Many a biotech company has seen a compound make it all the way to Phase III only to fail to meet the primary end point. But to the dismay of ATIII LLC, a joint venture between Genzyme Transgenics Corp. and Genzyme General, positive Phase III data were not enough to win FDA approval of its recombinant human antithrombin III compound to treat heparin-resistant patients undergoing cardiopulmonary bypass surgery.

Faced with small market potential combined with the costs of having to meet FDA demands for additional data, the venture last week decided to terminate development.