As filed with the Securities and Exchange Commission on January 22, 2018.

Registration Statement No. 333-222640

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

Amendment No. 1 to

FORM S-1

REGISTRATION STATEMENT

UNDER

THE SECURITIES ACT OF 1933

ATHENEX, INC.

(Exact Name of Registrant as Specified in Its Charter)

1001 Main Street, Suite 600

Buffalo, NY 14203

(716) 427-2950

(Address, including zip code and telephone number, including area code, of registrant’s principal executive offices)

Johnson Y.N. Lau

Chief Executive Officer

Athenex, Inc.

1001 Main Street, Suite 600

Buffalo, NY 14203

(716) 427-2950

(Name, address, including zip code, and telephone number, including area code, of agent for service)

Copies to:

Approximate date of commencement of proposed sale to the public:

As soon as practicable after this Registration Statement becomes effective.

If any of the securities being registered on this Form are to be offered on a delayed or continuous basis pursuant to Rule 415 under the Securities Act, check the following box.  ☐

If this Form is filed to register additional securities for an offering pursuant to Rule 462(b) under the Securities Act, please check the following box and list the Securities Act registration statement number of the earlier effective registration statement for the same offering.  ☐

If this Form is a post-effective amendment filed pursuant to Rule 462(c) under the Securities Act, check the following box and list the Securities Act registration statement number of the earlier effective registration statement for the same offering.  ☐

If this Form is a post-effective amendment filed pursuant to Rule 462(d) under the Securities Act, check the following box and list the Securities Act registration statement number of the earlier effective registration statement for the same offering.  ☐

Indicate by check mark whether the registrant is a large accelerated filer, an accelerated filer, a non-accelerated filer, smaller reporting company or an emerging growth company. See the definitions of “large accelerated filer,” “accelerated filer”, “smaller reporting company” and “emerging growth company” in Rule 12b-2 of the Exchange Act. (Check one):

If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 7(a)(2)(B) of the Securities Act.  ☒

CALCULATION OF REGISTRATION FEE

The Registrant hereby amends this Registration Statement on such date or dates as may be necessary to delay its effective date until the Registrant shall file a further amendment which specifically states that this Registration Statement shall thereafter become effective in accordance with Section 8(a) of the Securities Act of 1933, as amended, or until the Registration Statement shall become effective on such date as the Commission, acting pursuant to said Section 8(a), may determine.

EXPLANATORY NOTE

Athenex, Inc. is filing this Amendment No. 1, or “Amendment,” to its registration statement on Form S-1 (File No. 333-222640), or the “Registration Statement,” solely to file Exhibit 1.1 and make related changes to the exhibit index. Accordingly, this Amendment consists only of the facing page, this explanatory note, Part II of the Registration Statement and the exhibit filed herewith. The preliminary prospectus is unchanged and has therefore been omitted.

PART II

INFORMATION NOT REQUIRED IN PROSPECTUS

Item 13. Other Expenses of Issuance and Distribution

The following table sets forth the costs and expenses, other than underwriting discounts and commissions, payable in connection with the sale and distribution of the securities being registered. All amounts are estimated except the SEC and FINRA registration fees. All of the expenses below will be paid by us.

Item 14. Indemnification of Directors and Officers

Under Section 145 of the Delaware General Corporation Law, we can indemnify our directors and officers against liabilities they may incur in such capacities, including liabilities under the Securities Act of 1933, as amended, or the Securities Act. Our amended and restated certificate of incorporation (Exhibit 3.1 to this registration statement) provides that we must indemnify our directors and officers to the fullest extent permitted by law and requires us to pay expenses incurred in defending or other participating in any proceeding in advance of its final disposition upon our receipt of an undertaking by the director or officer to repay such advances if it is ultimately determined that the director or officer is not entitled to indemnification. Our certificate of incorporation further provides that rights conferred under such certificate of incorporation do not exclude any other right such persons may have or acquire under the certificate of incorporation, the bylaws, any statute, agreement, vote of stockholders or disinterested directors or otherwise.

The amended and restated certificate of incorporation also provides that, pursuant to Delaware law, our directors shall not be liable for monetary damages for breach of the directors’ fiduciary duty of care to us and our stockholders. This provision in the amended and restated certificate of incorporation does not eliminate the duty of care, and in appropriate circumstances equitable remedies such as injunctive or other forms of non-monetary relief will remain available under Delaware law. In addition, each director will continue to be subject to liability for breach of the director’s duty of loyalty to us for acts or omissions not in good faith or involving intentional misconduct, or knowing violations of law, for actions leading to improper personal benefit to the director, and for payment of dividends or approval of stock repurchases or redemptions that are unlawful under Delaware law. The provision also does not affect a director’s responsibilities under any other law, such as the federal securities laws or state or federal environmental laws. We also maintain directors’ and officers’ liability insurance.

In addition, we have agreements to indemnify our directors and certain of our officers in addition to the indemnification provided for in the amended and restated certificate of incorporation. These agreements, among other things, indemnify our directors and some of our officers for certain expenses (including attorney’s fees), judgments, fines and settlement amounts incurred by such person in any action or proceeding, including any action by or in our right, on account of services by that person as a director or officer of our company or as a director or officer of our subsidiary, or as a director or officer of any other company or enterprise that the person provides services to at our request.

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The proposed form of underwriting agreement (Exhibit 1.1 to this registration statement) provides for indemnification by the underwriters of us and our officers and directors, and by us of the underwriters, for certain liabilities arising under the Securities Act or otherwise in connection with this offering.

Item 15. Recent Sales of Unregistered Securities

During the last three years we have issued unregistered securities as described below. The share and per share amounts below reflect shares of preferred stock on an as-converted to common stock basis:

Issuances of preferred stock

Issuances of common stock

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Issuances of warrants

Grants of stock options and issuances of common stock upon exercise of options

Issuances of Convertible Loan Agreements

We deemed the offers, sales and issuances of the securities described in paragraphs 1 through 19 and 21 above to be exempt from registration under the Securities Act, in reliance on Section 4(a)(2) of the Securities Act, including Regulation D and Rule 506 promulgated thereunder, relative to transactions by an issuer not involving a public offering. All purchasers of securities in transactions exempt from registration pursuant to Regulation D represented to us that they were accredited investors and were acquiring the shares for investment purposes only and not with a view to, or for sale in connection with, any distribution thereof and that they could bear the risks of the investment and could hold the securities for an indefinite period of time. The purchasers received written disclosures that the securities had not been registered under the Securities Act and that any resale must be made pursuant to a registration statement or an available exemption from such registration.

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We deemed the grants of stock options and issuances of common stock upon exercise of stock options described in paragraph 20 above, except to the extent described above as exempt pursuant to Section 4(2) of the Securities Act, to be exempt from registration under the Securities Act in reliance on Rule 701 of the Securities Act as offers and sales of securities under compensatory benefit plans and contracts relating to compensation in compliance with Rule 701. Each of the recipients of securities in any transaction exempt from registration either received or had adequate access, through employment, business or other relationships, to information about us.

All of the foregoing securities are deemed restricted securities for purposes of the Securities Act. The certificates representing the securities issued in the transactions described in this Item 15 included appropriate legends setting forth that the securities had not been offered or sold pursuant to a registration statement and describing the applicable restrictions on transfer of the securities. There were no underwriters employed in connection with any of the transactions set forth in this Item 15.

Item 16. Exhibits and Financial Statement Schedules

The exhibits to the registration statement are listed in the Exhibit Index attached hereto and incorporated by reference herein.

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SCHEDULE I

CONDENSED FINANCIAL INFORMATION OF REGISTRANT (PARENT COMPANY ONLY)

CONDENSED BALANCE SHEETS

(In thousands, except share and per share data)

This statement should be read in conjunction with the notes to the consolidated financial statements included in the Company’s Form S-1

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SCHEDULE I

CONDENSED FINANCIAL INFORMATION OF REGISTRANT (PARENT COMPANY ONLY)

CONDENSED STATEMENTS OF OPERATIONS AND COMPREHENSIVE LOSS

(In thousands, except share and per share data)

This statement should be read in conjunction with the notes to the consolidated financial statements included in the Company’s Form S-1

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SCHEDULE I

CONDENSED FINANCIAL INFORMATION OF REGISTRANT (PARENT COMPANY ONLY)

CONDENSED STATEMENTS OF CASH FLOWS

(In thousands)

This statement should be read in conjunction with the notes to the consolidated financial statements included in the Company’s Form S-1

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Schedule II—Valuation and Qualifying Accounts

Activity in the following valuation and qualifying accounts consisted of the following (in thousands):

(1) Increases in the allowance for doubtful accounts consist of our provision for bad debts, which is included within selling, general, and administrative expenses on the consolidated statements of operations and comprehensive loss. Decreases in the allowances for doubtful accounts consist of the write-off of specific accounts and the recovery of previously reserved receivables.

(2) Increases in the reserve for excess and obsolete inventory are charged to expense within cost of sales on the consolidated statements of operations and comprehensive loss and are based on the difference, if any, between the cost of the inventory and market, based upon assumptions about future demand. Decreases in the reserve for excess and obsolete inventory consist of the write-off of specific items and the recovery of previously reserved inventory.

(3) Increases in the valuation allowance for deferred income tax assets offset the increase in our gross deferred tax assets, based on the expected realization of those future tax benefits.

Item 17. Undertakings

The registrant hereby undertakes to provide to the underwriters at the closing specified in the underwriting agreement certificates in such denominations and registered in such names as required by the underwriters to permit prompt delivery to each purchaser.

Insofar as indemnification for liabilities arising under the Securities Act may be permitted to directors, officers and controlling persons of the registrant pursuant to the foregoing provisions, or otherwise, the registrant has been advised that in the opinion of the Securities and Exchange Commission such indemnification is against public policy as expressed in the Securities Act and is, therefore, unenforceable. In the event that a claim for indemnification against such liabilities (other than the payment by the registrant of expenses incurred or paid by a director, officer or controlling person of the registrant in the successful defense of any action, suit, or proceeding) is asserted by such director, officer or controlling person in connection with the securities being registered, the registrant will, unless in the opinion of its counsel the matter has been settled by controlling precedent, submit to a court of appropriate jurisdiction the question whether such indemnification by it is against public policy as expressed in the Securities Act and will be governed by the final adjudication of such issue.

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The undersigned registrant hereby undertakes that:

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EXHIBIT INDEX

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SIGNATURES

Pursuant to the requirements of the Securities Act of 1933, as amended, the registrant has duly caused this registration statement to be signed on its behalf by the undersigned, thereunto duly authorized, in the city of Buffalo, State of New York, on January 22, 2018.

KNOW ALL PERSONS BY THESE PRESENTS, the undersigned hereby constitute and appoint Johnson Y.N. Lau and Teresa Bair and each of them, his true and lawful attorney-in-fact and agent, each with full power of substitution and resubstitution, for him and in his name, place and stead, in any and all capacities, to sign any and all amendments (including post-effective amendments) to this registration statement, or any related registration statement filed pursuant to Rule 462(b) under the Securities Act, and to file the same, with exhibits thereto, and other documents in connection therewith, with the Securities and Exchange Commission, granting unto said attorneys-in-fact and agents, and each of them, full power and authority to do and perform each and every act and thing requisite or necessary to be done in connection therewith, as fully to all intents and purposes as he might or could do in person, hereby ratifying and confirming all that each of said attorneys-in-fact and agents, or his substitute or substitutes, may lawfully do or cause to be done by virtue hereof.

IN WITNESS WHEREOF, each of the undersigned has executed this power of attorney as of the date indicated.

Pursuant to the requirements of the Securities Act of 1933, as amended, this Registration Statement on Form S-1 has been signed by the following persons in the capacities indicated on January 22, 2018:

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