ALTH Allos Therapeutics, Inc. (MM)

As filed with the Securities and Exchange Commission on June 24, 2008

Registration No. 333-134654

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

POST-EFFECTIVE AMENDMENT NO. 1

TO

FORM S-8

REGISTRATION STATEMENT

UNDER

THE SECURITIES ACT OF 1933

ALLOS THERAPEUTICS, INC.

(Exact name of registrant as specified in its charter)

11080 CirclePoint Road, Suite 200

Westminster, Colorado 80020

(Address of principal executive offices)

2006 Inducement Award Plan

(Full title of the plan)

Paul L. Berns

President and Chief Executive Officer

Allos Therapeutics, Inc.

11080 CirclePoint Road, Suite 200

Westminster, Colorado 80020

(303) 426-6262

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

Copies to:

James C. T. Linfield, Esq.

Brent D. Fassett, Esq.

COOLEY GODWARD KRONISH LLP

380 Interlocken Crescent, Suite 900

Broomfield, Colorado 80021

(720) 566-4000

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

DEREGISTRATION OF UNSOLD SECURITIES

This Post-Effective Amendment No. 1 to Form S-8 Registration Statement relates to the Registration Statement on Form S-8 (File No. 333-134654) (the “Registration Statement”) of Allos Therapeutics, Inc. (the “Company”) pertaining to 1,500,000 shares of the Company’s common stock, par value $0.001 per share, which was filed with the Securities and Exchange Commission and became effective on June 1, 2006.  The Registration Statement registered 1,500,000 shares of common stock for sale pursuant to the Company’s 2006 Inducement Award Plan (the “2006 Plan”).

On June 24, 2008 (the “Effective Date”), the stockholders of the Company approved the Company’s 2008 Equity Incentive Plan (the “2008 Plan”).  The 2008 Plan is intended as the successor to and continuation of the 2006 Plan.  As of the Effective Date of the 2008 Plan, all shares remaining available for issuance under the 2006 Plan became available for issuance under the 2008 Plan and all outstanding stock awards granted under the 2006 Plan were deemed granted pursuant to the 2008 Plan, but remain subject to the terms of the 2006 Plan.  As of the Effective Date, no additional stock awards will be granted under the 2006 Plan.  The Company intends to file a new Form S-8 Registration Statement pertaining to the 2008 Plan.

Subject to the foregoing, and in accordance with an undertaking made by the Company in the Registration Statement to remove from registration, by means of a post-effective amendment, any of the securities registered under the Registration Statement that remain unsold at the termination of the offering, the Company hereby removes from registration the securities of the Company registered but unsold under the Registration Statement.

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SIGNATURES

Pursuant to the requirements of the Securities Act of 1933, as amended, the Registrant certifies that it has reasonable grounds to believe that it meets all of the requirements for filing on Form S-8 and has duly caused this Post-Effective Amendment No. 1 to Registration Statement to be signed on its behalf by the undersigned, thereunto duly authorized, in the City of Westminster, State of Colorado, on June 24, 2008.

Pursuant to the requirements of the Securities Act of 1933, this Post-Effective Amendment No. 1 to Registration Statement has been signed by the following persons in the capacities and on the dates indicated.

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