Prof. Alan Burnett from Cardiff University, Cardiff, UK describes the different phases of clinical trials and how they work. Recorded at the American Society of Hematology (ASH) Annual Meeting 2015, in Orlando, FL.
This programme has been supported by Pfizer, through an unrestricted educational grant to the Patient Empowerment Foundation.
View more programs featuring Alan K. Burnett, MD, FRCP
Become a member to access our latest content and be the first to know about new programs and information.
There are different types of trials. Some are where the drug, not a lot is known about the drug and how it works when it’s given to humans, and so the first stage in the development of a drug is to find out what dose is suitable. And so that’s done by taking groups of patients and gradually giving them an increasing dose of drug until they start seeing side effects, and then that defines the maximum dose that patients can be given. That’s a so-called phase 1 trial.
And then the next thing that people try to do is find out, and they may see some responses in a trial like that, but then they would take that dose they discovered and then look at more patients and see what proportion of patients got a response. And if that’s encouraging, they would say, well, we’ve got a drug here that’s really worth further development, and they would take that into what’s called a phase 3 trial, or a randomised trial anyway, where they compare it maybe with the standard care that’s already available, plus either the standard of care with this drug, or this drug on its own. And that’s the big phase 3 trials that take, you know, 3, 4, 5 years.
So it’s quite an expensive and quite a long procedure, and patients can back out of it at any time, they don’t, they’re not imprisoned in a trial just because they volunteer at the beginning. As I say, it’s pretty unusual for patients to be worse off being in a clinical trial, but they may, the drug may not work, and so they may not benefit. Everybody goes in optimistic but, you know, they don’t always work.