Didier Raoult, a renowned French microbiologist, announced hydroxychloroquine (HCQ) as an effective cure for COVID-19 on Feb. 25, 2020. The following month, former U.S. President Donald Trump cited his research and called the drug a "game changer." Since then, Dr. Raoult has been engulfed in a global controversy.

Initially, in March 2020, the Food and Drug Administration (FDA) granted HCQ, a drug widely used against malaria and arthritis, an emergency use authorization (EUA) for treating COVID-19.

However, on May 22, 2020, the Lancet medical journal published a now-retracted study saying that HCQ brought about a much higher risk of death and heart problems in hospitalized COVID-19 patients, citing data from nearly 100,000 patients in over 600 hospitals. The authors noted the mortality rate of the total surveyed population was 11.1 percent, while the death rate was 16 percent and higher for the groups given various HCQ treatments—nearly double that of the control group, which was not given HCQ treatment.

The study preceded a series of decisions by health authorities. In three days, the World Health Organization (WHO) suspended a clinical trial of HCQ for COVID-19. During the same week, France also banned its use on COVID-19 patients, revoking an emergency authorization of HCQ for COVID-19 issued two weeks earlier.

On June 15, 2020, the FDA revoked the EUA of HCQ, citing cardiac adverse events and other side effects. Six months later, the FDA approved EUAs for Pfizer-BioNTech and Moderna COVID-19 vaccines, emergency authorizations contingent on "no adequate, approved, and available alternatives," according to the FDA announcement.

"Chloroquine or hydroxychloroquine was prescribed 1 billion times in the year of 2006. So it means that if 10 percent of the people died with this, that would have made 100 million people die of heart attack, which is stupid," Dr. Raoult told The Epoch Times. HCQ is a newer and improved version of chloroquine.