In recent news, Pfizer, an American pharmaceutical company, has reported that its vaccine candidate BNT162b2 has shown over 90% effectiveness in preventing Covid-19 among participants who show no evidence of prior SARS-CoV-2 infection.
About BNT162b2
BNT162b2 is a single nucleoside-modified messenger RNA (modRNA) vaccine. It is created with a short segment of genetic material known as the messenger RNA or mRNA that provides instructions for human cells. These instructions guide the cells to produce a harmless version of a target protein, in this case, the spike protein of SARS-CoV-2. The purpose of this process is to trigger an immune response.
The mRNA Vaccine Approach
The vaccine utilizes a new approach to protect against viral infections. Traditional vaccines typically work by training the body to recognize and eliminate proteins produced by pathogens. However, instead of introducing these proteins, mRNA vaccines trick the patient’s immune system into producing the viral proteins itself. While these proteins are harmless, they can provoke a robust immune response.
Clinical Trials and Efficiency
The third phase of clinical trials for BNT162b2 commenced in July, involving 43,538 participants. By November, 38,955 of these participants had received a second dose. A case split between vaccinated individuals and those receiving a placebo indicates a vaccine efficacy rate above 90%, seven days after the second dose. This implies that protection is achieved 28 days after initiating the vaccination schedule, which consists of two doses.
Pfizer’s Announcement and Safety Concerns
Pfizer became the first company to release promising late-stage trial data for a potential Covid-19 vaccine. Despite this preliminary optimism, the announcement does not yet provide scientifically conclusive evidence regarding the safety and efficacy of the vaccine. However, an external independent Data Monitoring Committee (DMC) has not reported any serious safety concerns to date.
Seeking Emergency Use Authorization
The company plans to submit safety and efficacy data from the trial to the United States Food and Drug Administration (USFDA). This will be done in the days to come, seeking emergency use authorisation.
Global Vaccination Efforts
As of mid-October 2020, the World Health Organization (WHO) identified 42 candidate vaccines at the stage of clinical trials, up from 11 in mid-June. Ten of these were at the most advanced phase 3 stage. The USA biotech firm Moderna, several state-run Chinese labs, and a European project led by the University of Oxford and AstraZeneca are also progressing towards potentially viable vaccines.
Russian Vaccines
Two Russian Covid-19 vaccines have been registered for use before the completion of clinical trials. However, these have not been widely accepted outside of Russia.
India’s Progress in Vaccine Development and Administration
India is preparing to administer a vaccine against Covid-19 to its population early in 2021. For this purpose, it is currently collaborating with neighbouring countries on possible clinical trials of vaccine candidates. A team from the Indian Council of Medical Research (ICMR) and the Department of Biotechnology (DBT) under the Union Ministry of Science and Technology, has trained doctors and regulators in Sri Lanka, Myanmar, Bangladesh, Bhutan, Nepal, and Afghanistan.
Indigenously Developed Vaccines in India
ZyCoV-D, designed and developed by Zydus with support from the DBT, and Covaxin, developed by Bharat Biotech in collaboration with the ICMR, are among the vaccines developed indigenously in India.
Global Vaccine Collaboration
India is also aiding in global trials. Covishield, technically referred to as AZD1222 or ChAdOx 1 nCoV-19, is the Oxford-AstraZeneca Covid-19 vaccine candidate that India is involved with. Sputnik V, developed by Moscow’s Gamaleya Institute in collaboration with Russia’s defence ministry, was the first vaccine to be officially registered.
