Progress has been reported on the one-dose J&J vaccine; COVID-19 reinfections are considered rare

(Reuters) – The following is a summary of some of the latest scientific studies on the new coronavirus and efforts to find treatments and vaccines against COVID-19, the disease caused by the virus.

The Johnson & Johnson vaccine is advancing through clinical trials

A Johnson & Johnson COVID-19 experimental vaccine produced protective antibodies against the new coronavirus in 90% of 805 volunteers over 29 days and increased to 100% on day 57, according to data from a mid-phase study. Side effects such as fever, muscle aches and pain at the injection site resolved quickly, researchers in the New England Journal of Medicine reported Wednesday. To be approved by regulators, the J&J vaccine must show efficacy as reflected in a lower risk of serious infections and disease in study participants who receive it compared to those who do not. The efficacy data of a large final phase trial on the vaccine are due to be published in February. Experts expect the vaccine to show an efficacy greater than or equal to 80%, which would exceed the reference 50% for regulatory approval, but will follow approximately 95% achieved in already authorized vaccine trials of Moderna Inc and Pfizer Inc with BioNTech SE The J&J vaccine requires only a single dose and does not meet the cold storage requirements of other vaccines. The likelihood of good results “is expected to be very high,” New Brunswick-based scientific manager Paul Stoffels, based in New Jersey, said this week. (bit.ly/2LpBhHm)

COVID-19 provides some immunity and infections are considered rare

COVID-19 survivors are very likely to have some immune protection against the virus for at least five months, and reinfections in recovered patients are rare, only 44 cases were found among 6,614 previously infected people, according to researchers conducting a large study continuous health workers in Britain. But when people receive COVID-19 for the second time, they often show no symptoms and can therefore continue to carry the coronavirus in their nose and throat and transmit it unintentionally, the researchers wrote in a report released Wednesday by Public Health England (PHE) ahead of peer review. Experts have said that people who contracted COVID-19 in the first wave of the pandemic could now be vulnerable to infection again. “We now know that most of those who have had the virus and developed antibodies are protected against reinfection, but that’s not total and we still don’t know how long the protection lasts,” said study leader Susan Hopkins, an advisor. PHE senior physician in London. “If you think you already have the disease and are protected, you can be reassured that you are very unlikely to develop serious infections. But there is still the risk that you may acquire an infection and pass it on to others.” (bit.ly/3ihkuBZ; reut.rs/3ieWorA)

The coronavirus targets the energy engines of cells

Researchers have discovered an important line of attack used by the new coronavirus: it targets the mitochondria of an infected cell. These tiny organelles not only generate the energy that boosts the biochemical reactions of a cell, but also play an important role in immune function. “We knew that when the virus attacks cells bad things happen, but we didn’t know why,” said Dr. Pinchas Cohen of the University of Southern California, whose team published its findings this month in the journal Scientific Reports. “We can now say that when the virus attacks cells, it damages the mitochondria.” In experiments with test tubes, the researchers found that the virus caused “dramatic changes and deterioration” in the genes that regulate mitochondrial function, Cohen told Reuters. The implication, Cohen said, is that energy production in cells and so-called innate immunity (the body’s first line of defense against germs) are impaired. Another implication is that having healthy mitochondria would help people fight the virus if they become infected. “We know that a healthy diet and a healthy lifestyle promote mitochondrial health,” Cohen said, while mitochondrial function deteriorates with age and with many chronic conditions, including diabetes and heart disease. In the future, Cohen added, researchers could develop COVID-19 interventions to help improve mitochondrial health. (go.nature.com/3bFlCyc)

“Nanobody” combos block the coronavirus, even when mutated

Combining small antibodies called nanocodies into individual molecules to fight the new coronavirus may be more effective than targeting it with conventional antibodies or individual nanocodies, according to a new study. These “multivalent” nanocodies, which contain multiple nanocode building blocks, “are substantially better at neutralizing viruses” and preventing them from breaking into cells, study leaders Florian Schmidt and Paul-Albert König told Reuters , from the University of Bonn. Fused nanocodies “help each other so that the result is better than the sum of the two responses.” Nanocody constructs can target various coronavirus sites, making it more difficult for the pathogen to develop mutations that make treatment ineffective, according to a report published Tuesday in the journal Science. Although the researchers saw many mutations that allowed the coronavirus to “escape” from the effect of a single nanocosus, “we did not find any escape mutants that were able to replicate in the presence of these nanoscopes that they run on two different surfaces at the same time, ”Schmidt and König said. A company derived from the University of Bonn, called DiosCURE, hopes to start testing the combined nanocole molecules in people later this year. (bit.ly/3nOvXKH)

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