Clinical trials

March 2006

Taxi driver: How come they are allowed to give this untested stuff to human beings? Because if something goes wrong, people get seriously ill. I’d vote for anyone that bans that – its not what a civilised society should do.

Stephen: No matter what the substance – aspirin, antibiotics, lettuce – someone has to be the first person to put it in their mouths and swallow, and until they do, nobody actually knows for certain what will happen.

Taxi driver: But what about the scientists? They are supposed to be able to work these things out. They have obviously made a mistake if they didn’t see this side-effect coming.

Stephen: Scientists can attempt to make exact predictions about anything, but the more complicated the context of the prediction, the less accurate the result is likely to be. The phenomena which affect us (such as gravity, electricity, and so on) and the elements which make us, all existed before life did. But when evolution got started, the organisms using all these forces and elements became more and more complicated: now there may be millions of steps in a process, and millions of processes, and we will never know what all of them are exactly. The way all these things interact in our bodies is extremely subtle, and slightly different in each one of us, because we are all different after all. So if you measure the speed of light in 100 different places on the planet, the results are always exactly the same. On the other hand, when you apply the same stimulus to 100 people, the results are usually similar, but not identical.

So instead of making an exact calculation where we can say “This will definitely happen”, drug developers can only ever say “This will probably happen” – to a greater or lesser extent. Before any new drug is given to people to try, huge numbers of experiments are carried out to check everything that can be checked, and this builds confidence in the predicted effect on patients.

Taxi driver: I don’t understand why they can’t just do all of this in the lab. Then you could test it, and test it, and test it, millions of times on cells from all sorts of people.

Stephen: Well, are you exactly like all other taxi drivers? Do you all react in exactly the same way to everything, so that a scientist can predict what would happen? Would you be the first person to take a drug that had never been taken by a living person before? You’d be happy to do that, knowing that men in white coats can predict what happens in millions of glass jars?

Taxi driver: Oh, I see what you mean… no, probably not. It just doesn’t seem right, though, does it? I mean, that a clinical trial can go wrong like this.

Stephen: But the trial hasn’t gone wrong. Of course it feels like that to the subjects – the ones who took the experimental drug – but the trial is an experiment designed to find out if it does any harm before the rest of us take it. And now we know. In fact there are two stages: first healthy people take it to see if it does any harm; then, if it is safe for healthy people, it is given to sick people (the ones you hope it will help) knowing that there is little risk of it doing any damage. Then you can see if it has any benefits.

Taxi driver: So why not just give it to the sick people to start with? They might be grateful to take the risk.

Stephen: If you give it to sick people they are weak already, and if there were any side effects it might make them worse or kill them – that would be unethical.

Taxi driver: Ethical? Don’t talk to me about ethics! I mean, there are stories in the paper all the time about drugs with side effects that have to be withdrawn… People won’t stand for it and quite right too. We have to make a stand or nobody in those big drugs companies would do anything ethical. They’re just out to make money from our suffering.


We don’t have any really big diseases left here, anyway. Why aren’t they making cures for all the awful things that people get in Africa? It just seems a bit much that they are giving things to healthy people in rich western countries when they could be putting a lot more effort – maybe the UN could pay for this – curing all those diseases in Africa. That would be ethical.

Stephen: But what if I told you that drugs already exist that would cure a lot of those people in Africa at a stroke?

Taxi driver: I wouldn’t believe you.

Stephen: It could be true. Maybe they have come up with cures, but they are cures that have bad side-effects for some people. Maybe for every thousand it cures, it causes all kinds of extra trouble for one person. Drug authorities wouldn’t approve something like that: they’d get in all sorts of trouble. Imagine the headlines: “Regulator Approves Drug With Known Side Effect Horror”! Once some people suffer serious side-effects, it’s likely to get withdrawn, however effective it is for the vast majority.

Taxi driver: Are you saying the authorities are only interested if a drug company comes up with a cure that cures everybody? They’d rather many people die of the disease than one person dies of the cure? If one person has bad side effects, they’d allow millions to die?

Stephen: I’m sure it’s not what they want, but you can understand how they’d make that decision. You said it yourself two minutes ago – once the public finds out about the side-effects, they wouldn’t stand for it and rightly so.

So what do I owe you?

Taxi driver: Well now, Brick Lane to Oxford street, that’ll be £1,273.00… No, gov, only joking. Thought you might be one of those one-in-a-million guys…

Discussion points

Drug trials are there to help us balance the needs of a sick population for effective medicine against the human rights of an individual not so suffer harm. Where do you draw the line? If you had a treatment that killed one and cured two, you wouldn’t let it go ahead – but if you had a treatment that killed one and cured 100 million, what then?

Surgery always carries a greater risk than public opinion would be prepared to put up with from a drug treatment. Despite this, increasing numbers of people choose to undergo non-essential surgery, for example, to improve their appearance. Why do you think so many people find this risk acceptable, and the risk of side-effects from drugs not acceptable?

What do you think the pharmaceutical companies should do to minimise the risks to people who help them in drugs trials, and to patients?


Please contact us with any comments you may have on this debate.

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