PURPOSE Romidepsin (depsipeptide or FK228) is a member of a new class of antineoplastic agents active in T-cell lymphoma, the histone deacetylase inhibitors. On the basis of observed responses in a phase I trial, a phase II trial of romidepsin in patients with T-cell lymphoma was initiated. PATIENTS AND METHODS The initial cohort was limited to patients with cutaneous T-cell lymphoma (CTCL), or subtypes mycosis fungoides or Sézary syndrome, who had received no more than two prior cytotoxic regimens. There were no limits on other types of therapy. Subsequently, the protocol was expanded to enroll patients who had received more than two prior cytotoxic regimens. Results Twenty-seven patients were enrolled onto the first cohort, and a total of 71 patients are included in this analysis. These patients had undergone a median of four prior treatments, and 62 patients (87%) had advanced-stage disease (stage IIB, n = 15; stage III, n= 6; or stage IV, n = 41). Toxicities included nausea, vomiting, fatigue, and transient thrombocytopenia and granulocytopenia. Pharmacokinetics were evaluated with the first administration of romidepsin. Complete responses were observed in four patients, and partial responses were observed in 20 patients for an overall response rate of 34% (95% CI, 23% to 46%). The median duration of response was 13.7 months. CONCLUSION The histone deacetylase inhibitor romidepsin has single-agent clinical activity with significant and durable responses in patients with CTCL.

Romidepsin (depsipeptide or FK228) is a histone deacetylase inhibitor, one of a new class of agents active in T-cell lymphoma. A phase 2 trial was conducted in cutaneous (CTCL) and peripheral (PTCL) T-cell lymphoma. Major and durable responses in CTCL supported the approval of romidepsin for CTCL. Forty-seven patients with PTCL of various subtypes including PTCL NOS, angioimmunoblastic, ALK-negative anaplastic large cell lymphoma, and enteropathy-associated Tcell lymphoma were enrolled. All patients had received prior therapy with a median of 3 previous treatments (range 1-11); 18 (38%) had undergone stem-cell transplant. All patients were evaluated for toxicity; 2 patients discovered to be ineligible were excluded from response assessment. Common toxicities were nausea, fatigue, and transient thrombocytopenia and granulocytopenia. Complete responses were observed in 8 and partial responses in 9 of 45 patients, for an overall response rate of 38% (95% confidence interval 24%-53%). The median du-