New Delhi, Union Health Minister Harsh Vardhan clarified on Sunday that the government is yet to take a final decision on phase-3 trials of the Russian COVID-19 vaccine candidate Sputnik V.

"This issue is still under consideration and no final decision on Sputnik V vaccine developed by Russia has been taken as yet," he stated while addressing his social media audience during his weekly programme 'Sunday Samvaad'.

The clarification by the minister has come after a pharmaceutical giant, which partnered with Russia's sovereign wealth fund in September to conduct final trials and distribution of the Sputnik V, sought permission for the same from Drugs Controller General of India (DCGI) on Friday.

Hyderabad-based drugmaker Dr Reddy's Laboratories (DRL) had partnered the Russian Direct Investment Fund (RDIF) last month to conduct final-stage human trials and distribution of Russia's Sputnik V Covid-19 vaccine in India. Two days ago, the DRL had applied to the DCGI for permission to conduct the phase-3 human clinical trials of Sputnik. Upon regulatory approval in India, RDIF will supply Dr Reddy's 100 million doses of the vaccine, the firm had said last month.

The trials of Sputnik V are mired in controversy. The Russian government registered Sputnik V as a COVID-19 vaccine without conducting final clinical trials. Besides, the phase I and II of the trials involved merely 76 participants. The Indian scientists and medical experts are also of the opinion that the Indian government should conduct phase-2 trials of the vaccine to prove its safety and efficacy.

Russia, had announced in August that it has developed the world's first coronavirus vaccine. However, the country had made the announcement before completion of phase-3 trials. A vaccine is deemed safe to be commercially available only after a larger efficacy trial which involves thousands of participants in the phase-3.

However, the study of Sputnik trials published in The Lancet declared the vaccine as "Safe, well-tolerated, and does not cause serious adverse events in healthy adult volunteers."

As per the study, two small trials were conducted on two groups involving 38 healthy adults between the ages of 18 and 60, each. They were given a two-part immunisation. Each participant was given a dose of the first part of the vaccine, and then a booster with the second part, 21 days later. These volunteers were monitored over 42 days, and it was found that all of them developed antibodies against the virus within three weeks.

After widespread criticism of conducting relatively small and early trials before registering Sputnik V as a COVID-19 vaccine, Russia said that a more rigorous phase-3 clinical trial has been planned with the involvement of 40,000 volunteers "from different age and risk groups".