Phase I/Ii Multicenter Study Of Romidepsin In Japanese Patients With Relapsed Or Refractory Peripheral T-Cell Lymphoma

Abstract Introduction: Peripheral T-cell lymphoma (PTCL) is an aggressive lymphoma associated with poor prognosis. There is no consensus on standard therapy, and options are limited for patients with relapsed/refractory (R/R) disease. Romidepsin, a potent histone deacetylase inhibitor, has US FDA approval for patients with >=1 prior treatment for PTCL based on 25%-38% overall response rates (ORR) and durable responses (Piekarz et al, Blood. 2011;117:5827; Coiffier et al, J Clin Oncol. 2012;30:631). Here we report results from the phase I/II, multicenter, open-label study of romidepsin in Japanese patients with R/R PTCL or cutaneous T-cell lymphoma (CTCL) (TCL-001; NCT01456039). Methods: Patients aged >=20 years with R/R PTCL or CTCL received romidepsin via a 4-hour IV infusion on days 1, 8, and 15 of each 28-day cycle until progressive disease or unacceptable toxicity. The phase I portion of the study used a 3+3 design to identify any dose-limiting toxicity (DLT; phase I primary endpoint) with romidepsin 9 mg/m2 (cohort 1) and 14 mg/m2 (cohort 2). The phase II dose was based on the highest dose where <=2 of 6 patients experienced a DLT in phase I. The primary endpoint for phase II was ORR; secondary endpoints included time to response (TTR), duration of response (DOR), time to progression (TTP), and toxicity. Toxicity was assessed per NCI CTCAE version 3.0. Efficacy was assessed per modified 1999 IWG response criteria for non-Hodgkin lymphoma, descriptive statistics, and Kaplan-Meier method. Pharmacokinetic (PK) assessments included all patients in phase I with concentration-time data to enable PK parameter calculations for >=1 day. Assessments of the intent-to-treat (ITT) population included all patients receiving at least 1 dose of romidepsin. Results: The ITT population comprised 48 patients with PTCL and 2 with CTCL (1 each in the 9 and 14 mg/m2 cohorts). The common PTCL subtypes were angioimmunoblastic T-cell lymphoma (AITL, n=21, 44%), PTCL not otherwise specified (PTCL-NOS, n=20, 42%), and anaplastic large-cell lymphoma (ALCL ALK-1 negative, n=3, 6%). Most patients had a favorable ECOG performance status (86% 0-1) and 72% were >=65 years of age. Patients had received a median of 2 prior therapies (range, 1-9). Of 9 patients assessable in phase I (n=3 at 9 mg/m2 and n=6 at 14 mg/m2), none experienced a DLT. The recommended phase II dose was 14 mg/m2 in 40 subsequently treated patients. The overall population received a median of 10 doses (range, 1-135) for a median treatment duration of 12.9 weeks (range, 0.1-184.3; 8 patients were treated for >=36 weeks). The common all-grade adverse events (AEs) were thrombocytopenia (n=49, 98%), lymphopenia (n=44, 88%), leukopenia (n=42, 84%), neutropenia (n=40, 80%), pyrexia (n=33, 66%), dysgeusia (n=31, 62%), decreased appetite (n=28, 56%), and nausea (n=27, 54%). The common grade >=3 AEs were lymphopenia (n=37, 74%), neutropenia (n=27, 54%), leukopenia (n=23, 46%), and thrombocytopenia (n=19, 38%). Of the 39 patients whose CD4+ T-cell counts were monitored, while decreased CD4+ T-cell counts (<200 uL) were observed in 82% of patients, opportunistic infection occurred only in 1 patient (3%). Among the 40 patients with PTCL (phase II), the ORR was 43% (95% CI, 27%-58%), including 10 patients (25%) with complete response (CR) or CR unconfirmed (CRu) and 7 (17%) with partial responses (PR) (Table 1). The obtained ORR was significantly higher compared with the threshold ORR of 10% (P<0.0001, one sample binomial test, H0: P<=0.1). The ORR was not different across PTCL subtypes: 44% (8/18) AITL, 41% (7/17) PTCL-NOS, and 100% (2/2) ALCL. In 17 responding patients, the median TTR was 1.8 months (range, 1.6-2.3) and median DOR was 11.1 months (95% CI, 1.6 to not reached). Median TTP was 5.6 months (95% CI, 3.3-12.9; n=40). For 2 patients with CTCL in phase I, best responses (investigator assessment) were 1 PR (9 mg/m2 cohort) and 1 stable disease (14 mg/m2 cohort). Pharmacokinetic analysis indicated a dose-proportional relationship, with no accumulation following multiple doses; results were similar to data reported for non-Japanese patients. Conclusions: Results from this phase I/II study identified a tolerable dose of romidepsin and indicated that romidepsin has an acceptable toxicity profile with clinically meaningful, efficacy in Japanese patients with R/R PTCL. The efficacy and safety data were comparable with results from other romidepsin phase II studies. Disclosures Ogura: Celltrion, Inc.: Consultancy, Honoraria; SymBio Pharmaceuticals: Consultancy, Honoraria. Maruyama:Janssen: Honoraria; Takeda: Honoraria. Tobinai:Chugai Pharma: Research Funding; Daiichi Sankyo Co., Ltd.: Consultancy; Mundipharma KK: Honoraria, Research Funding; SERVIER: Research Funding; HUYA Bioscience: Honoraria; Celgene: Research Funding; Kyowa Hakko Kirin: Research Funding; GlaxoSmithKline: Research Funding; Janssen Pharmaceuticals: Honoraria, Research Funding; Abbvie: Research Funding; Takeda: Honoraria, Research Funding; Zenyaku Kogyo: Honoraria; Eisai: Honoraria, Research Funding; Ono Pharmaceutical: Research Funding. Uchida:SymBio Pharmaceuticals: Research Funding. Hatake:Chugai: Research Funding; Meiji-Seika: Consultancy; Otsuka: Consultancy; Kyowa Kirin: Honoraria, Research Funding. Tsukasaki:Daiichi Sankyo Co., Ltd.: Consultancy; Takeda: Research Funding. Ishida:Celgene KK: Research Funding; Kyowa Hakko Kirin, Co., Ltd.: Honoraria, Research Funding; Bayer Pharma AG: Research Funding. Ishizawa:SymBio Pharmaceuticals: Research Funding. Laille:Celgene: Employment, Equity Ownership. Ro:Celgene: Employment, Equity Ownership. Tamakoshi:Celgene: Employment, Equity Ownership. Sakurai:Celgene: Employment. Ohtsu:Celgene: Employment, Equity Ownership.