A Japanese mushroom extract, active hexose correlated compound (AHCC), appears to be effective in eradicating persistent human papillomavirus (HPV) infection, according to results of a small pilot study.

Ten women with persistent HPV infection received a once-daily oral dose (3 g) of AHCC for up to 6 months, and half of the participants achieved a negative result for HPV infection.

Three of these women with a confirmed eradication have stopped using AHCC, and the remaining two responders are continuing on the study.

The results were presented at the 11th International Conference of the Society for Integrative Oncology.

Lead investigator Judith A. Smith, PharmD, pointed out that the five women who didn’t respond did not receive a full 6 months of treatment.

“We were initially optimistic that we were going to clear the infection in a month, and at first we were testing the women weekly,” said Dr Smith, associate professor in the Department of Obstetrics, Gynecology and Reproductive Sciences at the University of Texas Health Sciences Center at Houston Medical School. “When our first patient didn’t respond at 5 weeks, we assumed that it wasn’t effective and we took her off treatment.”

The researchers then realized that more time was needed, so after waiting 8 weeks, another nonresponder was removed from therapy. Two more participants were also taken off treatment at 3 months, after they did not clear the virus. “Now we know that we need to give it at least 6 months to realize the full effect,” she told Medscape Medical News. “These patients will be eligible to go back on treatment.”

While most HPV infections are self-limiting and resolve without causing any symptoms, there is currently no effective treatment for those that persist and that the body’s innate immune system cannot clear.

“That is why this is so encouraging,” said Dr Smith. “We test women for HPV, and if they have a persistent infection, there is nothing we can do for them except watch and wait.”

Phase 2 in the Works

AHCC is an extract prepared from co-cultured mycelia of several species of Basidiomycete mushrooms. Preclinical studies have shown it to have anticancer properties, and both in vitro and in vivo studies have confirmed that it can eradicate HPV. Its ability to eradicate oncogenic HPV types 16/18 is attributed to modulation of the expression and signaling of interferon-α, β, and γ.

“We’ve been evaluating the efficacy of AHCC with chemotherapy for over a decade,” said Dr Smith. “It is a nutritional supplement with no known side effects, and it modulated the immune system to fight off infections and inhibit tumor growth.”

It is commercially available over the counter, and no adverse effects were associated with its use, Dr Smith noted. “This study confirms our preclinical findings, that it can eradicate HPV.”

Dr Smith emphasized that these are preliminary data, and the pilot study’s purpose was to define the appropriate dose and duration of therapy. A phase 2 randomized, double-blind trial is getting underway, and they will begin enrollment in about 2 weeks. “We would also like to investigate at some point if AHCC can actually prevent infection, or prevent re-infection,” she explained. “We’d like to see if it can help build up the immune system to the point of resisting infection with HPV.”

Treating Warts?

Anecdotally, she has had inquiries from both men and women about using AHCC to treat genital warts caused by HPV. “Since it’s a commercially available product sold without a prescription, and AHCC has had no reported side effects when taken appropriately, I told them they could try it,” she said, “Even though we have no information on that.”

Several people have reported that their lesions cleared up after using AHCC and have not returned. “One woman told me that a plantar wart disappeared, which was very interesting,” Dr Smith continued. “We don’t have any details on these cases with warts, but I have told them to keep me in the loop, because this may be something we can study later on in future trials.”

Because about 75% of adults in the United States have been exposed to HPV, the researchers were very careful to make sure that the study participants had a persistent infection, one that was not likely to clear on its own.

To minimize potential confounders, all of the participants were older than age 30 years and had a positive HPV test result within 3 months of entry into the study. To establish persistent infection, they had to have another positive test result no less than 6 months and no more than 18 months before enrollment.

“While a provocative study outcome, it must be emphasized that this is a very small sample size, and it is quite unclear if these infections would have resolved without any treatment,” said Maurie Markman, MD, from the Cancer Treatment Centers of America in Philadelphia. “Alternatively, there may have been issues with the HPV testing itself.”

“The plans for a well-designed randomized study are appropriate,” said Dr. Markman, who was not involved in the study. “The results of this larger trial will be awaited with keen interest.”