Japanese trading and pharmaceutical company Kowa Co Ltd said on Monday anti-parasite drug Ivermectin showed an "antiviral effect" against Omicron and other variants of coronavirus in joint non-clinical research.
The company, which has been working with Tokyo's Kitasato University on testing the drug as a potential treatment for COVID-19, did not provide further details.
Clinical trials are ongoing, but promotion of Ivermectin as a COVID-19 treatment has generated controversy.
Prominent vaccine skeptic Joe Rogan, whose podcast on Spotify has prompted protest by singers Joni Mitchell and Neil Young, has long stirred controversy with his views on the pandemic, government mandates and COVID-19 vaccines.
Rogan has questioned the need for these vaccines on his show and said he used Ivermectin.
The drug is not approved for treatment of COVID-19 in Japan, and the US Food & Drug Administration, the World Health Organization, the EU drug regulator and Merck, which makes the drug, have warned against its use due to a lack of scientific evidence that it has therapeutic effect.
In guidance on its website dated September 2021, the FDA noted growing interest in the drug for preventing or treating COVID-19 in humans, but said it had received multiple reports of patients who had required medical attention, including hospitalization, after self-medicating with it.
Many potential COVID treatments that showed promise in test tubes, including the antimalarial hydroxychloroquine promoted by former US President Donald Trump, ultimately failed to show benefit for COVID-19 patients once studied in clinical trials.