The TLDR: The hasty approval of the vaccine raised a firestorm of criticism. In turn, the critics themselves were attacked. On the sidelines, makers of the two approved vaccines—Bharat Biotech and Serum Institute—got into a slanging match. After the dust settled, we now know more but are even less reassured. 

A quick recap: Last week, the government approved two vaccines: Serum’s version of the Oxford vaccine (Covishield) and Bharat Biotech’s Covaxin. But it became quickly clear that they were given the go-ahead without proper trial data (Our Monday explainer has all the details). 

Do we know more about the data?

Yes. It has been now confirmed that for Covaxin, we have zero efficacy data—whether a vaccine is effective in protecting the body against infection. It was approved solely on the basis of Stage 1 and Stage 2 trials which only establish that the vaccine is safe, and that it stimulates the production of antibodies, T cells etc.—i.e. its immunogenicity.

For Covishield, we only have AstraZeneca’s efficacy data from Stage 3 trials in the UK and Brazil. In India, Serum Institute has only conducted a safety trial with its version of the Oxford vaccine on 1,200 volunteers. And it has submitted immunogenicity data on less than the required 400 participants. 

Do we know which one is safer?

Safety is established in Stage 2 trials. We have far more India-specific data for Covaxin—which has been published in established journals. But we can also assume that Serum’s version of the Oxford vaccine will be just as safe. In fact, when taking a crack at Covaxin, Serum CEO Adar Poonawala told NDTV:

“There are only three vaccines in the world who have proven efficacy... it's Pfizer, Moderna and Oxford-AstraZeneca, these are the only three vaccines which have been proven to work. Everything else has been proven to be safe, just like water. But the efficacy to know how well a vaccine works, 70%, 90%, 80%, has only been proven in these three vaccines.”

So no one is disputing Covaxin’s safety, not even Serum. 

Point to note: As per the government guidelines, both Bharat Biotech and the Serum Institute of India (SII) have to submit reports on “adverse events”—i.e. serious side-effects—every 15 days for the first two months. After which, they can do so once a month.

So how will we know if Covaxin works?

One answer: Bharat Biotech’s stage 3 trials to determine efficacy are underway, but those results won’t be available until March. The original launch date announced last year was around April. 

The company’s answer: The company’s Managing Director Krishna Ella held a lengthy press conference where he essentially laid out three arguments in favour of Covaxin:

One: the vaccine uses an entire inactivated vaccine—unlike others which use part of the virus’ genetic material that targets its spike protein. It will therefore be more effective if the virus evolves a great number of mutations in its spike protein—as is the case with the latest strains. Ella admitted this is a “hypothesis” and asked for a week to come back with data.

Two: Covaxin uses a proven method of vaccine delivery—using cells from the kidneys of African green monkeys—which has a long-established safety record. Ella said:

“If yours is a proven platform technology, safe platform technology, and good pre-clinical trial data is available, then you can get [an] emergency license for the product.”

Three: Stage 2 trial data has already revealed “remarkable efficacy,” and existing guidelines permit approval in such cases when there is an emergency. 

Point to note: The company also revealed its plans to test the vaccine on children between the ages of 2 and 15. Covaxin is already the first Covid vaccine to be administered to kids above the age of 12.

The unexplained wrinkle: Unlike Covishield, Covaxin will also be administered in “clinical trial mode”—outside of the company’s Stage 3 trials—which introduces all sorts of complications.

Do we know what that means?

Nope. All ‘clarifications’ have just muddied the waters further.

• According to Ella, there will be no placebo group unlike a clinical trial—and therefore no double blind testing which is required to determine efficacy. 
• The Health Minister, OTOH, claims: “All Covaxin recipients to be tracked, monitored as if they're in trial."
• So will these people be treated as trial participants, but not subject to trial protocols? And as Quartz points out: “[G]iven that all vaccine recipients must register with the government, it’s unclear how tracking for Covaxin will differ or be more robust than that for the Covishield vaccine.
• The reality is that no one knows how this will work—including Ella who said the company is “still trying to figure out various modalities” of the difference between vaccinations within and outside clinical trials. 
• Point to note: There are key distinctions in the area of consent. Volunteers willingly agree to become guinea pigs. Someone given a vaccine in a mass government-driven campaign does not.

Adding to the confusion: AIIMS chief Randeep Guleria who said Covaxin will only be “a backup for emergency use in case of reinfection”—which was furiously refuted by Ella. In other words, even government experts are not clear how and when Covaxin will be administered.

The bottomline: Mass vaccination campaigns require public trust. The approval—given in haste and without any planning—has created a PR nightmare for both Bharat Biotech and the government. And that’s bad news for everyone, even more so if Covaxin does indeed turn out to be a very good vaccine.

Reading list

Mint has the best summary of the Bharat Biotech defence. The Telegraph reports on the Serum vs BB jhagda. The Wire lists ten unanswered questions about the Covaxin approval. A must read: Dr Gagandeep Kang’s Times of India interview on the vaccine approvals. This older Reuters piece on Sputnik V reminds us that untested vaccines create the risk of further uncontrolled mutations. We did a detailed explainer on the controversy over both vaccine approvals—which includes an extensive reading list, as well.