PharmAthene, Inc. has received notification from the FDA that its SparVax rPA anthrax vaccine program has been placed on clinical hold. The Agency indicated that the company will receive a letter providing details of the basis for the clinical hold within 30 days. The Phase II study, which was expected to begin by the end of this year, has not enrolled any subjects to date and accordingly, there have been no adverse events reported. SparVax is a next-generation recombinant protective (rPA) anth...