Positive Clinical Trial Results for Bristol-Myers Squibb’s Immunotherapy Combo
Results of a clinical trial combining Bristol-Myers Squibb’s Yervoy and Nivolumab show an exceptional improvement in tumour regression and overall survival rate for patients with advanced melanoma.
Mario Sznol of Yale University School of Medicine, reporting the results of the early-stage study, commented that “this is the first trial conducted with this combination in melanoma.” “The combination treatment nearly doubled the median overall survival found in previous studies using either agent alone,” Sznol added.
Both Yervoy and Nivolumab work by boosting the immune system. The two agents are antibodies that are members of a new class of drugs called checkpoint inhibitors, hindering the tumour cell’s ability to avoid attack by the immune system.
With tumour cells the immune system is supposed to detect and destroy the physiologic threat. However, once under attack, tumour cells can produce ‘retreat’ signals. Two of the most common of these ‘retreat’ signals are CTLA-4 and PD-1. These commands to retreat can be countermanded by Yervoy and Nivolumab, respectively.
In the clinical study, 94 patients with inoperable stage III or IV melanoma were injected with the combination of checkpoint inhibitors every three weeks.
After two years of follow-up, the response rate in this patient population was 41%, with nine patients experiencing a complete remission. The same percentage of patients had over an 80% reduction in tumour mass.
The median overall survival rate of the cohort after two years of follow-up was 79%, at an average time of 39.7 months. “Even though this is a small trial… this is an impressive two-year overall survival,” Sznol noted.
Before Yervoy, the median survival for this patient population was as little as one year, with under 25% of patients surviving as long as two years.