An experimental new cancer drug called MK-3475, which has shown dramatic promise for treating melanoma is also showing early potential as an effective treatment for patients with non-small cell lung cancer, the leading cause of cancer death of men and women worldwide.
The preliminary results of a phase 1B study were presented by Dr. Edward Garon, director of thoracic oncology at UCLA's Jonsson Comprehensive Cancer Center, on Tuesday October 29 at the 15th World Conference on Lung Cancer. The summit was held by the International Association for the Study of Lung Cancer, in Sydney, Australia.
The detailed interim data were on safety and activity from a cohort of 38 previously treated non-small cell lung cancer (NSCLC) patients who received MK-3475 every three weeks. The response rate of patients given MK-3475 in this cohort was 24 percent. The median overall survival rate was 51weeks. Among the patients who responded, the median response duration had not been reached at the time of this analysis, and is at least 62 weeks. Based on this data, a phase II/III trial comparing two different doses of MK-3475 to standard chemotherapy for lung cancer has begun accruing patients.
Some cancer cells can evade detection by the human immune system by expressing a protein called PD-L1 that interacts with the protein PD-1, blocking the immune system from seeing the cancer as an invader. MK-3475, an anti-PD-1 immunotherapy drug made by Merck, enables the immune system to see the cancer as a problem and allows activation of T cells (the foot soldiers of the immune system) to attack and kill the cancer cells.
The most commonly reported drug-related side effects in the study were rash (21 percent), skin itching (18 percent), fatigue (16 percent), diarrhea (13 percent) and joint pain (11 percent). Most side effects, however, were of low grade.
"These are early results, but we are very encouraged by what we've seen so far with this drug," Garon said. "Lung cancer patients who have disease that has grown after two prior therapies do not have many options and we are cautiously optimistic that this might be a treatment that improves their chances in the future."
According to the American Cancer Society, approximately 1.4 million people die from NSCLC every year, and it is the most common type of lung cancer, representing approximately 85 percent of all lung cancer diagnoses.