Expert flags Covishield’s neuro-inflammatory risk, efficacy against new strains

BENGALURU: On the eve of the launch of Covishield, the Oxford-AstraZeneca-Serum Institute of India (SII) vaccine for Covid-19 in the country, medical experts have drawn attention to some unanswered questions in a public assessment report.

These pertain to the control of the transmission of SARS-CoV-2, its efficacy against the new strains of N501Y & B1.1.7 or other such mutations in the spike protein of the SARS-CoV-2 virus and the reported adverse events (of the vaccine).

“The reported adverse events of the vaccine suggest that there is a high risk of neuro-inflammatory disorders, including transverse myelitis, facial nerve palsies and trigeminal neuralgia that need to be closely monitored,” Dr Vishal Rao, well-known oncologist and member of an expert committee of the Covid Task Force, Government of Karnataka, has pointed out in a scientific correspondence, which was shared with The News Indian Express.

Experts have also raised concerns about some other open issues regarding the vaccine, such as the duration of protection from antibody response and dosing beyond the two-dose schedule, effectiveness of the vaccine against long-term effects of Covid-19 disease, effectiveness in children below 18 years of age, pregnant, lactating women and immune-compromised individuals.

While commending the transparency, good clinical and ethical practices of the vaccine in ‘The Public Assessment Report of the Authorisation for Temporary Supply of AZD1222 from the MHRA, Government of UK,’ Dr Rao has stated that the data presented in this report has some “unanswered questions pertaining to the control of the transmission of SARS-CoV-2 or to prevent infection, though it seems to reduce the intensity of the illness. We will have to continue to wear face masks even after getting vaccinated,” he has stated.

The Public Assessment Report has highlighted Adverse Events (AEs), Serious Adverse Events (SAEs) and the risks that ought to be included in the information for healthcare professionals and recipients of the AstraZeneca/Serum Institute of India Covid-19 vaccine ‘Covishield.’

Adverse events need to be monitored, says doctor

"According to the report, ‘Covishield’ uses the recombinant (synthetic) particles, which target a particular region of the virus — Spike (S) glycoprotein. The question remains whether this vaccine will be effective against the new strains of N501Y & B1.1.7 or other such mutations in the spike protein of SARS-CoV-2," Dr Vishal Rao has asked.

He has also pointed out an impor tant aspect of the study-based report, which was the “use of paracetamol, which has the potential to confound the symptoms developed by volunteers in groups. There is limited information available on its efficacy on participants aged 65 years or above,” he pointed out.

In his correspondence, Dr Rao has also mentioned about the reported adverse events (of the vaccine) which suggested that there is a “high risk of neuro-inflammatory disorders, including transverse myelitis, facial nerve palsies and trigeminal neuralgia that need to be closely monitored.

There was one serious adverse event (SAE) reported in the lay press from the India study too, but there is no information in the public domain on the causal relationship of this complication,” he has stated. In the case of the mentioned SAE, the SII had earlier said that the

“Covishield vaccine is safe and immunogenic…and that all the requisite regulatory and ethical processes and guidelines were followed diligently and strictly.”

Dr Rao and other experts, noted that “similar levels of transparency are commendable and need to be adopted by all other Covid-19 vaccine candidates. This will help volunteers and participants receiving the vaccine make a more informed decision,” he said.