At the University of Maryland, College Park, about 35 smokers are trying to liberate themselves from nicotine by reducing the buzz it gives them, testing a “quit smoking” vaccine.

Forty percent of participants have quit so far during the ongoing study using the vaccine, NicVAX, and 9 percent quit on a placebo in preliminary studies, the largest differential ever, according to Tom Rathjem, vice president of investor relations for Nabi Biopharmaceuticals, the furthest along of three companies developing the revolutionary vaccine.