Use of Duvelisib After Ofatumumab in Resistant CLL/SLL
Posted: Monday, April 20, 2020
According to findings from a crossover extension trial of the phase III DUO study, presented in Clinical Cancer Research, the PI3K inhibitor duvelisib may be an effective treatment for patients with relapsed or refractory chronic lymphocytic leukemia (CLL) or small lymphocytic lymphoma (SLL). Monotherapy with duvelisib, concluded Matthew S. Davids, MD, of the Dana-Farber Cancer Institute, Boston, and colleagues, provided “robust and durable” responses in patients with radiographically confirmed progressive disease after ofatumumab monotherapy in the original phase III DUO trial.
“These results confirm duvelisib as an effective, all-oral treatment option in CLL [and] SLL and support the development of further prospective studies of the drug both as a single agent and in combination regimens,” the authors noted.
The authors focused on 90 patients with relapsed or refractory CLL or SLL who demonstrated progressive disease after being treated with ofatumumab; they then crossed over to duvelisib. Patients received 25 mg of duvelisib twice daily for 28-day cycles until progressive disease, intolerance, death, or study withdrawal.
Before the crossover to duvelisib, the patients exhibited an overall response rate of 29%, a median duration of response of 10.4 months, and a median progression-free survival of 9.4 months. After crossover, 69 patients (77%) achieved a response, with a median duration of response of 14.9 months, and a median progression-free survival of 15.7 months. Similar outcomes were observed for patients with del(17p) or TP53 mutations. Moreover, 47 of 64 patients (73%) who had refractory disease prior to ofatumumab achieved a response. The most frequent any-grade and grade 3 or 4 treatment-emergent adverse events were diarrhea, neutropenia, pyrexia, cutaneous reactions, and thrombocytopenia.
Disclosure: For a full list of study authors’ disclosures, visit clincancerres.aacrjournals.org.