Researchers from Estonia and Norway have established numerous treatment options to address the current COVID-19 pandemic. Using cell culture tests, the scientists were able to examine antibody-loaded plasma, medications, and drug combinations in the laboratory. They discovered a combination of two drugs that gave off exquisite results that they hope to start clinical trials on immediately.
In detail, the researchers were able to describe six already existing safe broad-spectrum antivirals that proved to be effective against COVID-19 in laboratory tests. They also found that the use of antibody-filled plasma from recovered coronavirus patients may only work if the donor recovered from the disease just recently.
According to Svein Arne Nordbø, one of the paper's authors from the Department of Medical Microbiology at St. Olavs Hospital, the treatment may not work if the blood collected was two months after the donor recovered from the illness.
Nevertheless, they remain optimistic as Magnar Bjørås, a professor in the Norwegian University of Science and Technology's Department of Clinical and Molecular Medicine, claims the data they have gathered brings excitement to the coronavirus treatment research playing field.
The full findings of the study were published in the journal Viruses on June 13, 2020.
New Drug Combo: Nelfinavir-Amodiaquine
The team used cell culture tests to grow the virus causative of COVID-19, SARS-CoV-2 essentially. The culture permitted them to test the efficiency of various drugs in the laboratory. They used a cell type called Vero-E6, which they found was suitable to reproduce the coronavirus.
Furthermore, they were able to examine 136 medications using the cell culture. The six drugs that acted agreeingly in their study were amodiaquine, emetine, homoharringtonine, nelfinavir, obatoclax, and salinomycin.
According to Denis Kainov, a senior author of the study, the drug combination that gave off the highest synergy was amodiaquine and nelfinavir. He adds that the orally available drug combo effectively inhibits the virus infection in cell cultures.
Moreover, the team believes it should be tested in clinical trials and pre-clinical studies as soon as possible. They also want to explore more on the efficiency of using blood plasma from COVID-19 survivors to treat those who are still battling with the disease.
Convalescent Serum From Recovered Coronavirus Patients
According to the study's researchers, the Vero-E6 cell line allied them to establish a "neutralizing antibody" test. The antibody test could also help determine the durability of antibodies from the plasma of coronavirus-recovered individuals.
Nordbø points out that if the convalescent serum is used for treatment, the serum must contain enough antibodies capable of inactivating the virus.
He says that the only way to know if the convalescent serum is capable enough is by adding dilutions to a live virus strain. Afterward, the mixtures on cell lines that can propagate the virus must be tested. He explains that neutralization tests remain to be the most specific.
They were able to confirm from previous studies that some patients who recovered from the virus did not produce a lot of antibodies at all. Furthermore, they also saw that the more recent the recovery from COVID-19, the more effective the serum was.
Nordbø concludes that clinicians need to collect plasma for treatment purposes as soon as patients recover from COVID-19. He adds that time is of the essence since the amounts of antibodies lessen with time.
