Celgene has decided to terminate the Phase III ORIGIN trial of Revlimid (lenalidomide) due to imbalance in the number of deaths in lenalidomide patient-group compared to patients treated with chlorambucil.

The open-label, ORIGIN study was put on hold by the US FDA on 12 July and asked to discontinue lenalidomide treatment.

The action will be officially communicated to all clinical investigators, who are conducting the ongoing chronic lymphocytic leukaemia studies using the agent.

Though no specific causality for the imbalance has been identified to date, 34 deaths out of 210 patients in the lenalidomide arm versus 18 deaths out of 211 patients in the chlorambucil arm have occurred.

A total of 450 previously untreated elderly patients with B-cell chronic lymphocytic leukaemia were enrolled in the trial, with a majority of them suffering from multiple comorbidities, such as diabetes, congestive heart failure, renal impairment and elevated bilirubin count.

The study was designed to evaluate the efficacy and safety profile of lenalidomide against chlorambucil as single agent in patients aged more than or equal to 65 years.

All other chronic lymphocytic leukaemia trials with lenalidomide, sponsored by Celgene, will continue as per their respective protocols.

Revlimid is not approved as a treatment for patients with chronic lymphocytic leukemia, according to the company.

Image: Peripheral blood smear showing chronic lymphoid leukemia cells. Photo: courtesy of Mary Ann Thompson.