Biotechnology Having in April 2008 dropped a late-stage trial of the skin cancer drug, US pharmaceutical leviathan Pfizer has entered into a co-development agreement with Switzerland's Debiopharm to conduct a Phase III trial of tremelimumab (CP675,206), a fully-human anti-CTLA4 monoclonal antibody for the treatment of patients with unresectable, Stage IV melanoma. This time, a biomarker will be used to select patients considered likely to respond to tremelimumab. 8 January 2010