SEP 16, 2020

Does Discontinuation of Immunotherapy Effect Final Results in Metastatic Melanoma?

WRITTEN BY: Jasper Cantrell

The last decade has seen the emergence of several new therapies against cancer. For melanoma, checkpoint inhibitors have become the go-to treatments or “first-line therapies.”

The inhibitors in question are pembrolizumab, nivolumab, and the combination therapy ipilimumab/nivolumab. All three have comparable results and are considered the standard treatments for melanoma. Unfortunately, instances of melanoma are on the rise, and survival rates for metastatic melanoma are a quarter of what they are for local melanomas.

A new study from McGill University in Canada wanted to examine how discontinuation of first-line therapy for metastatic melanoma patients affected the final results. The team hypothesized that clinical trials don’t represent real-world patients due to patient criteria often found in trials. This new study would remedy that by using real-world patient data to reveal useful information on how discontinuation of treatment affected results.

They utilized several databases to gather data from 876 patients with metastatic melanoma. They found that pembrolizumab was the most common treatment, followed by nivolumab and the ipilimumab/nivolumab combination therapy. All three have relatively similar effectiveness, but pembrolizumab may offer slightly better results, making it more popular for doctors and patients.

The team also noted that pembrolizumab had the longest therapy time, with an average of 12 months before the treatment was halted. Combination therapy had the earliest discontinuation time, which contrasted with the generally better responses it gets. Combination therapy was also more likely to end with no progression onto a second-line therapy than the monotherapies, which tended to move onto second-line therapy. Disease progression and immune-related issues were the most common reasons for discontinuation.

This study identified pembrolizumab as the most common and most stable as far as therapy length goes. A determination of sufficient therapy length couldn’t be determined with the data on hand, but several important factors concerning treatment were identified.

The study concludes, “In conclusion, these real-world data demonstrated that a large proportion of patients discontinued initial therapy with pembrolizumab, nivolumab, or nivolumab/ipilimumab before two years and that difference in therapy discontinuation was very small or not detectable between patients initiating those therapies, but with trends for lower discontinuation with pembrolizumab.”

Sources: Nature Scientific Reports, Mayo Clinic