New drugs for old bugs

Finding new antibiotics has become one of the most urgent priorities for scientists around the world.  We have become so used to the life saving properties of drugs like penicillin or streptomycin that the idea that the era of effective treatment of infections might be coming to an end sounds like science fiction.

But it is not fiction: for the last few years, scientists and even some politicians have been sounding alarm bells – if we don’t do something pretty quickly, then the unthinkable could happen – we will be facing life-threatening infections without the means of treating them.
How has this come about? Almost as soon as antibiotics were invented, back in the 1930s and 1940s, it became clear that bacteria could develop resistance to them. Bacteria were able to change their genetic make up so that the antibiotics were no longer effective, and the treatment failed.

To keep up with the bacteria, scientists in universities and drug companies around the world worked hard to come up with a steady stream of new antibiotics that would get round the road blocks that the bacteria had put up.

It was a cat-and-mouse game: doctors would use a new antibiotic that was effective, so the bacteria developed a way of blocking it and the scientists had to go away and develop another new antibiotic that was even stronger than the previous one. The scientists were on top again – but often, not for long, and cycle repeated itself.

And so it went on – until the last decades of the previous century, when the pipeline of new antibiotics started to dry up, and slowly, inexorably, the bacteria started to get the upper hand. From all around the world doctors started to report cases of infection with bacteria that were very hard to treat with the antibiotics we had available, and in a few cases, completely resistant to all antibiotics.

What are we doing about it? Of course the simple answer is – discover new antibiotics, even better than the existing ones and strong enough to kill even the very resistant bacteria. And there is much effort going in to do just that. We also need to use the antibiotics we do have, much more carefully – so called antibiotic stewardship.

This is a lot about education – partly of doctors in how they prescribe antibiotics, but also of the general public who must understand that using antibiotics needlessly – for instance for viral infections that will not be cured by antibiotics – just wastes a valuable resource and drives up the problem with resistance. And very simple things, such as encouraging hand washing to limit the spread of bacteria, are all part of the solution.

So why don’t we just discover new drugs? In part this is because it is hard – the bacteria are very smart, and finding ways to get round their defences is difficult. But there is another, quite different and rather unexpected problem and for that we need to turn for help not to scientists but to economists.

Discovering new drug

Discovering a new drug – any kind of drug – and then developing and testing it so that it can be safely used in patients is a long, and very expensive process.

Multinational pharmaceutical companies invest huge amounts of money – typically, hundreds of millions of dollars – in research and development in the hope that of the many chemicals that they first identify in the laboratory, at least one will turn out to be both effective and safe. They then hope to recoup some of the cost, and of course produce a profit for their shareholders, when they finally get to sell the drug they have developed.

And here’s the problem. Any new antibiotic that was so effective that it could treat the multi-resistant bacteria would be such a valuable resource that doctors would, naturally enough, not want to “waste” it when a simpler antibiotic would do the job.

Doctors will say to the drug company, thanks very much for discovering this new drug but now we are going to put in a cupboard under lock and key and only use it when we are really in trouble. That’s great for patients but very bad news for the drug company, who wont get to sell much of their drug and so wont recoup any of their investment.

So is it stalemate? Thankfully, scientists, governments and the drug companies themselves recognise this dilemma and are working hard to try and find ways round it. It seems likely that we are going to need to find new and novel ways of funding drug discovery that will both incentivise the pharmaceutical industry and also ensure that there is a steady supply of new, potent antibiotics for patients.

This is a real global problem, one that the World Health Organisation recognises as needing a global strategy to combat. We may have thought that infectious diseases was a problem of the past  - but it is not going away yet, and we ignore it at our peril.

(The writer is President, International Society for Infectious Diseases)