Ablynx has discontinued clinical development of its most advanced nanobody citing market reasons. The Ghent, Belgium–based biotech announced in November that ALX-0081—a bivalent nanobody designed to prevent unwanted thrombus formation—did not significantly reduce the number of bleeding events in a phase 2 study treating acute coronary syndrome (ACS) patients compared with approved antithrombic ReoPro (abciximab). ALX-0081 interferes with von Willebrand factor, which acts early in the coagulation cascade. The decision to cut trials short was financial, says Ablynx's CEO Edwin Moses. “The antithrombotics market has become more competitive. Unless you have a standout advantage, it's going to be an uphill commercial battle.” The trial wasn't a total waste, as the company plans to channel its efforts into developing the nanobody to treat thrombotic thrombocytopenic purpura (TTP), a rare blood clotting disorder. “It's a sensible decision,” comments Mick Cooper, a healthcare analyst at London-based Edison Investment Research. The company will apply the data from the ACS trial to TTP clinical trials, says Moses. The company has two other nanobody drug candidates, ATN-103 and ALX-0061 to treat rheumatoid arthritis, in phase 2. Phase 1 data for ALX-0061, also announced in November, were “very impressive,” says Cooper. “The company is doing a very good job of running its clinical programs.”