Covid-19 no longer public health emergency. But a new mRNA vaccine has been authorised for emergency use

On how to use the booster dose, a document on the website says, GEMCOVAC-OM should be administered in a single dose to individuals above 18 years of age, at least four months after completion of primary vaccination with either Covaxin or Covidshield.

A volume of 0.1 ml should be administered intradermally without a needle using a device called the Tropis, developed by PharmaJet, a company based in Colorado, US, it added. Further, it can be stored in regular refrigerators as it can be stable between 2 to 8 degree Celsius.  

According to details of the trial available online, in phase III, more subjects in the GEMCOVAC-OM group (252) achieved a two-fold rise in immunoglobulin G antibody titers as compared to subjects in the Covishield group (102) on Day 29. The immunogenicity cohort consisted of 271 participants from the GEMCOVCAC-OM arm and 133 from the Covidshield arm respectively.

The Phase III clinical trial was conducted with 3,140 participants who were randomised to receive either GEMCOVAC-OM or Covidshield in 20 centres across 13 cities.

The same Pune-based biotech firm had got an mRNA Covid-19 vaccine approved last year, but it failed to take off. 

Emergency usage now

In cases of declared health emergencies, despite a vaccine not being tested for its complete efficacy and safety, the regulator (DCGI) can approve its widespread use.

The fact that GEMCOVAC-OM was approved under the EUA after the World Health Organization Director-General, Dr Tedros Adhanom Ghebreyesus, announced on May 5 that the COVID-19 pandemic no longer constitutes a public health emergency of international concern has surprised many. 

Public interest lawyer and activist Prashant Bhushan said on Twitter, “Shocking that the Drug controller of India has approved an mRNA vaccine for omicron under emergency use authorisation.” 

Virologist and microbiologist at the Christian Medical College in Vellore, Gagandeep Kang told Down to Earth (DTE), “On the question of emergency use authorisation now, the government has to at some point say enough and start following the regular process. Though there are no concerns, if there is a process and the process must change, it should not be a reactive change of process.”

“Some of the flexibility that was brought in for covid vaccine approvals, like rolling reviews and seamless trials, are things we should incorporate in everything that is a solution to a public health crisis. That would be a good takeaway from the pandemic for drug approval processes,” Kang told DTE.

Kang said no vaccine is 100 per cent safe. However, she added, “There’s nothing that has shown common side effects. So I don’s think we should expect a risk profile than one that is higher than before”.

On why we need an Omicron-specific booster, Kang explained to DTE, “If we see a bivalent booster, then we see a very heavy weightage given towards the SARS-CoV-2 ancestors. If we want to overcome a bias that the immune system has then it is better to have a vaccine target its latest version of the circulating virus, which is the Omicron variant.”