Prof Finds Herpes Vaccine

A new herpes vaccine developed by a Harvard Medical School (HMS) professor may soon be approved for human testing, according to a new study by the National Institute of Allergy and Infectious Diseases.

HMS Higgins Professor of Microbiology and Molecular Genetics David Knipe, who has been developing a vaccine for 15 years, said he discovered it unexpectedly after testing mice with mutant viruses.

“The vaccine is a genetically engineered virus missing essential replication genes,” Knipe said.

He explained that the vaccine prevents herpes because it causes the virus to only partially complete its replication process.

“It makes a large number of herpes proteins but it doesn’t make the virus,” he said.

This then enables cells to produce antibodies and T-cells that help to regulate the immune system and prevent infection.

According to the National Institute of Allergy and Infectious Diseases website, there are two types of the herpes virus, HSV-1 and HSV-2, both of which can cause genital herpes.

Currently, there is no cure for HSV-2, the sexually transmitted variant, which affects about one out of every five Americans over the age of 12. Knipe’s vaccine targets HSV-2, which is also responsible for oral herpes, or cold sores.

The American Society for Microbiology’s website notes that the virus can be especially harmful to patients with weakened immune systems, like those with AIDS.

The search for a herpes vaccine closely parallels that for the cure for HIV, the virus that causes AIDS, since the prevention of both viruses involves the generation of antibodies and T-cells. While acknowledging that his research provides new hope for the possibility of an HIV vaccine, Knipe said that there is no direct correlation between the two.

“The hurdles are similar,” he said, “but this doesn’t immediately tell us how to make an AIDS vaccine.”

Knipe said that it will still take several years for the vaccine to be cleared for public use. He noted that failed herpes vaccines have made drug companies wary of investing in human testing, but that new, positive data for his vaccine will make it a more viable candidate.

“We hope that within a few years trials can be started for a therapeutic vaccine,” Knipe said.

The vaccine will undergo two types of clinical trials, Knipe said. The first will be a therapeutic trial with people who have already contracted herpes, to see if the vaccine can reduce the infection, while the second will test its preventative capacity in people without the disease.

Knipe noted that therapeutic trials are generally easier to run because they require fewer people and take less time. He said that there has already been a huge demand for the vaccine, and that he has received e-mails from patients willing to volunteer for trials and doctors eager to run them.