Viagra: an overnight success

World-leading chemist Andy Bell on co-inventing one of the biggest selling drugs in the world

In the canteen of Derwent College – possibly the greyest of the University of York’s original complexes – I meet world-leading chemist Andy Bell. The place hasn’t changed all that much since Bell first arrived here as a Chemistry student back in ’79.  It was a sunny day, he recalls, when he first toured the campus and decided then that it seemed like an interesting place to study. He was a straight-A pupil at school, though Oxbridge was off the cards because his physics wasn’t up to it – and there was “no way” he was going to Hull.

Bell studied hard with encouragement from his parents who themselves never enjoyed the benefits of higher education. “Anybody who hasn’t been to university can see that there’s a use for chemistry,” he enthuses. The hard graft soon paid off, and after graduation Bell began work at Pfizer where he would go on to co-invent one of the largest selling drugs in the world, sildenafil, better known by its brand name Viagra.


The 1992 discovery of Viagra was, like many an historic science innovation, a happy accident. Bell and his team of researchers had originally set out to develop a treatment for angina. The drug had proved disappointingly ineffective during trials and Pfizer was close to abandoning further tests.

The only notable response in their male trial subjects was a surprising side-effect overnight: an abundance of erections. It transpired that Andy and the team had stumbled upon a revolutionary treatment for erectile dysfunction. Viagra was soon developed and put on the market in 1998.

Before its launch, the only option for sufferers of erectile dysfunction had been a needle injection immediately before sex, or a prosthetic implant – neither of which were particularly appealing to patients. The little blue pill would improve millions of lives across the world. It would, moreover, make around $2 billion annually, not including illegitimate sales. “At the time there were a whole string of treatments coming on to the market which were clearly trying to build on the name – like ‘Viagrene’ and ‘Niagra’. Pfizer spent a lot of time trying to get those removed.”

It was with the large-scale success of the drug that Bell would require some media training. “It was obvious from the start that there was going to be enormous media interest,” he says. “It’s just human nature, there’s no getting away from it.”

He speaks with the weariness of an unheeded expert. From the outset, a giddy cultural fascination – and confusion – has surrounded Viagra and its effects, and the media was a source of both. “I could show you plenty of press cuttings. There were weird, crazy stories which scientifically made no sense. There was one headline from the Scottish Herald that read, ‘DRUGS TREAT BREWER’S DROOP’.

“The story went that Pfizer had been running clinical trials and that it would enable ‘bevvy merchants’, as they put it, to drink half a gallon of beer and still perform…”

Contrary to popular belief, the little blue pill does not increase sex drive; neither is it addictive, and nor will it cause boyfriends to cheat on their partners. The actual effect of Viagra is simply to trigger the dilation of blood vessels and ease blood flow. Besides sex, sildenafil has found numerous applications elsewhere: from aiding climbers with respiration at high altitudes to oxygen-starved babies in the womb. Bell also worked on another brand of the drug, Revatio, which is used to treat pulmonary hypertension and improve exercise capacity.

While at Pfizer Andy moved from “lifestyle” drugs to life-saving ones: he contributed to the development of voriconazole (branded as Vfend), an antifungal medication used to treat invasive fungal infections. Vfend made $676 million last year.

The margins made from life-saving drugs may be impressive, but their cost to patients is meanwhile a matter of life and death. “The concern I have is just the rising cost of treatments,” says Bell. “Historically the cost has related to materials and the complexity of the manufacturing process. But that seems to be lost because new treatments are coming forward which are small molecules that aren’t that expensive to make, but the price of those drugs is now based on how much the last one made.

“My impression over the last few years is that there’s more controversy nowadays over drug prices – some are extraordinarily expensive.” The high-profile case of US drug entrepreneur Martin Shkreli comes to mind, who infamously hiked the price of Daraprim, a drug used to treat AIDS patients, by over 5000 per cent overnight. 

There is no simple way to solve the problem of profiteering, but university research may have a role to play in finding new and alternative treatments to life-threatening diseases. Since leaving Pfizer in 2011 after 30 years at the company, Bell has himself worked at Imperial College, London, where he led  a project to discover inhibitors of the enzyme N-myristoyltransferase for the treatment of parasitic infections.

Pfizer has since opted out of “early discovery” research in the hope that biomedical centres in universities provide those innovations instead. When an effective treatment is discovered, the one-drug company is bought up at this advanced stage allowing big pharma companies to enjoy greater returns from their products. Universities hope to benefit from re-investing their slice of the profits into research facilities.

Having “gone all around the houses” of the pharmaceutical industry over the years, Bell’s next project in the pipeline is the launch of his own spin-out company. “I’m working on a new treatment for the common cold,” he says. “Potentially, it’s a big deal.”