Suzhou Kintor Pharma (HK: 9939) reported proxalutamide was 100% effective in a US Phase III trial in preventing hospitalization and death among COVID-19 patients. The drug was 100% effective after seven days of treatment, but showed efficacy after only one dose. The trial, which enrolled all patients, no matter their vaccination history, was especially effective in middle-aged and elderly patients with high-risk factors. Proxalutamide is an ACE2 (angiotensin-converting enzyme 2) and TMPRSS2 (transmembrane protease, serine 2) inhibitor that prevents the entry of the SARS-CoV-2 virus into host cells. Kintor says it will file for Emergency Use Approvals in the US, China and elsewhere.

The Phase III trial enrolled 733 patients with mild to moderate COVID-19. Patients were randomized 1:1 to once-daily proxalutamide or placebo plus standard of care. Among patients with more than 7 days of treatment (N=693), 6 placebo patients were hospitalized (including one death) compared to no hospitalization/death in the proxalutamide group.

The study demonstrated that proxalutamide was well tolerated and side effects were manageable in patients with mild to moderate COVID-19.

Kintor also reported that proxalutamide reduced SARS-CoV-2 viral load from Day 3 to Day 28, compared to the control group and reduced COVID-19 symptoms, including fever, shortness of breath and cough. Proxalutamide is a nonsteroidal antiandrogen that is also in development to treat prostate and breast cancer.

Dr. Tong Youzhi, the founder, Chairman, and CEO of Kintor Pharma, said, "The top-line data of this pivotal study demonstrates the clinical efficacy of proxalutamide in the mostly US COVID-19 population with a significant reduction of hospitalization and death rate in patients. It is important to note that proxalutamide has showed COVID-19 viral load reduction against both Delta and Omicron variants, which is important as new variants continue to arise."

For COVID-19 patients with early symptoms, proxalutamide targets the ACE2/TMPRSS2 signal axis to inhibit the entry of the virus into host cells. For severe patients, proxalutamide promotes the clearance of pathogens and decreases inflammation by activating the Nrf2 pathway, which inhibits the over-production of IL-6, proinflammatory cytokines, and chemokines. This minimizes cytokine storms and tissues damage. Kintor believes the candidate could show efficacy for all COVID-19 patients from early symptoms to hospitalized/severe conditions.

Kintor is developing a portfolio of innovative small molecule and biological therapeutics for androgen-receptor-related disease areas with unmet medical needs, including COVID-19, prostate, breast and liver cancers, alopecia and acne.

See our other articles on Kintor.

Disclosure: none.