Cigarette makers must be worried. A tiny U.S. company has a drug that could all but destroy nicotine addiction in America and beyond, and its shares give investors a chance to profit from this potentially world-changing drug.

About 46 million Americans smoke. But most of them don’t want to. According to the Centers for Disease Control and Prevention, about 70% say they want to quit. In fact, 40% of U.S. smokers try to quit every year by abstaining for at least one day. Of course, most do not succeed. And according to public health officials, half of those who fail to quit will eventually die of smoking-related disease.

Without treatment, the chances of someone quitting on any given attempt are about 1.5%. Current remedies improve these results, but the failure rate is still daunting. Use of a nicotine replacement therapy — such as nicotine patches or gum — increases the success rate to about 3%.

Prescription drugs have been more successful — but even their results leave a lot be desired. Quit rates for GlaxoSmithKline’s (NYSE: GSK) Wellbutrin and Zyban, which reduce the severity of nicotine cravings, stand at about 15%. And the quit rate for Pfizer’s (NYSE: PFE) Chantrix — a drug that partially blocks nicotine from stimulating the brain — approaches 26%; however, this drug has received the most severe warning the U.S. Food and Drug Administration gives to medications for the serious psychological side effects it may cause.

Here’s the good news: A new drug currently in Phase III clinical trials could dramatically improve the rates at which people successfully quit smoking.

Nabi Biopharmaceuticals (NASDAQ: NABI) is a $250 million company that has a treatment that appears to beat the success rates of what’s currently on the market and which so far has caused no serious side effects. Called NicVAX, the drug not only helps people quit, it also helps prevents relapses.

NicVAX works by stimulating the immune system to produce antibodies that bind to nicotine in the bloodstream, preventing it from entering the brain. What’s more, once NicVAX is administered, the effects are irreversible for up to a year. This means that once the patient has decided to receive the treatment, there’s no going back, as the nicotine can no longer get to the brain.

The 46 million American smokers present a huge market for NicVAX. But consider this:  There are more than 1 billion smokers worldwide.

Nabi recently inked a deal with GlaxoSmithKline that gives GSK the option to obtain the exclusive worldwide license to develop, commercialize and manufacture NicVAX and related drugs. For that option, GSK is paying $40 million, and could pay up to $500 million if certain regulatory and sales milestones are reached. Nabi will also collect royalties on both NicVax and second generation drugs that GSK may develop.

The drug is currently being tested in several studies, including a Phase III study on its effectiveness in helping people quit smoking long term. The company has received a $10 million grant from the U.S. National Institute on Drug Abuse — part of the National Institute of Health — to help fund the first NicVAX Phase III trial. Nabi has said that the drug will not be ready for FDA approval before 2012.

Nabi’s latest filing dated September 2009 reported $28 million in cash in the company’s coffers and just $5 million in debt. As a small pharmaceutical company with no drugs on the market, Nabi has no significant revenue stream, but the deal inked with GSK should allow it to continue to operate through the Phase III trials.

For risk tolerant investors with the patience to wait until 2012 for Nabi’s big potential payday, the shares still offer a lot of upside as the company progresses through its Phase III clinical trials toward FDA approval and world-wide commercialization.