Chiron Corp.'s last vaccine play was to pull its trivalent DTaP vaccine from registration because three similar products already were marketed. But last week CHIR found a way to monetize its DTaP investment by providing the antigens to Rhein Biotech N.V. for use in a pentavalent vaccine that can provide higher margins.

Three other diphtheria, pertussis, and tetanus vaccines are marketed by GlaxoSmithKline plc (GSK; LSE:GSK, London, U.K.); Aventis Pasteur (SWX:AVE, Strasbourg, France); and