A phase 2 study of idelalisib plus rituximab in treatment-naïve older patients with chronic lymphocytic leukemia
Mené sur 64 patients atteints d'une leucémie lymphocytaire chronique (âge médian : 71 ans), cet essai de phase II évalue l'efficacité, du point de vue du taux de réponse globale, et la toxicité de l'idelalisib en combinaison avec le rituximab pour un traitement de première ligne
In 64 older patients with untreated CLL or SLL, treatment with idelalisib plus rituximab was generally well tolerated. The combination produced a very high response rate (97%), including 19% complete remissions. Idelalisib is a first-in-class oral inhibitor of PI3K
δ that has shown substantial activity in patients with relapsed/refractory chronic lymphocytic leukemia (CLL). To evaluate idelalisib as initial therapy, 64 treatment-na
ïve older patients with CLL or small lymphocytic leukemia (median age: 71 years, range: 65 – 90 years) were treated with rituximab 375 mg/m2 weekly x 8 and idelalisib 150 mg bid continuously for 48 weeks. Patients completing 48 weeks without progression could continue to receive idelalisib on an extension study. The median time on treatment was 22.4 months (range: 0.8 – 45.8+). The overall response rate (ORR) was 97%, including 19% complete responses. The ORR was 100% in patients with del(17p)/TP53 mutations and 97% in those with unmutated IGHV. Progression-free survival was 83% at 36 months. The most frequent (>30%) adverse events (any grade) were diarrhea (including colitis) (64%), rash (58%), pyrexia (42%), nausea (38%), chills (36%), cough (33%), and fatigue (31%). Elevated ALT/AST was seen in 67% of patients (23% Grade ≥3). In conclusion, the combination of idelalisib and rituximab was highly active, resulting in durable disease control in treatment-naïve older patients with CLL. These results support the further development of idelalisib as initial treatment for CLL. (ClinicalTrials.gov identifier: