The World Health Organization has granted Bharat Biotech's Covaxin Emergency Use Listing (EUL) for 18 years and above, according to reports.

India's homegrown COVID-19 vaccine has been dogged by controversy and manufacturing issues, dragging down the country's vaccination drive and putting global vaccine supplies at risk.

The indigenous vaccine, manufactured by Hyderabad-based Bharat Biotech was expected to play a major role in India's battle against coronavirus. However, nine months since the vaccination drive began, it has fallen short of its target time after time.

Here's a look at Covaxin's manufacturing and supply issues and its potential to contribute to India's vaccination programme.

Covaxin accounts for just about 11 percent of the total number of vaccine doses administered in India up to September. Covishield, manufactured by Serum Institute of India, makes up the bulk of doses.

This is even after the Centre consistently providing the company with ample support and endorsement.

Bharat Biotech initially produced 90 lakh doses a month. This was then augmented to 2 crore doses by May, the Union Health Ministry had informed the Supreme Court in an affidavit in May.

The Centre had projected that 55 crore doses of Covaxin, or an average of 10 crore doses a month, would be available from August to December. This was later brought down to 8 crore doses, a month later. Finally, the Centre said it expected only 3 crore doses in August. But even this was not met.

On 20 July, the health ministry first said that Bharat Biotech is producing 1 crore doses a month, and it will be ramped up to 10 crore in the coming months.

In the next question, the health ministry stated that the current average monthly capacity of production of Covaxin is 2.5 crore doses and plans to increase to 5.8 crore doses per month.

In the third question, the health ministry said Bharat Biotech was producing about 1.75 crore doses a month.

From January 16 to August 5, 6.82 crore doses of Covaxin were supplied by Bharat Biotech, the health ministry further said.

In January this year, its managing director Krishna Ella said that the company would produce 70 crore doses in 2021 through multiple facilities. This comes down to over 6 crore doses a month, on an average. But, at the time, the company was capable of producing just about 50 lakh doses a month, according to The Wire.

Bharat Biotech has five production units at Hyderabad, Bengaluru, Pune, Malur and Ankelshwar.

While the company has high hopes of augmenting its capacity at all these sites, there is lack of clarity about its plan and the progress.

Meanwhile, the Centre also announced its plans to upgrade three public sector plants – Haffkine Biopharmaceutical Corporation, Ltd, Bharat Immunologicals and Biologicals Ltd, and Indian Immunologicals, Ltd, – to manufacture 4 to 5 crore doses per month, under its ‘Covid Suraksha’ mission. However, none of these plants are operation as of now,..

He said that they are working with other companies and they should be able to reach the "10 crore figure by year-end.”

There have been controversies on the quality front, too. Bharat Biotech has not been transparent about the disclosure of Covaxin’s trial data.

In August, as the country was struggling to ramp up production of vaccine shots, Covid-19 task force member NK Arora said that the supply of Bharat Biotech’s Covaxin slowed down because the first few batches of the vaccine produced at the company’s new facility did not meet quality expectations, NDTV reported.

The chairperson of the Working Group of the National Technical Advisory Group on Immunisation, clarified that the batches that did not meet the quality standards were not released to the public.

• Tech challenge

• Human resources issue

• Long production cycle

• Shortage of key chemical

• Too many production units

Covaxin is an inactivated vaccine, developed using the Whole-Viron Inactivated Vero Cell-derived platform technology.

"Inactivated vaccines are one of the toughest to produce in the world,” Ella said.

Training people to handle live viruses is also a challenge, that would require at least six months.

Bharat Biotech has said that the production cycle is also long, which takes 120 days from manufacturing to release.

The sourcing of adjuvant from the US to boost the immune response has also been a task for the company, according to Business Standard.

Bharat Biotech has its production at too many units which are based far off from the company’s headquarters in Hyderabad, which is also a disadvantage, CNN reported quoting industry experts.

The Centre said repeatedly said it plans to vaccinate the entire adult population by the end of 2021. It now has less than three months to achieve its target.

While this is less than half the doses given on Prime Minister Narendra Modi’s birthday, it is still much higher than what we are achieving now every day.

India also needs to keep in mind its global commitments that might make the target even tougher to achieve. If the exports begin before December, we might have to produce more than estimated number of doses by 2021.

This is where the production of Covaxin will be a key constraint – both from Bharat Biotech and from the three public sector units.

(With inputs from The Wire, NDTV, CNN & Business Standard.)