Clinically Significant Responses Achieved with Romidepsin in Treatment-Refractory Cutaneous T-Cell Lymphoma: Final Results from a Phase 2B, International, Multicenter, Registration Study

Background : Responses to romidepsin, a novel pan-HDAC inhibitor, have been observed in patients (pts) with cutaneous T-cell Lymphoma (CTCL). This Phase 2B, singlearm, open-label registration study enrolled pts with CTCL (Stages IB–IVA) at 33 European and US sites. Pts with histologically confirmed CTCL who failed ≥1 prior systemic therapy, had adequate organ function, and ECOG PS 0 or 1 were eligible. Exclusions included significant cardiovascular abnormality or treatment with QTc-prolonging or CYP3A4-inhibiting drugs. Pts received romidepsin 14 mg/m 2 as a 4-hr IV infusion on days 1, 8, and 15 every 28 days for up to 6 cycles (extended for stable disease or response). Aim : The primary endpoint was the response rate among evaluable pts, measured by a combination of a weighted scoring instrument to determine skin involvement (SWAT), imaging, and circulating Sezary cells (as applicable). Results : 96 pts were enrolled and received romidepsin (as-treated); 72 (75%) were evaluable (≥2 cycles) for efficacy. Enrollment is complete, 4 pts with confirmed PR continue to receive romidepsin on extended treatment, 5 pts off-treatment are being followed. Mean age of all pts was 57±12 yrs, and median time since diagnosis was 3 yrs (range 500 msec. Conclusions : This study shows clinical benefit associated with romidepsin use in treatment-refractory CTCL, with pts achieving durable response and relief from pruritus. Toxicities associated with romidepsin were tolerable and manageable.