E-Paper
Covid-19: Vaccine candidates and therapies and where they stand
The race to develop a vaccine for Covid-19 is moving ahead at an unprecedented pace, with over 150 candidates in development and some two dozen candidates already being tested in people.
The coronavirus disease (Covid-19) roared back as the world reopened after spending months under lockdown. This underscored an urgent need for treatment and vaccines.
Billionaire and Microsoft co-founder Bill Gates has said that normalcy will come only when second generation of Covid-19 vaccine will be rolled out. The World Health Organisation (WHO), meanwhile, believes that a Covid-19 vaccine will be ready for registration by the end of 2020 or early next year at the earliest.
The virus that was first detected in China late last year has now touched nearly every corner of the globe. As of October 12, 37.7 million had been infected by Covid-19.
The race to develop a vaccine is moving ahead at an unprecedented pace, with over 150 candidates in development and some two dozen candidates already being tested in people, according to news agency Reuters. However, there are still no word on a vaccine’s availability.
Here are some of the drugs, therapies and vaccines under development to fight Covid-19:
Remdesivir: The antiviral drug given by infusion previously failed as an Ebola treatment but showed promise against certain coronaviruses in animal studies. In a randomised trial, remdesivir led to significant reduction in recovery time of hospitalised patients compared with a placebo, demonstrating that it does impact Sars-CoV-2, the virus that causes Covid-19. More than a dozen trials are underway in China, Europe and the United States with positive results starting to emerge.
Hydroxychloroquine (HCQ): The HCQ is widely used for treating malaria, but it has now been found to have anti-viral as well as anti-inflammatory activity. During trials, the HCQ successfully blocked the novel coronavirus’ entry into cells. Subsequent studies have found little benefit in patients treated with the drug. Health experts caution that HCQ should never be used without a prescription and could lead to dangerous side effects. Dozens of clinical trials to assess benefits of the drug to Covid-19 patients are ongoing, but several major trials were halted following a safety warning by the World Health Organisation (WHO) in May.
Aspirin, Clopidogrel (Plavix), Rivaroxaban (Xarelto), Atorvastatin (Lipitor), Omeprazole (Prilosec): These have been put under trial in the United Kingdom. The drugs try to mitigate the effect of Covid-19 on heart muscles. These cardioprotective drugs will be tried on 3,000 patients in the UK, with a completion date of March 30, 2021.
BCG tuberculosis vaccine: Bacillus Calmette-Guerin tuberculosis vaccine induces a broad innate immune-system response, which has been shown to protect against infection or severe illness with other respiratory pathogens. Large trials of the drug were conducted in Australia and the Netherlands to understand its efficacy in fighting the vius that causes Covid-19. In a small trial in the United Arab Emirates, none of the 71 hospital staff who received a BCG booster shot in early March had been infected with the virus by late June, compared with 18 of 201 staff who did not receive the vaccine and tested Covid-19 positive.
Convalescent plasma: This is a method which is being considered by health experts to treat Covid-19. Blood plasma from recovered Covid-19 patients is transfused into patients who are currently ill, in the hope that freshly-made antibodies will help fight the virus. The method has been used for more than 100 years and carries little risk of harm or side effects. In Delhi, the government led by Arvind Kejriwal has opened centres where plasma is donated. Kejriwal has also urged people of Delhi to come out in large numbers to donate the plasma which can then be used to treat patients suffering from Covid-19.
NKG2D-ACE2 CAR-NK cells: The non-drug therapy pairs NKG2D receptor for the immune system’s natural killer (NK) cells that play a major role attacking foreign invaders like cancer or viruses, with the ACE-2 receptor that the coronavirus uses to enter human cells. The therapy is being tested by Chinese firm Chongqing Sidemu Biotechnology Technology Co Ltd. More than 90 patients are undergoing tests to know whether this cell therapy can prevent the Sars-CoV-2 virus from entering cells and multiplying.
(With inputs from Reuters)
