Researchers are testing a vaccine that shows great promise in preventing hepatitis C, a disease with which an estimated 118 million people around the world are infected.
A cure for viral hepatitis C, an illness previously resistant to treatment, was announced recently with great fanfare, but the course of drugs needed to fight the liver disease costs about $80,000, a price most people cannot afford.
Now, however, a vaccine that protects against hepatitis C is on the horizon. A combination of an inactive chimpanzee cold virus and a hepatitis protein has been found to stimulate production of thousands of key immune system cells to guard against infection with the virus.
Eleanor Barnes, a scientist at Oxford University's medical school in Britain, said the drugs that cure hepatitis C don't prevent reinfection with a different strain.
“In contrast, a vaccine, if it’s effective and it’s a good vaccine, can protect patients with one or two injections for the rest of their life," she said. "So, vaccines really have proved themselves historically to be the very best medicine.”
Barnes made her comments in an interview with Science Translational Medicine. This week's edition of the journal includes an article on her work with an international team to develop a hepatitis C vaccine.
Different versions of hepatitis C are common in different parts of the world. Barnes said there’s evidence that the experimental vaccine may protect against more than one strain of the virus.
Vaccines are usually designed to marshal a targeted antibody response to an infection. Antibodies are the immune system's first-line soldiers to recognize a microbial invader and stimulate a broader attack.
What's different about her team's vaccine, Barnes said, is that it stimulates a robust T-cell response. T-cells are other weapons in the body's immune system. These fighter cells target multiple parts of the virus.
Like HIV, the virus that causes AIDS, the hepatitis C virus mutates quickly, hampering vaccine development. And, Barnes said, hepatitis C patients — like those those infected with HIV — often go to the doctor at a late stage of infection when they start to feel sick.
“Many patients will present for the first time to a health care physician when their disease is very advanced, because their disease is a silent one until you get advanced liver disease associated with fibrosis and liver cancer,” Barnes said.
So far, the vaccine has undergone early clinical trials that showed it is safe for use in people. The research paves the way for more advanced clinical trials in the United States among uninfected intravenous drug users, who are at highest risk of contracting the virus.
The vaccine causes short-term side effects, including fatigue and migraine headaches.
Hepatitis C can also be spread by blood transfusions, by the sharing of razors or toothbrushes with someone who has the disease, or through sexual contact.