Final results from the Phase 2 PRIMO trial showed that duvelisib (Copiktra) produced strong responses in patients with relapsed or refractory peripheral T-cell lymphoma (PTCL). The treatment achieved an overall response rate of 48%, higher than the 25% to 30% typically seen with many single-agent therapies. Complete responses were reported in 33.3% of patients.
Results were especially promising in patients with angioimmunoblastic T-cell lymphoma (AITL). In this subgroup, the response rate reached 62.2%, with complete responses in more than half of patients. Median overall survival was 18.1 months in the AITL group, compared with 12.4 months in the overall study population.
Duvelisib works by blocking PI3K-δ and PI3K-γ signaling pathways that help cancer cells survive. Severe side effects occurred in 74% of patients, and one-third stopped treatment because of toxicity, mainly liver problems and diarrhea. Researchers used a higher starting dose followed by lower maintenance dosing to balance effectiveness and safety.