It's fair to say former Kent schoolboy Adar Poonawalla has come a long way since his days enjoying nights out in Canterbury as a teenager.

Now, the 40-year-old billionaire leads the largest production facility of Covid vaccines in the world and helps fund new schools and clean water plants in his home city in India.

GQ Magazine has named him one of the 50 most influential young Indians and his charitable efforts have earned him the accolade of Philanthropist of the Year.

It's a far cry from his school days as a boarder at St Edmund's in Canterbury, which he credits for "making me the man I am".

And it's that man who is now chief executive of the Serum Institute of India, which is making 70 million doses of the Covid vaccine a month.

The company, founded by his father Cyrus, currently has the Oxford/AstraZeneca vaccine rolling off its production lines and has signed contracts with three other developers - Novavax, Codagenix and SpyBiotech.

Before the pandemic hit, it was already the biggest vaccine manufacturer by volume in the world, making 1.5 billion doses annually to fight diseases like polio, tetanus, diphtheria and hepatitis B at its 100-acre facility in Pune, near Mumbai.

About two-thirds of all the children on the planet have been vaccinated with one or more of its products.

But Adar says his company had to quickly shift focus and divert resources to manufacturing Covid vaccines to help fight the pandemic.

He gambled on building extra capacity in the business ahead of time before the vaccines were approved for use. But it meant the company was best-placed to quickly meet the demand when many much bigger companies were not.

But the process came with huge levels of pressure, he says.

"Last year I was losing hair and under so much stress because if it didn't all work out, it would not only be a huge financial loss, but the world would not have a vaccine that we can produce at an affordable price," he said.

Now the company, which Adar runs with his executive director wife, Natatsha, is supplying Covid-19 vaccines to more than 60 countries, with more nations signing up every week.

While high-flying Adar continues to negotiate multi-million pound contracts to supply the vaccines to an increasing number of countries, he still has fond memories of his school days at St Edmund's, where he was a boarder.

"The experience I had there, I think made me the man I am today, " he said.

"The boarding school environment makes you tough and helps you deal with people from all different cultures and backgrounds.

"But the grounding and discipline, together with the sports and activities, were good and I have very fond memories of my friendships and going out in the city with schoolmates at the weekends.

"Our favourite haunt used to be Alberry's wine bar in St Margaret's Street."

Now a dad-of-two, Adar says he would welcome an invitation to visit his old school if the opportunity arose and would like to make a contribution, adding: "It's always good to give back to the institutions that helped make you."

Headmaster Edward G O’Connor said: "St Edmund’s School is immensely proud of the extraordinary work being undertaken by Adar to tackle the global Covid-19 pandemic.

"His visionary leadership on this critical issue provides a great example to young people of the transformative power of socially responsible business practice."

Adar studied maths, business studies and science at A-level - the latter his favourite because he always intended to join the family business.

He went on to study business administration at university and says that proved vital in his career.

"Science and business go hand-in-hand in what we do because of the deal-making I'm doing with various governments, " he said.

Adar is now listed as one of the 50 most influential young Indians by GQ Magazine and has been awarded an honorary doctorate of science from Oxford University.

The success of his business has afforded the family a glamorous, billionaire lifestyle but also a passion for the welfare of the people of their home city.

Adar was named Philanthropist of the Year in 2016 following his creation of the Villoo Poonawalla Foundation in memory of his late mother, which funds six schools, a hospital, and 25 clean water plants at different locations.

It also supports the operation of 250 trucks and machinery, picking up and processing waste in and around the city of Pune.

But his growing vaccine manufacturing plant keeps him extraordinarily busy, although with a huge sense of achievement.

"We never imagined the whole world being so dependent on us," he said.

"It's incredibly satisfying to know we are helping to save so many lives."

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