Since the beginning of the SARS-CoV-2 epidemic in January 2020, almost 3.9 million people have fallen ill and approximately 270,000 have died. Across the world, scientists are working on new vaccines against the virus and drugs which could help in COVID-19, the disease caused by SARS-CoV-2.
In opposition to previous news leaked from part of a report on the World Health Organisation’s (WHO) website, that remdesivir had no benefits from using it in patients with COVID-19; on Wednesday, 29th April 2020 scientists from US National Institutes of Health announced that their trial is known as “Adaptive COVID-19 Treatment Trial (ACTT)” sponsored by National Institute of Allergy and Infectious Diseases has shown that remdesivir accelerates recovery from advanced COVID-19. Hospitalized patients with advanced COVID-19 and lung involvement who received remdesivir recovered faster than similar patients who received placebo. This data is according to a randomized, controlled trial involving 1603 patients, which began on February 21. This was the first clinical trial launched in the United States to evaluate an experimental treatment for COVID-19.
Preliminary results indicate that patients who received remdesivir had a 31% faster time to recovery compared to those who received placebo (p<0,001). Specifically, the median time to recovery was 11 days for patients treated with remdesivir compared to 15 days for those who received a placebo. Results also suggested a survival benefit, with a mortality rate of 8.0% for the group receiving remdesivir versus 11.6% for the group receiving placebo.
Furthermore, the European Medicines Agency (EMA) started a rolling review of remdesivir related data for COVID-19. A rolling review is one of the regulatory tools available to the EMA, to speed up the assessment of a promising investigational medicine drug during a public health emergency. This decision of EMA is based on preliminary results from the ACTT study, which suggests a beneficial effect of remdesivir in the treatment of hospitalized patients with mild-to-moderate or severe COVID-19. However, EMA claims, they have not yet evaluated the full study and it is too early to draw any conclusions regarding the risk-benefit balance of the remdesivir.
On 1st May 2020, the US Food and Drugs Administration issued an emergency use authorization for the remdesivir for the treatment of suspected or laboratory-confirmed COVID-19 in adults and children hospitalized with severe disease. The emergency use authorization allows for remdesivir to be distributed in the U.S. and be administered by healthcare professionals for patients with severe disease. Severe disease is defined as patients with low blood oxygen levels, needing oxygen therapy, or more intensive breathing support such as a mechanical ventilator.
On 30th April 2020, WHO has released the next update on the draft on potential candidate vaccines against SARS-CoV-2. Comparing this to the previous, there are 8 potential vaccines that have started clinical trials, where 3 of them are traditional vaccine types and 5 are developed on new technology platforms ie. non-replicating viral vector or nucleic acids.
The inactivated vaccines contain selected viral proteins or inactivated viruses that have to be killed prior to use. The dead viruses can no longer multiply, but the body still recognizes them as an intruder, so the body’s immune system still can generate the defense response and produce antibodies. The vaccinated individual, therefore, does not develop the disease. All currently presented vaccine candidates are inactivated viruses and parts of the viruses.
Sinovac Biotech Co., Ltd. previously tested their vaccine on eight rhesus macaques. The vaccine in development has protected the animals from infection of SARS-CoV-2. Scientists gave them two different doses of their vaccine and then three weeks later, the group introduced SARS-CoV-2 into the monkey’s lungs through tubes down their tracheas. None of the primates developed a full-blown infection, but the monkeys given the highest dose of the vaccine had the best response. Seven days after the animals received the virus, researchers could not detect it in the pharynx or lungs of any of them.
The research on the drugs and vaccines which could be helpful against SARS-CoV-2 and COVID-19 are in a much more advanced stage than we observed two weeks ago or one month ago. Experts have said that whilst the coronavirus vaccine could probably be available within 12 to 18 months (because the vaccine needs to be tested), “herd immunity” will take much longer. It is more likely that clinical trials on the drugs i.e. Remdesivir will finish much earlier and prior to a tested and commercially available vaccine.