FDA's Oncologic Drugs Advisory Committee votes in favor of FOLOTYN NDA

Allos Therapeutics, Inc. (Nasdaq: ALTH) today announced that the U.S. Food and Drug Administration’s (FDA) Oncologic Drugs Advisory Committee (ODAC) voted 10-4 that the response rate and duration of response observed with FOLOTYN^TM (pralatrexate) are reasonably likely to predict clinical benefit in patients with relapsed or refractory peripheral T-cell lymphoma (PTCL). PTCL comprises a biologically diverse group of aggressive blood cancers that has a worse prognosis than most other types of lymphoma, including B-cell lymphoma. If approved, FOLOTYN would be the first drug approved by the FDA for the treatment of relapsed or refractory PTCL.

The ODAC recommendation was based on results from PROPEL, a pivotal Phase 2 international trial that evaluated FOLTYN for the treatment of patients with relapsed or refractory PTCL. The PROPEL trial was conducted under an agreement reached with the FDA under its special protocol assessment, or SPA, process. The SPA process allows for FDA evaluation of a clinical trial protocol intended to form the primary basis of an efficacy claim in support of an NDA, and provides an agreement that the trial design, including trial size, clinical endpoints and data analyses are acceptable to the FDA.

The FDA is expected to make a decision whether to approve the Company’s New Drug Application (NDA) for FOLOTYN by September 24, 2009. While the FDA generally follows the recommendations of its advisory committees, it is not required to do so.

“We are very pleased that the advisory committee today voted to recommend accelerated approval of the FOLOTYN NDA,” said Paul L. Berns, chief executive officer at Allos Therapeutics, Inc. “We believe FOLOTYN has the potential to offer an important new treatment option for patients with relapsed or refractory PTCL, an indication for which there are currently no FDA-approved therapies and no accepted standard of care. We will continue to work with FDA to bring FOLOTYN to the U.S. market as soon as possible so that patients can benefit from this potential new treatment option.”

About Pralatrexate

Pralatrexate is a selective antifolate designed to accumulate preferentially in cancer cells. Based on preclinical studies, the Company believes that pralatrexate selectively enters cells expressing RFC-1, a protein that is over expressed on certain cancer cells compared to normal cells. Once inside cancer cells, pralatrexate is efficiently polyglutamylated, which leads to high intracellular drug retention. Polyglutamylated pralatrexate essentially becomes “trapped” inside cancer cells, making it less susceptible to efflux-based drug resistance. Acting on the folate pathway, pralatrexate interferes with DNA synthesis and triggers cancer cell death.