Researchers from the University of Minnesota Medical School have found that the commonly prescribed blood pressure medication, losartan (Cozaar), is ineffective in reducing hospitalization for patients with mildly COVID-19 infection.

The researchers conducted a trial in which non-hospitalized patients recently diagnosed with COVID-19 were given either losartan or a placebo. The patients were monitored for 15 days.

The findings, published in an open-access journal called EClinicalMedicine, showed that losartan does not reduce the likelihood of hospitalization in mild cases. Also, the drug does not appear to aggravate the symptoms of COVID-19 or have any significant side effects.

The study’s co-principal investigator Dr. Michael Puskarich said, “Based on our results, there is no benefit to starting losartan for newly diagnosed outpatients with COVID-19, but those who are already taking the medication for pre-existing health conditions should feel safe continuing it.”

Dr. Puskarich is an associate professor in the Department of Emergency Medicine at the U of M Medical School.

There have been conflicting hypotheses since the pandemic began, which led the team to investigate losartan as a potential COVID-19 treatment option. Some experts believed losartan may reduce inflammation and help in quick recovery, but others expressed concerns over worsening of COVID-19 symptoms with the drug.

Another co-principal investigator Dr. Christopher Tignanelli said, “Given SARS-CoV-2 binding with ACE2 there has been significant research interest into the utility of ACE and AT1R blocking agents to combat COVID-19. This study provides insight that for patients with mild COVID-19, who do not require hospital admission, that there is no benefit or harm from such agents.”

Dr. Tignanelli is an assistant professor in the Department of Surgery at the U of M Medical School.

The same research team has also been working on another trial for inpatients to evaluate whether losartan can prevent lung injury in hospitalized patients with pneumonia caused by COVID-19.

Losartan is a prescription medication used to treat high blood pressure (hypertension). By controlling high blood pressure, the drug reduces the risk of heart attack, stroke, and kidney disease.

Losartan belongs to a family of drugs called angiotensin receptor blockers (ARBs). Other widely prescribed ARBs include olmesartan (Benicar), valsartan (Diovan), and telmisartan (Micardis). ARBs work by dilating the blood vessels so blood can flow easily throughout the body. The article was published in Science Daily.