New Phase II Clinical Trial Suggests that Mushroom-Derived AHCC Is Effective at Clearing Persistent HPV Infections

People who have high-risk HPV fear getting cancer, but don’t know how to prevent it. The only advice doctors can provide is to support the immune system by eating well, sleeping well, and reducing stress. In support groups, survivors of HPV cancers express great fear that their HPV will lead to cancer yet again. So, for people who have high-risk HPV, any research on a supplement that supports the immune system’s ability to clear persistent HPV infections is profoundly significant. This new phase II study showing that AHCC is 58% effective at clearing persistent HPV infections provides hope for those of us who have high-risk HPV.

A persistent HPV infection is defined as one that lasts for more than two years, and the longer an HPV infection is active, the more likely it is that abnormal cancer cells will form. Although most people clear HPV infections naturally in 2 years if their immune system is strong, not everyone has a strong immune system. The immune system can be compromised by poor diet, insufficient sleep, stress, or just age. About 10% of people with HPV infections have persistent infections that last for more than 2 years. Since persistent high-risk HPV infections are the most likely to cause cancer, it is important to study these cases.

To date, there is no systemic treatment for persistent HPV infections. Current treatment modalities rely on early detection in vaginal PAP smears followed by treatments like cryotherapy, surgical excision, loop electrosurgical excisional procedure (LEEP), or cold knife conization. Although these treatments have a high response rate of 80%, patients will frequently have recurrent lesions. In addition, there is not yet an established medical protocol for screening and treating HPV infections in other parts of the body, like the anus. The Anchor Study, for example, has shown that screening for HPV and treating precancerous cells can lower the incidence of anal cancer. But this type of screening is in its infancy and only available in select locations. It would therefore be better to prevent these cell changes from happening in the first place. This phase II study of AHCC supplementation provides hope that persistent HPV infections can be prevented from progressing to cancer.

What Is AHCC?

The AHCC supplement is a proprietary, standardized extract of cultured lentinula edodes mycelia that has been shown to have unique immune modulatory benefits. Several animal and human studies have reported a variety of therapeutic effects, including enhanced antioxidant effects, anticancer activity, and modulation of the immune system to prevent the infectious processes of both viral and bacterial infections.  This new clinical trial suggests that AHCC can also help the immune system clear persistent HPV infections.

Pilot Studies of AHCC to Clear HPV Infections

AHCC originally showed promise in two pilot studies. In one study of women with persistent HPV infections, 4 out of the 8 women who remained in the study (50%) cleared their persistent HPV infection between 3 to 6 months after starting a 3g daily dose of AHCC on an empty stomach.  In a second pilot study, women were given 1g of AHCC a day on an empty stomach and showed a similar response rate: 4 out of the 9 women (44%) confirmed clearance of high-risk HPV persistent infections after 7 months of supplementation. These pilot studies provided the rationale to move forward with a phase II trial of AHCC to clear persistent HPV infections.

The New Phase II Study

Our medical advisory board member Judith Smith conducted this phase II randomized, double-blind, placebo-controlled study with a post unblinded study. This trial was reviewed and approved by the University of Texas Health Sciences Center Institutional Review Board. The objective of the study was to determine the efficacy, safety, and durability of AHCC supplementation for 6 months to support the host immune system to clear high-risk HPV infections.

Fifty women over age 30 with persistent HPV infections that had lasted more than two years were studied for 12 months. Patients were randomized into two groups: one group took AHCC 3g by mouth once daily on an empty stomach for six months followed by a placebo for the remaining 6 months. The control group was given a placebo. Every 3 months patients were evaluated with HPV-DNA and HPV-RNA testing and with a blood sample to evaluate a panel of immune markers including: interferon‐alpha(INN), interferon‐beta (IFNβ), interferon‐gamma (IFN), IgG1, T‐lymphocytes, and natural killer(NK) cell levels.

Of the 41 women who completed the study, fourteen (63.6%) of the 22 patients in the AHCC supplementation arm were HPV-RNA/HPV-DNA negative after six months, and 64.3% (9/14) achieved a durable response defined as also being HPV-RNA/HPV-DNA negative 12 months after the supplementation ended. In contrast, in the placebo arm of the study, only two (10.5%) of 19 patients were HPV negative at 12 months. An additional twelve patients completed the un-blinded study and 50% were HPV-RNA/HPV-DNA negative after six months of AHCC supplementation.

Combining all 34 participants that received AHCC supplementation gives an overall response rate of 58.8% that cleared HPV persistent infections.


Results from this phase II study demonstrated that AHCC 3g once daily on an empty stomach was effective in supporting the host immune system’s elimination of persistent HPV infections and was well tolerated with no significant adverse side effects reported.

Directions for Further Research

 An additional finding of the study was that suppression of IFNβ to less than 20pg/mL correlated with an increase in T‐lymphocytes and IFN and durable clearance of HPV infections in women that received AHCC supplementation. This merits further evaluation as a clinical tool for monitoring patients with HPV infections. The duration of AHCC supplementation required beyond first negative result also needs more evaluation to optimize success for durable outcomes.

AHCC is Unique

It’s important to distinguish AHCC from other medicinal mushrooms. AHCC is the only medicinal mushroom that has been clinically demonstrated to help eradicate HPV. It is not interchangeable with other medicinal mushrooms because it has been specially developed and processed to maximize its immune-boosting capacity. AHCC is made by cell culturing a specific subspecies of mushroom identified by Japanese scientists several decades ago to have the greatest ability to increase natural killer cell activity. Its molecular weight has been reduced using a patented enzymatic process to improve its absorption and clinical efficacy. Every batch of AHCC is subjected to DNA pattern testing to confirm its identity (in other words, to ensure it is genuine AHCC). These innovations make AHCC unique among medicinal mushrooms.

AHCC is available from multiple nutritional supplement companies, but it is important to steer clear of fake products using different names yet claiming similar benefits. Only genuine AHCC® has been clinically tested and found to help clear HPV.

Click to read the full study

Here is a list of genuine AHCC products.

AHCC® is a registered trademark of the Amino Up Company

A Note for Anal Cancer Survivors

Because this study was conducted on women with vaginal HPV infections, we reached out to Dr. Romesser, a radiation oncologist specializing in anal cancer at Memorial Sloan Kettering, to ask about anal cancer survivors and AHCC. No side effects from AHCC were reported in women with vaginal HPV in the study described above; however, there is some anecdotal indication that there may be mild side effects for anal cancer survivors. Dr. Romesser has noticed that some anal cancer survivors experience side effects like anal itching when they start taking AHCC. Therefore, he recommends that anal cancer patients who have recently had treatment, wait to take AHCC until all the side effects from treatment have subsided.  It also seems that for some anal cancer survivors, the side effects from taking AHCC go away after a few weeks. It might be worthwhile to continue taking AHCC for a few weeks despite any side effects in case the side effects subside.


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