Melatonin could be a possible treatment option for COVID-19, a new study from the Cleveland Clinic said.

As COVID-19 continues to spread in the United States, the U.S. Food and Drug Administration found that repurposing drugs was the most efficient and cost-effective approach, said a news release.

In the findings published Monday in PLOS Biology by Lerner Research Institute, researchers found melatonin as one of those candidate drugs.

They said melatonin was "associated with a nearly 30% reduced likelihood" of getting a positive test result for SARS-CoV-2, when adjusted "for age, race, smoking history and various disease comorbidities." SARS-CoV-2 is the virus that causes COVID-19.

Notably, when the data was adjusted for African Americans and the same variables, the likelihood of testing positive for the virus increased from 30 to 52 percent. 

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What is Melatonin?

Melatonin is known as an over-the-counter option that can aid in a good night's sleep. It controls the body's sleep-wake cycle.

Looking at large-scale electronic health records of Cleveland Clinic patients, the researchers "harnessed network medicine methodologies... to identify clinical manifestations and pathologies common between COVID-19 and other diseases," said FOX News.

Specifically, they measured the differences between host genes and proteins associated with other illnesses like malignant cancer and autoimmune, pulmonary disorders, and the like.

They drew their conclusion based on "closer proximity," which indicates a higher likelihood that the diseases may have pathological links.

The two main causes found in most severe COVID-19 cases were respiratory distress syndrome and sepsis, the researchers said.

The researchers noted that proteins associated with these two conditions showed a high level of connections with multiple proteins in the coronavirus. 

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Feixiong Cheng, Ph.D., lead author of the study, said these results signal that the drugs may have some utility to treat COVID-19 since it was already approved to treat the other respiratory conditions.

The researchers also found that autoimmune, pulmonary, and neurological diseases had the closest genes and proteins to the coronavirus.

Besides melatonin, they also found 33 other drugs as possible repurposing candidates, but melatonin was "chief among them." 

Researchers Urge Caution with Melatonin

Still, Cheng urged people to exercise caution.

"It is very important to note these findings do not suggest people should start to take melatonin without consulting their physician," Cheng said.

He reiterated that the data still needs to undergo further research. It has to be verified under a large-scale study with randomized controlled trials, said Cheng.

These trials will be critical in validating the clinical benefits of melatonin for patients with COVID-19. Still, researchers are looking forward to the contributions of their research in treating COVID-19 patients.

Cheng said that knowledge of how the coronavirus interplays with other diseases are the key in understanding the disease's complications, especially since COVID-19 has shown evidence of impacting multiple cell types. 

"Our study provides a powerful, integrative network medicine strategy to predict disease manifestations associated with COVID-19 and facilitate the search for an effective treatment," Cheng noted.

Last month, researchers from Columbia University in New York also conducted a study showing patients who need to be intubated may benefit from the treatment, reported News Medical.

The earlier research was published pre-print in the server medRxiv as it underwent peer review.