The Meso Foundation is optimistic about the results of the Phase 1b trial of pembrolizumab for PD-L1-positive advanced solid tumors, which were announced at the most recent meeting of the American Association for Cancer Research (AACR).
Dr. Evan W. Alley, MD, PhD, co-director of the Penn Mesothelioma and Pleural Program, reported the results of a Phase 1b trial of pembrolizumab for PD-L1-positive advanced solid tumors at the AACR Annual Meeting on Sunday. Of the twenty-five patients with mesothelioma who were treated as part of the study, 28% experienced tumor shrinkage and another 48% had prolonged stabilization of their disease. The drug was also demonstrated to be safe, with no patients discontinuing treatment as a result of side-effects.
”These results are quite exciting, and provide further proof of principal that this class of drugs, known as checkpoint inhibitors, are effective for mesothelioma,” noted Dr. Lee M. Krug, Chair of the Board of Directors for the Meso Foundation. “Hopefully this study will encourage much larger trials in this disease.”
Pembolizumab is an antibody that blocks the inhibitory effects of PD-1, thereby boosting the immune system’s activity. In cancer, high tumor expression of PD-L1 is linked with more aggressive disease and a poorer prognosis, and PD-L1 expression was used to select patients for this study. PD-1 inhibitors have already shown great promise in melanoma, renal cell carcinoma and lung cancer, demonstrating both tumor shrinkage and durable responses. Pembrolizumab (KeytrudaTM) is FDA approved for the treatment of advanced melanoma.
Early on, the Foundation funded a companion study that we anticipate will help to define markers enabling us to personalize our approach to some of these drugs.
In May, the Meso Foundation will be hosting Dr. Alley in an interview, as part of the Meet the Mesothelioma Experts series. More information about the series is available at curemeso.org/experts.