T-cell lymphomas (TCLs) are characterised by poor responses to therapy with brief durations of remissions. An early phase study of pralatrexate has demonstrated dramatic activity in patients with relapsed/refractory disease. Of the first 20 lymphoma patients treated, 16 had B-cell lymphoma and four had refractory aggressive TCL. All four patients with TCL achieved a complete remission. Patients with B-cell lymphoma achieved stable disease at best. For each TCL patient, the response was more durable than their best response with chemotherapy. This early experience is the first to document this unique activity of pralatrexate in TCL.