Researchers are reporting that a new experimental drug holds promise in treating genital herpes, a sexually transmitted infection that is currently considered incurable.

Researchers studied the drug pritelivir and found that it substantially slowed viral shedding in individuals with genital herpes (HSV-2), meaning it cut the overall infection window in half.

The findings are based on a study of 156 patients who researchers followed for four weeks. While the results are hopeful, experts stated that the results are still considered preliminary.

However, the researchers stated that the results are definitely important, due to the fact that pritelivir is the first in a new class of medications that are designed to work differently than current herpes treatments. The study has given hope that pritelivir will work better when it comes to preventing viral transmission.

Genital herpes is caused by the herpes simplex virus and is known as HSV-2. It is estimated that 16 percent of Americans between the ages of 14 and 49 have an HSV-2 infection.

HSV-2  causes painful sores around the genitals, mouth, and rectum. It is important to note however, that in many cases it causes only mild symptoms, which can lead many individuals to believe they are not infected.

If HSV-2 is passed from a mother to her unborn child, the child is at risk for serious complications that include a deadly brain infection.

Currently, there is no cure for genital herpes. After an individual becomes infected, HSV tends to lie dormant in nerve cells and reactivate only periodically. In many cases, re-activation only causes mild symptoms. There are three medications that are commonly prescribed to treat symptoms, and suppress outbreaks. They are acyclovir-brand name Zovirax, famciclovir- Famvir and valacyclovir-Valtrex.

Even with that daily treatment with prescription medications, there is still the chance of the virus shedding. Current drugs only minimize viral shedding by 50 percent.

The research study was funded by German drug maker AiCuris It featured 156 adults who were infected with HSV-2 . Each subject was randomly assigned to one group, and there were five groups total.  The first group was given a placebo and the other four were given different doses of pritelivir.

The study took place over 28 days, and the patients that showed the highest amount of effects were the patients who were given the highest dose of 75 milligrams per day.  A second group that received 400 milligrams per week also showed significant results in viral shedding. The once-a-week results were significant, as a once-a-week treatment would provide added convenience for herpes sufferers.

There were no major side effects from the medication, which is also significant, but it is important to note that the study was short term; so long term effects could not be recorded.

Further clinical trials of the drug are currently paused because the U.S. Food and Drug Administration ordered the research project to stop when research monkeys displayed physical abnormalities. So far, there have been no known adverse effects in humans.