In a retrospective study of patients tested for COVID-19, researchers at the University of Chicago Medicine found an association between vitamin D deficiency and the likelihood of becoming infected with the coronavirus.

"Vitamin D is important to the function of the immune system and vitamin D supplements have previously been shown to lower the risk of viral respiratory tract infections," said David Meltzer, MD, PhD, Chief of Hospital Medicine at UChicago Medicine and lead author of the study.

A new international study published today has shown that treating critically ill patients with COVID-19 with the steroid hydrocortisone improves their chances of recovery.

The study, led in the UK by Professor Anthony Gordon from Imperial College London with collaborators from the Intensive Care National Audit & Research Centre, found that patients receiving intensive care who were treated with a regular fixed dose of the steroid hydrocortisone for seven days had a better chance of recovery, compared with the patients who were not treated with the steroid.

On March 28, the Food and Drug Administration (FDA) exercised its Emergency Use Authorization (EUA) authority to allow the use of hydroxychloroquine for the treatment of COVID-19. On June 15, after a number of studies failed to find positive effects, the agency revoked this authorization. This chain of events raises questions about the speed, rigor and potential politicization of the authorization process. These actions also may have hurt the FDA's credibility and the public's trust in the agency, which could decrease the public's confidence in and adoption of eventual COVID-19 vaccines.

Researchers at the University of Alberta are preparing to launch clinical trials of a drug used to cure a deadly disease caused by a coronavirus in cats that they expect will also be effective as a treatment for humans against COVID-19.

"In just two months, our results have shown that the drug is effective at inhibiting viral replication in cells with SARS-CoV-2," said Joanne Lemieux, a professor of biochemistry in the Faculty of Medicine & Dentistry.

An extensive search and testing of current drugs and drug-like compounds has revealed compounds previously developed to fight SARS might also work against COVID-19.

Using the National Drug Discovery Centre, researchers from the Walter and Eliza Hall Institute identified drug-like compounds that could block a key coronavirus protein called PLpro. This protein, found in all coronaviruses, is essential for the virus to hijack and multiply within human cells, and disable their anti-viral defences.

In the transmission of signals within the cell which, for example, stimulate cell growth or trigger metabolic processes, phosphate groups play an important biochemical role. The phosphate groups are often attached to proteins or removed to control activity. In this process, a change in the protein triggers the next one and the signal is transmitted in a signaling cascade. The target is usually the cell nucleus, where genes are switched on or off.

Scientists at Washington University School of Medicine in St. Louis have developed a vaccine that targets the SARS-CoV-2 virus, can be given in one dose via the nose and is effective in preventing infection in mice susceptible to the novel coronavirus. The investigators next plan to test the vaccine in nonhuman primates and humans to see if it is safe and effective in preventing COVID-19 infection.