For High-Definition, Click
Vincristine sulfate liposome (Marqibo) is FDA approved for Philadelphia chromosome negative (Ph-) acute lymphoblastic leukemia (ALL). According to Dan Douer, MD, Marqibo’s liposomal formulation lends a better pharmacokinetic profile with more favorable outcomes compared with standard vincristine. Before Marqibo, restrictions associated with standard vincristine included combination administration and a maximum fixed dose of 2 mg.
In the pivotal phase II RALLY trial, Marqibo was studied as a single agent in 65 adult patients with Ph- ALL in second or greater relapse. The FDA recommended dose and schedule for Marqibo, which was used in the study, is 2.25 mg/m2
over 1 hour once every 7 days.
The complete remission (CR) rate was 4.6% and the rate of CR with incomplete blood count recovery (CRi) was 10.8% with Marqibo. In patients who achieved a CR or CRi, the median remission duration was 28 days and the median time to first event was 56 days.
There is an ongoing randomized trial comparing liposomal vincristine with standard vincristine for newly-diagnosed adult patients with ALL, Mark R. Litzow, MD, adds. The study plans to enroll 348 patients, with overall survival as a primary endpoint (NCT01439347).