Sputnik V vs Sputnik Light: Is a Single-Dose Vaccine Enough?

What’s the difference between Sputnik V and Sputnik Light? Here’s all you need to know.

4 min read
Sputnik V vs Sputnik Light: Is a Single-Dose Vaccine Enough?

As India grapples with a vaccine supply shortage amid a second wave, could a single-dose vaccine help?

On Thursday, 6 May, the Russian Direct Investment Fund (RDIF) announced that the country has authorised a one-shot COVID-19 vaccine called Sputnik Light to help nations with high infection rates. It could be the first single-dose vaccine in India, and Indian partners, such as Dr Reddy’s, are poised to meet with the government and the Drugs Controller General of India (DCGI) in June to discuss an immediate launch.

On Friday, 14 May, Kirill Dmitriev, Russia Direct Investment Fund CEO, said that Sputnik V Light is expected to launch in India soon.

What Is Sputnik Light?

Sputnik Light is the first component (recombinant human adenovirus serotype number 26 (rAd26)) of Sputnik V – this means it is the first dose of the Sputnik V vaccine.

Johnson and Johnson’s single-dose vaccine is also based on human adenovirus serotype number 26 (rAd26). However, this underwent larger phase 3 trials and is approved by the US and Europe and listed by WHO.


The vaccine is developed by Moscow's Gamaleya Institute and RDIF has said it has an efficacy of 79.4 percent.

“The single-dose Sputnik Light vaccine demonstrated 79.4 percent efficacy, according to analysed data taken from 28 days after the injection was administered as part of Russia’s mass vaccination programme between 5 December 2020 and 15 April 2021.”
RDIF’s Statement

This efficacy level is higher than that of many two-dose vaccines and can be an effective way to vaccinate large populations.

Meanwhile, a Phase III clinical trial with 7,000 people was done in Russia, the United Arab Emirates, Ghana and other countries, and interim results are expected this month, said RDIF.

The Gameleya Centre also claims it is effective against the new COVID-19 strains as per lab tests. The single-dose also costs $10.

“The single-dose regimen solves the challenge of immunising large groups in a shorter time, which is especially important during the acute phase of the spread of coronavirus, achieving herd immunity faster.”
Kirill Dmitriev, RDIF Head

Is a Single-Dose Vaccine Enough?

Experts have said that a single-dose vaccine could help inoculate more people in the same amount of time, but the long-term efficacy remains unclear until there is more clinical data.

Renowned virologist Dr Gagandeep Kang told MoneyControl,

“If any single-dose vaccine is licensed based on robust clinical efficacy data, we can accept it and do real-world evaluation of extent and duration of protection.”
Dr Gagandeep Kang

Besides, efficacy data from this single-dose vaccine is comparable to those of the two-dose Pfizer/BioNTech, Moderna or AstraZeneca (Covishield in India) vaccines.

However, Michael Breen, Director of Infectious Diseases and Ophthalmology at GlobalData Healthcare at GlobalData, clarified that Sputnik Light is a good choice for a shortage situation or to control an outbreak but is not “ideal".

He told MoneyControl, "It should be noted that these developers have not sought approval as a single-dose, and this is likely driven by the fact that long-term protection from a single dose is unclear, and likely not to be as durable as two doses. So, from a long-term standpoint, Sputnik Light is not ideal, but in terms of rapidly controlling the outbreak, with a second dose to come later, it's very promising."

All About Sputnik V

Sputnik V made waves for being the world’s first registered vaccine against coronavirus on 11 August 2020. Russia's COVID-19 Vaccine Sputnik V is developed by the Gamaleya National Research Institute of Epidemiology and Microbiology. The vaccine is based on the established human adenoviral vector platform.

As per Russian authorities, around 8 million Russians have been administered the Sputnik V vaccine and the country’s scientists announced in March that it is 97.6 percent effective against COVID-19 as per “real-world” data from 3.8 million people. The Lancet found Sputnik V to be 91.6 percent effective. In an interim analysis of the Phase III clinical trial, Sputnik V showed strong efficacy, immunogenicity, and safety results.

Sputnik V is one of only three clinically tested vaccines in the world (including Pfizer and Moderna) with an efficacy of 91.6 percent as per The Lancet’s findings.

Sputnik V started rolling out it's vaccines for public use in Russia in December 2020. This remains the main vaccine for Russia, while they aim to export Sputnik Light to countries in need. The vaccine is currently being administered for emergency use in 59 countries.


Sputnik V in India

Meanwhile, in India, the first shot of Sputnik V was administered in Hyderabad on Friday, 14 May. The maximum retail price of the imported vaccine is Rs 995.40 per dose.

“The vaccine has been registered in India under the emergency use authorisation procedure based on results of clinical trials in Russia as well as positive data of additional Phase III local clinical trials in India conducted in partnership with Dr Reddy’s Laboratories,” read a statement released by the company.

Spuntik V’s road to India:

In January, they received approval from the DCGI to conduct Phase III clinical trial for the Sputnik V vaccine.

In September 2020, Dr Reddy’s Laboratory partnered with RDIF to conduct clinical trials of the Sputnik V and for its distribution rights in India.

And in October, Dr Reddy’s signed an agreement to conduct Phase I and III bridging studies in India.

Other than Dr Reddy’s Laboratory, RDIF has tied up with a host of Indian pharmaceutical players such as Hetero Biopharma, Gland Pharma, Stelis Biopharma, and Vichrow Biotech for the production of vaccine doses.

With a production capacity of 850 million doses in the country, Sputnik V will provide a major shot in the arm in the fight against COVID-19. Having a third vaccine for public use in the country could mean bolstering the vaccination drive and reducing the strain on the production of the two vaccines that are currently in use.

How Does Sputnik Compare to Covishield and Covaxin?

Sputnik V is based on the human adenoviral vector platform.

The Oxford-AstraZeneca vaccine, being manufactured by Serum Institute of India (SII) here as ‘Covishield’, is also a viral vector vaccine.

In comparison, Bharat Biotech's Covaxin (BBV152) is an inactivated COVID-19 vaccine.

All of them require two doses, except Sputnik Light.

While Sputnik’s efficacy is 91.6 percent, Covishield is 62-90 percent while the clinical efficacy of Covaxin was found to have an efficacy of 81 percent in its Phase III clinical trial. Meanwhile, Sputnik V Light’s efficacy is 79.4 percent, said RDIF.

(This story was first published in FIT and has been republished with permission.)

(At The Quint, we are answerable only to our audience. Play an active role in shaping our journalism by becoming a member. Because the truth is worth it.)

Speaking truth to power requires allies like you.
Become a Quint Insider

or more


3 months
12 months
12 months
Check Insider Benefits
Stay Updated

Subscribe To Our Daily Newsletter And Get News Delivered Straight To Your Inbox.

Join over 120,000 subscribers!