Review panel asks vaccine makers to submit more data to get authorisation

Experts ask Bharat Biotech for phase 3 data, Serum's UK approval status

The wait for the Covid-19 vaccine just got a bit longer for India as two key players were told on Wednesday that their clinical trial data was inadequate for a fast-track approval. At a virtual review meeting, spread through the day, the subject expert committee (SEC) asked vaccine makers Bharat Biotech International (BBIL) and Serum Institute of India (SII) to come back with more data for getting an accelerated marketing authorisation.      

The expert committee, which is advising the Drug Controller General of India (DCGI) on the matter, flagged several concerns such as why the AstraZeneca vaccine, with which Serum Institute has a tie-up, has not yet been approved in its home country UK. The panel, comprising specialists in diverse medical fields, also sought details of causal relationship analysis of the serious adverse event of the Chennai participant in the Serum trial. Bharat Biotech, which was equipped with only phase 1 and 2 data, were asked to get back once they had sufficient efficacy data from phase 3 trial. 

Experts have pointed out that Serum did not have complete immunogencity data from the phase 3 trial on 1,600 persons. Immunogencity data refers to a vaccine inducing an immune response or producing antibodies in the subject. “SII finished their phase 3 trials on November 25, and the immunogenicity data or neutralising antibody titer is checked 15-days after the full immunisation  (two doses) is done on subjects. Therefore, it does not yet have the complete set of data for all 1,600 participants,” said an official in the know. 

Prime Minister Narendra Modi, who visited three vaccine manufacturing facilities in India recently, had said India would see a rollout soon.

Facing tough test

• Serum Institute asked to submit details about serious adverse event in the case of Chennai participant
• SII was asked why UK regulator was yet to clear Covishield
• Bharat Biotech told to submit data from phase 3 trials
• Pfizer representatives did not come for review on Wednesday
• Experts concerned about reports of Bell's Palsy in Pfizer-BioNTech trial subjects
• They would ideally want data on 2,000 Indian people from Pfizer 

The decision of the expert committee would be considered final as the DCGI is unlikely to take a contrarian call, according to sources.

Pfizer did not come for the review meeting on Wednesday, but it is expected to attend soon. So far, Pfizer, Serum Institute (SII) and Bharat Biotech have applied for an accelerated approval of their vaccines.  

The serious adverse event on the 40-year old trial subject in Chennai has been a controversial matter. “We asked the company why a vaccine developed by University of Oxford and AstraZeneca has not yet got the nod from their home regulator while a US vaccine had got it. We would like to wait until UK clears Covishield and would review those documents," said a source.

In case of Pfizer-BioNTech, experts are concerned about the reports of Bell's Palsy (temporary facial paralysis) reported in four volunteers. "USFDA is reviewing Pfizer's application and we would like to see what they think. Moreover, having data from Indians is extremely necessary. We are looking for data on around 2,000 Indians or so," said an expert.

Bharat Biotech, which is in the midst of a phase 3 clinical trial with 26,000 subjects, has not yet submitted data from this to the regulator for a review.