Why A Core Ingredient Of Viagra May Help Treat Covid-19

Once again, innovative thinking about how existing pharmaceuticals that treat underlying conditions similar to those affected by Covid-19 may help mitigate the coronavirus' impact on patient health.

Such imaginative analysis and collaboration is one of the most significant by-products of the crisis so far and will have important implications for health care in the future. JL


Virginia Streva reports in Philly Voice, image by Ricardo Figueroa:

Naturally produced by the body, nitric oxide relaxes blood vessels, increasing the amount of oxygen being transferred to the blood and reducing the heart's workload. The molecule is already used to treat heart disease, erectile dysfunction and respiratory illness. The gas led to Viagra after scientists discovered (it) helps increase blood flow to the penis. Hospitals in Boston, Alabama, Louisiana, Sweden and Austria are testing patients with moderate symptoms of COVID-19. Patients inhale nitric oxide through a CPAP machine.

Nitric oxide, a gas that could improve breathing and potentially mitigate severe symptoms of the coronavirus, is among the latest contenders in the race to find a treatment for COVID-19. 

Naturally produced by the body, nitric oxide relaxes blood vessels, increasing the amount of oxygen being transferred to the blood and reducing the heart's workload. The molecule — not to be confused with nitrous oxide or laughing gas — is already used to treat heart disease, erectile dysfunction and respiratory illness.

Hospitals in Boston, Alabama, Louisiana, Sweden and Austria have started a clinical trial to test the treatment on patients with mild to moderate symptoms of COVID-19. Patients inhale nitric oxide through a CPAP breathing machine for 20 to 30 minutes. The treatment is given twice a day for two weeks. 

“We have tremendous confidence this therapy will alter the devastating effects of COVID-19 but we must test it," Dr. Keith Scott, principal investigator at Louisiana State University Health in Shreveport, Louisiana told the Boston Herald. "If results show promise, and since this gas is already FDA approved, widespread use could begin immediately.” 

The treatment has shown promise in COVID-19 patients in Italy, appearing to significantly boost oxygen levels in their blood, Dr. Lorenzo Berra, a critical care specialist at Massachusetts General Hospital, told the Los Angeles Times. 

A second trial at Massachusetts General Hospital, which is currently under review, would attempt to test the gas' ability to mitigate the onset of COVID-19 to health care workers who are at a greater risk of contracting the virus due to constant exposure, according to the Los Angeles Times. In this study, workers would inhale the gas for 10 to 15 minutes at the start and end of their shift every day. 

Nitric oxide has been used for decades to treat a variety of conditions. 

The colorless gas was named "molecule of the year" in 1992 after it became a successful treatment for newborns suffering from heart defects and pulmonary hypertension. 

The gas also led to Viagra, an erectile dysfunction drug, after scientists discovered the molecule helps increase blood flow to the penis. The drug increases nitric oxide in the body by inhibiting a particular enzyme, PDE 5. Due its usefulness in increasing blood flow, Chinese doctors are currently testing Viagra as a potential treatment for coronavirus patients with moderately troubled breathing. 

Nitric oxide previously has been used to treat other coronaviruses, including SARS. The virus' ability to replicate was significantly diminished when the gas was administered, according to a 2004 Swedish study.

Several other drugs also are being tested as COVID-19 treatments.

Penn Medicine is leading a clinical trial to test the effects of hydroxychloroquine, an anti-malarial drug that's also known to treat lupus and rheumatoid arthritis, on coronavirus patients. The drug has been popularized in the media, but initial research has produced mixed results. 

Several clinical trails are currently investigating remdesivir, anti-viral drug for Ebola that has showed promising results for SARS and MERS. The National Institute of Allergy and Infectious Disease have begun a double-blind Phase 2 trial into the medicine.