SIGA Technologies has announced that is bowing out of its planned merger with PharmAthene. The company cited several factors, including positive trial data, a $27 million in grants for smallpox and arenavirus programs, and a $16.5 million NIH grant, that led to its decision to abandon the deal. "SIGA is excited about its future and committed to the development and successful completion of its lead product candidate, SIGA-246, a smallpox antiviral treatment, as well as its other anti-viral and anti-infective programs," Donald Drapkin, Chairman of the Board of SIGA, stated in a press release. Back in July SIGA and PharmAthene said they would merge to create a single company concentrating on developing new biodefense products. Release