A discontinued Phase III trial of Roche's dalcetrapib provides the largest look at cardiovascular outcomes associated with CETP inhibition since the failure of Pfizer Inc.'s torcetrapib more than five years ago. Unfortunately, a lack of detailed data coupled with compound-specific issues means the debate over the target will likely continue until Merck & Co. Inc. produces outcomes data for its anacetrapib after 2015.

When Pfizer dropped torcetrapib in 2006 because of an increase in mortality in Phase III trials, other companies working on compounds that inhibit cholesteryl ester transfer protein (CETP) argued torcetrapib's problems were compound-specific and that different compounds bound the target in different ways (see BioCentury, Dec. 11, 2006).