Umbralisib has ‘distinct’ safety profile

There were no treatment-related deaths.

The researchers said the safety profile of umbralisib was distinct from that of other PI3Kδ inhibitors, as patients in this trial had fewer occurrences of autoimmune-like toxicities, such as colitis.

“Preclinically, umbralisib has a very unique profile, selectively inhibiting both PI3Kδ and CK1ε,” said study author Owen O’Connor, MD, PhD, of Columbia Presbyterian Medical Center in New York, New York.

“The clinical results in this paper support our thesis that the differentiated preclinical profile explains the differences seen in the clinic between umbralisib and the other PI3Kδ inhibitors.”

Response

The objective response rate was 37%, with 33 patients achieving a response and 3 patients having a complete response (CR).

Sixteen CLL patients responded (80%), all with partial responses (PRs). Four DLBCL patients responded (31%), all with PRs. And 9 FL patients responded (53%), 2 with CRs.

The remaining CR occurred in a Hodgkin lymphoma patient, and this was the only response in this patient group.

One patient with marginal zone lymphoma had a PR, as did 1 patient with mantle cell lymphoma. All other patients had stable disease or progressed.

The mean duration of response was 13.4 months in the CLL patients, 6.4 months in the DLBCL patients, and 9.3 months in the FL patients.