According to HHS, BARDA "determined that none of the vaccine developers submitting proposals could meet the Project BioShield statutory requirements of having a product ready for licensure within 8 years. In response to this development, BARDA will modify its approach to the advanced development of a next-generation anthrax vaccine."
It is unclear why this happened, nor whether BARDA is moving away from next-generation anthrax vaccines into other anthrax therapeutics.
My suggestion to BARDA is to consider an emergency stockpile of live, attenuated vaccine. The advantages of a safe, live vaccine could include: more rapid and cheaper production, more rapid development of immunity and broader immune protection.