Novel Drug Tested Against Hepatitis C

March 28, 2013

News Review from Harvard Medical School – Novel Drug Tested Against Hepatitis C

An experimental drug may one day help to treat hepatitis C, according to the results of a small study. The study included 36 people with hepatitis C. They were randomly assigned to five weekly injections of the drug miravirsen, or placebo. Three doses of miravirsen were tested. The drug reduced the amount of hepatitis C virus in people's blood. Higher doses caused greater reductions. The effects lasted for several months. There were no signs of drug resistance. Miravirsen is a new type of drug, called an RNA interference drug. The study was published in the New England Journal of Medicine. National Public Radio wrote about it online.

By Robert H. Shmerling, M.D.
Harvard Medical School

What Is the Doctor's Reaction?

Hepatitis C is a virus that infects the liver. It has been in the news a lot lately because it is:

• Common—About 1.5% of the US population and 3% of the world's population is infected.
• Frequently silent—Because many (or, perhaps, most) people infected with hepatitis C don't know it, new recommendations suggest more widespread screening.
• Potentially serious—Hepatitis C may cause cirrhosis and liver failure. It's also a major risk factor for liver cancer.
• Poorly treated—Current treatments are not uniformly effective and serious side effects are common.

For all of these reasons, news about an advance in the treatment of hepatitis C could be important. And that's my sense about a new study published in the New England Journal of Medicine.

In this latest trial, researchers used a drug that works in a novel way: It blocks microRNA, a molecule that helps regulate which genes are expressed. One way to think of it is that the DNA in our genes provides the blueprint for cells throughout our body; microRNA determines which parts of the blueprint are used. The hepatitis C virus uses the liver's microRNA to survive. A medication that blocks it could be an effective treatment.

Previous studies in chimpanzees infected with hepatitis C found that drugs that block microRNA were safe and highly effective. Trials in humans have been limited. In this new trial, 27 people with chronic hepatitis C infection received 5 weekly injections of an inhibitor of microRNA. Another 9 people got placebo injections. The study found that:

• The levels of hepatitis C virus in the blood dropped significantly with treatment.
• Higher doses of the medication led to larger reductions in virus levels.
• The reduction in virus levels lasted for more than 3 months after treatment ended.
• No significant side effects were reported and no resistance to the medication developed.

These are impressive findings. Small studies like this are not often published in the New England Journal of Medicine. However, this study was worth making an exception: It describes a significant benefit for a common and potentially serious disease using a novel treatment.

Even before this study was published, I've noticed a lot of optimism among my colleagues who treat hepatitis C. Reports of promising treatments have raised hopes for the millions of people infected with this virus.

What Changes Can I Make Now?

Take steps to avoid becoming infected with hepatitis C, such as:

• Not using intravenous drugs or snorting cocaine
• Limiting the number of sexual partners you have and using barrier contraceptives (such as condoms)
• Following "universal precautions" (the standard infection control guidelines) if you are a healthcare worker
• Choosing a reputable establishment that uses proper cleaning procedures if you decide to have a tattoo or a body piercing

If your sexual partner is infected with hepatitis C or if you have other risk factors (such as intravenous drug use), talk to your doctor about being screened. The Centers for Disease Control and Prevention recently announced recommendations to screen adults born between 1945 and 1965, the baby boom generation. About 75% of cases of hepatitis C are found in this population.

If you already have hepatitis C, review all of your treatment options with your doctor. Steps you can take to reduce your risk of further liver damage or complications include:

• Limiting or avoiding alcohol
• Avoiding medications (such as high doses of acetaminophen) that may cause additional liver damage
• Taking medications to fight the virus (such as interferon and ribavirin)
• Getting your blood tested and ultrasound tests of the liver to screen for liver cancer

Stay up to date on advances in treating hepatitis C. The recommendations for your infection could change in the near future.

What Can I Expect Looking to the Future?

New medications for the treatment of hepatitis C are likely to be approved in the near future. This may include treatments that target microRNA, although larger and more complex studies will be needed first.

Of course, even the best treatments can't compete with prevention. Improving measures to prevent hepatitis C infection should be a priority for researchers, doctors and public health officials as well.

As we learn more about how to prevent and treat this virus, I am hopeful that hepatitis C will someday be a disease primarily of historical interest.