Acambis and Bavarian Nordic Vie for Smallpox Vaccine Contract

The US Department of Health and Human Services issued a request for proposals (RFP) on Aug. 15 to acquire 20 million doses (in single-dose vials) of modified vaccinia Ankara (MVA) vaccine, a highly attenuated live smallpox vaccine. The two companies expected to compete for the contract are Acambis plc (Cambridge, UK, www.acambis.com) and Bavarian Nordic A/S (Copenhagen, www.bavarian-nordic.com). Both have conducted early clinical trials on MVA vaccines under contracts with the US National Institute of Allergy and Infectious Diseases.

MVA is based on a strain of the smallpox vaccine that does not replicate effectively in human cells. This modified form is being developed for use in individuals with compromised immune systems or atopic dermatitis (eczema) who cannot take the standard smallpox vaccine. Animal studies and Phase I and II clinical trials have shown MVA to be safe and immunogenic. Although FDA has not granted marketing approval to these investigational vaccines, the Centers for Disease Control and Prevention could authorize their emergency use in the event of a bioterrorist attack.

Manufacturing capacity is a key competitive element in the bidding process. Bavarian Nordic began pilot production of its MVA vaccine, “Imvamune,” at its plant in Kvistgård, Denmark in July. The company says it will begin GMP manufacturing there in September, with an initial capacity of approximately 40–60 million doses per year that can be expanded to 180 million doses per year. In the meantime, Bavarian Nordic has produced its clinical trials materials at a plant in Berlin, which it acquired from Schering AG in May 2003. Bavarian Nordic also has a global commercial manufacturing and marketing agreement with GlaxoSmithKline (GSK, Uxbridge, UK, www.gsk.com), which includes back-up manufacturing capacity for government contracts.

Acambis has partnered with Baxter International, Inc. (Deerfield, IL, www.baxter.com) for process development and manufacturing services. “To us, manufacturing is a real strength, because we have Baxter in place, who really know what they are doing in this area,” says Lindsay Wright, vice-president of communications for Acambis. Baxter declined to say which manufacturing sites it would use or to talk specifically about capacity. Wright would say, however, that Acambis previously has supplied the US national stockpile with more than 180 million doses of its full-strength smallpox vaccine, “Acam2000,” which replaced the Dryvax vaccine used until the disease was eradicated in 1980.

While noting that the bidding is highly competitive, Wright acknowledged that multiple contracts might be issued to avoid government reliance on a single source of a strategic vaccine. Such concerns were raised when the US government first awarded a single contract for the supply of anthrax vaccine to VaxGen in Nov. 2004.

Under the MVA vaccine contract, the Department of Health and Human Services would buy a minimum of 20 million doses over two years, with an option to buy an additional 60 million doses. The US will also pay the contract winners to maintain CGMP manufacturing capability, referred to as a “warm-base."

–Laura Bush