Idelalisib: Additional Phase III data

Additional data from the double-blind, international Phase III Study 116 in 220 previously treated CLL patients showed that twice-daily 150 mg oral idelalisib plus rituximab led to a 24-week PFS rate of 93% vs. 46% for placebo plus rituximab (p<0.0001). In October, Study 116 was stopped early on the recommendation of an independent DMC after a predefined interim analysis at 50% of the planned total number of 119 events of CLL progression or death showed that idelalisib plus rituximab met the primary endpoint of improving median PFS vs. placebo plus rituximab (not yet reached vs. 5.5 months, p<0.0001) (see BioCentury, Oct. 14). A pre-specified subgroup analysis showed that idelalisib plus rituximab also improved PFS in patients with a deletion of chromosome 17 (del17p) or mutation in the tumor protein p53 ( TP53; p53) gene (HR=0.12).

Idelalisib plus rituximab also met the secondary endpoints of improving ORR (81% vs. 13%, p<0.0001) and OS (p=0.018) vs. placebo plus rituximab. Additionally, a significantly greater proportion of patients receiving idelalisib plus rituximab achieved a >=50% reduction in lymph nodes vs. placebo plus rituximab (93% vs. 4%, p<0.0001). The trial enrolled patients with previously treated recurrent CLL who had measurable lymphadenopathy with disease progression less than 24 months after completing prior therapy and who were ineligible for cytotoxic therapy. Data were presented at the American Society of Hematology meeting in New Orleans. Patients in the trial were eligible to be enrolled in the Study 117 extension of Study 116. ...