(Reuters) - The following is a roundup of some of the latest scientific studies on the novel coronavirus and efforts to find treatments and vaccines for COVID-19, the illness caused by the virus.
Johnson & Johnson vaccine advancing through clinical trials
An experimental COVID-19 vaccine from Johnson & Johnson produced protective antibodies against the novel coronavirus in 90% of 805 volunteers by 29 days, and that increased to 100% by day 57, according to data from an ongoing mid-stage study. Side effects such as fever, muscle aches and injection site pain resolved quickly, researchers reported on Wednesday in the New England Journal of Medicine. To be approved by regulators, the J&J vaccine must show efficacy as reflected by a lower risk of infections and severe disease in study participants who receive it compared to those who do not. Efficacy data from a large late-stage trial on the vaccine is due by February. Experts expect the vaccine to show efficacy at or above 80%, which would exceed the 50% benchmark for regulatory approval but trail the roughly 95% achieved in trials of already-authorized vaccines from Moderna Inc and Pfizer Inc with BioNTech SE. The J&J vaccine requires just a single dose, and it does not have the cold storage requirements of the other vaccines. The likelihood of good results "hopefully is very high," the New Brunswick, New Jersey-based company's chief scientific officer Paul Stoffels said this week. (bit.ly/2LpBhHm)
COVID-19 gives some immunity, and reinfections 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 among 6,614 previously infected people, according to researchers leading a large ongoing study of healthcare workers in Britain. But when people do get COVID-19 a second time, they often have no symptoms, and so they may still be able to carry the coronavirus in their nose and throat and unwittingly pass it on, the researchers wrote in a report published on Wednesday by Public Health England (PHE) ahead of peer review. Experts have said people who contracted COVID-19 in the pandemic's first wave may now be vulnerable to infection again. "We now know that most of those who have had the virus, and developed antibodies, are protected from reinfection, but this is not total and we do not yet know how long protection lasts," said study leader Susan Hopkins, senior medical adviser at PHE in London. "If you believe you already had the disease and are protected, you can be reassured it is highly unlikely you will develop severe infections. But there is still a risk you could acquire an infection and transmit (it) to others." (bit.ly/3ihkuBZ; reut.rs/3ieWorA)
Coronavirus targets cells’ energy engines
Researchers have discovered an important line of attack used by the novel coronavirus: it targets an infected cell's mitochondria. These tiny organelles not only generate the energy that powers a cell's biochemical reactions, but they also play important roles 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. "Now we can say, when the virus attacks cells, it damages the mitochondria." In test tube experiments, the researchers found that the virus caused "dramatic changes and impairment" in the genes that regulate mitochondrial function, Cohen told Reuters. The implication, Cohen said, is that energy production in the cells and so-called innate immunity - the body's first line of defense against germs - are then impaired. Another implication is that having healthy mitochondria would help people combat the virus if they do become infected. "We know that a healthy diet and healthy lifestyle promote mitochondrial health," Cohen said, whereas mitochondrial function deteriorates with age and with many chronic conditions including diabetes and heart disease. In the future, Cohen added, researchers may develop COVID-19 interventions to help improve mitochondrial health. (go.nature.com/3bFlCyc)
‘Nanobody’ combos block coronavirus, even when it mutates
Combining small antibodies called nanobodies into single molecules to fight the novel coronavirus may be more effective than targeting it with conventional antibodies or single nanobodies, according to a new study. These "multivalent" nanobodies - containing multiple nanobody building blocks - "are substantially better in neutralizing viruses" and preventing them from breaking into cells, study leaders Florian Schmidt and Paul-Albert König of the University of Bonn told Reuters. The fused nanobodies "help each other so that the outcome is better than just the sum of the two responses." The nanobody constructs can target multiple sites on the coronavirus, making it harder for the pathogen to develop mutations that render treatment ineffective, according to a report published on Tuesday in the journal Science. While the researchers saw plenty of mutations that allowed the coronavirus to "escape" the effect of a single nanobody, "we did not find any escape mutants that were able to replicate in the presence of those nanobodies that target two different surfaces at the same time," Schmidt and König said. A spin-off company of the University of Bonn, called DiosCURE, expects to start testing the combined nanobody molecules in people later this year. (bit.ly/3nOvXKH)
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Reporting by Nancy Lapid and Kate Kelland; Editing by Will Dunham
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