Both a nonadjuvanted as well as an adjuvanted swine flu vaccine currently in clinical trials spurred a robust immune response after a single dose, according to the NIH and a preliminary report in the New England Journal of Medicine, suggesting that inoculation campaigns in the U.S. may not have to require the traditional double-dose in order to protect someone. The nonadjuvanted vaccine is being developed by CSL in Australia while Novartis is working on the adjuvanted jab. Both are on track for near-term approvals.
Dosage is a key issue for manufacturers as well as governments the world over preparing for mass vaccination campaigns to protect people from a second wave of swine flu. Novartis vaccine chief Rino Rappuoli recently noted to me that the company has been developing adjuvanted vaccines in Europe for years, only turning to the U.S. relatively recently. And that has left U.S. health officials focused on the need for a booster shot in order to assure immunity. But with the worldwide supply likely to fall well short of demand, a single-shot approach would cover a far larger segment of the population.
The University of Washington's Kathleen Neuzil notes in an accompanying editorial that while children may need a second shot, the development of a shortage may prevent the government from holding any vaccine in reserve for a second jab.