Coronavirus vaccine: Pfizer to Johnson &Johnson single-dose vaccine, all vaccines expected to arrive in India

While coronavirus vaccination drives have picked up pace in India, there's still a long way to go before every eligible Indian is vaccinated against COVID-19.

The Drugs Controller General of India (DGCI), has decided to do away with clauses that required specific, repeat trials of COVID-19 vaccines approved by international regulators, thus allowing for faster entry and usage of globally approved vaccines in India, which is battling a devastating surge of virus and facing acute vaccine shortage as well.

READ: Differences between Covaxin and Covishield, what you need to know

With the relaxation of norms, it is now being expected that many foreign contender vaccines, which have secured regulatory nods in respective countries will be allowed to be marketed in India as well.

Currently, there are two vaccines being used to inoculate people in India, the homegrown vaccine, Covaxin, which has been produced by Bharat Biotech and Covishield, the Oxford-Astrazeneca vaccine which has been produced and marketed by Serum Institute of India. Russia's Sputnik V availability, and other internationally approved vaccines are rumoured to be publically made available as well. Here's a quick look at all national, and international vaccines coming our way soon:

One of the first vaccines to be pushed into development, the Oxford-Astrazeneca, sold under the name of Covishield, is still the most widely used vaccine in India. Regulatory approvals were granted in late December. With an efficacy rate of over 71%, Covishield (also sold internationally as Vaxveria) has been approved for use by at least 4 big agencies- WHO, UK Healthcare Board, European Medical Union and used in many countries.

The vaccine is being exclusively marketed by the Pune-based Serum Institute of India (SII) which has ramped up production facilities to meet the need.

While the vaccine, which works as a two-dose regime was to be administered 4-6 weeks apart, recent recommendations have pushed for a wider gap, allowing upto a 12-week gap between doses.

READ MORE: Why the increase in Covishield doses is good news for India.

Sputnik V, developed and manufactured in Russia was first approved for use in the Soviet nation in the month of August. It was officially green-lighted for use in India after medical authorities granted emergency use approval in February 2021 based on the interim data collated from Russia.

The first doses of the Sputnik V vaccine arrived in India in the first week of May, with jabs being expected to roll out starting the third week of June. Strategic deals have been signed with the private manufacturer, Dr. Reddy's to ramp up production and administration of doses going forward.

Sputnik V, which contains a weakened strain of the virus works as part of a two-dose regime, wherein the two doses contain two different viral vectors. Clinical studies have suggested that the vaccine prompts a whopping 91.6% efficacy rate, which is much higher than other traditional vaccines.

Meanwhile, Sputnik Light, which is a single-dose version of the Russian vaccine, is also being considered for approval in the coming weeks. Upon nod, it will become the first single-shot COVID-19 vaccine to be used in India.

Pfizer-BionTech, a leading vaccine and medicine maker globally is all set to enter the Indian market with is a highly talked about and efficacious mRNA vaccine. The company is said to have signed strategic deals with the government to supply close to 5 crore vaccine doses to India between July and October. The company is also in talks to sign an 'indemnity clause which will free the vaccine maker of the liability of adverse reactions and potential side effects.

Pfizer's mRNA vaccine shot, which has already been approved for use in leading countries like UK, USA, Canada, Brazil, Israel, Australia, Japan and Singapore is considered to be highly effective and novel, with its unique messenger mRNA technology that instructs cells to produce a spike protein similar to SARS-COV-2's and launch defensive action. The vaccine is also delivered as a two-dose regime, spaced 21-28 days apart.

Pfizer's vaccine, which has also been approved for use in kids aged between 12-18 in select countries may also pave the way for kids' vaccination in India. However, the logistical hurdles of the vaccine- including the pricing and storage may require ramped up infrastructure as well.

Moderna, which, too, is an mRNA vaccine like Pfizer has been approved for use in select countries and carries strong odds of protection. As per reports, the vaccine maker, which is in high demand worldwide is also expected to seek fast-track approvals in India after laws over regulatory authorisation were relaxed. Industry reports mention that Indian drugmaker Cipla may form a strategic partnership with Moderna Therapeutics to bring over its innovative COVID-19 vaccine by 2022.

As per figures, Moderna's mRNA model provides 94% efficacy in preventing symptomatic COVID and reducing the severity of the infection. There is also some evidence to suggest that the vaccine would be able to prevent asymptomatic transmission as well, which made it win FDA nods. The 2-3 week wait, just like for Pfizer, works well for Moderna's COVID vaccine offering as well.

Serum Institute of India, which is spearheading Covishield manufacturing, is also overseeing 'at-risk' production of US-based Novavax vaccine in India. To be sold under the name of Covovax, the protein subunit vaccine is also expected to be fast-tracked for use later this year. Trials for the same were kickstarted in India in November 2020.

However, it should be noted that Novavax has not yet been approved for use in any of the countries worldwide. While the company has submitted review data to leading medical boards globally, the company is said to seek emergency use approvals by July, which will then allow SII to seek expedited grants.

The vaccine, which has been developed under a novel approach, has been found to be promising, carrying over 94.6% efficacy in early clinical trials. The protein technology used to make Novavax is also considered to be one of the safest and effective ones in the medicine world.

Janssen coronavirus vaccine, which is a single-shot vaccine produced by US-major Johnson and Johnson LLC is also expected to be cleared for use in India in the following months.

While Jannsen is one of the first single-shot coronavirus vaccines developed so far (apart from Sputnik Light), it was given emergency use nods in the US and most recently, the UK upon findings surfacing from clinical trials, which showcased that the vaccine delivered strong efficacy rate, at par with competitors. Reports have suggested that the central government is looking for speedy ways to import doses of the vaccine which could be used to inoculate the masses in a faster man