Combo improves ORR, PFS in relapsed/refractory CLL

In the combination arm, 3 patients (9%) had a complete response (CR), 1 patient had a CR with incomplete marrow recovery, and 19 (59%) had a partial response.

In the control arm, 1 patient (3%) had a CR and 12 (36%) had a partial response.

The median PFS was 15.9 months in the combination arm and 10.2 months in the control arm (P=0.0192).

The median overall survival was not reached in either arm. After 2 years of follow-up, there were no deaths in the combination arm and 3 deaths in the control arm.

Safety

Ninety-one percent of patients in the combination arm and 100% of those in the control arm experienced an AE. Serious AEs occurred in 31% and 45%, respectively.

Severe neutropenia was more frequent in the combination arm than the control arm (56% vs 39%), as was severe thrombocytopenia (19% vs 15%).

However, there were fewer grade 3/4 infections in the combination arm than the control arm (13% vs 27%). And 2 patients in the control arm had febrile neutropenia, but there were no cases in the combination arm.

“These latest data show the combination of otlertuzumab and bendamustine is well tolerated and significantly increases the response rate and PFS in patients with relapsed or refractory CLL,” said Scott Stromatt, MD, study director and chief medical officer for Aptevo.

“Consequently, we are now exploring the utility of otlertuzumab in combination with additional CLL therapies to evaluate clinical benefit in distinct CLL patient subgroups.”