Evaluating ipilimumab and radiation therapy for patients with high risk melanoma

The aim of this study was to check the safety and effectiveness of the combination of ipilimumab (Yervoy) and radiotherapy (RT) in patients with high-risk melanoma. The study found that ipilimumab + RT was safe and had good responses in these patients.

Melanoma is a type of skin cancer. First line therapy for melanoma usually involves surgical removal of the tumor. Some patients have a spread of the tumor to other areas (metastasis). In these patients, the tumor can reappear after surgery (recurrent melanoma). In some patients, it may not be possible to remove the tumor (unresectable melanoma). Recurrent and unresectable melanoma are high-risk diseases and do not have many treatment options.

Immune checkpoint inhibitors (ICI) and RT are possible therapies. RT uses high-energy radiation to kill cancer cells by damaging their DNA. ICIs are immunotherapies that prevent the immune system from switching off. This allows the immune system to target and kill cancer cells. Ipilimumab is an ICI.

Ipilimumab and RT have been tested as therapies for several cancers. It is not known whether a combination of ipilimumab + RT is safe for patients with high-risk melanoma.

This study included 24 patients with high-risk melanoma. Patients were split into 2 treatment groups. Group 1 included 13 patients who had surgery to remove the tumor. Then, they were given RT and ipilimumab. Group 2 (11 patients) were given RT and ipilimumab followed by surgery to remove the tumor. In all patients, ipilimumab treatment started within 3 days of starting RT. The average follow-up time for group 1 was 25.8 months and 25.3 months for group 2.  

For group 1, 69% of patients had no relapses at 12 months and 62% had no relapses after 2 years. The average time patients relapsed in group 1 was 26.7 months. 

In group 2, 64% of patients showed a response to therapy after 16 weeks. Overall, 73% of patients had no progression of the disease after 1 and 2 years. 3 patients in group 2 went on and had complete removal of the tumor after RT and ipilimumab treatment.

Most side effects of RT and ipilimumab treatment were mild. 15% in group 1 and 18% in group 2 experienced moderate side effects and no severe side effects were reported. The most common side effects were tiredness, itching and skin reactions.

This study showed that a combination of ipilimumab + RT is safe and had promising responses for patients with high-risk melanoma.

The sample size of the study was small. More patients will be needed to investigate how effective ipilimumab + RT is for the treatment of high-risk melanoma. This study was funded by Bristol-Myers Squibb, the manufacturer of ipilimumab.