Romidepsin Is Effective and Well-Tolerated In Patients ≥ 60 Years Old With Relapsed Or Refractory Peripheral T-Cell Lymphoma (PTCL): Analysis From Phase 2 Trials
Authors: Shustov Andrei R. , Coiffier Bertrand , Horwitz Steven M. , Sokol Lubomir , Pro Barbara , Nielsen Tina , Wolfson Julie , Balser Barbara E , Eisch Robin , Popplewell Leslie , Prince Miles , Allen Steven L. , Piekarz Richard , Bates Susan E. 
Published: October 2019

Abstract

Background
PTCL is a heterogeneous group of mature, post-thymic, T- and natural killer–cell disorders associated with a poor prognosis in most subtypes. Anthracycline-based therapies (eg, CHOP) are most often used in the frontline treatment of PTCL, although they do not typically lead to durable remissions. Older patients may not be eligible for additional chemotherapeutic regimens due to comorbidities and/or poor performance status. Thus, it is important to identify appropriate treatment strategies for older patients with PTCL, particularly in the salvage setting. Romidepsin is a potent class I histone deacetylase inhibitor approved by the FDA for the treatment of patients with PTCL who have received ≥ 1 prior therapy and patients with cutaneous T-cell lymphoma who have received ≥ 1 prior systemic therapy. Approval of PTCL was based on results from the pivotal study of romidepsin for the treatment of relapsed/refractory PTCL (N = 131) that demonstrated durable clinical benefit and tolerability and was supported by a similar study from the National Cancer Institute (N = 47). The objective herein is to present efficacy and safety data for romidepsin specific to older patients (≥ 60 years) with relapsed/refractory PTCL in the pivotal and supportive trials.

Methods
In both trials, patients with PTCL who relapsed from or were refractory to ≥ 1 prior systemic therapy received romidepsin 14 mg/m2 as a 4-hour intravenous infusion on days 1, 8, and 15 of 28-day cycles. For the pivotal trial, the primary endpoint was confirmed/unconfirmed complete response (CR/CRu) determined by an independent review committee. For the supportive trial, the primary endpoints were objective response rate (ORR) and rate of CR by investigator assessment. In this analysis, efficacy and safety data for patients ≥ 60 years old were examined and compared with those for the overall study population.

Results
In the pivotal study, the overall median age was 61 years (range, 20-83); 71/130 patients (55%) were ≥ 60 years old (median 67 years [range, 60-83]) with a median of 2 prior systemic therapies (range, 1-8), including prior stem cell transplant in 7 patients. Response rates in the older population were similar to those seen overall: 25% ORR for both populations, including 14% and 15% with CR/CRu for older vs overall populations, respectively. Also, in both the older and overall populations, the median DOR was 28 months, with the longest response ongoing at 48 months (median follow-up 22.3 months). Of the 10 older patients who achieved CR/CRu, 6 had a DOR of ≥ 12 months. Survival was also similar, with 5 and 4 months PFS and 12 and 11 months OS for the older vs overall populations, respectively. In the supportive trial, the overall median age was 60 (range, 27-84); 23/47 patients (49%) were ≥ 60 years old (median 68 years [range, 61-84]) with a median of 2 prior regimens (range, 1-8), including prior stem cell transplant in 7 patients. Response rates in the older population were similar to those seen overall: 32% and 38% ORR, including 14% and 18% with CR, respectively. The median DOR was 5 months (range, 3-49) and 9 months (range, 2-74+) for the older vs overall populations, respectively. One 79-year-old patient with 6 prior systemic therapies achieved CR on romidepsin and stopped therapy after 6 cycles in consideration of his age. Off therapy, disease progression was observed; romidepsin was restarted per protocol and patient achieved a second CR, receiving an additional 22 cycles of therapy. In both the pivotal and supportive trials, rates of grade ≥ 3 adverse events were similar for the overall vs older patient populations (Table).

Conclusions
In phase 2 trials of romidepsin for the treatment of relapsed/refractory PTCL, patients aged ≥ 60 years comprised approximately half of patients. Both efficacy and safety were similar for the older vs overall populations. Thus, data were not skewed due to age, and romidepsin is suitable for use in elderly patients with relapsed/refractory PTCL.

Disclosures:
Shustov: Celgene Corporation: Honoraria, Research Funding, Speakers Bureau. Coiffier:Celgene Corporation: Consultancy; Spectrum Pharmaceuticals: Consultancy. Horwitz:Celgene Corporation: Consultancy, Research Funding; Spectrum Pharmaceuticals: Consultancy, Research Funding; Seattle Gen: Consultancy, Research Funding; Infinity Pharmaceuticals: Research Funding; Kyowa Hakko Kirin Pharma: Research Funding; Millenium: Consultancy, Research Funding; Genzyme: Consultancy; Janssen: Consultancy. Sokol:Celgene Corporation: Consultancy, Speakers Bureau; Gloucester: Research Funding. Pro:Celgene Corporation: Honoraria. Nielsen:Celgene Corporation: Employment, Equity Ownership. Balser:Celgene Corporation: Consultancy. Prince:Celgene Corporation: Honoraria, Research Funding. Allen:Celgene Corporation: Honoraria. Bates:Celgene Corporation: Research Funding.