New Delhi: Scientists and drugmakers all over the world are racing against time to find a safe and effective vaccine against COVID-19, the disease caused by the novel coronavirus (SARS-CoV-2).
While there isn’t yet an approved COVID-19 vaccine for widespread use, a handful of candidates are already in the final stage of testing with some of them declaring positive interim results from phase 3 trials.
On November 11, US drug giant Pfizer and its German partner BioNTech announced that their mRNA-based coronavirus vaccine was found to be more than 90 per cent effective in preventing COVID-19.
Earlier this week, another US biotech firm Moderna said that its experimental vaccine against the SARS-CoV-2 virus demonstrated 94.5 per cent efficacy. While scientists and health researchers have welcomed the first compelling results suggesting that we might soon have a vaccine against COVID-19, a few key questions remain open – such as safe storage and handling of the vaccines, duration of protection of the vaccines, essential characteristics of a good vaccine, etc.
According to Adar Poonawalla, the CEO of Serum Institute of India, a good vaccine has four features. Taking to Twitter, the head of the Pune-based firm revealed that a good vaccine has to be safe, it should offer long-term protection against targeted disease, it should be transported and stored at a manageable temperature, and affordable to all of humanity.
Basically, vaccines work by training and preparing the body’s immune system to fight off the viruses and bacteria they target.
Both Pfizer and Moderna’s vaccines, which are waiting for the approval of the regulatory body, are based on mRNA technology. The new platform, mRNA, is faster to produce than traditional vaccines and effectively turn human cells into vaccine factories. But experts have raised concerns about the distribution challenges linked with Pfizer’s vaccine due to its specialised storage requirements. Pfizer’s vaccine would need needs minus 70 degrees Celsius temperature, which could complicate chain logistics, particularly in developing countries.
Moderna said their vaccine can be stored at refrigeration temperatures for 30 days, easing distribution woes for governments and agencies across the world – if and when the jab becomes available.
However, how long-lasting the protection will be from either the Moderna or Pfizer vaccines is not clear yet. Moreover, it is not yet clear how well they work for the elderly, the age-group at the highest risk from COVID-19 infection.
Meanwhile, Serum Institute had teamed up with AstraZeneca for the production of coronavirus vaccine developed by Oxford University. The vaccine candidate, dubbed ‘Covishield’ in India, is currently in the phase 2/3 clinical trials in the country. Recently, Poonawalla had hinted that India may get 100 million doses of the vaccine, which will be priced at Rs 224 per dose, by December.