Vaccine safety is always a matter of risks and benefits, but tech advances help reduce the risk: Experts

January 5, 2021 0 By FM

Even though safety is paramount when it comes to vaccines, it is the risk-benefit ratio that prevails in the end, emphasized experts at a webinar organised by Future Medicine on COVID Vaccination: Scientific Position, Clinical Evaluation & Implementation. Despite being developed in less than a year, they pointed out, COVID-19 vaccines have elicited a high degree of confidence from the scientific as well as clinical community.

Dr Suresh S Jadhav, the head of vaccine R&D at Serum Institute of India reassured the audience that his company was not taking any chances when it comes to safety.

The vaccine is basically a foreign protein and so there will be a reaction, he pointed out. However, SII has taken strict measures to ensure the first priority to safety standards of the vaccine, and these were strictly monitored throughout all the phases of the quality assurance, he added.

“We have made their [Oxford-AstraZeneca] vaccine candidate to pass through 9 months of phase-I, 7-8 months of phase-II and 6-7 months of phase-III. So, I can assure you that, on the safety side, there is absolutely no issue. Regarding the temperature required for safe-storage, we have taken enough quality assurance tests,” Jadhav said.

He said 50% of the vaccines manufactured by the company will be reserved for India, while the other 50% will be given to GAVI, the Vaccine Alliance and other agencies.

Dr Jadhav pointed out that the vaccine will deliver the required antigen in one dose, unlike others like the Russian vaccine that may require two subsequent doses.

“Presently, we are collaborating with AstraZeneca for making a billion doses. We have entered into an agreement with another foreign company to make another one million doses by the end of 2021,” he added.

In addition to the Oxford-AstraZeneca vaccine, branded ’CoviShield’ in India, Serum Institute is working on three other candidates, he informed.

One is an RBD-Fc-based COVID-19 Vaccine. RBD, or the receptor binding domain in the spike protein of the SARS-CoV-2 virus, is responsible for binding to the angiotensin-converting enzyme-2 (ACE-2) receptor. The vaccine has completed only the phase-I and phase-II trials and the company is now moving to phase-III trials  next month, he added.

“We have also transferred technology from a company in the US which uses a live-attenuated vaccine. We are also working over the re-purposing of the BCG vaccine we have, though its mechanism of action is still not clear. However, clinical trials have shown that among the whole number of patients which received the BCG vaccine, only 1.8% developed the symptoms of COVID-19. We are presently associating with ICMR for the experiments relating to this”, he said, participating in the webinar moderated by Dr Ravindra Mehta, MD, FCCP,
Senior Consultant and Chief Pulmonary, Critical Care and Interventional Pulmonology, Apollo Speciality Hospitals, Bangalore.

Dr Satish Chandran, CEO of Akshaya Bio Inc. and Somahlution Inc., said the benefit-to-risk ratio is higher in vaccines than therapeutics. “What we can expect is only a balance of the high degree of ‘benefit to risk’,” he noted.

He pointed out that the efficiency of the Pfizer–BioNTech vaccine was found to be 95%, but some of the recipients showed local reactions such as pain, swelling and erythema, and systemic reactions such as fever, headache and myalgias.

As far as a vaccine is concerned, he said, safety is the first hallmark, but ‘zero risk’ is only a theoretical concept.

“Of course, there may be some adverse reactions somewhere, in the case of COVID vaccines, but it may take another 12 months to know what will be the real effect of the vaccine,” he said.

Even though some of the vaccines under testing for COVID-19 may fail, Dr Satish Chandran said the process of developing the vaccines may turn to be a ‘great exercise and experiment’ which can help the development of other vaccines also for the future.

Dr Alok Roy, Chairman of Medica Group of Hospitals, Kolkata and Chair, FICCI Health Services Committee, said that the primary task at hand in India is to vaccinate the 10 million people most at risk, including 2-3 lakh frontline healthcare workers. After that, high risk groups such as those above 60-50 years will be vaccinated, he said.

He said the private sector is happy to provide infrastructural facilities, transportation, and on-the-spot training for professionals. “We are happy to work with the vaccination process’, he said, “as the beneficiaries are not the government, not the private, but citizens of the state”.