Studies indicate that a nicotine vaccine may be safe and somewhat effective in preventing fetal damage from maternal smoking, according to the National Institute on Drug Abuse (NIDA).

Tests of NicVAX show that the vaccine, which blocks the entry of nicotine into the brain, also prevents nicotine from crossing the placenta and entering the body of a developing fetus. "We desperately need medications that can help women quit smoking during pregnancy, medications that are both effective and do not themselves harm the fetus. This study supports the potential use of immunization," said researcher Paul Pentel of the University of Minnesota Medical School.

However, researchers are unsure if the vaccine would fully protect the fetus if the mother continued to smoke. "I'm not sure that the effect would be large enough," said Pentel. "When nicotine is administered chronically in a way that approximates daily smoking, its long-term accumulation in the fetal brain looks the same in vaccinated and unvaccinated animals."

NicVAX is being developed by Nabi Biopharmaceuticals with support from NIDA. The study appears in the June 1, 2007 issue of the journal Biochemical Pharmacology.