Evaluating the long-term outcomes of pembrolizumab versus ipilimumab for advanced melanoma

This study compared the long-term outcomes of two targeted therapies for patients with advanced melanoma. This study concluded that pembrolizumab (Keytruda) was more effective than ipilimumab (Yervoy) for these patients, with a similar rate of side effects.

Advanced melanoma is a type of skin cancer that can be difficult to treat. Targeted therapies such as pembrolizumab and ipilimumab have improved treatment outcomes for patients with melanoma. This type of treatment specifically targets cancer cells. This results in fewer side effects compared to chemotherapy.

A previous study showed that pembrolizumab was more effective than ipilimumab for treating advanced melanoma. However, this study had a short duration of only two years. Thus, the long-term safety and effectiveness of pembrolizumab for patients with advanced melanoma is unclear.

This study had 834 patients with advanced melanoma. 566 patients received pembrolizumab, and 278 patients received ipilimumab for two years. More than half of the patients in each group (65 – 66%) received these agents as first-line therapy. Patients were followed-up for five years after treatment. 

Overall, more patients in the pembrolizumab group responded to treatment compared to the ipilimumab group (42% vs. 17%). More patients in the pembrolizumab group also had no signs of cancer after treatment (14% vs. 3%). More patients in the pembrolizumab group also had tumor shrinkage (28% vs. 13%).

Patients in the pembrolizumab group survived for an average of 32.7 months compared to 15.9 months in the ipilimumab group. Patients in the pembrolizumab group survived for an average of 8.4 months without tumor growth or spread compared to 3.4 months in the ipilimumab group. At follow-up, 38.7% of patients in the pembrolizumab group were still alive compared to 31% in the ipilimumab group.

80% of patients in the pembrolizumab group and 74% of the ipilimumab group experienced side effects. The most common side effects were inflammation in the gut (2% vs. 6%) and diarrhea (2% vs. 3%). Fatigue was also reported (4 patients vs. 3 patients). 

17% of the pembrolizumab group and 20% of the ipilimumab group reported serious side effects. Similar numbers of patients in both groups (10% vs. 9%) stopped treatment due to side effects.

This study concluded that pembrolizumab was as safe but more effective than ipilimumab for patients with advanced melanoma. The authors suggest that pembrolizumab should continue to be a first-line treatment option for these patients.

This study was funded by Merck Sharp & Dohme, the manufacturer of pembrolizumab. Also, the number of patients in each treatment group was not the same, which may bias the results.

Talk to your doctor about which targeted therapy may be right for you.