September 18, 2017 — AbbVie and Genentech, a member of the Roche Group, announced that the Phase III MURANO study (NCT02005471) met its primary endpoint. The study evaluated the impact on progression-free-survival (PFS) for patients with relapsed or refractory chronic lymphocytic leukemia (CLL) between venetoclax plus rituximab (VR) compared to bendamustine plus rituximab (BR). The data showed a statistically significant improvement in the time people lived without their disease progressing when treated with VR compared to BR. No new safety signals or increase in known toxicities of venetoclax were observed with the treatment combination of venetoclax plus rituximab.
“Chronic lymphocytic leukemia is considered incurable and becomes harder to treat with each relapse,” said Sandra Horning, M.D., chief medical officer and head of Global Product Development. “This is the first study to show that Venclexta plus Rituxan can help people with this type of leukemia live significantly longer without their disease worsening compared to a standard-of-care regimen.”
We have a few other trials that suggest adding a monoclonal antibody (mAb) to venetoclax does improve outcomes compare to venetoclax alone. In contrast, there is much less certainty about the benefits of adding a mAb to ibrutinib. Also I suspect that obinutuzumab might end up being the better dancing partner for venetoclax, but all this is just my speculation. More trials are needed.
What we do know now is that VR is superior to BR in terms of PFS in relapsed/refractory patients and that is important news and has implications in how to treat those patients.
I will be more excited when we have the overall survival (OS) as that is what we patients most care about, but proving an OS advantage is a longer and less certain process that proving a PFS advantage.
Brian Koffman, MD