Trenton, New Jersey - Multiple studies presented at last month’s American Association for Cancer Research conference in Philadelphia show promising results in favor of a new cancer immunotherapy drug, Merck & Co.’s Keytruda, in the treatment of mesothelioma, lung cancer, and melanoma.
This new wave of drugs works to support the immune system by attacking and ultimately killing cancer cells. Specifically, Keytruda targets a protein called Programmed death-ligand 1, or PD-L1, which is speculated to be an immune system suppressor.
One study comparing the efficacy of Keytruda to Yervoy, Bristol-Myers Squibb’s market contender, showed 33 percent of melanoma patients on Keytruda with shrinking or disappearing tumors, versus 12 percent of Yervoy patients, who also experienced serious side effects earlier and more often. In 495 patients with advanced non-small cell lung cancer, equally encouraging results were found with a high percentage of patients responding positively to the treatment, with shrinking or disappearing tumors and extended survival rates.
Dr. Hossein Borghaei, a lung cancer and mesothelioma specialist at Fox Chase Cancer Center in Philadelphia, noted that these outcomes, including the fact that Keytruda extended survival about the same as regular chemotherapy, are “great news.”
Keytruda and Mesothelioma
For mesothelioma specifically, a rare and fatal cancer caused by exposure to asbestos, Borghaei stated that, “It’s very encouraging to have the kind of results that the investigators are reporting…[especially] for an early-stage investigation into this terrible disease.”
In a study of 25 mesothelioma patients who had tumors with the PD-L1 protein, for which chemotherapy proved unsuccessful, 76 percent saw improvements after an average of 5½ months of treatment. Tumors shrank in 28 percent of patients while tumors stopped growing completely in another 48 percent. Compared to chemotherapy, the side effects of Keytruda were also more tolerable.