Evaluating the effectiveness and safety of sequential administration of high dose aldesleukin and ipilimumab in patients with metastatic melanoma.

This study evaluated the effectiveness and safety of sequential administration of high dose aldesleukin (Interleukin-2; Proleukin) and ipilimumab (Yervoy) in patients with metastatic melanoma. The data showed that high dose aldesleukin and ipilimumab were effective and safe when administered sequentially in these patients.

Immunotherapy uses the body’s own immune system to fight against cancer cells. Recombinant Interleukin-2 (rIL-2), also known as aldesleukin is an immunotherapy treatment for people with advanced and metastatic melanoma. It functions by activating cells involved in fighting disease and infection and by preventing cancer cell growth. Ipilimumab (IPI) is also an immunotherapy that works by inhibiting (blocking) CTLA-4, an important protein in the immune system. This inhibition triggers the immune system to attack tumor cells and kill them.

Both high dose rIL-2 and IPI have shown to be effective in metastatic melanoma. However, whether sequential administration of high dose rIL-2 and IPI is safe and effective for the treatment of patients with metastatic melanoma is not known.

This study involved a total of 29 patients with metastatic melanoma. Patients were randomly assigned to receive either four cycles of high dose rIL-2 followed by four doses of IPI (group 1; 13 patients) or the reverse, meaning four doses of IPI followed by four cycles of high dose rIL2 (group 2; 16 patients). The average follow-up period was 10.1 months. 

3 patient populations were identified for further analysis. Group A included 29 patients who received the entire planned treatment with each drug (rIL-2 and IPI). Group B included 18 patients who received at least 50% of the planned treatment with each drug (rIL-2 and IPI). Group C included 28 patients who received at least one dose of either drug (rIL-2 or IPI).

For patients in group A, the 1-year overall survival (OS) rate was 75%. The OS rate was 73% for treatment group 1 and 75% for treatment group 2.

For patients in group B, the 1-year OS rate was 87%. Overall, 50% of the patients responded to treatment. The complete response (complete disappearance of cancer) rate was 17% and the partial response (partial disappearance of cancer) rate was 33%.  

For patients in group B, the 1-year survival rate without cancer worsening was 68%. The survival rate without cancer worsening was 58% for treatment group 1 and 80% for treatment group 2. Response lasted for an average of 6.8 months. 

A similar number of patients experienced side effects in both treatment groups. The most common side effects were diarrhea, low platelet cell counts, and low blood pressure.

This study concluded that high dose rIL-2 and IPI were effective and safe when administered sequentially in patients with metastatic melanoma.

This study was sponsored by Prometheus Laboratories Inc, the manufacturers of rIL-2. The sample size was very small and the follow-up time was very short.