Use of monoclonal anti-CTLA4 antibodies represents a new promising strategy to 
block the activation of immunosuppressive CTLA-4 and thus induce tumour 
regression. This review is mainly focused on the report of existing data on the 
clinical use of Ipilimumab (formerly MDX-010) in the treatment of metastatic 
melanoma. Several phase I and II trials have been conducted to evaluate safety 
and efficacy of this form of immunotherapy either alone or in combination with 
vaccines or chemotherapy in patients with stage III or stage IV melanoma. 
Results from these studies are presented, patented and discussed. The mechanism 
of ipilimumab action may take time to induce an anti-tumour immune response and 
thus it is recommended that ipilimumab therapy should be carried out for at 
least 12 weeks, even in the presence of early progressive disease. Objective 
response of around 15% has been reported in patients treated with ipilimumab. 
However, ipilimumab-mediated objective response and stable disease tend to be 
durable. The therapy with ipilimumab is associated with different side effects 
classified as immune-related adverse events (IRAEs). The most common IRAEs are 
enterocolitis and dermatitis. Majority of IRAEs disappear with the 
discontinuation of ipilimumab anti-CTLA-4 therapy. Several phase II/III trials 
are ongoing to evaluate ipilimumab alone or in combination with other 
therapeutic modalities. Results from these trials are awaited.