PharmAthene, Inc. announced this week it has received notification from the U.S. Food and Drug Administration (FDA) that its SparVax anthrax vaccine program has again been placed on clinical hold.
SparVax is a next-generation recombinant protective anthrax vaccine being developed for pre- and postexposure protection against anthrax infection. The vaccine has previously been evaluated in three separate Phase 1 and Phase 2 clinical trials involving 770 healthy human subjects.
An earlier clinical hold was enacted in August 2012, prior to the commencement of a proposed Phase II clinical trial of SparVax, requiring PharmAthene provide additional stability data for both its engineering and GMP lots of U.S. manufactured Final Drug Product of SparVax. The hold was lifted by the FDA in May 2013.
Announcement of the clinical hold comes just weeks after PharmAthene announced it had called off a planned merger with Theraclone Sciences, maker of therapeutic antibodies for applications including pandemic or resistant influenza.
The FDA indicated that PharmAthene will receive a letter providing details of the basis for the clinical hold within thirty days. The Phase II clinical 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.