a requirement for the Company or any Underwriter to publish a prospectus pursuant to section 85 of the FSMA or a supplemental prospectus pursuant to Article 23 of the UK Prospectus Regulation and each person who initially acquires any Securities or to whom any offer is made will be deemed to have represented, warranted and agreed to and with each of the Underwriters and the Company that it is a qualified investor within the meaning of Article 2 of the UK Prospectus Regulation.

In the case of any Securities being offered to a financial intermediary as that term is used in Article 1(4) of the UK Prospectus Regulation, each financial intermediary will also be deemed to have represented, warranted and agreed that the Securities acquired by it in the offer have not been acquired on a non-discretionary basis on behalf of, nor have they been acquired with a view to their offer or resale to, persons in circumstances which may give rise to an offer of any Securities to the public, other than their offer or resale in the United Kingdom to qualified investors as so defined or in circumstances in which the prior consent of the Underwriters has been obtained to each such proposed offer or resale.

The Company, the Underwriters and their affiliates will rely upon the truth and accuracy of the foregoing representations, warranties and agreements. Notwithstanding the above, a person who is not a "qualified investor" and who has notified the Underwriters of such fact in writing may, with the prior consent of the Underwriters, be permitted to acquire Securities in the offer.

For the purposes of this provision, the expression an "offer to the public" in relation to any Securities in the United Kingdom means the communication in any form and by any means of sufficient information on the terms of the offer and any Securities to be offered so as to enable an investor to decide to purchase or subscribe for any Securities.

This Prospectus is only being distributed to and is only directed at: (A) persons who are outside the United Kingdom; or (B) qualified investors who are also (i) investment professionals falling within Article 19(5) of the Financial Services and Markets Act 2000 (Financial Promotion) Order 2005 (the "Order"), or (ii) high net worth companies, and other persons to whom it may lawfully be communicated, falling within Article 49(2)(a) to (d) of the Order (all such persons falling within (1)-(3) together being referred to as "relevant persons"). The Securities are only available to, and any invitation, offer or agreement to subscribe, purchase or otherwise acquire the Securities will be engaged in only with, relevant persons. Any person who is not a relevant person should not act or rely on this Prospectus or any of its contents.

*Canada* 

The securities may be sold in Canada only to purchasers purchasing, or deemed to be purchasing, as principal that are accredited investors, as defined in National Instrument 45-106

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Prospectus Exemptions or subsection 73.3(1) of the Securities Act (Ontario), and are permitted clients, as defined in National Instrument 31-103 Registration Requirements, Exemptions, and Ongoing Registrant Obligations. Any resale of the securities must be made in accordance with an exemption form, or in a transaction not subject to, the prospectus requirements of applicable securities laws.

Securities legislation in certain provinces or territories of Canada may provide a purchaser with remedies for rescission or damages if this offering memorandum (including any amendment thereto) contains a misrepresentation, provided that the remedies for rescission or damages are exercised by the purchaser within the time limit prescribed by the securities legislation of the purchaser's province or territory. The purchaser should refer to any applicable provisions of the securities legislation of the purchaser's province or territory of these rights or consult with a legal advisor.

Pursuant to section 3A.3 of National Instrument 33-105 Underwriting Conflicts (NI 33-105), the underwriters are not required to comply with the disclosure requirements of NI 33-105 regarding underwriter conflicts of interest in connection with this offering.

*Hong Kong* 

The shares may not be offered or sold in Hong Kong by means of any document other than (i) in circumstances which do not constitute an offer to the public within the meaning of the Companies (Winding Up and Miscellaneous Provisions) Ordinance (Cap. 32 of the Laws of Hong Kong) ("Companies (Winding Up and Miscellaneous Provisions) Ordinance") or which do not constitute an invitation to the public within the meaning of the Securities and Futures Ordinance (Cap. 571 of the Laws of Hong Kong) ("Securities and Futures Ordinance"), or (ii) to "professional investors" as defined in the Securities and Futures Ordinance and any rules made thereunder, or (iii) in other circumstances which do not result in the document being a "prospectus" as defined in the Companies (Winding Up and Miscellaneous Provisions) Ordinance, and no advertisement, invitation or document relating to the shares may be issued or may be in the possession of any person for the purpose of issue (in each case whether in Hong Kong or elsewhere), which is directed at, or the contents of which are likely to be accessed or read by, the public in Hong Kong (except if permitted to do so under the securities laws of Hong Kong) other than with respect to shares which are or are intended to be disposed of only to persons outside Hong Kong or only to "professional investors" in Hong Kong as defined in the Securities and Futures Ordinance and any rules made thereunder.

*Singapore* 

This prospectus supplement has not been registered as a prospectus with the Monetary Authority of Singapore. Accordingly, this prospectus supplement and any other document or material in connection with the offer or sale, or invitation for subscription or purchase, of the shares may not be circulated or distributed, nor may the shares be offered or sold, or be made the subject of an invitation for subscription or purchase, whether directly or indirectly, to persons in Singapore other than (i) to an institutional investor (as defined under Section 4A of the Securities and Futures Act, Chapter 289 of Singapore (the "SFA")) under Section 274 of the SFA, (ii) to a relevant person (as defined in Section 275(2) of the SFA) pursuant to Section 275(1) of the SFA, or any person pursuant to Section 275(1A) of the SFA, and in accordance with the conditions specified in Section 275 of the SFA or (iii) otherwise pursuant to, and in accordance with the conditions of, any other applicable provision of the SFA, in each case subject to conditions set forth in the SFA.

Where the shares are subscribed or purchased under Section 275 of the SFA by a relevant person which is a corporation (which is not an accredited investor (as defined in Section 4A of the SFA)) the sole business of which is to hold investments and the entire share capital of which is owned by one or more individuals, each of whom is an accredited investor, the securities (as defined in

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Section 239(1) of the SFA) of that corporation shall not be transferable for 6 months after that corporation has acquired the shares under Section 275 of the SFA except: (1) to an institutional investor under Section 274 of the SFA or to a relevant person (as defined in Section 275(2) of the SFA), (2) where such transfer arises from an offer in that corporation's securities pursuant to Section 275(1A) of the SFA, (3) where no consideration is or will be given for the transfer, (4) where the transfer is by operation of law, (5) as specified in Section 276(7) of the SFA, or (6) as specified in Regulation 32 of the Securities and Futures (Offers of Investments) (Shares and Debentures) Regulations 2005 of Singapore ("Regulation 32")

Where the shares are subscribed or purchased under Section 275 of the SFA by a relevant person which is a trust (where the trustee is not an accredited investor (as defined in Section 4A of the SFA)) whose sole purpose is to hold investments and each beneficiary of the trust is an accredited investor, the beneficiaries' rights and interest (howsoever described) in that trust shall not be transferable for 6 months after that trust has acquired the shares under Section 275 of the SFA except: (1) to an institutional investor under Section 274 of the SFA or to a relevant person (as defined in Section 275(2) of the SFA), (2) where such transfer arises from an offer that is made on terms that such rights or interest are acquired at a consideration of not less than S$200,000 (or its equivalent in a foreign currency) for each transaction (whether such amount is to be paid for in cash or by exchange of securities or other assets), (3) where no consideration is or will be given for the transfer, (4) where the transfer is by operation of law, (5) as specified in Section 276(7) of the SFA, or (6) as specified in Regulation 32.

*Japan* 

The securities have not been and will not be registered under the Financial Instruments and Exchange Act of Japan (Act No. 25 of 1948, as amended), or the FIEA. The securities may not be offered or sold, directly or indirectly, in Japan or to or for the benefit of any resident of Japan (including any person resident in Japan or any corporation or other entity organized under the laws of Japan) or to others for reoffering or resale, directly or indirectly, in Japan or to or for the benefit of any resident of Japan, except pursuant to an exemption from the registration requirements of the FIEA and otherwise in compliance with any relevant laws and regulations of Japan.

*Brazil* 

THE OFFER AND SALE OF THE SECURITIES HAVE NOT BEEN AND WILL NOT BE REGISTERED WITH THE BRAZILIAN SECURITIES COMMISSION (COMISSÃO DE VALORES MOBILIÁRIOS, OR "**CVM**") AND, THEREFORE, WILL NOT BE CARRIED OUT BY ANY MEANS THAT WOULD CONSTITUTE A PUBLIC OFFERING IN BRAZIL UNDER CVM RESOLUTION NO 160, DATED 13 JULY 2022, AS AMENDED ("**CVM RESOLUTION 160**") OR UNAUTHORIZED DISTRIBUTION UNDER BRAZILIAN LAWS AND REGULATIONS. THE SECURITIES MAY ONLY BE OFFERED TO BRAZILIAN PROFESSIONAL INVESTORS (AS DEFINED BY APPLICABLE CVM REGULATION), WHO MAY ONLY ACQUIRE THE SECURITIES THROUGH A NON-BRAZILIAN ACCOUNT, WITH SETTLEMENT OUTSIDE BRAZIL IN NON-BRAZILIAN CURRENCY. THE TRADING OF THESE SECURITIES ON REGULATED SECURITIES MARKETS IN BRAZIL IS PROHIBITED.

The Company has agreed to indemnify the several underwriters against certain liabilities, including liabilities under the Securities Act of 1933.

The underwriters and their respective affiliates are full service financial institutions engaged in various activities, which may include sales and trading, commercial and investment banking, advisory,

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investment management, investment research, principal investment, hedging, market making, brokerage and other financial and non-financial activities and services. Certain of the underwriters and their respective affiliates have provided, and may in the future provide, a variety of these services to the issuer and to persons and entities with relationships with the issuer, for which they received or will receive customary fees and expenses.

In the ordinary course of their various business activities, the underwriters and their respective affiliates, officers, directors and employees may purchase, sell or hold a broad array of investments and actively trade securities, derivatives, loans, commodities, currencies, credit default swaps and other financial instruments for their own account and for the accounts of their customers, and such investment and trading activities may involve or relate to assets, securities and/or instruments of the issuer (directly, as collateral securing other obligations or otherwise) and/or persons and entities with relationships with the issuer. The underwriters and their respective affiliates may also communicate independent investment recommendations, market color or trading ideas and/or publish or express independent research views in respect of such assets, securities or instruments and may at any time hold, or recommend to clients that they should acquire, long and/or short positions in such assets, securities and instruments.

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**LEGAL MATTERS** 

The validity of the issuance of the securities offered in this prospectus supplement will be passed upon for us by Cooley LLP, New York, New York. Certain legal matters in connection with this offering will be passed upon for the underwriters by Latham & Watkins LLP, New York, New York.

**EXPERTS** 

The consolidated financial statements of Annexon, Inc. as of December 31, 2024 and 2023, and for each of the years in the two-year period ended December 31, 2024, have been incorporated by reference herein and in the registration statement in reliance upon the report of KPMG LLP, independent registered public accounting firm, incorporated by reference herein, and upon the authority of said firm as experts in accounting and auditing.

**WHERE YOU CAN FIND ADDITIONAL INFORMATION** 

We have filed with the SEC a registration statement on Form S-3 (File No. 333-278246) under the Securities Act, of which this prospectus supplement forms a part. The rules and regulations of the SEC allow us to omit from this prospectus supplement and the accompanying prospectus certain information included in the registration statement. For further information about us and the securities we are offering under this prospectus supplement and the accompanying prospectus, you should refer to the registration statement and the exhibits and schedules filed with the registration statement. With respect to the statements contained in this prospectus supplement and the accompanying prospectus regarding the contents of any agreement or any other document, in each instance, the statement is qualified in all respects by the complete text of the agreement or document, a copy of which has been filed as an exhibit to the registration statement.

We file reports, proxy statements and other information with the SEC under the Exchange Act. The SEC maintains an Internet website that contains reports, proxy statements and other information about issuers, like us, that file electronically with the SEC. The address of that website is http://www.sec.gov.

Information about us is also available at our website at http://www.annexonbio.com. Information contained on, or accessible through, our website shall not be deemed incorporated into and is not a part of this prospectus supplement or the registration statement of which it forms a part. We have included our website in this prospectus supplement solely as an inactive textual reference.

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**INCORPORATION OF CERTAIN INFORMATION BY REFERENCE** 

The SEC's rules allow us to "incorporate by reference" information into this prospectus supplement, which means that we can disclose important information to you by referring you to another document filed separately with the SEC. The information incorporated by reference is deemed to be part of this prospectus supplement, and subsequent information that we file with the SEC (Commission File No. 001-39402) will automatically update and supersede that information. Any statement contained in this prospectus supplement or a previously filed document incorporated by reference will be deemed to be modified or superseded for purposes of this prospectus supplement to the extent that a statement contained in this prospectus supplement or a subsequently filed document incorporated by reference modifies or replaces that statement.

This prospectus supplement incorporates by reference the documents set forth below that have previously been filed with the SEC:

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;• our Annual Report on [Form 10-K](http://www.sec.gov/Archives/edgar/data/../../../ix?doc=/Archives/edgar/data/0001528115/000095017025030849/annx-20241231.htm) for the year ended December 31, 2024, filed with the SEC on March 3, 2025;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;• our Quarterly Report on Form 10-Q for the quarters ended March 31, 2025,
June 30, 2025 and September 30, 2025, filed with the SEC on [May 12, 2025](http://www.sec.gov/Archives/edgar/data/../../../ix?doc=/Archives/edgar/data/0001528115/000095017025069200/annx-20250331.htm) , [August 14, 2025](http://www.sec.gov/Archives/edgar/data/../../../ix?doc=/Archives/edgar/data/0001528115/000095017025108869/annx-20250630.htm) and [November 10, 2025](http://www.sec.gov/Archives/edgar/data/../../../ix?doc=/Archives/edgar/data/1528115/000119312525274240/annx-20250930.htm) , respectively;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;• our Current Reports on Form 8-K (other than information furnished rather than
filed), filed with the SEC on [January 10, 2025](http://www.sec.gov/Archives/edgar/data/../../../ix?doc=/Archives/edgar/data/0001528115/000119312525004133/d796195d8k.htm) , [January 13, 2025](http://www.sec.gov/Archives/edgar/data/../../../ix?doc=/Archives/edgar/data/0001528115/000119312525005009/d38866d8k.htm) , [June 9, 2025](http://www.sec.gov/Archives/edgar/data/../../../ix?doc=/Archives/edgar/data/0001528115/000119312525137810/d935876d8k.htm) and [June 25, 2025](http://www.sec.gov/Archives/edgar/data/../../../ix?doc=/Archives/edgar/data/0001528115/000119312525147005/d949875d8k.htm) ;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;• the information specifically incorporated by reference in the Company's Annual Report on Form 10-K for the year ended December 31, 2024 from the Company's Definitive Proxy Statement on Schedule 14A, relating to the Company's 2025 Annual Meeting of Stockholders, which was filed with the SEC
on [April 23, 2025](http://www.sec.gov/Archives/edgar/data/../../../ix?doc=/Archives/edgar/data/0001528115/000114036125015175/ny20043084x1_def14a.htm) ; and

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;• the description of our common stock which is registered under Section 12 of the Exchange Act, in our registration
statement on [Form 8-A](http://www.sec.gov/Archives/edgar/data/1528115/000119312520196463/d90014d8a12b.htm) , filed on July 21, 2020, including any amendment or reports filed for the purposes of
updating this description, including [Exhibit 4.3](http://www.sec.gov/Archives/edgar/data/0001528115/000156459022008044/annx-ex43_9.htm) to our Annual Report on Form 10-K for the year ended
December 31, 2021, filed with the SEC on March 1, 2022.

All reports and other documents we subsequently file pursuant to Section 13(a), 13(c), 14 or 15(d) of the Exchange Act prior to the termination of this offering, including all such documents we may file with the SEC after the date of the initial registration statement and prior to the effectiveness of the registration statement, but excluding any information furnished to, rather than filed with, the SEC, will also be incorporated by reference into this prospectus supplement and deemed to be part of this prospectus supplement from the date of the filing of such reports and documents.

You may request a free copy of any of the documents incorporated by reference in this prospectus supplement by writing or telephoning us at the following address:

Annexon, Inc.

1400 Sierra Point Parkway, Bldg C, Suite 200

Brisbane, California 94005

(650) 822-5500

Attention: Investor Relations

Exhibits to the filings will not be sent, however, unless those exhibits have specifically been incorporated by reference in this prospectus supplement.

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**PROSPECTUS**![LOGO](g34136g01g01.jpg)

**$400,000,000** 

**Common Stock** 

**Preferred Stock** 

**Debt Securities** 

**Warrants** 

**Units** 

From time to time, we may offer and sell up to an aggregate amount of $400,000,000 of any combination of shares of our common stock, shares of our preferred stock, debt securities, warrants and units to purchase any of such securities, in one or more offerings at prices and on terms described in this prospectus. We may also offer securities as may be issuable upon conversion, redemption, repurchase, exchange or exercise of any securities registered hereunder, including any applicable antidilution provisions.

This prospectus provides a general description of the securities we may offer. Each time we offer securities, we will provide the specific terms of the securities offered in one or more supplements to this prospectus. We may also authorize one or more free writing prospectuses to be provided to you in connection with these offerings. The prospectus supplement and any related free writing prospectus may also add, update or change information contained in this prospectus. You should carefully read this prospectus, the applicable prospectus supplement and any related free writing prospectus, as well as any documents incorporated by reference, before you invest in any of the securities being offered.

Our common stock is listed on the Nasdaq Global Select Market under the trading symbol "ANNX." On March 25, 2024, the last reported sale price of our common stock was $6.64 per share. The applicable prospectus supplement will contain information, where applicable, as to other listings, if any, on the Nasdaq Global Select Market or other securities market or other exchange of the securities, if any, covered by the applicable prospectus supplement.

We may sell these securities directly to investors, through agents designated from time to time or to or through underwriters or dealers, on a continuous or delayed basis. For additional information on the methods of sale, you should refer to the section titled "Plan of Distribution" in this prospectus. If any agents or underwriters are involved in the sale of any securities with respect to which this prospectus is being delivered, the names of such agents or underwriters and any applicable fees, commissions, discounts and options to purchase additional shares will be set forth in a prospectus supplement. The price to the public of such securities and the net proceeds we expect to receive from such sale will also be set forth in a prospectus supplement.

**Investing in our securities involves a high degree of risk. Before making an investment decision, you should review carefully the risks and uncertainties described under the section titled "[Risk Factors](#tx34136_3)" on page 9 of this prospectus and any similar section contained in the applicable prospectus supplement and in any free writing prospectuses we have authorized for use in connection with a specific offering, and under similar headings in the other documents that are incorporated by reference into this prospectus.** 

**Neither the Securities and Exchange Commission nor any state securities commission has approved or disapproved of these securities or determined if this prospectus is truthful or complete. Any representation to the contrary is a criminal offense.** 

**The date of this prospectus is April 1, 2024.** 

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**TABLE OF CONTENTS** 

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| | |
|:---|:---|
|  | **Page** |
|  [ABOUT THIS PROSPECTUS](#tx34136_1) | 1 |
|  [PROSPECTUS SUMMARY](#tx34136_2) | 3 |
|  [RISK FACTORS](#tx34136_3) | 9 |
|  [SPECIAL NOTE REGARDING FORWARD-LOOKING STATEMENTS](#tx34136_4) | 10 |
|  [USE OF PROCEEDS](#tx34136_5) | 12 |
|  [DESCRIPTION OF CAPITAL STOCK](#tx34136_6) | 13 |
|  [DESCRIPTION OF DEBT SECURITIES](#tx34136_7) | 19 |
|  [DESCRIPTION OF WARRANTS](#tx34136_8) | 26 |
|  [DESCRIPTION OF UNITS](#tx34136_9) | 29 |
|  [LEGAL OWNERSHIP OF SECURITIES](#tx34136_10) | 30 |
|  [PLAN OF DISTRIBUTION](#tx34136_11) | 34 |
|  [LEGAL MATTERS](#tx34136_12) | 37 |
|  [EXPERTS](#tx34136_13) | 37 |
|  [WHERE YOU CAN FIND MORE INFORMATION](#tx34136_14) | 37 |
|  [INCORPORATION BY REFERENCE](#tx34136_15) | 37 |

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**ABOUT THIS PROSPECTUS** 

This prospectus is part of a registration statement on Form S-3 that we have filed with the Securities and Exchange Commission (the "SEC"), using a "shelf" registration process under the Securities Act of 1933, as amended (the "Securities Act"). Under this shelf registration statement, we may, from time to time, offer and sell, either individually or in combination, in one or more offerings, up to a total aggregate offering amount of $400,000,000 of any combination of the securities described in this prospectus.

This prospectus provides you with a general description of the securities we may offer. Each time we offer securities under this prospectus, we will provide a prospectus supplement that will contain more specific information about the terms of that offering. We may also authorize one or more free writing prospectuses to be provided to you that may contain material information relating to these offerings. The prospectus supplement and any related free writing prospectus that we may authorize to be provided to you may also add, update or change any of the information contained in this prospectus or in the documents that we have incorporated by reference into this prospectus. We urge you to read carefully this prospectus, any applicable prospectus supplement and any free writing prospectuses we may authorize for use in connection with a specific offering, together with the documents incorporated by reference into this prospectus as described under the sections titled "Where You Can Find More Information" and "Incorporation of Certain Information by Reference," before investing in any of the securities being offered.

**This prospectus may not be used to consummate a sale of securities unless it is accompanied by a prospectus supplement.** 

Neither we, nor any agent, underwriter or dealer has authorized any other person to provide you with any information other than that contained or incorporated by reference in this prospectus, any related prospectus supplement and any related free writing prospectus that we may authorize to be provided to you. We take no responsibility for, and can provide no assurance as to the reliability of, any other information that others may give you. We are not making an offer to sell or soliciting an offer to buy our securities in any jurisdiction in which an offer or solicitation is not authorized or in which the person making that offer or solicitation is not qualified to do so or to anyone to whom it is unlawful to make an offer or solicitation. You should assume that the information contained in this prospectus, any related prospectus supplement and in any free writing prospectus that we may authorize for use in connection with this offering and the documents incorporated by reference into this prospectus is accurate only as of the date of those respective documents, regardless of the time of delivery of the respective document or of any sale of securities covered by this prospectus. Our business, financial condition, results of operations and prospects may have changed since those dates. You should not assume that the information contained in or incorporated by reference in this prospectus, in any related prospectus supplement or in any free writing prospectus that we may authorize for use in connection with this offering, is accurate as of any date other than the respective dates thereof. You should read this prospectus, any related prospectus supplement, any free writing prospectus that we may authorize for use in connection with this offering and the documents incorporated by reference into this prospectus as described under the sections titled "Where You Can Find More Information" and "Incorporation by Reference" in their entirety before making an investment decision.

We are offering to sell, and seeking offers to buy, our securities only in jurisdictions where offers and sales are permitted. The distribution of this prospectus, any related prospectus supplement and any free writing prospectus we may authorize and the offering of our securities in certain jurisdictions may be restricted by law. Persons outside the United States who come into possession of this prospectus, any related prospectus supplement and any free writing prospectus we may authorize must inform themselves about, and observe any restrictions relating to, the offering of our securities and the distribution of this prospectus, any related prospectus supplement and any free writing prospectus we may authorize outside the United States. This prospectus, any related prospectus supplement and any free writing prospectus we may authorize does not constitute, and may not be used in connection with, an offer to sell, or a solicitation of an offer to buy, any securities offered by this

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prospectus, any related prospectus supplement and any free writing prospectus we may authorize by any person in any jurisdiction in which it is unlawful for such person to make such an offer or solicitation. This prospectus contains and incorporates by reference market data and industry statistics and forecasts that are based on independent industry publications and other publicly available information. Although we believe that these sources are reliable, we do not guarantee the accuracy or completeness of this information and we have not independently verified this information. Although we are not aware of any misstatements regarding the market and industry data presented in this prospectus and the documents incorporated herein by reference, these estimates involve risks and uncertainties and are subject to change based on various factors, including those discussed under the section titled "Risk Factors" contained in the applicable prospectus supplement and any related free writing prospectus, and under similar headings in the other documents that are incorporated by reference into this prospectus. Accordingly, investors should not place undue reliance on this information.

This prospectus and the information incorporated herein by reference contain summaries of certain provisions contained in some of the documents described herein, but reference is made to the actual documents for complete information. All of the summaries are qualified in their entirety by the actual documents. Copies of some of the documents referred to herein have been filed, will be filed or will be incorporated by reference as exhibits to the registration statement of which this prospectus is a part, and you may obtain copies of those documents as described below under sections titled "Where You Can Find More Information" and "Incorporation by Reference."

When we refer to "Annexon," "we," "our," "us" and the "Company" in this prospectus, we mean Annexon, Inc. and its consolidated subsidiary, unless otherwise specified. When we refer to "you," we mean the potential holders of the applicable series of securities.

"Annexon", "Annexon Biosciences", the Annexon logo and other trade names, trademarks or service marks of Annexon are the property of Annexon, Inc. This prospectus also contains references to our trademarks and to trademarks belonging to other entities. Trade names, trademarks and service marks of other companies appearing in this report are the property of their respective holders. We do not intend our use or display of other companies' trade names or trademarks to imply a relationship with, or endorsement or sponsorship of us by, any other companies. Solely for convenience, the trade names and trademarks may be referred to without the <sup>®</sup> and <sup>™</sup> symbols, but such references should not be construed as any indicator that their respective owners will not assert their rights thereto.

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**PROSPECTUS SUMMARY** 

*This summary highlights selected information appearing elsewhere in this prospectus or incorporated by reference in this prospectus, and does not contain all of the information that you need to consider in making your investment decision. You should carefully read the entire prospectus, the applicable prospectus supplement and any related free writing prospectus, including the risks of investing in our securities discussed under the section titled "Risk Factors" contained in the applicable prospectus supplement and any related free writing prospectus, and under similar headings in the other documents that are incorporated by reference into this prospectus and the applicable prospectus supplement. You should also carefully read the information incorporated by reference into this prospectus, including our financial statements, and the exhibits to the registration statement of which this prospectus is a part.* 

*Except as otherwise indicated herein or as the context otherwise requires, references in this prospectus to "Annexon," "the Company," "we," "us," "our" and similar references refer to Annexon, Inc., a corporation under the laws of the State of Delaware and its consolidated subsidiaries, if any, unless otherwise specified.* 

**Company Overview** 

We are a clinical-stage biopharmaceutical company pioneering a new class of complement medicines for people living with devastating inflammatory-related diseases. The classical complement pathway is a core component to the body's immune system that activates a powerful inflammatory cascade. We believe that by stopping the classical complement pathway at its start by targeting C1q, the initiating molecule of the classical complement pathway, our approach may have the potential to provide more complete protection against complement-mediated disorders of the body, brain and eye.

Using our proprietary platform, we are identifying and characterizing the role of the classical complement pathway in three therapeutic areas—autoimmune, neurodegeneration and ophthalmology. In so doing, we are advancing a pipeline of product candidates designed to block the early classical cascade and all downstream pathway components and their tissue-damaging functions. Our goal is to suppress excessive or aberrant classical complement activity that contributes to chronic inflammation and tissue damage to slow or even halt disease progression, while preserving the beneficial immune functions of the lectin and alternative complement pathways involved in the clearance of pathogens and damaged cells. We have demonstrated robust target engagement in the body, brain and eye, and clinical proof of concept in multiple diseases, and have focused our resources on development of three priority programs:

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;• **Guillain-Barré Syndrome, or GBS:** We are advancing our lead candidate, ANX005, an investigational,
full-length monoclonal antibody, or mAb, formulated for intravenous administration in a pivotal Phase 3 clinical trial for the potential treatment of patients with GBS. GBS is a rare antibody-mediated autoimmune disease that is the most common cause
of acute neuromuscular paralysis, with no therapies in the U.S. approved by the Food and Drug Administration, or FDA. We believe maximum suppression of C1q and the classical cascade early in the disease process may act to rapidly prevent
complement-mediated nerve damage and irreversible neurological disability. In a prior placebo-controlled proof-of-concept trial, a single dose of ANX005 showed rapid and
consistent improvement in muscle strength that translated into observable gains in health status, including a reduction in the need of mechanical ventilation, as well as a reduction in nerve damage and clinical function. We completed enrollment of
241 patients in our ongoing placebo-controlled Phase 3 GBS trial, and data are anticipated in the second quarter of 2024. We intend to establish comparability of the GBS patient population in our Phase 3 trial with patients from the International
Guillain-Barré Syndrome Outcomes Study, or IGOS, a global, prospective, observational, multicenter cohort study that has enrolled 2,000 patients who were followed for one to three years. We have initiated a
real-

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world evidence, or RWE, comparability protocol with IGOS with data anticipated in the first half of 2025 to support our Biologics License Applications, or BLA, submission. ANX005 has been granted Fast Track and orphan drug designation for the treatment of GBS from the FDA. ANX005 has also been granted orphan designation from the European Medicines Agency, or EMA. <br>

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;• **Geographic Atrophy, or GA:** We are advancing ANX007, an antigen-binding fragment, or Fab, formulated for
intravitreal administration, into a pivotal Phase 3 program for the potential treatment of patients with GA. GA is the leading cause of vision loss in the elderly, that affects an estimated eight million people globally. ANX007 is designed to block
C1q locally in the eye, to provide more complete protection against excess classical complement activity, a key driver of GA, and the loss of photoreceptor neurons. In a randomized, multi-center, double-masked, sham-controlled Phase 2 ARCHER
clinical trial of 270 patients with GA, ANX007 was the first and only program to show statistically significant and consistent protection against vision loss in a broad population of patients with GA, measured by best corrected visual acuity, or
BCVA, ≥15-letter loss, the widely accepted and clinically meaningful functional endpoint. While the primary endpoint of rate of lesion growth did not reach statistical significance, evaluating the first
and second six months of ANX007 treatment showed a greater effect on lesion size with time, suggesting that lesion growth may slow with longer treatment with ANX007. In December 2023, we announced FDA alignment on a Phase 3 registration program for
ANX007 in GA using, for the first-time, the prevention of ≥15-letter loss of BCVA as the primary outcome measure. We plan to initiate the Phase 3 ARCHER II trial in mid-2024, a global sham-controlled trial designed to confirm the results from the Phase 2 ARCHER trial. We also plan to initiate the Phase 3 ARROW trial in late 2024, an injection-controlled head-to-head study against SYFOVRE<sup>®</sup> (pegcetacoplan injection) with the potential to underscore ANX007's unique
mechanism of action and critical differentiation on visual function. ANX007 is the first 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.

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;• **ANX1502 for Autoimmune Indications:** We are advancing ANX1502, a novel oral small molecule inhibitor of
classical complement which we believe is first-in-kind. In a Phase 1 single-ascending dose, or SAD, and multiple-ascending dose, or MAD, clinical trial in healthy
volunteers designed to evaluate the safety, tolerability, pharmacokinetics, or PK, and pharmacodynamics, or 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 that support its advancement. We plan to advance a tablet formation of ANX1502 into a proof-of-concept study
designed to assess PD and efficacy in patients with cold agglutinin disease, or CAD, in the first half of 2024, with data expected in the second half of 2024. Following the successful completion of the proof-of-concept study, we intend to evaluate ANX1502 in additional serious complement-mediated autoimmune diseases with the aim of providing enhanced efficacy and offering convenient dosing administration
for long-term treatment of chronic conditions.

We hold worldwide development and commercialization rights, including through exclusive licenses, to all of our product candidates, which allows us to strategically maximize value from our product portfolio over time. Our patent portfolio includes patent protection for our upstream complement platform and each of our product candidates.

**Corporate Information** 

We were incorporated under the laws of the State of Delaware on March 3, 2011. Our principal executive offices are located at 1400 Sierra Point Parkway, Bldg C, Suite 200, Brisbane, California 94005, and our telephone number is (650) 822-5500. Our corporate website address is www.annexonbio.com. Information

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contained on, or accessible through, our website shall not be deemed incorporated into and is not a part of this prospectus or the registration statement of which it forms a part. We have included our website in this prospectus solely as an inactive textual reference.

**Implications of Being a Smaller Reporting Company** 

We are a "smaller reporting company" as defined in the Securities Exchange Act of 1934, as amended ("Exchange Act"), which allows us to take advantage of many of the exemptions available to "emerging growth companies" as defined in the Jumpstart Our Business Startups Act of 2012, including not being required to comply with the auditor attestation requirements of Section 404 of the Sarbanes-Oxley Act and reduced disclosure obligations regarding executive compensation. We will be able to take advantage of the scaled disclosures available to smaller reporting companies for so long as our voting and non-voting common stock held by non-affiliates is less than $250.0 million measured on the last business day of our second fiscal quarter, or our annual revenue is less than $100.0 million during the most recently completed fiscal year and our voting and non-voting common stock held by non-affiliates is less than $700.0 million measured on the last business day of our second fiscal quarter.

**The Securities We May Offer** 

We may offer shares of our common stock and preferred stock, debt securities, warrants to purchase any of such securities, either individually or as units in combination, up to an aggregate offering amount of $400,000,000, from time to time in one or more offerings under this prospectus, together with any applicable prospectus supplement and any related free writing prospectus, at prices and on terms to be determined by market conditions at the time of any offering. We may also offer common stock, preferred stock and/or debt securities upon the exercise of warrants. This prospectus provides you with a general description of the securities we may offer. Each time we offer a type or series of securities under this prospectus, we will provide a prospectus supplement that will describe the specific amounts, prices and other important terms of the securities, including, to the extent applicable:

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;• designation or classification;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;• aggregate principal amount or aggregate offering price;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;• maturity date, if applicable;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;• original issue discount, if any;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;• rates and times of payment of interest or dividends, if any;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;• redemption, conversion, exercise, exchange or sinking fund terms, if any;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;• conversion or exchange prices or rates, if any, and, if applicable, any provisions for changes to or adjustments
in the conversion or exchange prices or rates and in the securities or other property receivable upon conversion or exchange;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;• ranking, if applicable;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;• restrictive covenants, if any;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;• voting or other rights, if any; and

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;• material or special U.S. federal income tax considerations.

The applicable prospectus supplement and any related free writing prospectus that we may authorize to be provided to you may also add, update or change any of the information contained in this prospectus or in the

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documents we have incorporated by reference. However, no prospectus supplement or free writing prospectus will offer a security that is not registered and described in this prospectus at the time of the effectiveness of the registration statement of which this prospectus is a part.

**THIS PROSPECTUS MAY NOT BE USED TO CONSUMMATE A SALE OF SECURITIES UNLESS IT IS ACCOMPANIED BY A PROSPECTUS SUPPLEMENT.** 

We may sell the securities directly to investors or to or through agents, underwriters or dealers. We and our agents or underwriters reserve the right to accept or reject all or part of any proposed purchase of securities. If we do offer securities to or through agents or underwriters, we will include in the applicable prospectus supplement:

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;• the names of those agents or underwriters;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;• applicable fees, discounts and commissions to be paid to them;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;• details regarding over-allotment options, if any; and

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;• the estimated net proceeds to us.

*Common Stock*. We may issue shares of our common stock from time to time. Each holder of our common stock is entitled to one vote for each share on all matters submitted to a vote of the stockholders, including the election of directors. The election of directors by our stockholders shall be determined by a plurality of the votes cast and our stockholders do not have cumulative voting rights in the election of directors. Subject to preferences that may be applicable to any then-outstanding preferred stock, holders of common stock are entitled to receive ratably such dividends, if any, as may be declared from time to time by our board of directors out of legally available funds. In the event of our liquidation, dissolution, or winding up, the holders of common stock will be entitled to share ratably in the assets legally available for distribution to stockholders after the payment of or provision for all of our debts and other liabilities, subject to the prior rights of any preferred stock then-outstanding. Holders of common stock have no preemptive or conversion rights or other subscription rights and there are no redemption or sinking fund provisions applicable to the common stock. The rights, preferences, and privileges of holders of common stock are subject to and may be adversely affected by the rights of the holders of shares of any series of preferred stock that we may designate and issue in the future. In this prospectus, we have summarized certain general features of our common stock under the heading "Description of Capital Stock—Common Stock." We urge you, however, to read the applicable prospectus supplement (and any related free writing prospectus that we may authorize to be provided to you) related to any common stock being offered.

*Preferred Stock*. We may issue shares of our preferred stock from time to time, in one or more series.

Our board of directors may, without further action by our stockholders, fix the rights, preferences, privileges and restrictions of up to an aggregate of 5,000,000 shares of preferred stock in one or more series and authorize their issuance. These rights, preferences and privileges could include dividend rights, conversion rights, voting rights, terms of redemption, liquidation preferences, sinking fund terms and the number of shares constituting any series or the designation of such series, any or all of which may be greater than the rights of our common stock. Any convertible preferred stock we may issue will be convertible into our common stock or exchangeable for other securities. Conversion may be mandatory or at the holder's option and would be at prescribed conversion rates.

If we sell any series of preferred stock under this prospectus, we will fix the designations, voting powers, preferences and rights of such series of preferred stock we issue under this prospectus, as well as the qualifications, limitations or restrictions thereof, in the certificate of designation relating to that series. We will file as an exhibit to the registration statement of which this prospectus is a part, or will incorporate by reference from reports that we file with the SEC, the form of any certificate of designation that contains the terms of the

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series of preferred stock we are offering. In this prospectus, we have summarized certain general features of the preferred stock under the heading "Description of Capital Stock—Preferred Stock." We urge you, however, to read the applicable prospectus supplement (and any free writing prospectus that we may authorize to be provided to you) related to the series of preferred stock being offered, as well as the complete certificate of designation that contains the terms of the applicable series of preferred stock.

*Debt Securities*. We may issue debt securities from time to time, in one or more series, as either senior or subordinated debt or as senior or subordinated convertible debt. The senior debt securities will rank equally with any other unsecured and unsubordinated debt. The subordinated debt securities will be subordinate and junior in right of payment, to the extent and in the manner described in the instrument governing the debt, to all of our senior indebtedness. Convertible or exchangeable debt securities will be convertible into or exchangeable for our common stock or our other securities. Conversion or exchange may be mandatory or optional (at our option or the holders' option) and would be at prescribed conversion or exchange rates.

Any debt securities issued under this prospectus will be issued under one or more documents called indentures, which are contracts between us and a national banking association or other eligible party, as trustee. In this prospectus, we have summarized certain general features of the debt securities under the heading "Description of Debt Securities." We urge you, however, to read the applicable prospectus supplement (and any free writing prospectus that we may authorize to be provided to you) related to the series of debt securities being offered, as well as the complete indenture and any supplemental indentures that contain the terms of the debt securities. A form of indenture has been filed as an exhibit to the registration statement of which this prospectus is a part, and supplemental indentures and forms of debt securities containing the terms of the debt securities being offered will be filed as exhibits to the registration statement of which this prospectus is a part or will be incorporated by reference from reports that we file with the SEC.

*Warrants*. We may issue warrants for the purchase of common stock, preferred stock and/or debt securities in one or more series. We may issue warrants independently or in combination with common stock, preferred stock and/or debt securities, and the warrants may be attached to or separate from these securities. In this prospectus, we have summarized certain general features of the warrants under the heading "Description of Warrants." We urge you, however, to read the applicable prospectus supplement (and any related free writing prospectus that we may authorize to be provided to you) related to the particular series of warrants being offered, as well as any warrant agreements and warrant certificates, as applicable, that contain the terms of the warrants. We have filed forms of the warrant agreements and forms of warrant certificates containing the terms of the warrants that may be offered as exhibits to the registration statement of which this prospectus is a part. We will file as exhibits to the registration statement of which this prospectus is a part, or will incorporate by reference from reports that we file with the SEC, the form of warrant and/or the warrant agreement and warrant certificate, as applicable, that contain the terms of the particular series of warrants we are offering, and any supplemental agreements, before the issuance of such warrants.

Any warrants issued under this prospectus may be evidenced by warrant certificates. Warrants also may be issued under an applicable warrant agreement that we enter into with a warrant agent. We will indicate the name and address of the warrant agent, if applicable, in the prospectus supplement relating to the particular series of warrants being offered.

*Units.* We may issue units comprised of one or more of the other securities described this prospectus in any combination. Each unit will be issued so that the holder of the unit is also the holder of each security included in the unit. Thus, the holder of a unit will have the rights and obligations of a holder of each security included in such unit. In this prospectus, we have summarized certain general features of the units. We urge you, however, to read the applicable prospectus supplement (and any free writing prospectus that we may authorize to be provided to you) related to the particular series of units being offered, as well as the complete unit agreements that contain

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the terms of the units as applicable. A form of the unit agreement, as applicable, containing the terms of the unit being offered will be filed as an exhibit to the registration statement or will be incorporated by reference from reports that we file with the SEC.

Any units may be issued under an applicable unit agreement that we enter into with a unit agent. We will indicate the name and address of the unit agent, if applicable, in the prospectus supplement relating to the particular series of units being offered.

**Use of Proceeds** 

We intend to use the net proceeds we receive from the sale of securities by us as set forth in the applicable prospectus supplement. See the section titled "Use of Proceeds" in this prospectus.

**Nasdaq Global Select Market Listing** 

Our common stock is listed on the Nasdaq Global Select Market under the symbol "ANNX." The applicable prospectus supplement will contain information, where applicable, as to other listings, if any, on the Nasdaq Global Select Market or other securities exchange of the securities covered by the applicable prospectus supplement.

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**RISK FACTORS** 

Investing in our securities involves a high degree of risk. Before deciding whether to invest in our securities, you should consider carefully the risks and uncertainties described under the section titled "Risk Factors" contained in the applicable prospectus supplement and any related free writing prospectus, and discussed under the section titled "Risk Factors" contained in our most recent Annual Report on Form 10-K and in our most recent Quarterly Report on Form 10-Q, as well as any amendments thereto reflected in subsequent filings with the SEC, which are incorporated by reference into this prospectus in their entirety, together with other information in this prospectus, the documents incorporated by reference and any free writing prospectus that we may authorize for use in connection with this offering. The risks described in these documents are not the only ones we face, but those that we consider to be material. There may be other unknown or unpredictable economic, business, competitive, regulatory or other factors that could have material adverse effects on our future results. Past financial performance may not be a reliable indicator of future performance, and historical trends should not be used to anticipate results or trends in future periods. If any of these risks actually occurs, our business, financial condition, results of operations or cash flow could be seriously harmed. This could cause the trading price of our common stock to decline, resulting in a loss of all or part of your investment. Please also read carefully the section below entitled "Special Note Regarding Forward-Looking Statements."

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**SPECIAL NOTE REGARDING FORWARD-LOOKING STATEMENTS** 

This prospectus and the documents we have filed with the SEC that are incorporated by reference herein contain "forward-looking statements" within the meaning of Section 27A of the Securities Act of 1933, as amended (the "Securities Act"), and Section 21E of the Securities Exchange Act of 1934, as amended (the "Exchange Act"). These statements relate to future events or to our future operating or financial performance and involve known and unknown risks, uncertainties and other factors that may cause our actual results, performance or achievements to be materially different from any future results, performances or achievements expressed or implied by the forward-looking statements. All statements other than statements of historical facts contained in this prospectus, including statements regarding our future results of operations and financial condition, business strategy and plans and objectives of management for future operations, are forward-looking statements. In some cases, forward-looking statements may be identified by words 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" or the negative of these terms or other similar expressions.

We have based these forward-looking statements largely on our current expectations and projections about future events and financial trends that we believe may affect our financial condition, results of operations, business strategy and financial needs. These forward-looking statements are subject to a number of known and unknown risks, uncertainties and assumptions, including risks described in the section titled "Risk Factors" and elsewhere in this prospectus and in our most recent Annual Report on Form 10-K, as well as any amendments thereto reflected in subsequent filings with the SEC, which are incorporated by reference into this prospectus in their entirety, together with other information in this prospectus, the documents incorporated by reference and any free writing prospectus that we may authorize for use in connection with a specific offering. Forward-looking statements may include, but are not limited to, statements about:

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;• our expectations regarding the potential market size and size of the potential patient populations for our
product candidates and any future product candidates, if approved for commercial use;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;• our clinical and regulatory development plans;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;• our expectations with regard to the results of our clinical studies, preclinical studies and research and
development programs, including the timing and availability of data from such studies;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;• the timing of commencement of future nonclinical studies and clinical trials and research and development
programs;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;• our ability to acquire, discover, develop and advance product candidates into, and successfully complete,
clinical trials;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;• our intentions and our ability to establish collaborations and/or partnerships;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;• the timing or likelihood of regulatory filings and approvals for our product candidates;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;• our commercialization, marketing and manufacturing capabilities and expectations;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;• our intentions with respect to the commercialization of our product candidates;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;• the pricing and reimbursement of our product candidates, if approved;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;• the implementation of our business model and strategic plans for our business and product candidates, including
additional indications for which we may pursue;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;• the scope of protection we are able to establish and maintain for intellectual property rights covering our
product candidates, including the projected terms of patent protection;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;• estimates of our expenses, future revenue, capital requirements, our needs for additional financing and our
ability to obtain additional capital;

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&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;• our intended use of proceeds from this offering and our existing cash, cash equivalents and marketable
securities;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;• the potential future sales of our common stock under our at-the-market offering program;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;• our future financial or operating performance; and

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;• developments and projections relating to our competitors and our industry, including competing products.

These risks are not exhaustive. Other sections of this prospectus may include additional factors that could harm our business and financial performance. Moreover, we operate in a very competitive and rapidly changing environment. New risks and uncertainties emerge from time to time, and it is not possible for our management to predict all risks and uncertainties, nor can we assess the impact of all such factors on our business or the extent to which any such factor, or combination of such factors, may cause actual results to differ from those contained in, or implied by, any forward-looking statements.

You should not rely upon forward-looking statements as predictions of future events. Although we believe that the expectations reflected in the forward-looking statements are reasonable, we cannot guarantee future results, levels of activity, performance or achievements. Except as required by law, we undertake no obligation to update publicly any forward-looking statements for any reason after the date of this prospectus or to conform these statements to actual results or to changes in our expectations.

In addition, statements containing the words "we believe" and similar statements reflect our beliefs and opinions on the relevant subject. These statements are based upon information available to us as of the date of this prospectus, and while we believe such information forms a reasonable basis for such statements, such information may be limited or incomplete, and our statements should not be read to indicate that we have conducted an exhaustive inquiry into, or review of, all relevant information. These statements are inherently uncertain and investors are cautioned not to unduly rely upon these statements.

You should read this prospectus, any applicable prospectus supplement, together with the documents we have filed with the SEC that are incorporated by reference herein and therein and any free writing prospectuses that we may authorize for use in connection with a specific offering completely and with the understanding that our actual future results, levels of activity, performance and achievements may be different from what we expect. We qualify all of our forward-looking statements by these cautionary statements.

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**USE OF PROCEEDS** 

Except as described in any prospectus supplement or in any related free writing prospectus that we may authorize to be provided to you in connection with a specific offering, we currently intend to use the net proceeds from the sale of securities under this prospectus for general corporate purposes, including research and development expenses, selling, general and administrative expenses and capital expenditures. As of the date of this prospectus, we cannot specify with certainty all of the particular uses of the net proceeds from the sale of securities under this prospectus. Accordingly, we will retain broad discretion over the use of such proceeds. Pending the use of the net proceeds from the sale of securities under this prospectus as described above, we intend to invest the net proceeds in short and intermediate-term, interest-bearing obligations, investment-grade instruments, certificates of deposit or direct or guaranteed obligations of the U.S. government.

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**DESCRIPTION OF CAPITAL STOCK** 

*The following summary describes our capital stock and the material provisions of our amended and restated certificate of incorporation, our amended and restated bylaws and the amended and restated investors' rights agreement to which we and certain of our stockholders are parties and the applicable provisions of the Delaware General Corporation Law (the "DGCL"). Because the following is only a summary, it does not contain all of the information that may be important to you. For a complete description, you should refer to our amended and restated certificate of incorporation, amended and restated bylaws and amended and restated investors' rights agreement, each of which has been publicly filed with the U.S. Securities and Exchange Commission (the "SEC").* 

**General** 

Our authorized capital stock consists of 300,000,000 shares of common stock, par value $0.001 per share, and 5,000,000 shares of preferred stock, par value $0.001 per share.

**Common Stock** 

*Voting Rights* 

Each holder of common stock is entitled to one vote for each share on all matters submitted to a vote of the stockholders, including the election of directors. The election of directors by our stockholders shall be determined by a plurality of the votes cast and our stockholders do not have cumulative voting rights in the election of directors. Other matters shall be generally decided by the affirmative vote of the holders of a majority of the votes cast (excluding abstentions and broker non-votes) on such matter. In addition, the affirmative vote of holders of 66 2/3% of the voting power of all of the then outstanding voting stock will be required to take certain actions, including amending certain provisions of our amended and restated certificate of incorporation, including the provisions relating to amending our amended and restated bylaws, the classified board and director liability.

*Dividends* 

Subject to preferences that may be applicable to any then-outstanding preferred stock, holders of our common stock are entitled to receive dividends as may be declared from time to time by our board of directors out of legally available funds.

*Liquidation* 

In the event of our liquidation, dissolution, or winding up, holders of our common stock will be entitled to share ratably in the net assets legally available for distribution to stockholders after the payment of all of our debts and other liabilities, subject to the satisfaction of any liquidation preference granted to the holders of any then outstanding shares of preferred stock.

*Rights and Preferences* 

Holders of our common stock have no preemptive, conversion or subscription rights, and there are no redemption or sinking fund provisions applicable to our common stock. The rights, preferences, and privileges of the holders of our common stock are subject to, and may be adversely affected by, the rights of the holders of shares of any series of our preferred stock that we may designate and issue in the future.

***Fully Paid and Nonassessable***

All of our outstanding shares of common stock are fully paid and nonassessable.

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**Preferred Stock** 

Our board of directors has the authority, without further action by our stockholders, to issue up to 5,000,000 shares of preferred stock in one or more series and to fix the rights, preferences, privileges and restrictions thereof. These rights, preferences and privileges could include dividend rights, conversion rights, voting rights, terms of redemption, liquidation preferences, sinking fund terms and the number of shares constituting, or the designation of such series, any or all of which may be greater than the rights of our common stock. The issuance of our preferred stock could adversely affect the voting power of holders of common stock and the likelihood that such holders will receive dividend payments and payments upon our liquidation. In addition, the issuance of preferred stock could have the effect of delaying, deferring or preventing a change in control of our company or other corporate action.

**Registration Rights** 

Under our amended and restated investors' rights agreement, certain holders of shares of our common stock, or their transferees, have the right to require us to register their shares under the Securities Act of 1933, as amended (the "Securities Act"), so that those shares may be publicly resold, and certain holders of shares of our common stock, or their transferees, have the right to include their shares in any registration statement we file, in each case as described below.

*Demand Registration Rights* 

Certain holders of shares of our common stock are entitled to certain demand registration rights. The holders of at least 60% of such registrable securities may, on not more than two occasions, request that we register all or a portion of their shares, subject to certain specified exceptions.

*Piggyback Registration Rights* 

In the event that we propose to register any of our securities under the Securities Act, either for our own account or for the account of other security holders, certain holders of registrable securities will be entitled to certain "piggyback" registration rights allowing them to include their shares in such registration, subject to specified conditions and limitations.

*S-3 Registration Rights* 

Certain holders of shares of our common stock are entitled to certain Form S-3 registration rights. The holders of at least 30% of such registrable securities may, on not more than two registrations on Form S-3 within any 12-month period, request that we register all or a portion of their shares on Form S-3 if we are qualified to file a registration statement on Form S-3, subject to specified exceptions. Such request for registration on Form S-3 must cover securities with an aggregate offering price which equals or exceeds $1.0 million, net of selling expenses. The right to have such shares registered on Form S-3 is further subject to other specified conditions and limitations.

*Resale Registration Rights* 

On July 7, 2022, in connection with a private placement of our securities, we entered into a securities purchase agreement with certain holders of our common stock, warrants and pre-funded warrants. Pursuant to the terms of this securities purchase agreement, we have agreed to use commercially reasonable efforts to file a registration statement with the SEC by no later than November 8, 2022 to register for resale under the Securities Act all of the shares of our common stock issued and shares of our common stock issuable upon exercise of the pre-funded warrants and the common warrants issued to certain investors. On November 4, 2022, we filed a Registration Statement on Form S-3 in connection with the registrable securities issued in this private placement

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**Anti-Takeover Effects of Provisions of Delaware Law and Our Amended and Restated Certificate of Incorporation and Amended and Restated Bylaws** 

Certain provisions of Delaware law and our amended and restated certificate of incorporation and our amended and restated bylaws contain provisions that could make the following transactions more difficult: acquisition of us by means of a tender offer; acquisition of us by means of a proxy contest or otherwise; or removal of our incumbent officers and directors. It is possible that these provisions could make it more difficult to accomplish or could deter transactions that stockholders may otherwise consider to be in their best interest or in our best interests, including transactions that might result in a premium over the market price for our shares.

These provisions, summarized below, are expected to discourage coercive takeover practices and inadequate takeover bids. These provisions are also designed to encourage persons seeking to acquire control of us to first negotiate with our board of directors. We believe that the benefits of increased protection of our potential ability to negotiate with the proponent of an unfriendly or unsolicited proposal to acquire or restructure us outweigh the disadvantages of discouraging these proposals because negotiation of these proposals could result in an improvement of their terms.

***Delaware Anti-Takeover Statute***

We are subject to Section 203 of the DGCL, which prohibits persons deemed "interested stockholders" from engaging in a "business combination" with a publicly-held Delaware corporation for three years following the date these persons become interested stockholders unless the business combination is, or the transaction in which the person became an interested stockholder was, approved in a prescribed manner or another prescribed exception applies. Generally, an "interested stockholder" is a person who, together with affiliates and associates, owns, or within three years prior to the determination of interested stockholder status did own, 15% or more of a corporation's voting stock. Generally, a "business combination" includes a merger, asset or stock sale, or other transaction resulting in a financial benefit to the interested stockholder. The existence of this provision may have an anti-takeover effect with respect to transactions not approved in advance by the board of directors, such as discouraging takeover attempts that might result in a premium over the market price of our common stock.

*Undesignated Preferred Stock* 

The ability to authorize undesignated preferred stock makes it possible for our board of directors to issue preferred stock with voting or other rights or preferences that could impede the success of any attempt to effect a change in control of our company. These and other provisions may have the effect of deterring hostile takeovers or delaying changes in control or management of our company.

*Special Stockholder Meetings* 

Our amended and restated certificate of incorporation provide that a special meeting of stockholders may be called at any time by our board of directors, but such special meetings may not be called by the stockholders or any other person or persons.

*Requirements for Advance Notification of Stockholder Nominations and Proposals* 

Our amended and restated bylaws establish advance notice procedures with respect to stockholder proposals and the nomination of candidates for election as directors, other than nominations made by or at the direction of the board of directors or a committee of the board of directors.

*Stockholder Action by Written Consent* 

Our amended and restated certificate of incorporation precludes stockholder action by written consent without a meeting.

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*Classified Board; Election and Removal of Directors; Filling Vacancies* 

Our board of directors is divided into three classes, divided as nearly as equal in number as possible. The directors in each class serve for a three-year term, one class being elected each year by our stockholders, with staggered three-year terms. Only one class of directors will be elected at each annual meeting of our stockholders, with the other classes continuing for the remainder of their respective three-year terms. Because our stockholders do not have cumulative voting rights, our stockholders holding a majority of the shares of common stock outstanding will be able to elect all of our directors. Our amended and restated certificate of incorporation provides for the removal of any of our directors only for cause and requires a stockholder vote by the holders of at least a 66 2/3% of the voting power of the then outstanding voting stock. Furthermore, any vacancy on our board of directors, however occurring, including a vacancy resulting from an increase in the size of the board, may only be filled by a resolution of the board of directors unless the board of directors determines that such vacancies shall be filled by the stockholders. This system of electing and removing directors and filling vacancies may tend to discourage a third party from making a tender offer or otherwise attempting to obtain control of us because it generally makes it more difficult for stockholders to replace a majority of the directors.

*Choice of Forum* 

If any action the subject matter of which is within the scope described above is filed in a court other than a court located within the State of Delaware, or a Foreign Action, in the name of any stockholder, such stockholder shall be deemed to have consented to the personal jurisdiction of the state and federal courts located within the State of Delaware in connection with any action brought in any such court to enforce the applicable provisions of our amended and restated certificate of incorporation and amended and restated bylaws and having service of process made upon such stockholder in any such action by service upon such stockholder's counsel in the Foreign Action as agent for such stockholder. Although our amended and restated certificate of incorporation and amended and restated bylaws will contain the choice of forum provision described above, it is possible that a court could find that such a provision is inapplicable for a particular claim or action or that such provision is unenforceable.

This choice of forum provision may limit a stockholder's ability to bring a claim in a judicial forum that it finds favorable for disputes with us or any of our directors, officers, other employees or stockholders, which may

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discourage lawsuits with respect to such claims, although our stockholders will not be deemed to have waived our compliance with federal securities laws and the rules and regulations thereunder.

*Amendment of Charter Provisions* 

The amendment of any of the above provisions in our amended and restated certificate of incorporation, except for the provision making it possible for our board of directors to issue undesignated preferred stock, requires approval by a stockholder vote by the holders of at least a 66 2/3% of the voting power of the then outstanding voting stock.

The provisions of the Delaware General Corporation Law our amended and restated certificate of incorporation and our amended and restated bylaws could have the effect of discouraging others from attempting hostile takeovers and, as a consequence, they may also inhibit temporary fluctuations in the market price of our common stock that often result from actual or rumored hostile takeover attempts. These provisions may also have the effect of preventing changes in our management. It is possible that these provisions could make it more difficult to accomplish transactions that stockholders may otherwise deem to be in their best interests.

**Limitation on Liability and Indemnification** 

Our amended and restated certificate of incorporation and our amended and restated bylaws limit our directors' liability, contain provisions that provide that we may indemnify our directors and officers to the fullest extent permitted under the DGCL. The DGCL provides that directors of a corporation will not be personally liable for monetary damages for breach of their fiduciary duties as directors, except for liability for any:

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;• transaction from which the director derives an improper personal benefit;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;• act or omission not in good faith or that involves intentional misconduct or a knowing violation of law;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;• unlawful payment of dividends or redemption of shares; or

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;• breach of a director's duty of loyalty to the corporation or its stockholders.

These limitations of liability do not apply to liabilities arising under federal securities laws and do not affect the availability of equitable remedies such as injunctive relief or recession.

The DGCL and our amended and restated bylaws provide that we will, in certain situations, indemnify our directors and officers and may indemnify other employees and other agents, to the fullest extent permitted by law. Any indemnified person is also entitled, subject to certain limitations, to advancement, direct payment or reimbursement of reasonable expenses (including attorneys' fees and disbursements) in advance of the final disposition of the proceeding.

In addition, we have entered, and intend to continue to enter, into separate indemnification agreements with our directors and officers. These indemnification agreements, among other things, require us to indemnify our directors and officers for certain expenses, including attorneys' fees, judgments, fines and settlement amounts incurred by a director or officer in any action or proceeding arising out of their services as a director or officer, or any other company or enterprise to which the person provides services at our request.

We also maintain a directors' and officers' insurance policy pursuant to which our directors and officers are insured against liability for actions taken in their capacities as directors and officers.

We believe that these provisions in our amended and restated certificate of incorporation and amended and restated bylaws and these indemnification agreements are necessary to attract and retain qualified persons as directors and officers.

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Insofar as indemnification for liabilities arising under the Securities Act may be permitted to directors, officers or control persons, in the opinion of the SEC, such indemnification is against public policy, as expressed in the Securities Act and is therefore unenforceable.

**Transfer Agent and Registrar** 

The transfer agent and registrar for our common stock is Computershare Trust Company, N.A. The transfer agent and registrar's address is 150 Royall Street, Canton, Massachusetts 02021.

**Listing on the Nasdaq Global Select Market** 

Our common stock is listed on the Nasdaq Global Select Market under the symbol "ANNX." The applicable prospectus supplement will contain information, where applicable, as to any other listing, if any, on the Nasdaq Global Select Market or any securities market or other exchange of the preferred stock covered by such prospectus supplement.

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**DESCRIPTION OF DEBT SECURITIES** 

We may issue debt securities from time to time, in one or more series, as either senior or subordinated debt or as senior or subordinated convertible debt. While the terms we have summarized below will apply generally to any debt securities that we may offer under this prospectus, we will describe the particular terms of any debt securities that we may offer in more detail in the applicable prospectus supplement. The terms of any debt securities offered under a prospectus supplement may differ from the terms described below.

We will issue the debt securities under either the senior indenture or the subordinated indenture that we will enter into with trustee named in the applicable indenture. If we offer senior debt securities, we will issue them under the senior indenture. If we issue subordinated debt securities, we will issue them under the subordinated indenture. We have filed the forms of indentures as an exhibit to the registration statement of which this prospectus is a part, and supplemental indentures and forms of debt securities containing the terms of the debt securities being offered will be filed as exhibits to the registration statement of which this prospectus is a part or will be incorporated by reference from reports that we file with the SEC. The indentures will be qualified under the Trust Indenture Act of 1939, as amended, or the Trust Indenture Act. Unless the context requires otherwise, whenever we refer to the indenture, we are referring to the senior indenture or the subordinated indenture, as applicable, and we also are referring to any supplemental indentures that specify the terms of a particular series of debt securities.

The following summary of material provisions of the debt securities and the indentures is subject to, and qualified in its entirety by reference to, all of the provisions of the indenture applicable to a particular series of debt securities. We urge you to read the applicable prospectus supplements and any related free writing prospectuses related to the debt securities that we may offer under this prospectus, as well as the complete indenture that contains the terms of the debt securities.

**General** 

The indenture does not limit the amount of debt securities that we may issue. It provides that we may issue debt securities up to the principal amount that we may authorize and may be in any currency or currency unit that we may designate. Except for the limitations on consolidation, merger and sale of all or substantially all of our assets contained in the indenture, the terms of the indenture do not contain any covenants or other provisions designed to give holders of any debt securities protection against changes in our operations, financial condition or transactions involving us.

We may issue the debt securities issued under the indenture as "discount securities," which means they may be sold at a discount below their stated principal amount. These debt securities, as well as other debt securities that are not issued at a discount, may be issued with "original issue discount," or OID, for U.S. federal income tax purposes because of interest payment and other characteristics or terms of the debt securities. Material U.S. federal income tax considerations applicable to debt securities issued with OID will be described in more detail in any applicable prospectus supplement.

We will describe in the applicable prospectus supplement the terms of the series of debt securities being offered, including:

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;• the title of the series of debt securities;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;• any limit upon the aggregate principal amount that may be issued;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;• the maturity date or dates;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;• the form of the debt securities of the series;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;• the applicability of any guarantees;

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&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;• whether or not the debt securities will be secured or unsecured, and the terms of any secured debt;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;• whether the debt securities rank as senior debt, senior subordinated debt, subordinated debt or any combination
thereof, and the terms of any subordination;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;• if the price (expressed as a percentage of the aggregate principal amount thereof) at which such debt securities
will be issued is a price other than the principal amount thereof, the portion of the principal amount thereof payable upon declaration of acceleration of the maturity thereof, or if applicable, the portion of the principal amount of such debt
securities that is convertible into another security or the method by which any such portion shall be determined;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;• the interest rate or rates, which may be fixed or variable, or the method for determining the rate and the date
interest will begin to accrue, the dates interest will be payable and the regular record dates for interest payment dates or the method for determining such dates;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;• our right, if any, to defer payment of interest and the maximum length of any such deferral period;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;• if applicable, the date or dates after which, or the period or periods during which, and the price or prices at
which, we may, at our option, redeem the series of debt securities pursuant to any optional or provisional redemption provisions and the terms of those redemption provisions;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;• the date or dates, if any, on which, and the price or prices at which we are obligated, pursuant to any mandatory
sinking fund or analogous fund provisions or otherwise, to redeem, or at the holder's option to purchase, the series of debt securities and the currency or currency unit in which the debt securities are payable;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;• the denominations in which we will issue the series of debt securities, if other than denominations of $1,000 and
any integral multiple thereof;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;• any and all terms, if applicable, relating to any auction or remarketing of the debt securities of that series
and any security for our obligations with respect to such debt securities and any other terms which may be advisable in connection with the marketing of debt securities of that series;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;• whether the debt securities of the series shall be issued in whole or in part in the form of a global security or
securities; the terms and conditions, if any, upon which such global security or securities may be exchanged in whole or in part for other individual securities; and the depositary for such global security or securities;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;• if applicable, the provisions relating to conversion or exchange of any debt securities of the series and the
terms and conditions upon which such debt securities will be so convertible or exchangeable, including the conversion or exchange price, as applicable, or how it will be calculated and may be adjusted, any mandatory or optional (at our option or the
holders' option) conversion or exchange features, the applicable conversion or exchange period and the manner of settlement for any conversion or exchange;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;• if other than the full principal amount thereof, the portion of the principal amount of debt securities of the
series which shall be payable upon declaration of acceleration of the maturity thereof;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;• additions to or changes in the covenants applicable to the particular debt securities being issued, including,
among others, the consolidation, merger or sale covenant;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;• additions to or changes in the Events of Default with respect to the securities and any change in the right of
the trustee or the holders to declare the principal, premium, if any, and interest, if any, with respect to such securities to be due and payable;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;• additions to or changes in or deletions of the provisions relating to covenant defeasance and legal defeasance;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;• additions to or changes in the provisions relating to satisfaction and discharge of the indenture;

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&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;• additions to or changes in the provisions relating to the modification of the indenture both with and without the
consent of holders of debt securities issued under the indenture;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;• the currency of payment of debt securities if other than U.S. dollars and the manner of determining the
equivalent amount in U.S. dollars;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;• whether interest will be payable in cash or additional debt securities at our or the holders' option and
the terms and conditions upon which the election may be made;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;• the terms and conditions, if any, upon which we will pay amounts in addition to the stated interest, premium, if
any and principal amounts of the debt securities of the series to any holder that is not a "United States person" for federal tax purposes;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;• any restrictions on transfer, sale or assignment of the debt securities of the series; and

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;• any other specific terms, preferences, rights or limitations of, or restrictions on, the debt securities, any
other additions or changes in the provisions of the indenture, and any terms that may be required by us or advisable under applicable laws or regulations.

**Conversion or Exchange Rights** 

We will set forth in the applicable prospectus supplement the terms on which a series of debt securities may be convertible into or exchangeable for our common stock or our other securities. We will include provisions as to settlement upon conversion or exchange and whether conversion or exchange is mandatory, at the option of the holder or at our option. We may include provisions pursuant to which the number of shares of our common stock or our other securities that the holders of the series of debt securities receive would be subject to adjustment.

**Consolidation, Merger or Sale** 

Unless we provide otherwise in the prospectus supplement applicable to a particular series of debt securities, the indenture will not contain any covenant that restricts our ability to merge or consolidate, or sell, convey, transfer or otherwise dispose of our assets as an entirety or substantially as an entirety. However, any successor to or acquirer of such assets (other than a subsidiary of ours) must assume all of our obligations under the indenture or the debt securities, as appropriate.

**Events of Default under the Indenture** 

Unless we provide otherwise in the prospectus supplement applicable to a particular series of debt securities, the following are events of default under the indenture with respect to any series of debt securities that we may issue:

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;• if we fail to pay any installment of interest on any series of debt securities, as and when the same shall become
due and payable, and such default continues for a period of 90 days; provided, however, that a valid extension of an interest payment period by us in accordance with the terms of any indenture supplemental thereto shall not constitute a default in
the payment of interest for this purpose;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;• if we fail to pay the principal of, or premium, if any, on any series of debt securities as and when the same
shall become due and payable whether at maturity, upon redemption, by declaration or otherwise, or in any payment required by any sinking or analogous fund established with respect to such series; provided, however, that a valid extension of the
maturity of such debt securities in accordance with the terms of any indenture supplemental thereto shall not constitute a default in the payment of principal or premium, if any;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;• if we fail to observe or perform any other covenant or agreement contained in the debt securities or the
indenture, other than a covenant specifically relating to another series of debt securities, and our failure

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continues for 90 days after we receive written notice of such failure, requiring the same to be remedied and stating that such is a notice of default thereunder, from the trustee or holders of at least 25% in aggregate principal amount of the outstanding debt securities of the applicable series; and <br>

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;• if specified events of bankruptcy, insolvency or reorganization occur.

If an event of default with respect to debt securities of any series occurs and is continuing, other than an event of default specified in the last bullet point above, the trustee or the holders of at least 25% in aggregate principal amount of the outstanding debt securities of that series, by notice to us in writing, and to the trustee if notice is given by such holders, may declare the unpaid principal of, premium, if any, and accrued interest, if any, due and payable immediately. If an event of default specified in the last bullet point above occurs with respect to us, the principal amount of and accrued interest, if any, of each issue of debt securities then outstanding shall be due and payable without any notice or other action on the part of the trustee or any holder.

The holders of a majority in principal amount of the outstanding debt securities of an affected series may waive any default or event of default with respect to the series and its consequences, except defaults or events of default regarding payment of principal, premium, if any, or interest, unless we have cured the default or event of default in accordance with the indenture. Any waiver shall cure the default or event of default.

Subject to the terms of the indenture, if an event of default under an indenture shall occur and be continuing, the trustee will be under no obligation to exercise any of its rights or powers under such indenture at the request or direction of any of the holders of the applicable series of debt securities, unless such holders have offered the trustee reasonable indemnity. The holders of a majority in principal amount of the outstanding debt securities of any series will have the right to direct the time, method and place of conducting any proceeding for any remedy available to the trustee, or exercising any trust or power conferred on the trustee, with respect to the debt securities of that series, provided that:

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;• the direction so given by the holder is not in conflict with any law or the applicable indenture; and

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;• subject to its duties under the Trust Indenture Act, the trustee need not take any action that might involve it
in personal liability or might be unduly prejudicial to the holders not involved in the proceeding.

A holder of the debt securities of any series will have the right to institute a proceeding under the indenture or to appoint a receiver or trustee, or to seek other remedies only if:

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;• the holder has given written notice to the trustee of a continuing event of default with respect to that series;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;• the holders of at least 25% in aggregate principal amount of the outstanding debt securities of that series have
made written request,

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;• such holders have offered to the trustee indemnity satisfactory to it against the costs, expenses and liabilities
to be incurred by the trustee in compliance with the request; and

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;• the trustee does not institute the proceeding, and does not receive from the holders of a majority in aggregate
principal amount of the outstanding debt securities of that series other conflicting directions within 90 days after the notice, request and offer.

These limitations do not apply to a suit instituted by a holder of debt securities if we default in the payment of the principal, premium, if any, or interest on, the debt securities.

We will periodically file statements with the trustee regarding our compliance with specified covenants in the indenture.

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**Modification of Indenture; Waiver** 

We and the trustee may change an indenture without the consent of any holders with respect to specific matters:

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;• to cure any ambiguity, defect or inconsistency in the indenture or in the debt securities of any series;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;• to comply with the provisions described above under "Description of Debt Securities—Consolidation,
Merger or Sale;"

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;• to provide for uncertificated debt securities in addition to or in place of certificated debt securities;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;• to add to our covenants, restrictions, conditions or provisions such new covenants, restrictions, conditions or
provisions for the benefit of the holders of all or any series of debt securities, to make the occurrence, or the occurrence and the continuance, of a default in any such additional covenants, restrictions, conditions or provisions an event of
default or to surrender any right or power conferred upon us in the indenture;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;• to add to, delete from or revise the conditions, limitations, and restrictions on the authorized amount, terms,
or purposes of issue, authentication and delivery of debt securities, as set forth in the indenture;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;• to make any change that does not adversely affect the interests of any holder of debt securities of any series in
any material respect;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;• to provide for the issuance of and establish the form and terms and conditions of the debt securities of any
series as provided above under "Description of Debt Securities—General" to establish the form of any certifications required to be furnished pursuant to the terms of the indenture or any series of debt securities, or to add to the
rights of the holders of any series of debt securities;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;• to evidence and provide for the acceptance of appointment under any indenture by a successor trustee; or

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;• to comply with any requirements of the SEC in connection with the qualification of any indenture under the Trust
Indenture Act.

In addition, under the indenture, the rights of holders of a series of debt securities may be changed by us and the trustee with the written consent of the holders of at least a majority in aggregate principal amount of the outstanding debt securities of each series that is affected. However, unless we provide otherwise in the prospectus supplement applicable to a particular series of debt securities, we and the trustee may make the following changes only with the consent of each holder of any outstanding debt securities affected:

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;• extending the fixed maturity of any debt securities of any series;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;• reducing the principal amount, reducing the rate of or extending the time of payment of interest, or reducing any
premium payable upon the redemption of any series of any debt securities; or

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;• reducing the percentage of debt securities, the holders of which are required to consent to any amendment,
supplement, modification or waiver.

**Discharge** 

Each indenture provides that we can elect to be discharged from our obligations with respect to one or more series of debt securities, except for specified obligations, including obligations to:

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;• provide for payment;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;• register the transfer or exchange of debt securities of the series;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;• replace stolen, lost or mutilated debt securities of the series;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;• pay principal of and premium and interest on any debt securities of the series;

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&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;• maintain paying agencies;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;• hold monies for payment in trust;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;• recover excess money held by the trustee;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;• compensate and indemnify the trustee; and

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;• appoint any successor trustee.

In order to exercise our rights to be discharged, we must deposit with the trustee money or government obligations sufficient to pay all the principal of, any premium, if any, and interest on, the debt securities of the series on the dates payments are due.

**Form, Exchange and Transfer** 

We will issue the debt securities of each series only in fully registered form without coupons and, unless we provide otherwise in the applicable prospectus supplement, in denominations of $1,000 and any integral multiple thereof. The indenture provides that we may issue debt securities of a series in temporary or permanent global form and as book-entry securities that will be deposited with, or on behalf of, The Depository Trust Company, or DTC, or another depositary named by us and identified in the applicable prospectus supplement with respect to that series. To the extent the debt securities of a series are issued in global form and as book-entry, a description of terms relating to any book-entry securities will be set forth in the applicable prospectus supplement.

At the option of the holder, subject to the terms of the indenture and the limitations applicable to global securities described in the applicable prospectus supplement, the holder of the debt securities of any series can exchange the debt securities for other debt securities of the same series, in any authorized denomination and of like tenor and aggregate principal amount.

Subject to the terms of the indenture and the limitations applicable to global securities set forth in the applicable prospectus supplement, holders of the debt securities may present the debt securities for exchange or for registration of transfer, duly endorsed or with the form of transfer endorsed thereon duly executed if so required by us or the security registrar, at the office of the security registrar or at the office of any transfer agent designated by us for this purpose. Unless otherwise provided in the debt securities that the holder presents for transfer or exchange, we will impose no service charge for any registration of transfer or exchange, but we may require payment of any taxes or other governmental charges.

We will name in the applicable prospectus supplement the security registrar, and any transfer agent in addition to the security registrar, that we initially designate for any debt securities. We may at any time designate additional transfer agents or rescind the designation of any transfer agent or approve a change in the office through which any transfer agent acts, except that we will be required to maintain a transfer agent in each place of payment for the debt securities of each series.

If we elect to redeem the debt securities of any series, we will not be required to:

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;• issue, register the transfer of, or exchange any debt securities of that series during a period beginning at the
opening of business 15 days before the day of mailing of a notice of redemption of any debt securities that may be selected for redemption and ending at the close of business on the day of the mailing; or

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;• register the transfer of or exchange any debt securities so selected for redemption, in whole or in part, except
the unredeemed portion of any debt securities we are redeeming in part.

**Information Concerning the Trustee** 

The trustee, other than during the occurrence and continuance of an event of default under an indenture, undertakes to perform only those duties as are specifically set forth in the applicable indenture. Upon an event of

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default under an indenture, the trustee must use the same degree of care as a prudent person would exercise or use in the conduct of his or her own affairs. Subject to this provision, the trustee is under no obligation to exercise any of the powers given it by the indenture at the request of any holder of debt securities unless it is offered reasonable security and indemnity against the costs, expenses and liabilities that it might incur.

**Payment and Paying Agents** 

Unless we otherwise indicate in the applicable prospectus supplement, we will make payment of the interest on any debt securities on any interest payment date to the person in whose name the debt securities, or one or more predecessor securities, are registered at the close of business on the regular record date for the interest.

We will pay principal of and any premium and interest on the debt securities of a particular series at the office of the paying agents designated by us, except that unless we otherwise indicate in the applicable prospectus supplement, we will make interest payments by check that we will mail to the holder or by wire transfer to certain holders. Unless we otherwise indicate in the applicable prospectus supplement, we will designate the corporate trust office of the trustee as our sole paying agent for payments with respect to debt securities of each series. We will name in the applicable prospectus supplement any other paying agents that we initially designate for the debt securities of a particular series. We will maintain a paying agent in each place of payment for the debt securities of a particular series.

All money we pay to a paying agent or the trustee for the payment of the principal of or any premium or interest on any debt securities that remains unclaimed at the end of two years after such principal, premium or interest has become due and payable will be repaid to us, and the holder of the debt security thereafter may look only to us for payment thereof.

**Governing Law** 

The indenture and the debt securities will be governed by and construed in accordance with the internal laws of the State of New York, except to the extent that the Trust Indenture Act of 1939 is applicable.

**Provisions Relating only to the Subordinated Debt Securities** 

The subordinated debt securities will be subordinate and junior in priority of payment to certain of our other indebtedness to the extent described in a prospectus supplement. The indentures in the forms initially filed as exhibits to the registration statement of which this prospectus is a part do not limit the amount of indebtedness which we may incur, including senior indebtedness or subordinated indebtedness, and do not limit us from issuing any other debt, including secured debt or unsecured debt.

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**DESCRIPTION OF WARRANTS** 

The following description, together with the additional information we may include in any applicable prospectus supplements and in any related free writing prospectuses that we may authorize to be distributed to you, summarizes the material terms and provisions of the warrants that we may offer under this prospectus, which may consist of warrants to purchase common stock, preferred stock or debt securities and may be issued in one or more series. Warrants may be offered independently or in combination with common stock, preferred stock or debt securities offered by any prospectus supplement and may be attached to or separate from those securities. While the terms we have summarized below will apply generally to any warrants that we may offer under this prospectus, we will describe the particular terms of any series of warrants in more detail in the applicable prospectus supplement and any applicable free writing prospectus. The following description of warrants will apply to the warrants offered by this prospectus unless we provide otherwise in the applicable prospectus supplement. The applicable prospectus supplement for a particular series of warrants may specify different or additional terms.

We have filed forms of the warrant agreements and forms of warrant certificates containing the terms of the warrants that may be offered as exhibits to the registration statement of which this prospectus is a part. We will file as exhibits to the registration statement of which this prospectus is a part, or will incorporate by reference from reports that we file with the SEC, the form of warrant and/or the warrant agreement and warrant certificate, as applicable, that describe the terms of the particular series of warrants we are offering, and any supplemental agreements, before the issuance of such warrants. The following summaries of material terms and provisions of the warrants are subject to, and qualified in their entirety by reference to, all the provisions of the form of warrant and/or the warrant agreement and warrant certificate, as applicable, and any supplemental agreements applicable to a particular series of warrants that we may offer under this prospectus. We urge you to read the applicable prospectus supplement related to the particular series of warrants that we may offer under this prospectus, as well as any related free writing prospectus, and the complete form of warrant and/or the warrant agreement and warrant certificate, as applicable, and any supplemental agreements, that contain the terms of the warrants.

**General** 

We will describe in the applicable prospectus supplement the terms of the series of warrants being offered, including:

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;• the title of such securities;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;• the offering price and aggregate number of warrants offered;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;• the currency for which the warrants may be purchased;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;• if applicable, the designation and terms of the securities with which the warrants are issued and the number of
warrants issued with each such security or each principal amount of such security;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;• if applicable, the date on and after which the warrants and the related securities will be separately
transferable;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;• if applicable, the minimum or maximum amount of such warrants which may be exercised at any one time;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;• in the case of warrants to purchase debt securities, the principal amount of debt securities purchasable upon
exercise of one warrant and the price at which, and currency in which, this principal amount of debt securities may be purchased upon such exercise;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;• in the case of warrants to purchase common stock or preferred stock, the number of shares of common stock or
preferred stock, as the case may be, purchasable upon the exercise of one warrant and the price at which, and the currency in which, these shares may be purchased upon such exercise;

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&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;• in the case of warrants to purchase debt securities, the principal amount of debt securities purchasable upon
exercise of one warrant and the price at which, and currency in which, this principal amount of debt securities may be purchased upon such exercise;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;• the effect of any merger, consolidation, sale or other disposition of our business on the warrant agreements and
the warrants;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;• the terms of any rights to redeem or call the warrants;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;• the terms of any rights to force the exercise of the warrants;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;• any provisions for changes to or adjustments in the exercise price or number of securities issuable upon exercise
of the warrants;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;• the dates on which the right to exercise the warrants will commence and expire;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;• the manner in which the warrant agreements and warrants may be modified;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;• a discussion of any material or special U.S. federal income tax considerations of holding or exercising the
warrants;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;• the terms of the securities issuable upon exercise of the warrants; and

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;• any other specific terms, preferences, rights or limitations of or restrictions on the warrants.

Before exercising their warrants, holders of warrants will not have any of the rights of holders of the securities purchasable upon such exercise, including:

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;• in the case of warrants to purchase debt securities, the right to receive payments of principal of, or premium,
if any, or interest on, the debt securities purchasable upon exercise or to enforce covenants in the applicable indenture; or

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;• in the case of warrants to purchase common stock or preferred stock, the right to receive dividends, if any, or,
payments upon our liquidation, dissolution or winding up or to exercise voting rights, if any.

**Exercise of Warrants** 

Each warrant will entitle the holder to purchase the securities that we specify in the applicable prospectus supplement at the exercise price that we describe in the applicable prospectus supplement. The warrants may be exercised as set forth in the prospectus supplement relating to the warrants offered. Unless we otherwise specify in the applicable prospectus supplement, warrants may be exercised at any time up to the close of business on the expiration date set forth in the prospectus supplement relating to the warrants offered thereby. After the close of business on the expiration date, unexercised warrants will become void.

Unless we otherwise specify in the applicable prospectus supplement, holders of the warrants may exercise the warrants by delivering the warrant certificate representing the warrants to be exercised together with specified information, and paying the required amount to the warrant agent in immediately available funds, as provided in the applicable prospectus supplement. We will set forth on the reverse side of the warrant certificate and in the applicable prospectus supplement the information that the holder of the warrant will be required to deliver to the warrant agent in connection with the exercise of the warrant.

Upon receipt of payment and the warrant or warrant certificate, as applicable, properly completed and duly executed at the corporate trust office of the warrant agent, if any, or any other office, including ours, indicated in the applicable prospectus supplement, we will, as soon as practicable, issue and deliver the securities purchasable upon such exercise. If fewer than all of the warrants (or the warrants represented by such warrant certificate) are exercised, a new warrant or a new warrant certificate, as applicable, will be issued for the remaining warrants. If we so indicate in the applicable prospectus supplement, holders of the warrants may surrender securities as all or part of the exercise price for warrants.

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**Governing Law** 

Unless we otherwise specify in the applicable prospectus supplement, the warrants and any warrant agreements and any claim, controversy or dispute arising under or related to the warrants or warrant agreements, will be governed by and construed in accordance with the laws of the State of New York.

**Enforceability of Rights by Holders of Warrants** 

Each warrant agent, if any, will act solely as our agent under the applicable warrant agreement and will not assume any obligation or relationship of agency or trust with any holder of any warrant. A single bank or trust company may act as warrant agent for more than one issue of warrants. A warrant agent will have no duty or responsibility in case of any default by us under the applicable warrant agreement or warrant, including any duty or responsibility to initiate any proceedings at law or otherwise, or to make any demand upon us. Any holder of a warrant may, without the consent of the related warrant agent or the holder of any other warrant, enforce by appropriate legal action its right to exercise, and receive the securities purchasable upon exercise of, its warrants.

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**DESCRIPTION OF UNITS** 

We may issue units consisting of any combination of the other types of securities offered under this prospectus in one or more series. We may evidence each series of units by unit certificates that we will issue under a separate agreement. We may enter into unit agreements with a unit agent. Each unit agent will be a bank or trust company that we select. We will indicate the name and address of the unit agent in the applicable prospectus supplement relating to a particular series of units.

The following description, together with the additional information included in any applicable prospectus supplement, summarizes the general features of the units that we may offer under this prospectus. While the terms summarized below will apply generally to any units we may offer, we will describe the particular terms of any series of units in more detail in the applicable prospectus supplement. You should read any prospectus supplement and any free writing prospectus that we may authorize to be provided to you related to the series of units being offered, as well as the complete unit agreements that contain the terms of the units. Specific unit agreements will contain additional important terms and provisions and we will file as an exhibit to the registration statement of which this prospectus is a part, or will incorporate by reference from another report that we file with the SEC, the form of each unit agreement relating to units offered under this prospectus.

Each unit will be issued so that the holder of the unit is also the holder of each security included in the unit. Thus, the holder of a unit will have the rights and obligations of a holder of each included security. The unit agreement under which a unit is issued may provide that the securities included in the unit may not be held or transferred separately at any time, or at any time before a specified date.

If we offer any units, certain terms of that series of units will be described in the applicable prospectus supplement, including, without limitation, the following, as applicable:

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;• the designation and the terms of the units and of the securities constituting the units, including whether and
under what circumstances the securities comprising the units may be traded separately;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;• the identity of any unit agent for the units, if applicable, and of any other depositaries, execution or paying
agents, transfer agents, registrars or other agents;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;• any additional terms of the governing unit agreement, if applicable;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;• any additional provisions for the issuance, payment, settlement, transfer or exchange of the units or of the debt
securities, common stock, preferred stock or warrants constituting the unit; and

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;• any applicable U.S. federal income tax considerations.

The provisions described in this section, as well as those described under "Description of Capital Stock," "Description of Debt Securities" and "Description of Warrants" will apply to each unit and to any common stock, preferred stock, debt security or warrant included in each unit, respectively.

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**LEGAL OWNERSHIP OF SECURITIES** 

We can issue securities in registered form or in the form of one or more global securities. We describe global securities in greater detail below. We refer to those persons who have securities registered in their own names on the books that we or any applicable trustee, depositary or warrant or unit agent, maintain for this purpose as the "holders" of those securities. These persons are the legal holders of the securities. We refer to those persons who, indirectly through others, own beneficial interests in securities that are not registered in their own names, as "indirect holders" of those securities. As we discuss below, indirect holders are not legal holders, and investors in securities issued in book-entry form or in street name will be indirect holders.

**Book-Entry Holders** 

We may issue securities in book-entry form only, as we will specify in the applicable prospectus supplement. This means securities may be represented by one or more global securities registered in the name of a financial institution that holds them as depositary on behalf of other financial institutions that participate in the depositary's book-entry system. These participating institutions, which are referred to as participants, in turn, hold beneficial interests in the securities on behalf of themselves or their customers.

Only the person in whose name a security is registered is recognized as the holder of that security. Securities issued in global form will be registered in the name of the depositary or its participants. Consequently, for securities issued in global form, we will recognize only the depositary as the holder of the securities, and we will make all payments on the securities to the depositary. The depositary passes along the payments it receives to its participants, which in turn pass the payments along to their customers who are the beneficial owners. The depositary and its participants do so under agreements they have made with one another or with their customers; they are not obligated to do so under the terms of the securities.

As a result, investors in a book-entry security will not own securities directly. Instead, they will own beneficial interests in a global security, through a bank, broker or other financial institution that participates in the depositary's book-entry system or holds an interest through a participant. As long as the securities are issued in global form, investors will be indirect holders, and not legal holders, of the securities.

**Street Name Holders** 

We may terminate a global security or issue securities in non- global form. In these cases, investors may choose to hold their securities in their own names or in "street name." Securities held by an investor in street name would be registered in the name of a bank, broker or other financial institution that the investor chooses, and the investor would hold only a beneficial interest in those securities through an account he or she maintains at that institution.

For securities held in street name, we or any applicable trustee or depositary will recognize only the intermediary banks, brokers and other financial institutions in whose names the securities are registered as the holders of those securities, and we or any applicable trustee or depositary will make all payments on those securities to them. These institutions pass along the payments they receive to their customers who are the beneficial owners, but only because they agree to do so in their customer agreements or because they are legally required to do so. Investors who hold securities in street name will be indirect holders, not holders, of those securities.

**Legal Holders** 

Our obligations, as well as the obligations of any applicable trustee and of any third parties employed by us or a trustee, run only to the legal holders of the securities. We do not have obligations to investors who hold beneficial interests in global securities, in street name or by any other indirect means. This will be the case whether an investor chooses to be an indirect holder of a security or has no choice because we are issuing the securities only in global form.

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For example, once we make a payment or give a notice to the legal holder, we have no further responsibility for the payment or notice even if that legal holder is required, under agreements with depositary participants or customers or by law, to pass it along to the indirect holders but does not do so. Similarly, we may want to obtain the approval of the legal holders to amend an indenture, to relieve us of the consequences of a default or of our obligation to comply with a particular provision of the indenture or for other purposes. In such an event, we would seek approval only from the legal holders, and not the indirect holders, of the securities. Whether and how the legal holders contact the indirect legal holders is up to the legal holders.

**Special Considerations for Indirect Holders** 

If you hold securities through a bank, broker or other financial institution, either in book-entry form because the securities are represented by one or more global securities or in street name, you should check with your own institution to find out:

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;• how it handles securities payments and notices;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;• whether it imposes fees or charges;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;• how it would handle a request for the holders' consent, if ever required;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;• whether and how you can instruct it to send you securities registered in your own name so you can be a holder, if
that is permitted in the future;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;• how it would exercise rights under the securities if there were a default or other event triggering the need for
holders to act to protect their interests; and

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;• if the securities are in book-entry form, how the depositary's rules and procedures will affect these
matters.

**Global Securities** 

A global security is a security that represents one or any other number of individual securities held by a depositary. Generally, all securities represented by the same global securities will have the same terms.

Each security issued in book-entry form will be represented by a global security that we deposit with and register in the name of a financial institution or its nominee that we select. The financial institution that we select for this purpose is called the depositary. Unless we specify otherwise in the applicable prospectus supplement, DTC will be the depositary for all securities issued in book-entry form.

A global security may not be transferred to or registered in the name of anyone other than the depositary, its nominee or a successor depositary, unless special termination situations arise. We describe those situations below under the section titled "Special Situations When a Global Security Will Be Terminated" in this prospectus. As a result of these arrangements, the depositary, or its nominee, will be the sole registered owner and legal holder of all securities represented by a global security, and investors will be permitted to own only beneficial interests in a global security. Beneficial interests must be held by means of an account with a broker, bank or other financial institution that in turn has an account with the depositary or with another institution that does. Thus, an investor whose security is represented by a global security will not be a legal holder of the security, but only an indirect holder of a beneficial interest in the global security.

If the prospectus supplement for a particular security indicates that the security will be issued in global form only, then the security will be represented by a global security at all times unless and until the global security is terminated. If termination occurs, we may issue the securities through another book-entry clearing system or decide that the securities may no longer be held through any book-entry clearing system.

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**Special Considerations for Global Securities** 

The rights of an indirect holder relating to a global security will be governed by the account rules of the investor's financial institution and of the depositary, as well as general laws relating to securities transfers. We do not recognize an indirect holder as a holder of securities and instead deal only with the depositary that holds the global security.

If securities are issued only in the form of a global security, an investor should be aware of the following:

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;• an investor cannot cause the securities to be registered in his or her name, and cannot obtain non-global certificates for his or her interest in the securities, except in the special situations we describe below;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;• an investor will be an indirect holder and must look to his or her own bank or broker for payments on the
securities and protection of his or her legal rights relating to the securities, as we describe above;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;• an investor may not be able to sell interests in the securities to some insurance companies and to other
institutions that are required by law to own their securities in non-book-entry form;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;• an investor may not be able to pledge his or her interest in a global security in circumstances where
certificates representing the securities must be delivered to the lender or other beneficiary of the pledge in order for the pledge to be effective;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;• the depositary's policies, which may change from time to time, will govern payments, transfers, exchanges
and other matters relating to an investor's interest in a global security;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;• we and any applicable trustee have no responsibility for any aspect of the depositary's actions or for its
records of ownership interests in a global security, nor do we or any applicable trustee supervise the depositary in any way;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;• the depositary may, and we understand that DTC will, require that those who purchase and sell interests in a
global security within its book-entry system use immediately available funds, and your broker or bank may require you to do so as well; and

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;• financial institutions that participate in the depositary's book-entry system, and through which an
investor holds its interest in a global security, may also have their own policies affecting payments, notices and other matters relating to the securities.

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;• There may be more than one financial intermediary in the chain of ownership for an investor. We do not monitor
and are not responsible for the actions of any of those intermediaries.

**Special Situations When a Global Security Will Be Terminated** 

In a few special situations described below, the global security will terminate and interests in it will be exchanged for physical certificates representing those interests. After that exchange, the choice of whether to hold securities directly or in street name will be up to the investor. Investors must consult their own banks, brokers or other financial institutions to find out how to have their interests in securities transferred to their own name, so that they will be direct holders. We have described the rights of holders and street name investors above.

Unless we provide otherwise in the applicable prospectus supplement, the global security will terminate when the following special situations occur:

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;• if the depositary notifies us that it is unwilling, unable or no longer qualified to continue as depositary for
that global security and we do not appoint another institution to act as depositary within 90 days;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;• if we notify any applicable trustee that we wish to terminate that global security; or

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;• if an event of default has occurred with regard to securities represented by that global security and has not
been cured or waived.

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&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;• The applicable prospectus supplement may also list additional situations for terminating a global security that
would apply only to the particular series of securities covered by the applicable prospectus supplement. When a global security terminates, the depositary, and not we or any applicable trustee, is responsible for deciding the names of the
institutions that will be the initial direct holders.

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**PLAN OF DISTRIBUTION** 

We may sell the securities from time to time pursuant to underwritten public offerings, direct sales to the public, negotiated transactions, block trades or a combination of these methods. A distribution of these securities offered by this prospectus may also be effected through the issuance of derivative securities, including without limitation, warrants. We may sell the securities to or through underwriters or dealers, through agents, or directly to one or more purchasers. We may distribute securities from time to time in one or more transactions:

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;• at a fixed price or prices, which may be changed;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;• at market prices prevailing at the time of sale;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;• at prices related to such prevailing market prices; or

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;• at negotiated prices.

We may also sell equity securities covered by this registration statement in an "at the market offering" as defined in Rule 415(a)(4) under the Securities Act. Such offering may be made into an existing trading market for such securities in transactions at other than a fixed price, either:

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;• on or through the facilities of the Nasdaq Global Select Market or any other securities exchange or quotation or
trading service on which such securities may be listed, quoted or traded at the time of sale; and/or

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;• to or through a market maker other than on the Nasdaq Global Select Market or such other securities exchanges or
quotation or trading services.

Such at-the-market offerings, if any, may be conducted by underwriters acting as principal or agent.

A prospectus supplement or supplements (and any related free writing prospectus that we may authorize to be provided to you) will describe the terms of the offering of the securities, including, to the extent applicable:

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;• the name or names of the underwriters, dealers or agents, if any;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;• the purchase price of the securities or other consideration therefor, and the proceeds, if any, we will receive
from the sale;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;• any over-allotment options under which underwriters may purchase additional securities from us;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;• any agency fees or underwriting discounts and other items constituting agents' or underwriters'
compensation;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;• any public offering price;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;• any discounts or concessions allowed or reallowed or paid to dealers; and

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;• any securities exchange or market on which the securities may be listed.

Only underwriters named in the prospectus supplement will be underwriters of the securities offered by the prospectus supplement.

If underwriters are used in the sale, they will acquire the securities for their own account and may resell the securities from time to time in one or more transactions at a fixed public offering price or at varying prices determined at the time of sale. The obligations of the underwriters to purchase the securities will be subject to the conditions set forth in the applicable underwriting agreement. We may offer the securities to the public through underwriting syndicates represented by managing underwriters or by underwriters without a syndicate. Subject to certain conditions, the underwriters will be obligated to purchase all of the securities offered by the prospectus supplement, other than securities covered by any over-allotment option. Any public offering price and any

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discounts or concessions allowed or reallowed or paid to dealers may change from time to time. We may use underwriters with whom we have a material relationship. We will describe in the prospectus supplement, naming the underwriter, the nature of any such relationship.

We may sell securities directly or through agents we designate from time to time. We will name any agent involved in the offering and sale of securities and we will describe any commissions we will pay the agent in the prospectus supplement. Unless the prospectus supplement states otherwise, our agent will act on a best-efforts basis for the period of its appointment.

We may authorize agents or underwriters to solicit offers by certain types of institutional investors to purchase securities from us at the public offering price set forth in the prospectus supplement pursuant to delayed delivery contracts providing for payment and delivery on a specified date in the future. We will describe the conditions to these contracts and the commissions we must pay for solicitation of these contracts in the prospectus supplement.

We may provide agents and underwriters with indemnification against civil liabilities related to this offering, including liabilities under the Securities Act, or contribution with respect to payments that the agents or underwriters may make with respect to these liabilities. Agents and underwriters may engage in transactions with, or perform services for, us in the ordinary course of business.

All securities we may offer, other than common stock, will be new issues of securities with no established trading market. Any underwriters may make a market in these securities, but will not be obligated to do so and may discontinue any market making at any time without notice. We cannot guarantee the liquidity of the trading markets for any securities. There is currently no market for any of the offered securities, other than our common stock which is listed on the Nasdaq Global Select Market. We have no current plans for listing of the preferred stock, debt securities or warrants on any securities exchange or quotation system; any such listing with respect to any particular preferred stock, debt securities or warrants will be described in the applicable prospectus supplement or other offering materials, as the case may be.

Any underwriter may engage in over-allotment, stabilizing transactions, short-covering transactions and penalty bids in accordance with Regulation M under the Exchange Act. Over-allotment involves sales in excess of the offering size, which create a short position. Stabilizing transactions permit bids to purchase the underlying security so long as the stabilizing bids do not exceed a specified maximum price. Syndicate-covering or other short-covering transactions involve purchases of the securities, either through exercise of the over-allotment option or in the open market after the distribution is completed, to cover short positions. Penalty bids permit the underwriters to reclaim a selling concession from a dealer when the securities originally sold by the dealer are purchased in a stabilizing or covering transaction to cover short positions. Those activities may cause the price of the securities to be higher than it would otherwise be. If commenced, the underwriters may discontinue any of the activities at any time. These transactions may be effected on any exchange or over-the-counter market or otherwise.

Any underwriters or agents that are qualified market makers on the Nasdaq Global Select Market may engage in passive market making transactions in the common stock on the Nasdaq Global Select Market in accordance with Regulation M under the Exchange Act, during the business day prior to the pricing of the offering, before the commencement of offers or sales of the common stock. Passive market makers must comply with applicable volume and price limitations and must be identified as passive market makers. In general, a passive market maker must display its bid at a price not in excess of the highest independent bid for such security; if all independent bids are lowered below the passive market maker's bid, however, the passive market maker's bid must then be lowered when certain purchase limits are exceeded. Passive market making may stabilize the market price of the securities at a level above that which might otherwise prevail in the open market and, if commenced, may be discontinued at any time.

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In compliance with guidelines of the Financial Industry Regulatory Authority, or FINRA, the maximum consideration or discount to be received by any FINRA member or independent broker dealer may not exceed 8% of the aggregate amount of the securities offered pursuant to this prospectus and any applicable prospectus supplement.

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**LEGAL MATTERS** 

Cooley LLP will pass upon certain legal matters in connection with this offering and the validity of the securities offered by this prospectus, and any supplement thereto, unless otherwise indicated in the applicable prospectus supplement. Additional legal matters may be passed upon for us or any underwriters, dealers or agents, by counsel that we will name in the applicable prospectus supplement.

**EXPERTS** 

The consolidated financial statements of Annexon, Inc. as of December 31, 2023 and 2022, and for each of the years in the two-year period ended December 31, 2023, have been incorporated by reference herein and in the registration statement in reliance upon the report of KPMG LLP, independent registered public accounting firm, incorporated by reference herein, and upon the authority of said firm as experts in accounting and auditing.

**WHERE YOU CAN FIND MORE INFORMATION** 

This prospectus is part of the registration statement on Form S-3 we filed with the SEC under the Securities Act and does not contain all the information set forth in the registration statement. Whenever a reference is made in this prospectus to any of our contracts, agreements or other documents, the reference may not be complete and you should refer to the exhibits that are a part of the registration statement or the exhibits to the reports or other documents incorporated by reference into this prospectus for a copy of such contract, agreement or other document. Neither we nor any agent, underwriter or dealer has authorized any person to provide you with different information. We are not making an offer of these securities in any state where the offer is not permitted. You should not assume that the information in this prospectus is accurate as of any date other than the date on the front page of this prospectus, regardless of the time of delivery of this prospectus or any sale of the securities offered by this prospectus. Because we are subject to the information and reporting requirements of the Exchange Act, we file annual, quarterly and current reports, proxy statements and other information with the SEC. Our SEC filings are available to the public over the internet at the SEC's website at <u>http://www.sec.gov</u>. We maintain a website at www.annexonbio.com. The information contained in, or that can be accessed through, our website is not part of this prospectus.

**INCORPORATION BY REFERENCE** 

The SEC allows us to incorporate by reference information into this prospectus from other documents that we file with it, which means that we can disclose important information to you by referring you to those documents. The information incorporated by reference is considered to be part of this prospectus. Information in this prospectus supersedes information incorporated by reference that we filed with the SEC prior to the date of this prospectus, while information that we file later with the SEC will automatically update and supersede the information in this prospectus. We incorporate by reference into this prospectus and the registration statement of which this prospectus is a part the information or documents listed below that we have filed with the SEC and any future filings made by us with the SEC (other than Current Reports or portions thereof furnished under Item 2.02 or Item 7.01 of Form 8-K and exhibits filed on such form that are related to such items and other portions of documents that are furnished, but not filed, or are otherwise not incorporated into registration statements pursuant to applicable rules promulgated by the SEC) that are filed by us with the SEC pursuant to Sections 13(a), 13(c), 14 or 15(d) of the Exchange Act (i) after the date of the filing of the registration statement of which this prospectus is a part and prior to effectiveness of the registration statement, and (ii) after the effectiveness of the registration statement but prior to the termination of all offerings of securities covered by this prospectus:

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;• our Annual Report on [Form 10-K](http://www.sec.gov/Archives/edgar/data/../../../ix?doc=/Archives/edgar/data/0001528115/000095017024036408/annx-20231231.htm) for the year ended December 31, 2023, filed with the SEC on March 26, 2024; and

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&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;• the description of our common stock contained in our registration statement on [Form 8-A](http://www.sec.gov/Archives/edgar/data/1528115/000119312520196463/d90014d8a12b.htm) dated July 
21, 2020, including all amendments and reports filed for the purpose of updating such description, including the description of our common stock in [Exhibit 4.3](http://www.sec.gov/Archives/edgar/data/1528115/000156459022008044/annx-ex43_9.htm) to our Annual Report on Form 10-K for the year ended December 31, 2021, filed with the SEC on March 1, 2022.

Any statement contained herein or in a document incorporated or deemed to be incorporated by reference into this document will be deemed to be modified or superseded for purposes of the document to the extent that a statement contained in this document or any other subsequently filed document that is deemed to be incorporated by reference into this document modifies or supersedes the statement.

We will furnish without charge to each person, including any beneficial owner, to whom a prospectus is delivered, upon written or oral request, a copy of any or all of the documents incorporated by reference into this prospectus but not delivered with the prospectus, including exhibits that are specifically incorporated by reference into such documents. Any such request may be made by writing or telephoning us at the following address or phone number:

1400 Sierra Point Parkway, Bldg C, Suite 200

Brisbane, CA 94005

(650) 822-5500

Attention: Investor Relations

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**25,096,153 Shares of Common Stock** 

**Pre-Funded Warrants to Purchase up to 3,750,000 Shares of Common Stock**![LOGO](g34136g00r00.jpg)

**Prospectus Supplement** 

**Goldman Sachs & Co. LLC** 

**TD Cowen** 

**Wells Fargo Securities**