Gilead stops phase 3 leukemia trials early due to patient benefit

Gilead Sciences has stopped its phase 3 leukemia drug clinical trial earlier than planned after an independent Data Monitoring Committee (DMC) found the drug to be effective against the blood cell cancer.

The trial was evaluating idelalisib in previously-treated chronic lymphocytic leukemia (CLL) patients who are not fit for chemotherapy.

The DMC recommendation is based on a predefined interim analysis that showed highly statistically significant efficacy for the primary endpoint of progression-free survival in patients receiving idelalisib plus rituximab compared to those receiving rituximab alone.

Gilead has informed the US FDA of the plan to end the study and will engage with the FDA regarding a regulatory filing in CLL.

"Given the significant unmet medical need in CLL, particularly in this population of patients who are not fit for chemotherapy, we are pleased that idelalisib has shown a clinically meaningful benefit for patients. This is the first Phase 3 study to report positive results for a new class of targeted therapies that inhibit B-cell receptor signaling as a major component of their mechanism of action, an important area of focus in the development of chemotherapy-free regimens in CLL and other B-cell malignancies. We extend thanks to the investigative sites and to the other research collaborators participating in this study, as well as to the patients who volunteered, and we look forward to sharing these data with the hematology community."

Norbert W. Bischofberger, PhD, Gilead's Executive Vice President, Research and Development and Chief Scientific Officer.

A new drug application (NDA) for idelalisib was submitted for refractory indolent non-Hodgkin's lymphoma (iNHL) in September 2013. Gilead has also announced plans to file for regulatory approval of idelalisib in the European Union later this year.

Leukemia is a cancer of the white blood cells and bone marrow. There are four main types of leukaemia: acute myeloid (AML), acute lymphoblastic (ALL), chronic myeloid (CML) and chronic lymphocytic (CLL). These four types account for 85% of all leukemia cases (the remainder are compromised of a large number of uncommon subtypes). Worldwide, around 350,000 people were diagnosed with leukaemia in 2008, according to Cancer Research UK. In 2010, 8,257 people in the UK were diagnosed with leukaemia.