RESUMO
Richter transformation (RT) is a rare complication of chronic lymphocytic leukemia (CLL) that has dismal outcomes. Upregulation of PD-1/PD-L1 drives immunological evasion in patients with RT. We hypothesized that combining nivolumab, a PD-1 blocking antibody, with the BTK inhibitor (BTKi) ibrutinib could potentiate tumor-cell killing. We conducted an investigator-initiated phase 2 clinical trial to assess the efficacy of combined nivolumab and ibrutinib in patients with diffuse large B-cell lymphoma (DLBCL) RT and CLL. Patients included were ≥18 years of age with adequate hepatic and renal function. Patients received nivolumab every 2 weeks of a 4-week cycle for a maximum of 24 cycles. A standard dose ibrutinib was initiated from cycle 2 onward and continued daily until progression. For patients who were already on ibrutinib at the time of study entry, the same was continued while nivolumab was initiated. A total of 24 patients with RT with a median age of 64.5 years (range, 47-88) were enrolled. Ten patients (42%) had received prior treatment for RT and 13 patients (54%) had received a prior BTKi. A total of 10 patients (42%) responded with a median duration of response of 15 months. The median overall survival was 13 months. Four of 24 (17%) patients had checkpoint inhibition-related immunological toxicities. In the CLL cohort, 10 patients were enrolled, of whom 3 patients converted from partial to complete remission; 1 patient had a grade 2 immunological toxicity. Combined nivolumab and ibrutinib is an active regimen for patients with DLBCL RT with an overall response rate of 42%. Given the limited treatment options for patients with RT, checkpoint inhibition provides a potential therapeutic option. This trial is registered at www.clinicaltrials.gov as #NCT02420912.
Assuntos
Leucemia Linfocítica Crônica de Células B , Linfoma Difuso de Grandes Células B , Humanos , Pessoa de Meia-Idade , Idoso , Idoso de 80 Anos ou mais , Nivolumabe/uso terapêutico , Receptor de Morte Celular Programada 1 , Linfócitos B/patologia , Linfoma Difuso de Grandes Células B/tratamento farmacológico , Linfoma Difuso de Grandes Células B/patologiaRESUMO
Chemoimmunotherapy with combined fludarabine, cyclophosphamide and rituximab (FCR) has been an effective treatment for patients with chronic lymphocytic leukemia (CLL). We initiated a phase II trial for previously untreated patients with CLL with mutated IGHV and absence of del(17p)/TP53 mutation. Patients received ibrutinib, fludarabine, cyclophosphamide, and obinutuzumab (iFCG) for three cycles. Patients who achieved complete remission (CR)/CR with incomplete count recvoery (CRi) with marrow undetectable measurable residual disease (U-MRD) received additional nine cycles of ibrutinib with three cycles of obinutuzumab; all others received nine additional cycles of ibrutinib and obinutuzumab. Patients in marrow U-MRD remission after cycle 12 discontinued all treatment, including ibrutinib. Forty-five patients were treated. The median follow-up is 41.3 months. Among the total 45 treated patients, after three cycles, 38% achieved CR/CRi and 87% achieved marrow U-MRD. After cycle 12, the corresponding numbers were 67% and 91%, respectively. Overall, 44/45 (98%) patients achieved marrow U-MRD as best response. No patient had CLL progression. The 3-year progression-free survival (PFS) and overall survival (OS) were 98% and 98%, respectively. Per trial design, all patients who completed cycle 12 discontinued ibrutinib, providing for a time-limited therapy. Grade 3-4 neutropenia and thrombocytopenia occurred in 58% and 40% patients, respectively. The iFCG regimen with only 3 cycles of chemotherapy is an effective, time-limited regimen for patients with CLL with mutated IGHV and without del(17p)/TP53 mutation.