Gennova Biopharmaceuticals granted conditional permission for human clinical trial of its COVID-19 vaccine

NEW DELHI: Human trials of the first indigenous mRNA Covid vaccine candidate have been permitted by the Drugs Controller General of India (DCGI) while the initial results are likely by March next year. 

It assumes significance as covid vaccines based on this platform, such as those by Pfizer-BioNtech and Moderna, currently appear out of bound for India.

The  Central Drugs Standard Control Organisation’s Subject Expert Committee on Wednesday granted conditional permission for phases 1, 2 human clinical trial of the vaccine candidate developed by the Pune-based Gennova Biopharmaceuticals Ltd in collaboration with HDT, the US. The recommendations of the panel were later approved by the DCGI. 

“After detailed deliberation, the committee recommended for grant of permission to conduct phase 1 and 2 clinical trial subject to the condition that the interim results of phase 1 study shall be submitted before proceeding to the next phase,” the panel said. Experts pointed out that the success of some mRNA vaccines has come as a surprise.

Instead of exposing defences to a protein directly, the antigen is delivered indirectly through a circuitous route.

“mRNA molecules takes genetic instructions for producing a spike protein and, once inside a cell, that spike gene is read by cellular machinery to make spike proteins,” said a virologist.

He said the body receives a target antigen — the coronavirus spike protein — despite the fact that an mRNA vaccine doesn’t itself contain the antigen.

Two explanations have been offered for this.

“One possibility is that having a cell read the spike gene to make a protein — instead of delivering the fully-formed spike protein — more closely mimics what happens when SARS CoV 2 replicates during infection.” Pfizer, for example, had developed two drug candidates.

While one only included instructions for producing the spike’s tip, another one which showed 95% efficacy produced a full-length protein.

“It suggests that the immune system responds better when exposed to the entire spike protein,” he said, adding that another explanation is that additional modifications to the mRNA molecules may be influencing effectiveness.