Coronavirus vaccine: Russia's Sputnik vaccine gets approved for use, here's how it fares against Covaxin and Covishield

Amidst a bad surge in COVID-19 cases in India, the third COVID-19 vaccine, Sputnik V has just been approved for emergency use authorization in the country. The news comes at a time when India's battling a high surge of cases and centres are running short of vaccine supplies.

Sputnik V, which was the first COVID-19 vaccine to be officially registered for use in August 2020 has already been approved for use in many countries worldwide. Regulatory testing, nods for use in India were greenlighted in November 2020.

Hyderabad based Dr Reddy's, the official licensing partner of the vaccine in India will start importing doses of the vaccine from May. According to rumoured reports, the company will secure 250 million doses of the vaccine for use in India.

Any vaccine approved for use right now suffices enough safety reports and has secured WHO nods. Yet, ever since the vaccine was first rolled out for use, the Sputnik V vaccine has been surrounded by added controversies.

While the availability of Sputnik V will definitely speed up COVID vaccination in India, how effective would it really be?

Where does it stand in comparison to the two vaccines already in use- Covaxin and Covishield? We brief you with an explainer on the same...

Russia's Sputnik V vaccine, developed via a prototype modelled by the Gamaleya Institute was officially approved for use in India after the Drugs Comptroller General of India issued emergency authorization based on the success of clinical results in Russian labs.

Dr Reddy's, who will sell and market the vaccine in India, was also in talks to conduct mass-scale clinical trials in India. As part of the study, a trial was also conducted on 1300 participants in India.

RDIF, which is producing the vaccine is also in partnership with five other Indian companies to manufacture over 800 million doses for export.

While sources suggest that the vaccine, right now, has been approved for use in restricted parts in India, as of April 12, 2021, a total of 62 countries have granted regulatory approvals for the use of the Sputnik V vaccine.

The DCGI granted necessary approvals for usage in India basis the interim results of the vaccine trials done in Russia, which showed a 91.6% rate. Studies done so far have also detailed that the vaccine was capable of mounting a 100% effective response against severe and moderate forms of the disease. A large scale study, which has been published in the Lancet also proved findings of the same to be well-suited and tolerable against the deadly pathogen. The efficacy right now matches Pfizer and Moderna's, which both carry over 90% efficacy rate.

In comparison to Russia's Sputnik V, both Covaxin and Oxford-Astrazeneca (Covishield) shot have a lower efficacy rate. While Bharat Biotech's Covaxin is still under study (Phase 3) is said to be at least 81% effective against the virus, and well-effective against the UK strain of the virus too.

As for Covishield which wrapped up clinical testing in December and being used globally, there is an efficacy rate of over 70.4 %. Further clinical studies also evaluated that the efficacy could be further pushed up to 90% if two doses are administered to beneficiaries.

It should be noted that all three vaccines have been proven to be efficacious, as per WHO standards and help minimize the risk of infection, symptomatic illness, severity and dreaded mortality.

Sputnik V, much like Oxford-Astrazeneca ( Covishield) and Covaxin is a traditional vaccine. It carries a weakened version of the common cold adenovirus strain, which resembles coronavirus but doesn't cause illness. Once the shot is injected, it prompts the immune system to generate necessary antibodies. Covaxin, meanwhile, makes use of an inactive version of the virus, which then triggers the immune system to mount a sufficient response. Since traditional vaccines have been brought into use for years now, they are considered to be a lot safer and reliable than mRNA vaccines.

Sputnik V, much like India's homegrown vaccines works as a two-dose regime. However, the timing of the second shot is to be injected 21 days after the first one, whereas Covaxin is to be administered 32 days after the first one, and Covishield given at a time gap of 4-6 weeks.

Sputnik V also uses two different vectors for the two jabs. This, as per experts cuts down the risk of immune system resistance and at the same time, could grant higher immunity to an individual.

Side effects pertaining to the vaccine are generally immune reactions when antibodies begin to generate.

Both Covaxin and Covishield are said to carry reactogenic side-effects, most of which are mild in nature, including tenderness in the arm, fever, muscle pain, fatigue, joint pain.

The recent discovery of blood clots in Europe, with the Oxford jab made many worries. However, the incidents were a rare occurrence and have not been ruled as an after-effect.

As for Sputnik V, no serious side effects have come to be associated with the vaccine. RDIF has also said that the vaccine tends to carry no side effects in general. However, from what is believed, some people can get a fever which could be overcome with OTC medications, home remedies. No other side effects, of allergies, have been linked to it by far.

Right now, experts say that full immunity sets in only after a person gets both shots of the vaccine. With Covaxin and Covishield, peak immunity may set in 4-5 weeks after getting the vaccine dose. With Sputnik V, peak immunity develops somewhere between Day 28 to day 42.

The pricing of the vaccines hasn't been fully disclosed yet. While both Covaxin and Covishield are available free of cost at government facilities and at a nominal fee at private hospitals, it is being reported that Covaxin will also be made available to the public at affordable rates.