There is not just one type of clinical trial. Expert Dr. Adam Kittai explains the types and how the trials are conducted, including randomized and double-blind studies.
Dr. Adam Kittai is a hematologist and an assistant professor at the The Ohio State University Comprehensive Cancer Center – The James. Learn more about Dr. Kittai, here.
Okay. You mentioned randomized clinical trials. There are a couple of other clinical trials as well. Would you define them and tell us how they’re different from one another?
Yeah. So, a randomized trial is when you enroll onto a study, and you get randomly assigned to either the experimental arm or the control arm. The experimental arm is that new drug that we talked about. And the control arm is usually the standard of care. So, that’s a randomized study.
And randomized studies are usually Phase III trials, but they can be phase two in some scenarios as well. You have – usually that’s paired with a randomized control study. So, a control study is just there’s a control arm, that’s what that means. But those usually go hand in hand. Those are usually together.
And then another trial is the double-blind clinical trial. So, a double-blind clinical trial means that once you’re randomized to either the experimental or the control, neither you nor the physician know what drug you’re taking. And that usually is not used in CLL trials. Usually, we know what drug the patient is assigned to. And the reason why that is, is because oftentimes we’re looking out for specific adverse events or toxicities of the drugs we’re implementing at Phase III.
And then, also, if you’re getting a triplet versus a doublet, meaning three drugs versus two drugs, it’s very hard to blind somebody to know which drug they’re on because obviously you’re getting three drugs versus two drugs. Or if an infusion is involved in one arm but not in the other arm, you obviously know that you’re getting an infusion versus an oral drug.
Ah, okay. Are there common clinical trial terms that you think patients should know about?
I think we covered most of them. So, knowing that phase one is typically the first in the sequence of events that I would ask your physician if this was a first in human study, right, because that comes with some special considerations knowing that you are the first human to receive a new drug is very important. Versus a phase three study where, you know, you know this drug has already gone through phase one and two in development, meaning it’s been given to a lot of patients, and they’re just looking to see if it’s better than standard of care. So, I think knowing those general concepts about what’s the difference between a phase one and a Phase III study, it’s very different. I think it’s important to keep those in mind when talking about clinical trials and discussing with your doctor.