MS-N158 · Proprietary shiitake-mycelial extract · HPV · Phase II prevention research · Appraised 27 October 2026

Can the proprietary AHCC extract clear persistent high-risk HPV infection?

Evidence at a glance

• Evidence label: Small randomized signal; cancer prevention not established
• Benefit: A 50-person phase II study reported HPV clearance among some women receiving AHCC 3 g/day.
• Certainty: Low. The trial was small, reporting combined blinded and later unblinded exposure complicates interpretation, and independent replication is needed.
• Risk: The exact proprietary extract matters; commercial products, doses and quality may differ. HPV surveillance and treatment must continue.

What was studied

Fifty women older than 30 with high-risk HPV persisting for more than two years were randomized double-blind to placebo for 12 months or AHCC 3 g orally once daily for six months followed by placebo. Twelve placebo participants later elected unblinded AHCC.

What the evidence found

Across 34 women who received AHCC in blinded or unblinded phases, 58.8% cleared persistent HPV by the report’s RNA/DNA criteria. Combining randomized and crossover exposure does not provide a simple randomized absolute effect. The study did not measure cervical-cancer incidence or mortality.

How to interpret it

HPV clearance is clinically relevant, but it is not proof that AHCC prevents cervical cancer or treats an established cancer. Vaccination, guideline-based screening, colposcopy and treatment of high-grade lesions remain central.

Practical safety context

The small trial reported no significant adverse effects, but rare harms and interactions cannot be excluded. Confirm the exact formulation; discuss use during pregnancy, liver disease, autoimmune conditions or systemic cancer therapy.

Questions for the care team

• What HPV type, duration and cytology/biopsy result is present?
• What surveillance or treatment is recommended regardless of supplement use?
• Does the product exactly match the researched AHCC preparation?

Funding and conflicts

The lead investigator reported receiving unrestricted research grants from AHCC’s manufacturer before 2014. This product-specific relationship and the small sample lower confidence until independently replicated.

Sources

• Phase II AHCC trial (PMID 35814366)
• Full text (PMCID PMC9256908)
• ClinicalTrials.gov NCT02405533
• NCI: cervical cancer causes and prevention

Last literature search: 27 October 2026. Record appraisal: 27 October 2026. This page is educational and does not replace individualized medical advice. Symptom, biomarker, immune-marker or nutritional changes must not be interpreted as proof of tumor control, recurrence prevention or longer survival unless those outcomes were directly tested.