Phase II study of the novel antifolate agent pralatrexate in combination with the histone deacetylase inhibitor romidepsin for the treatment of patients with mature T-cell lymphoma

Previously, we conducted a Phase I study of the combination of pralatrexate and romidepsin in patients with relapsed/refractory (R/R) lymphomas and subsequently conducted a multicenter Phase II study in patients with untreated or R/R mature T cell lymphomas (MTCL). Patients received pralatrexate 25 mg/m2 and romidepsin 12 mg/m2 every 2 weeks. Fourteen patients were evaluable for efficacy. Overall response rate was 35.7% with CR in 14.3% and disease control in 50%. The mDOR was 8.2 months, mPFS was 3.6 months, and mOS was 20.2 months. Gastrointestinal side effects were most common in up to 33%; there was only one hematologic toxicity of grade 3 anemia. Combining results of MTCL patients from the Phase I and II studies (N = 28), the ORR was 53.5% with CR in 21.4%, disease control in67.8%, and DOR of 7.2 months. The combination was safe however does not out-perform other combination strategies.Trial Registration: www.clinicaltrials.gov (NCT01947140).