Alexion Pharmaceuticals (NASDAQ:ALXN) recently announced that it would initiate a phase 3 study to investigate the safety and efficacy of Ultomiris as a treatment for COVID-19. Ultomiris is already approved for the treatment of paroxysmal nocturnal hemoglobinuria, a rare blood disease that causes red blood cells to break apart and release hemoglobin, the component in red blood cells that carries oxygen around the body. This drug has been used on a compassionate basis to treat COVID-19 patients, and the results have, so far, been encouraging, which is why Alexion is launching a formal clinical trial.

This study, which is set to start in May, will enroll about 270 patients in several countries that have been severely impacted by the ongoing outbreak. It will focus on patients with severe manifestations of COVID-19, namely "those who are hospitalized with severe pneumonia or acute respiratory distress syndrome."

Face mask with COVID-19 written on it.

Image Source: Getty Images.

Several other pharma companies are currently pursuing potential treatments for COVID-19, among them Gilead Sciences (NASDAQ:GILD). Back in February, it initiated two phase 3 clinical trials to study the efficacy of its antiviral drug, remdesivir, as a potential treatment for COVID-19. The company enrolled about 1,000 patients in multiple countries, including 400 patients with severe manifestations of COVID-19, and 600 patients with mild manifestations of the disease. Patients received either five or 10 doses of remdesivir.

While we don't have data from these clinical trials yet, early anecdotal results from the arm of a remdesivir study being conducted at  University of Chicago Medicine were encouraging. According to STAT, an online trade publication that focuses on the healthcare sector, among 125 patients who were treated with remdesivir, most had been released from the hospital, and only two died. 

However, even the doctor heading the overseeing the remdesivir study at University of Chicago Hospital warned that it was too early to draw definitive conclusions, and because the study does not include a control/placebo arm, interpreting the results will be more difficult.