Then former Pfizer colleagues told him about a new drug, tremelimumab, in early trials.
FORBES: Targeting Melanoma
2.
Pfizer's drug tremelimumab and Bristol-Myers Squibb's ipilimumab are antibodies to a protein called CTLA-4 (cytotoxic T-lymphocyte antigen-4) that acts as an emergency brake to prevent killer T cells from attacking healthy tissue.