Further evidence of Revlimid’s (lenalidomide, Celgene) potential utility as maintenance therapy in multiple myeloma has emerged with the publication of initial data from a Phase III trial sponsored by the US National Cancer Institute (NCI).

The study (CALGB-100104), led by the Cancer and Leukemia Group B (GALGB) in collaboration with the Eastern Cooperative Oncology Group and the Blood and Marrow Transplant Clinical Trials Network, was the first randomised Phase III trial to demonstrate a clinical benefit with Revlimid therapy following stem-cell transplantation for multiple myeloma.

It showed a 58% reduction in the risk of disease progression on Revlimid compared with placebo. The trial has not yet produced any evidence of an overall survival benefit, the NCI noted. According to Reuters, though, the disease progression outcome pushed Celgene’s shares up by more than 7% in pre-market trading.

Revlimid is already widely approved in combination with dexamethasone as a multiple myeloma treatment for patients who have already received at least one prior therapy. Analysts have predicted a substantial boost to sales if the drug is approved as first-line therapy and can demonstrate benefit in the maintenance setting.

CALGB-100104 was stopped early after the data and safety monitoring committee determined that the trial had met its primary endpoint of a statistically significant improvement in time to disease progression. The study involved 568 patients with multiple myeloma enrolled between December 2004 and July 2009.

All of the patients were treated with autologous blood stem-cell transplantation following a high dose of melphalan, a drug commonly used for multiple myeloma. Of this cohort, 460 patients with adequate organ function and no evidence of progressive disease were randomised between 90 and 100 days after the transplant procedure to either Revlimid or placebo. Therapy continued until the patients showed evidence of progressive disease.

Among the patients given placebo, half saw their myeloma progress within an estimated 778 days, the NCI reported. By contrast, a median time to progression could not be defined for patients on Revlimid, as fewer than half of them experienced disease progression.

Detailed results from the study will be presented “in a peer-reviewed setting” in 2010, Celgene said.

At the recent 51st American Society of Hematology annual meeting in New Orleans, the company presented favourable results on progression-free survival (PFS) from MM-0115, a Phase III trial in which older patients newly diagnosed with multiple myeloma were given Revlimid in combination with melphalan and prednisone, followed by Revlimid alone (MPR-R); Revlimid in combination with melphalan/prednisone, followed by placebo (MPR); or placebo, melphalan and prednisone, followed by placebo (MP).

Preliminary data showed that patients treated with MPR-R had a 50% reduction in risk of disease progression compared with MP. However, there was no significant difference in median PFS between the MP and the MPR arms, prompting some analysts to question the viability of Revlimid as a front-line therapy.