Use of fungal mycelia, which has antiviral properties, constitutes a novel strategy for addressing existing and newly emerging viral diseases. We evaluated safety and feasibility of fungal mycelia (Fomitopsis officinalis and Trametes versicolor, FoTv) for treatment of COVID-19 and assessed its antiviral effects and potential to reduce symptoms. In a randomized, double-blind, placebo-controlled, dual site (UCSD/UCLA medical centers) clinical trial we examined non-hospitalized patients who contracted mild-to-moderate COVID-19 ≤ 96 hours, and experienced symptom onset ≤ nine days, before enrollment. FoTv was safe, well-tolerated, and feasible for COVID-19 treatment. Minor differences in biochemical markers were observed between groups (26 FoTv, 24 Placebo). FoTv significantly reduced the number and severity of symptoms, particularly sore throat/cough, and in vitro SARS-CoV-2 (pseudovirus) cellular infection. In conclusion, FoTv was safe and reduced COVID-19 symptoms and cellular viral infection. Future studies should investigate therapeutic benefits of fungal mycelia for SARS-CoV-2 and other viruses. Clinicaltrials.gov registration: NCT04667247.
Saxe, G., Shubov, A., Smith, C. N., Golshan, S., Shekhtman, T., Wilson, S., Slater, D., Bair, Z. J., Beathard, C., Davis, R. A., MacElhern, L., Kao, L. K., Senowitz, P., Gosnell, N., Buchholz, D., & Aguilar-Carreno, H. (2026). Polypore mushroom mycelia for treatment of active COVID-19 infection: A randomized clinical trial (p. 2026.06.01.26354267). medRxiv. https://doi.org/10.64898/2026.06.01.26354267