Proxalutamide reduces COVID-19 mortality risk by 92 percent

In a clinical trial, Proxalutamide reduced COVID-19 mortality risk by 92 percent and shortened the median hospital stay of patients by nine days.

The investigator-initiated trial (NCT04728802), conducted by Dr Andy Goren and Dr Flávio Adsuara Cadegiani at 12 sites in the Brazil, is a placebo-controlled, double-blinded randomised parallel assignment study. The trial has two cohorts (men and women) and two arms (Proxalutamide and control). It enrolled 588 patients, aged 18 years and older with a clinical status of 3, 4 or 5 on the WHO COVID-19 Ordinal Scale (3 = hospitalised patients not needing oxygen therapies, 4 = hospitalised patients needing oxygen by mask or nasal prongs and 5 = severely ill hospitalised patient on non-invasive ventilation or high-flow oxygen).

In the Proxalutamide arm, patients were orally administered 300mg of the drug once daily for 14 days. In the control arm, patients were orally administered placebo once daily for 14 days. Each arm also received standard of care as determined by the principal investigator at the site.

The trial met its primary endpoint, with Proxalutamide significantly reducing patient statuses on the Ordinal Scale at day 14. Proxalutamide achieved a reduction of 4.01 from baseline (5.663 to 1.653), compared to control with a reduction of 0.25 from baseline (5.618 to 5.368).

Proxalutamide was also found to reduce the mortality risk by 92 percent; overall, 11 patients died by day 14 in the treatment arm, making the mortality rate 3.7 percent, comparatively there were 141 deaths in the control arm, a 47.6 percent mortality rate.

Additionally, treatment with the nonsteroidal antiandrogen shortened median length of hospital stay by nine days (five days with Proxalutamide versus 14 with control) and after 14 days, 89.1 percent of those treated with Proxalutamide were discharged, more than double the 32.8 percent in the control arm.

Dr Tong Youzhi, Founder, Chairman and Chief Executive Officer of Kintor Pharmaceutical Limited (the developer of the drug), commented: “This trial for treatment of hospitalised COVID-19 patients was conducted in 12 sites in the Brazilian state of Amazonas, where the pandemic has been devastating. Most of the newly test-positive patients in Amazonas have been infected by the new P.1 variant, which is more contagious and has led to a higher mortality rate. We are delighted to see that Proxalutamide could significantly reduce the mortality rate, shorten the length of hospital stay, reduce the number of new mechanical ventilations (MV) and increase the percentage of discharge from hospital, thus alleviating shortages of public health resources in Amazonas.

“Based on the positive results of this Phase III trial, the treatment of COVID-19 outpatients, hospitalised patients (including those admitted to Intensive Care Units), we expect Proxalutamide could become an important tool in the global fight against COVID-19.”

Proxalutamide (GT-0918) is a nonsteroidal antiandrogen which was developed for the treatment of prostate and breast cancer.