The role of ipilimumab after anti-PD-1 treatment: two case reports and a literature review

Metastatic melanoma has been historically associated with a poor prognosis; however, the therapeutic landscape has experimented and impressive change in the last years due to rapid advances in the immunotherapy field. The first immunotherapy treatment for metastatic melanoma was ipilimumab (anti-CTLA-4), which showed a significant improvement of overall survival compared to chemotherapy. However, in 2015 anti-PD-1 pembrolizumab shown an improved overall survival, progression-free survival and response rate compared to ipilimumab with either a better toxicity profile. Moreover, other immunotherapy combinations and target therapies, such as BRAF and MEK inhibitors combinations, have shown better outcomes than ipilimumab. Thus, ipilimumab seems to have no role in frontline metastatic melanoma treatment and even their role in second line is being less frequent due to clinical efficacy of those other treatments. Actually, the role of ipilimumab in second line after anti-PD-1 progression is not clear although there is clinical evidence for its use. Here, we report two cases of treatment response with ipilimumab in second line setting after receiving anti-PD-1 combination. So that, ipilimumab may have a role after progression to an anti-PD-1 treatment.