LANSING, Mich. (AP) – The nation’s sole maker of the anthrax vaccine said Monday that it is a step closer to beginning shipments to the Pentagon.

A few hurdles remain before BioPort Corp. can actually ship the vaccine, possibly by later this month.

BioPort said it received a Dec. 27 letter from the Food and Drug Administration clearing it to begin shipping the vaccine made at its Lansing laboratory, provided a laboratory in Washington state that puts the vaccine into vials also receives FDA approval.

The vaccine already manufactured by BioPort also must pass FDA inspection before shipment.

If BioPort is allowed to resume shipments, the Pentagon will be able to resume inoculating millions of military personnel. The vaccinations drew virtually to a halt after Pentagon supplies of the vaccine ran low.

BioPort bought a Michigan state-owned anthrax-vaccine manufacturing operation in 1998. But the company was not allowed to supply the vaccine to the Pentagon because the laboratory failed two FDA inspections after a renovation.

In its letter, the FDA granted the lab final approval and said the company has made or is in the process of making the seven production-related changes requested by inspectors during their visit last month.

FDA inspectors last week wrapped up a four-day inspection of Hollister-Stier Laboratories in Spokane, Wash., where the vaccine manufactured by BioPort is put into vials.

FDA inspectors cited six production-related changes they want Hollister-Stier to make before winning approval. Three of the changes involve record-keeping data, and all appear to be resolvable, according to FDA and BioPort officials.