Safety and efficacy of pralatrexate in the management of relapsed or refractory peripheral T-cell lymphoma.

Peripheral T-cell lymphoma (PTCL) represents a relatively rare group of heterogeneous non-Hodgkin lymphomas, with generally poor prognosis. Historically, there has been a lack of consensus regarding appropriate therapeutic measures for the disease, with conventional frontline chemotherapies being utilized in most cases. Following promising results obtained in 2009, the methotrexate analogue, pralatrexate, became the first drug to gain US FDA approval for the treatment of refractory PTCL. This antimetabolite was designed to have a higher affinity for reduced folate carrier (RFC) and folylpolyglutamate synthetase (FPGS). RFC is the principal transporter for cell entrance of folates and antifolates. Once inside the cell, pralatrexate is efficiently polyglutamated by FPGS. Pralatrexate has demonstrated varying degrees of efficacy in peripheral T-cell lymphoma, with response rates differing between the multiple subtypes of the disease. While phase III studies are still to be completed, early clinical trials indicate that pralatrexate is promising new therapeutic for PTCL.