August 3, 2006

The FDA has granted orphan drug status to Allos' T-cell lymphoma drug PDX, the company said.

Peripheral T-cell lymphomas (PTCLs) account for approximately 10 percent to 15 percent of all cases of non-Hodgkin's lymphoma (NHL). Interim results from a Phase I/II study of PDX in patients with relapsed or refractory NHL and Hodgkin's lymphoma showed that four of seven patients with T-cell lymphoma completely recovered following treatment with PDX, despite having failed several prior chemotherapies, Allos said.

PDX (pralatrexate) inhibits an enzyme involved in the building of DNA, which is necessary for cell replication.

Orphan products are developed to treat rare diseases or conditions that affect fewer than 200,000 people in the U.S. The designation provides the developer with such incentives as a waiver of filing fees, grants for clinical trials and seven years of marketing exclusivity.

The average five-year survival rate for PTCL patients is approximately 25 percent. There are currently no pharmaceutical agents approved for the treatment of relapsed or refractory PTCLs.

Allos said it plans to commence a Phase II study of PDX in patients with relapsed or refractory peripheral T-cell lymphoma in the third quarter of 2006.