Phase II Study of the Fondazione Italiana Linfomi on Gemcitabine Plus Romidepsin (GEMRO Regimen) in Relapsed and Refractory Peripheral T-Cell Lymphoma Patients

Introduction. Relapsed and primary refractory peripheral T-cell lymphomas (PTCL) show a dismal outcome, with a 5-year overall survival of only 30%. There is no standard salvage chemotherapy for these patients. Gemcitabine was proved to be an effective monotherapy, yelding 60-70% overall response rates in patients with advanced heavily pre-treated disease. Romidepsin, a histone deacetylase inhibitor recently approved by Food and Drug Administration, has demonstrate an overall response rate (ORR) of 30% and a complete response (CR) rate of 16%. We have recently designed a multicentric trial to investigate the role of the combination of gemcitabine plus romidepsin (GEMRO regimen) in relapsed or refractory PTCL, looking for a potential synergistic effect of the two drugs.

Methods. Twenty relapsed/refractory PTCL patients were included in a multicentric, prospective phase II trial which contemplated an induction with romidepsin 12 mg/m² intravenously (i.v.) on days 1, 8, 15, and gemcitabine, 800 mg/m² i.v. on day 1 and 15, for 6 cycles, each cycle to be repeated every 28 days. After the induction phase, patient who obtained at least a partial remission (PR) proceeded onto romidepsin maintenance at the dose of 14 mg/m² i.v. until disease progression. The primary endpoint was to evaluate the efficacy of GEMRO regimen after the induction phase, as assessed by complete response (CR) rate; safety assessment was regarded as a secondary objective. The trial was registered under EudraCT (2012-001404-38).

Results. Twenty patients have been recruited for this study. At present time, all patients underwent the induction phase and are evaluable for response and toxicity. The median age of patients was 55 years (range, 24-77). According to histology, 10 patients had PTCL not otherwise specified, 9 had an angioimmunoblastic T-cell lymphoma, 1 had a kinase negative anaplastic large cell lymphoma. The median number of prior therapies was 2 (range, 1-4); 7/20 (35%) patients had failed a prior stem cell transplant. Nineteen out of 20 (95%) patients presented with advanced stage. At the end of induction phase, the ORR was 31% including 2 CRs and 3 PRs. One of the 2 CR patients discontinued the treatment after 4 cycles due to cardiac toxicity, however maintaining a continuous CR with a follow up of 2 years. The other CR patient is still on treatment in maintenance phase. Grade ≥3 adverse events were represented by thrombocytopenia (60%), neutropenia (50%), and anemia (20%).

Conclusions. To date, data failed to show a superiority of the GEMRO combination regimen over single agent romidepsin as salvage therapy for refractory or relapsed PTCL patients. More mature data and an adequate follow-up will be required to better understand the role of this combination regimen.