Progress reported on the J&J single dose vaccine; COVID-19 reinfections seen as 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 for 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 up to 29 days and increased to 100% by day 57, according to a study in course in the middle of the stage. Side effects, such as fever, muscle aches and pain at the injection site, resolved quickly, the researchers reported Wednesday in the New England Journal of Medicine. To be approved by regulators, the J&J vaccine must demonstrate efficacy, as reflected in a lower risk of infection and severe disease in study participants who receive it than those who do not. Efficacy data from a large late-stage vaccine study will be published by February. Experts expect the vaccine to be 80% or more effective, which would exceed the 50% reference value for regulatory approval, but follows about 95% in already licensed vaccine studies from Moderna Inc. and Pfizer Inc. with BioNTech SE. The J&J vaccine requires only a single dose and does not have the cold storage requirements of the other vaccines. The likelihood of good results is “hopefully very high,” New Jersey scientific director Paul Stoffels of New Jersey said this week. (bit.ly/2LpBhHm)

COVID-19 confers some immunity and reinfection seen as rare

COVID-19 survivors are highly likely to have some immune protection against the virus for at least five months, and reinfections in recovered patients are rare, with only 44 cases found in 6,614 previously infected people, according to researchers conducting a large study Ongoing healthcare workers in the UK. But when people receive COVID-19 a second time, they often show no symptoms and therefore may be able 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) before peer review. Experts said people who contracted COVID-19 in the first wave of the pandemic could again be vulnerable to infection. “We now know that most people who have had the virus and developed antibodies are protected against reinfection, but this is not complete and we do not yet know how long the protection will last,” said study leader Susan Hopkins, PHE’s senior medical adviser in London. “If you think you already have the disease and are protected, you can rest assured that it is very unlikely that you will develop severe infections. But there is still a risk of getting an infection and passing it on to others.” (bit.ly/3ihkuBZ; reut.rs/3ieWorA)

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 organs not only generate the energy that fuels the biochemical reactions of a cell, but also play important roles in immune function. “I knew that when the virus attacks cells, bad things happen – but I didn’t know why,” said Dr. Pinchas Cohen of the University of Southern California, whose team published its findings this month in Scientific Reports. “Now we can say that when the virus attacks the cells, it damages the mitochondria.” In test tube experiments, the researchers found that the virus caused “dramatic changes and damage” to 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 then affected. 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 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” combinations block the coronavirus, even when it moves

Combining small antibodies called nanobodies into single molecules to fight the new coronavirus may be more effective than targeting it with conventional antibodies or nanobodies alone, according to a new study. These “multivalent” nanobodies – which contain several building blocks of nanobodies – “are substantially better at neutralizing viruses” and preventing them from breaking into cells, study leaders Florian Schmidt and Paul-Albert König of the University of Reuters told Reuters. Bonn. The fused nanobodies “help each other so that the result is better than just the sum of the two answers”. Nanobody constructs can target multiple 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. While the researchers saw a lot of mutations that allowed the coronavirus to “escape” the effect of a single nanobody, “we did not find any escape mutants that could reproduce in the presence of those nanobodies that target two different surfaces at the same time.” Schmidt and König, a spin-off company at the University of Bonn called DiosCURE, are expected to begin testing combined nanobody molecules in humans later this year (bit.ly/3nOvXKH)

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