Exhibit 10.13.1

[*] = CERTAIN CONFIDENTIAL INFORMATION CONTAINED IN THIS DOCUMENT, MARKED BY BRACKETS, HAS BEEN OMITTED AND FILED SEPARATELY WITH THE SECURITIES
AND EXCHANGE COMMISSION PURSUANT TO RULE 24B-2 OF THE SECURITIES ACT OF 1934, AS AMENDED.

SECOND AMENDMENT TO
LICENSE AGREEMENT

ThisSECOND AMENDMENT TO LICENSE AGREEMENT(this "Second
Amendment"), dated as of November 6 2007, is entered into betweenSRIINTERNATIONAL, a California
not-for-profit corporation ("SRI"),SLOAN-KETTERING INSTITUTE FOR CANCER
RESEARCH, a New York not-for-profit corporation ("SKI"),SOUTHERN RESEARCH
INSTITUTE, an Alabama not-for-profit corporation ("SoRI" and, together with SRI and SKI, the
"Licensor"), andALLOS THERAPEUTICS, INC., a Delaware corporation
("Allos"). Allos and Licensor are each sometimes individually referred to herein as a "Party" and
collectively as the "Parties."

WITNESSETH

WHEREAS, the Parties entered into that certain License Agreement dated as of
December 23, 2002 (the"Original Agreement"), pursuant to which Allos obtained from Licensor an exclusive license to certain patent rights and
know-how relating to a proprietary compound known as PDX in exchange for certain rights and consideration provided to Licensor;

WHEREAS, the Parties entered into a First Amendment to the Original Agreement dated as of May 9, 2006 (the
"First Amendment") (the Original Agreement and First Amendment are sometimes collectively referred to herein as the "License
Agreement");

WHEREAS, the Parties now desire to further amend the License Agreement to modify the terms and conditions relating to certain payments
payable to Licensor thereunder;

NOW, THEREFORE, in consideration of the foregoing premises and for other good and valuable consideration, the receipt and sufficiency of
which are hereby acknowledged, the Parties hereby agree as follows:

AGREEMENT

1.All capitalized terms used but not defined herein shall have the meanings assigned to them in the License Agreement.

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2.Section 3.3 of the License Agreement is hereby deleted in its entirety and replaced with the following:



Milestone

Amount1. The earlier of: (a) enrollment of the first patient in a multi-center, Allos-sponsored Phase II Trial; or (b) eighteen (18) months
from the Effective Date.

$
1,000,000 (Paid)2. The earlier of: (a) enrollment of the first patient in an Allos-sponsored Registration Trial (as defined below);
or (b) four (4) years from the Effective Date, payable at the rate of $500,000 per year until enrollment of the first patient in an Allos-sponsored Registration Trial, at which time the balance shall be paid in full.

$
2,000,000 ($500,000 Paid)3. FDA acceptance of NDA for review.

$
1,500,0004. US FDA approval for sale of Product.

$
5,300,0005. EU Approval for sale of Product.

$
3,500,000




3.Licensor hereby represents and warrants to Allos that: (a) it has taken all necessary corporate action to authorize
the execution and delivery of this Second Amendment; and (b) this Second Amendment has been duly executed and delivered on behalf of Licensor, and constitutes a legal, valid, binding
obligation, enforceable against Licensor in accordance with its terms.

4.This Second Amendment shall be made part of the Agreement and be governed by all its terms.

5.This Second Amendment may be executed in two or more counterparts, each of which shall be deemed an original, but all of
which together shall constitute one and the same instrument.

6.This Second Amendment shall be effective upon its execution by each of SRI, SKI, SoRl and Allos.

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IN WITNESS WHEREOF, the parties have caused this Second Amendment to be executed by their duly authorized representatives as of the date
first set forth above.

SRI INTERNATIONAL

ALLOS THERAPEUTICS, INC.By:

/s/ JOHN MCINTIRE

By:

/s/ MARC H. GRABOYESName:

John McIntire

Name:

Marc H. GraboyesTitle:

Deputy General Counsel

Title:

Vice President, General CounselSLOAN-KETTERING INSTITUTE FOR CANCER RESEARCH

SOUTHERN RESEARCH INSTITUTEBy:

/s/ GUSTAVE BERNHARDT

By:

/s/ DAVID W. MASONGustave J. Bernhardt

Name:

David W. MasonTitle:

Director, Research Resources Management

Title:

Director CIP


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