Study: Medical marijuana can help people with hep C
September 20, 2006
Liz Highleyman, Bay Area Reporter
Medical marijuana can help people with hepatitis C stay on treatment longer, leading to better outcomes, according to a study published in the October 2006 issue of the European Journal of Gastroenterology and Hepatology.
The standard treatment for hepatitis C virus (HCV), a combination of interferon plus ribavirin taken for six months to a year, can cause side effects such as flu-like symptoms, insomnia, nausea, loss of appetite, and depression, which drive many patients to reduce their doses or stop treatment prematurely. If left untreated, hepatitis C can lead to cirrhosis, liver cancer, and death due to liver failure.
Although the federal government claims that medical marijuana has no accepted medical uses, several studies – and ample anecdotal evidence – indicate that cannabis helps reduce nausea and increase appetite in people with AIDS.
"This study confirms what a lot of us have long understood but have had trouble documenting: that medical marijuana does in fact save lives by allowing people to stay on their medications and complete treatment," said Bruce Mirken of the Marijuana Policy Project. "It's time for the federal government to cut the crap and acknowledge that for many people, this is a safe and effective medication."
Dr. Diana Sylvestre, from the University of California at San Francisco, and colleagues studied 71 recovering drug users with hepatitis C treated at the Organization to Achieve Solutions in Substance Abuse in Oakland, where Sylvestre serves as executive director. All had been on methadone maintenance for at least three months, and about a third used marijuana while being treated for hepatitis C; according to the researchers, cannabis use during the study was "neither endorsed nor prohibited."
HCV can be transmitted through shared needles and other drug-injection equipment, and active or former drug users make up a large proportion of patients with hepatitis C. In the past, experts recommended against hepatitis C treatment for active or recent substance users, but studies have shown that such individuals can achieve good outcomes if they maintain adequate adherence.
In the OASIS study, participants were treated with an older form of interferon plus ribavirin for 24 or 48 weeks. At the end of treatment, 64 percent of cannabis users had undetectable HCV viral load, compared with 47 percent of non-users. After an additional six months of post-treatment follow-up, three times as many cannabis users achieved a sustained response compared with non-users (54 percent versus 18 percent), indicating that the marijuana users were less likely to relapse.
Most patients experienced some side effects, but the cannabis users were more likely to adhere to therapy and less likely to stop treatment early. Overall, marijuana users stayed on treatment for an average of 38 weeks, compared to 33 weeks for non-users.
"Our results suggest that modest cannabis use may offer symptomatic and virological benefit to some patients undergoing HCV treatment by helping them maintain adherence to the challenging medication regimen," the researchers concluded.
According to Mirken, this is thought to be the first published study linking medical marijuana to improved cure rates for a life-threatening illness.
Cannabis appeared to improve treatment outcomes by helping patients stay on therapy. Response rates did not improve with greater marijuana consumption; in fact, patients who used the largest amounts did not show as much benefit.
"We can't judge whether there was an antiviral effect from this particular study," Sylvestre told the Bay Area Reporter . "Patients who smoked cannabis stayed on treatment a little bit longer, and it was probably more of a side-effect management effect than an antiviral effect, but we can't rule out the latter."
Brian Klein, a founder of the Hepatitis C Action & Advocacy Coalition (who was not a participant in the OASIS study) credits medical marijuana with helping him achieve a cure with his second attempt at treatment.
"One of the main reasons my treatment succeeded was that I was able to stay on my medications," he said. "Medical marijuana allowed me to successfully treat my hepatitis C and clear the virus."
While the OASIS results appear promising, there are concerns about the safety of long-term marijuana use by people with chronic hepatitis C. Some components of the cannabis plant may suppress immune function, and, as reported last year in the July 2005 issue of Hepatology , French researchers found that untreated hepatitis C patients who smoked cannabis daily were more likely to have severe liver damage than occasional users and non-users.
"We were looking at treatment outcomes, and they were looking at people who smoked lots of marijuana over the long term," said Sylvestre. "Our study suggests that using modest amounts of cannabis for side effects management is not harmful."
However, the researchers acknowledged in their report, "We cannot rule out the possibility that detrimental biological or immunological mechanisms may be relevant at higher levels of consumption. Obviously, further study is needed."
Unfortunately, federal drug laws make it difficult to carry out well-designed research on the medical uses of cannabis. Efforts by advocates to encourage the Food and Drug Administration to approve controlled studies have been repeatedly rebuffed.
In an editorial accompanying the OASIS journal report, six hepatitis experts from Canada and Germany suggested that medical marijuana may be especially beneficial for individuals on methadone maintenance, since methadone itself can cause some of the same side effects as interferon.
"Overall, cannabis use may thus even offer dual benefits, in facilitating adherence to both methadone maintenance therapy and HCV treatment in the HCV-infected drug user, and thus contribute to public health benefits related to both these interventions," they wrote.
Until results from further research are available, they recommended that "existing barriers to cannabis use [should be] removed for drug users undergoing HCV treatment."