Single-agent romidepsin induced complete and durable responses with manageable toxicity in patients with relapsed or refractory PTCL across all major PTCL subtypes, regardless of the number or type of prior therapies. Results led to US Food and Drug Administration approval of romidepsin in this indication.

BackgroundRomidepsin is a structurally unique, potent, bicyclic class 1 selective histone deacetylase inhibitor approved by the US Food and Drug Administration for the treatment of patients with cutaneous T-cell lymphoma who have received ≥ 1 prior systemic therapy and patients with peripheral T-cell lymphoma (PTCL) who have received ≥ 1 prior therapy. Approval for PTCL was based on results (n = 130; median follow-up, 13.4 months) from the pivotal study of romidepsin for the treatment of relapsed/refractory PTCL. The objective is to present updated data (median follow-up, 22.3 months) and to characterize patients who achieved long-term responses (≥ 12 months) to romidepsin.MethodsPatients 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 every 28 days for up to 6 cycles; patients with response or stable disease could continue romidepsin beyond 6 cycles. The primary endpoint was rate of confirmed/unconfirmed complete response (CR/CRu) determined by an Independent Review Committee. Secondary endpoints included objective response rate (ORR) and duration of response (DOR). For patients who achieved CR/CRu, baseline characteristics by DOR (≥ 12 vs < 12 months) were examined.ResultsThe ORR to romidepsin was 25%, including 15% with CR/CRu. The median DOR for all responders was 28 months (range, < 1-48+) and was not reached for those who achieved CR/CRu. Patients with lack of response or transient response to prior therapy achieved durable responses with romidepsin. Of the 19 patients who achieved CR/CRu, 10 had long-term (≥ 12 months) responses; none of the baseline characteristics examined—including heavy pretreatment, response to prior therapy, or advanced disease—precluded long-term responses to romidepsin. With a median progression-free survival of 29 months, patients who achieved CR/CRu for ≥ 12 months had significantly longer survival vs those with CR/CRu for < 12 months or < CR/CRu. Extended treatment and longer follow-up did not affect the reported safety profile of romidepsin.ConclusionsTreatment with romidepsin leads to highly durable responses in a subset of patients with relapsed/refractory PTCL, with responses ongoing as long as 48 months.Trial registrationNCT00426764

Acute myeloid leukemia (AML) presenting with a high leukocyte count has been associated with an increase in induction mortality and poor results in a number of other survival measures. However, the level at which an elevated leukocyte count has prognostic significance in AML remains unclear. In this report on a series of 375 adult (non-M3) AML patients undergoing induction chemotherapy at a single institution, leukocyte count analyzed as a continuous variable is shown to be a better predictor of induction death (ID) and overall survival (OS) than a leukocyte count of > or = 100 x 10(9)/L, a value characteristically associated with "hyperleukocytosis" (HL). In this patient cohort, a presenting leukocyte count of > or = 30 x 10(9)/L had high sensitivity and specificity for predicting ID, and both performance status (PS) and leukocyte count more accurately predicted for ID than age. Considering these parameters in newly-diagnosed AML patients may facilitate the development of strategies for reducing induction mortality.