While the pandemic is still ongoing, we continue to round up the scientific studies that offer encouraging results to help us envisage an end to the current crisis.
Firstly, scientists at the Gamaleya Research Institute of Epidemiology and Microbiology, in Moscow, devised a vaccine that elicits a robust immune response, with no serious side effects in humans.
The Russian vaccine, known as Sputnik V, uses a modified version of an adenovirus that causes the common cold. Denis Logunov, the study’s first author and head of the research lab at Gamaleya, explains how it works.
“When adenovirus vaccines enter people’s cells, they deliver the SARS-CoV-2 spike protein genetic code, which causes cells to produce the spike protein. This helps teach the immune system to recognize and attack the SARS-CoV-2 virus,” Logunov says.
The researchers assessed the vaccine in a small phase 1 and 2 trial that lasted 42 days and included 38 healthy participants aged 18–60.
At this point in the study, the scientists wanted to assess the vaccine’s safety and its ability to elicit an immune response, rather than whether it can prevent infections with the new coronavirus.
The results showed a strong immune response in the participants. They developed antibodies and more advanced immune responses, similar to T cell reactions. T cells are white immune cells — some of which, called killer T cells, can find and kill infected cells.
The Russian vaccine was also found to be safe and did not elicit any serious side effects. Next, the team plans to enter phase 3 of the trial, which will involve 40,000 participants.
Japanese-based scientists from Osaka University and Osaka Habikino Medical Center believe they could repurpose an arthritis drug to treat severe COVID-19.
The team began their research by focusing on cytokines, proteins secreted by immune cells, with key immunomodulatory functions. They aimed to understand their role in cytokine storms — the immune system phenomenon that may lead to fatal outcomes in COVID-19.
With this in mind, the scientists studied the cytokine profiles of 91 patients with cytokine storms due to “bacterial sepsis, acute respiratory distress syndrome, or burns.”
After focusing on various interleukins — a type of cytokine — the scientists found a rise in interleukin-6 (IL-6) early in the disease process, which piqued their interest.
In turn, this increase in IL-6 triggered a rise in a protein called PA-1, which leads to blood clotting.
So, the scientists gave participants injections of the antibody-based drug tocilizumab (Actemra), which blocks IL-6 signaling.
When people with severe COVID-19 received tocilizumab, their levels of the blood clotting PA-1 protein decreased. Also, the drug eased symptoms and improved critical illness for these patients.
Researchers from Washington University School of Medicine in St. Louis (WUSTL) have devised a new intranasal vaccine, tested in mice with COVID-19.
Similar to the Russian vaccine, WUSTL’s counterpart also uses a modified adenovirus inserted with the coronavirus’ spike protein.
In mice, one vaccine dose protected against infection with SARS-CoV-2.
Speaking to MNT about their findings, senior study author Prof. Michael S. Diamond explained that the intranasal vaccine would not use a live form of the virus. This made it safer than other vaccines administered through the nose, such as the regular influenza vaccine.
“In these mouse models, the vaccine is highly protective. We’re looking forward to beginning the next round of studies and ultimately testing it in people to see if we can induce the type of protective immunity that we think will not only prevent infection but also curb pandemic transmission of this virus,” said Prof. Diamond.
“Any vaccine can cause side effects,” he continued. “However, because the vaccine does not replicate, it could not cause unanticipated infection the way a ‘live’ vaccine could — in this way, it would be safer.”
“We will soon begin a study to test this intranasal vaccine in nonhuman primates with a plan to move into human clinical trials as quickly as we can.”
— Prof. Michael S. Diamond
After much debate, a review pooling data from 19 studies concludes that long-term use of hypertension drugs, known as ACE2 inhibitors, might lower the risk of severe illness from the new coronavirus.
Since the beginning of the pandemic, the role of these drugs has been controversial. Some researchers suggest they might worsen outcomes, while other studies show no effect on infection severity.
The review, which is the largest meta-analysis on the subject, found that COVID-19 patients with high blood pressure who took the drugs were 33% less likely to die or have severe illness than patients with hypertension who did not take them.
Lead researcher Dr. Vassilios Vassiliou, of the Norwich Medical School at the University of East Anglia, United Kingdom, comments on the findings.
He says, “[T]he important thing we showed was that there is no evidence that these medications might increase the severity of COVID-19 or risk of death,” says Dr. Vassiliou.
“On the contrary, we found there was a significantly lower risk of death and critical outcomes, so they might, in fact, have a protective role — particularly in patients with hypertension.”
– Dr. Vassilios Vassiliou
He continues: “As the world braces itself for a potential second wave of the infection, it is particularly important that we understand the impact that these medications have in COVID-19 patients. Our research provides substantial evidence to recommend continued use of these medications if the patients were taking them already.”