Researchers around the world have worked together in an unprecedented fashion to develop vaccines and find potential cures for Covid quickly. A few vaccines have been approved in some countries for emergency use and many other promising candidates are in the pipeline.
The process of developing, testing and approving a vaccine or drug normally takes anywhere between four to 10 years. The search for a solution to the pandemic has compressed this timeline dramatically.
In India, three vaccine manufacturers—Pfizer, Serum Institute (for the Oxford/AstraZeneca vaccine) and Bharat Biotech (for a vaccine it has developed indigenously with ICMR)—have applied to the Drugs Controller General of India (DCGI) for emergency use approval so far. Of these, the Pfizer-BioNTech vaccine has already been approved for emergency use in the US, UK and Canada. The Oxford-AstraZeneca vaccine hopes to get approval from the UK drug regulatory authority soon.
While it may look as if the most difficult hurdle—the development of an effective vaccine—is now over, the road ahead is equally challenging. The Indian government and the DCGI will have to deal with three complex tasks where a single misstep could cost thousands of lives.
The vaccine approval:
As mentioned, three vaccine makers have sought emergency use approval from DCGI and one of them, Pfizer, has already secured similar approvals from several countries with very stringent regulators.While this is encouraging, an emergency use approval means exactly that—a drug/vaccine that has been approved for emergencies but not cleared as a standard treatment.
There is a reason why drugs and vaccines take so long to get approval. Rigorous clinical trials with large groups are conducted over years to test for efficacy and safety. While all the drugs applying for approval with DCGI have conducted/are conducting phase three trials, there is a lot that we do not know yet.
For example, why a few people administered with the Pfizer vaccine get serious side effects—including an anaphylactic shock—is still not clear. Nor is it certain how long the vaccine protection lasts. Most regulators therefore have approved these for emergency use while also mandating post-approval trials and monitoring.
Pfizer has committed to post-approval studies in other countries. These include additional randomised clinical trials, special population studies, and further safety and efficacy testing. If all goes well, it may get approval as a standard vaccine two or three years down the line.
The DCGI needs to make its own decisions. A 2019 regulation allows it to give accelerated approval on the basis of little initial data. But given the high stakes, it needs to give these clearances after demanding post-approval trials and monitoring.
The question is, will it do so transparently and on the basis of proper data? Earlier, the DCGI has drawn flak for approving Biocon’s itolizumab and Glenmark Pharmaceuticals’s favipiravir for emergency use in Covid cases without seeking enough data. But these drugs were meant for only a small subsection of patients and at the discretion of the physician. The risks in the vaccine approval are far higher given that almost the entire population will get it eventually.
The vaccination programme:
The government has announced it will use the election machinery and the existing cold chain to roll it out. It will administer 60 crore vaccine doses within six to eight months to 2 crore frontline workers, 1 crore healthcare workers and 27 crore people who fall in the prioritised age group that is over 50 years of age, along with those under 50 but with comorbidities.
This is a complex task. The existing cold chain is unevenly distributed. Some states have adequate facilities while others—such as UP, Bihar and Jharkhand—do not have anywhere near enough. Even after enlisting the private sector, the target is ambitious. Each person needs two doses of vaccine at a fixed interval for any degree of protection. In trials, the vaccine has been shown to protect 95% of the volunteers if the doses were administered properly.
Whether that will hold true in field conditions is unclear. Moreover, the period for which a person will be protected after two doses is not known. Will they need booster shots in three months or six months? Finally, ensuring that a person does not suffer from allergies and will not show adverse effects immediately after vaccination in field conditions adds to the problems. Frontline workers (2 crore) and healthcare workers (1 crore) may be easy to vaccinate. But it is the other 27 crore spread far and wide that will prove a challenge.
Post-vaccination monitoring:
There are still too many things not known. When the booster shot will be necessary is not clear. Some side effects and/or drug interactions may show up after some time. Precautions for non-vaccinated people living with vaccinated ones also need to be communicated. Monitoring crores of vaccinated people is not easy. Moreover, monitoring protocols are important. Will these be through self-reporting on a digital app or done in a healthcare setting where the person checks in periodically? Given that vaccination of the 50-plus age group is a priority, these are important questions.
One big hurdle has been crossed. But the war is far from over.
(prosaicview@gmail.com)
Prosenjit Datta
Senior business journalist