Drug meant for Ebola may also work against coronaviruses

Drug meant for Ebola may also work against coronaviruses

Understanding how drugs work is an important step in developing new treatments for COVID-19

February 27, 2020

Science Daily/University of Alberta Faculty of Medicine & Dentistry

Researchers who have discovered why the drug remdesivir is effective in treating the coronaviruses that cause Middle East respiratory syndrome (MERS) and severe acute respiratory syndrome (SARS) expect it might also be effective for treating patients infected with the new COVID-19 strain.

A group of University of Alberta researchers who have discovered why the drug remdesivir is effective in treating the coronaviruses that cause Middle East respiratory syndrome (MERS) and severe acute respiratory syndrome (SARS) expect it might also be effective for treating patients infected with the new COVID-19 strain.

"Even if you know a drug works, it can be a red flag if you don't know how it works," said virologist Matthias Götte. "It is reassuring if you know exactly how it works against the target.

"We know the drug works against different coronaviruses, like MERS and SARS, and we know the novel coronavirus is very similar to SARS. So I would say I'm cautiously optimistic that the results our team found with remdesivir and MERS will be similar with COVID-19."

The study, published in the Journal of Biological Chemistry this week, is among the first in Canada to discuss the COVID-19 strain.

Until now, there has not been a published explanation of why remdesivir may work against coronaviruses, said Götte, who added his study is an important step in answering that question.

Developed by Gilead Sciences as a response to the 2014 West African Ebola virus epidemic, remdesivir was first used on a patient with the novel coronavirus earlier this year in the United States.

As reported in the New England Journal of Medicine, the patient was given the drug on the seventh day of illness, and showed marked improvement the following day, with symptoms eventually disappearing altogether. And at a recent press conference in Beijing, the assistant director-general of the World Health Organization, Bruce Alyward, said remdesivir is the only drug available that may have real efficacy against COVID-19.

"What our study showed was that remdesivir essentially mimics one of the natural building blocks for RNA synthesis necessary for genome replication of the virus. Enzymes within the virus are synthesizing the viral RNA genome with these building blocks, but they mix up the bits they need with the drug. Once the drug is incorporated into the growing RNA chain, the virus can no longer replicate,"explained Götte.

He said the next step is to wait for results from ongoing clinical trials with remdesivir, which are expected by the end of April. Even then, that won't be the end of the story, he cautioned.

"It's likely we'll need more than one drug to properly fight emerging diseases like COVID-19, as we have with HIV and hepatitis C virus infections," Götte said.

"Ideally, we will have a couple of drugs because certain strains could be resistant to certain treatments."

Götte's study was supported by grants from the Canadian Institutes of Health Research and the Alberta Ministry of Economic Development, Trade and Tourism through the Major Innovation Fund Program and Antimicrobial Resistance -- One Health Consortium.

https://www.sciencedaily.com/releases/2020/02/200227122123.htm

Novel coronavirus (COVID-19) imaging features overlap with SARS and MERS

COVID-19's imaging features are variable and nonspecific, but the imaging findings reported thus far do show

February 28, 2020

Science Daily/American Roentgen Ray Society

Although COVID-19's imaging features are variable and nonspecific, the findings thus far do show ''significant overlap'' with those of severe acute respiratory syndrome and Middle East respiratory syndrome. The early evidence suggests that initial chest imaging will show abnormality in at least 85% of patients, with 75% of patients having bilateral lung involvement initially that most often manifests as subpleural and peripheral areas of ground-glass opacity and consolidation.

COVID-19 is diagnosed on the presence of pneumonia symptoms (e.g., dry cough, fatigue, myalgia, fever, dyspnea), as well as recent travel to China or known exposure, and chest imaging plays a vital role in both assessment of disease extent and follow-up.

As per her review of the present clinical literature concerning COVID-19, Melina Hosseiny of the University of California at Los Angeles concluded: "Early evidence suggests that initial chest imaging will show abnormality in at least 85% of patients, with 75% of patients having bilateral lung involvement initially that most often manifests as subpleural and peripheral areas of ground-glass opacity and consolidation."

Furthermore, "older age and progressive consolidation" may imply an overall poorer prognosis.

Unlike SARS and MERS -- where initial chest imaging abnormalities are more frequently unilateral -- COVID-19 is more likely to involve both lungs on initial imaging.

"To our knowledge," Hosseiny et al. continued, "pleural effusion, cavitation, pulmonary nodules, and lymphadenopathy have not been reported in patients with COVID-19."

Ultimately, the authors of this AJR article recommended CT for follow-up in patients recovering from COVID-19 to evaluate long-term or even permanent pulmonary damage, including fibrosis -- as seen in SARS and MERS infections.

https://www.sciencedaily.com/releases/2020/02/200228142018.htm