Latest / EHA Unplugged / Innovative Trial Design (EHA2024)
Transcript
- 0:06In this episode of EHA Unplugged, we will revisit a
- 0:09spotlight talk from EHA 2024. Doctor Yurian Firstlaus from the
- 0:14Erasmus Medical Center in Rotterdam discusses the need to
- 0:17use innovative clinical trial designs in the era of
- 0:20personalized medicine in hematology.
- 0:22My name is Yurian Firstlaus. I'm a hematologist at the
- 0:25Erasmus MCA in Rotterdam and I'm also highly involved in trial
- 0:30design and within the whole form and.
- 0:33Related to this topic, do some research so for those of you who
- 0:38are. Aware of clinical trial design.
- 0:41There are a couple of stages to consider.
- 0:43In the clinical trial development and the 1st.
- 0:47Part of trial. Development.
- 0:48Is the idea. Everything starts with an idea
- 0:50and a drug and. Opportunity to investigate.
- 0:55An expert do an experiment and usually use a control and when
- 0:59there is a design you need to be.
- 1:01Aware of the effect size of your.
- 1:04Drug and discuss. That with your statistician.
- 1:07And as a result of that. There usually.
- 1:09Comes a protocol and. Eventually you'll start.
- 1:13Recruiting patients and when you recruit patients, there might be
- 1:18room for interim analysis. When you.
- 1:20Have the time and the equipment to do that and at the end you do
- 1:25a final analysis which. Is usually set out at the
- 1:29beginning. At the design of a trial and at
- 1:32final analysis. You execute everything you.
- 1:34You thought of when you designed the trial?
- 1:38This is quite a. Fixed and sometimes.
- 1:40Rigid process. Where there's no room for
- 1:42changes during the trial and these.
- 1:45Are actually exactly. Those things that might be
- 1:47innovative. Which I will talk about today.
- 1:51So why do we need to innovate trial designs?
- 1:54We are all aware. Especially in hematology.
- 1:57Of the. ERA of personalized medicine
- 2:00there are multiple drugs becoming.
- 2:02Available specific to. Subtypes of patients who have.
- 2:06A target. Mutation, for instance, for whom
- 2:10those drugs are available but in the clinical trial.
- 2:13It's usually difficult to. Enroll.
- 2:15Large subsets of. Patients when there's only a
- 2:18few. Patients who have that.
- 2:19Actual mutation. So in that era, we need to think
- 2:24of other approaches to clinical trial design and also since
- 2:28outcomes of our patients are getting so much better, studies
- 2:33take a long time to enroll patients and as a result we need
- 2:38to wait a long time for the final analysis and studies
- 2:42become expensive because of that long follow up time.
- 2:45So these are, I believe. Reasons to innovate or think of
- 2:49innovation in clinical trial designs and there's also.
- 2:54So I talked about the targeted. Treatments which are also
- 2:56biomarker driven approaches and on the other hand, when talking
- 2:59about time and costs. And we have.
- 3:01The early endpoints which is a different.
- 3:05Topic I believe. But surrogate endpoints who
- 3:07might serve, for instance, for overall survival, which MRD is
- 3:11for instance being used, those early endpoints might.
- 3:15Actually facilitate a. Sooner end of your trial, but
- 3:20that's a different topic to discuss and I'm not going to
- 3:23focus on that today. There's also another methods
- 3:26which is more important I believe is early intervention.
- 3:30For a very efficacious or a futile trial.
- 3:33And which? Is getting very.
- 3:35Hot in the last. Years is the.
- 3:38Use of external control data for your clinical trial, which I
- 3:40will. Also address.
- 3:43So when we talk about personal, personalized.
- 3:45Medicine in clinical trial designs there.
- 3:47Are three key types of trial. Design one should consider and
- 3:52the first. Is the basket.
- 3:53Trial which? Is a type.
- 3:55Of trial which? Usually.
- 3:57Enrolls multiple diseases where there's one targeted
- 4:00intervention. Specific for usually.
- 4:03Mutation and that common target is is investigated in such a
- 4:09trial but. Such a trial could.
- 4:10Include solid oncology. Patients with also hematology
- 4:14patients. And it's really a mixed bag of.
- 4:16Different types of diseases. On the other hand, we have also
- 4:21umbrella trials. Which is usually for a single
- 4:24disease, but within. That single disease when there
- 4:27are multiple targeted interventions available, those
- 4:30targeted interventions are investigated in such a trial and
- 4:34in in these. Types of trials.
- 4:35There could even be a randomization.
- 4:38Both of these trials basket. Trials and umbrella trials.
- 4:42Are early phase trials usually? Phase one or phase two clinical
- 4:45trials? Mostly phase two clinical trials
- 4:49during the COVID-19 pandemic, platform trials have become
- 4:53very. Popular where there's.
- 4:55A continuously running standard of care arm where there.
- 4:59Are always. Patients receiving that standard
- 5:01of care and when there, when there are becoming
- 5:04interventional treatments, alternative treatments
- 5:06available, patients are at that point could be randomized to
- 5:10that intervention and there are in the platform trial.
- 5:14Usually a couple. Of interim analysis where at
- 5:18that time an intervention is reassessed and when there's a
- 5:22clear sign of. Efficacy or futility?
- 5:25That drug, that intervention is dropped.
- 5:29These trials are attractive because if you.
- 5:31If you design it properly, the the standard of care arm could
- 5:35run for. Multiple years.
- 5:36And when available, different types of.
- 5:39Drugs or. Experiments could be.
- 5:40Added. During that trial, and this
- 5:42serves as a sort of master. Protocol.
- 5:45Which you could. Always rely.
- 5:47On when adding the new treatments.
- 5:50These types of trials are a bit more.
- 5:52Difficult to design when you talk to your statistician, but I
- 5:57really encourage you if you. Have these type of.
- 5:59Treatments within your disease. Type.
- 6:01To consider these. Trials because the.
- 6:04Standard of continuously running, standard of care arm is
- 6:06very attractive. The next thing I want to address
- 6:12is, like I mentioned, the early intervention for and very.
- 6:15Efficacious or futile trial? No one wants to do a.
- 6:19Trial who? At the end.
- 6:20Is is either. Very negative.
- 6:23Or. Very positive and always comes
- 6:26the question if you could have seen that coming and these type
- 6:30of. Trials are called.
- 6:31Adaptive trial designs and the example I want to highlight here
- 6:36is based on the whole phone data and this is an example in
- 6:39multiple myeloma. Where the trial?
- 6:42Randomized 2 two treatment arms, a control treatment arm versus
- 6:46an intervention arm, and at the design of the.
- 6:49Study it was. Estimated that 668 patients
- 6:54needed. To be enrolled.
- 6:56And at final analysis. The result?
- 6:58Was quite disappointing because there was no difference between
- 7:03the experimental and the control arm.
- 7:05We questioned whether we could have seen this coming and
- 7:07whether. If we could.
- 7:09Introduce interim analysis. Maybe have?
- 7:12Changed the course in this. Trial retrospectively I.
- 7:15Will show you 2 methods now. The first one is the group
- 7:18sequential design. Which actually allows you.
- 7:20To introduce interim analysis and AT interim analysis.
- 7:25You could. You could.
- 7:26Decide the based on the the boundaries.
- 7:28I will show you whether a trial. Should be continued.
- 7:33And in this example, we introduced 2 interim analysis.
- 7:36The first interim analysis was when there were still patients
- 7:39being enrolled and at the second interim analysis.
- 7:43We observed. That all patients were already
- 7:45included. But at 2:00.
- 7:46Thirds of events we had still some follow up time to monitor
- 7:52and if you for instance could consider at the first interim
- 7:54analysis to stop the trial. You would actually.
- 7:57Save patients from a potential futile or.
- 8:00Efficacious treatment and. At the second interim analysis,
- 8:04you could primarily say follow up time.
- 8:07So if we. Again retrospectively.
- 8:10Apply this to the. To this hopeful multiple myeloma
- 8:13trial, you'll see interim analysis one, interim analysis
- 8:16two, we were not able. To firmly say that this.
- 8:19Trial was going to be a negative trial and we should stop the
- 8:22trial. And a key concept of the group
- 8:24sequential design is that when more data are being observed,
- 8:28the bounds of efficacy and futility.
- 8:31Are getting. Closer, In other words, your
- 8:33estimate of of the data is getting more precise and
- 8:37therefore you're more. Precisely to say.
- 8:39If your trial is going to be still promising or whether your
- 8:42trial is going to be a negative trial.
- 8:44At the final analysis, we did not observe any difference.
- 8:47Another approach we introduced. Here is a sample size. 3
- 8:51estimation, design and what? Is really attractive here is
- 8:55that when you. Are conducting your.
- 8:57Trial. You're reassessing your power,
- 9:01and the power is important when designing a trial because you
- 9:04want to be sure you want, you want to have some.
- 9:06Probability that your. Trial is actually going to be
- 9:09showing a real effect and when the.
- 9:12Power is very high. Above 90% usually.
- 9:16That's a very favourable result and.
- 9:17That's a scenario where you could consider.
- 9:19Stopping your trial for efficacy.
- 9:22On the other hand, when your. Trial is at.
- 9:24Below 30%. Which is a probability of 30.
- 9:28Percent that you're going to. Observe a real.
- 9:30Difference. That's considered a futile
- 9:32trial. And then usually a trial is
- 9:34stopped and the promising zone is the interesting zone where
- 9:38and that's. Usually set at.
- 9:39Between 30 to 90%. Where the sample.
- 9:42Size is being re. Estimated.
- 9:44So during your trial, you. Have the feeling that this trial
- 9:47might have some interest, but at that time you're not sure
- 9:52definitely. Not sure whether.
- 9:53Your trial is going to show that eventually and then you could
- 9:56enroll additional patients. You could re estimate your
- 9:59sample size and in this scenario that could have been resolved in
- 10:031/3 of additional patients in your trial.
- 10:07When we calculated the conditional power, and we did
- 10:10that at the second interim analysis, we found that this.
- 10:13Study actually had. 17% conditional power, meaning that
- 10:18this trial was very unlikely. To show efficacy.
- 10:21And actually was futile and therefore in this scenario
- 10:25retrospectively again. We could have decided that this
- 10:29trials should have stopped. Which in this case because it
- 10:32was after already. 2/3 of. Events, meaning the trial was
- 10:37already completed for inclusion. But it could have saved.
- 10:40Follow up time. These are the.
- 10:44Adaptive trial designs. We also recently.
- 10:48Used a Bayesian type of analysis to.
- 10:50Investigate whether we could. Improve decision making in a
- 10:53clinical trial by using a Bayesian methodology.
- 10:58The basin methodology. Is has three key concepts
- 11:03consisting of a prior. Which is the belief what you
- 11:07have before you start on a. Trial.
- 11:09And this is, for instance, a complete remission rate you
- 11:11expect for a leukemia patient. Which is usually.
- 11:15After induction treatment, about 80 percent, 85%.
- 11:18And when you observe additional. Data in In a very positive
- 11:21trial, you might. Observe a very.
- 11:22High remission rate, for instance.
- 11:24Updated likelihood. Your guess what you observe is
- 11:27is better, so your updated. Belief is.
- 11:30In between, that's the posterior.
- 11:32And that's a key concept of Bayesian analysis, which.
- 11:36I will show. You how that performed in our
- 11:38AML analysis and this is again maybe a disappointing hopeful
- 11:43example. But it helps to use these.
- 11:45Examples. To investigate what what could
- 11:49have changed? And if we looked in this.
- 11:51Trial this was. The whole from 132 trial we
- 11:54randomized almost 800 patients between a controlled treatment
- 11:59and experimental treatments and we observed clearly no
- 12:03difference, however, at the design of the study.
- 12:07The expected hazard ratio for benefit.
- 12:09Was .76. While the observed.
- 12:12Hazard ratio was .99. And again, we questioned what
- 12:16we've seen at this coming when we introduced interim analysis.
- 12:19So that's what we did. We introduced 4 interim analysis
- 12:22and when using that group, sequential design.
- 12:24We actually observed that. At the third interim analysis,
- 12:28the fertility bound was crossed. So at the third interim analysis
- 12:31after 450 patients we using. This type of.
- 12:36Adaptive designs might have considered to stop the.
- 12:39Trial because efficacy. Was never going to be shown.
- 12:44However, if we. Use a Bayesian analysis and one
- 12:48of the strengths of Bayesian analysis.
- 12:50Is that you're also able. To reinforce your control arm by
- 12:53adding additional patients. And we use the previous.
- 12:57Hopeful trial also including AML patients.
- 13:01We actually showed. That using that Bayesian
- 13:06approach after the first interim analysis.
- 13:08So after 150 patients there was a 1.2%.
- 13:12Probability of being. Successful of being able to show
- 13:16that .76 expected hazard. Ratio we had.
- 13:20At the beginning of the trial. So using a Bayesian analysis and
- 13:24reinforcing your control arm, we were.
- 13:28Able to show that that trial was already.
- 13:30Very early, going to be a negative trial.
- 13:34So these are. Examples of methods to introduce
- 13:37interim analysis which might really.
- 13:39Help you. During a trial.
- 13:42To to be sure that you're. Able to demonstrate the beliefs
- 13:46you had when you designed the trial.
- 13:50External control data, I mentioned that at the beginning,
- 13:53are increasingly being used, and we also investigated thinking of
- 13:57the Bayesian analysis. Where you're able to.
- 13:59Reinforce your control arm if you're.
- 14:02Able to. Use external control.
- 14:04Data whether that helps to compare to.
- 14:06Reinforce your control arm. But the question is, are
- 14:10external control? Data really helpful.
- 14:13Are those really comparable? To your clinical trial.
- 14:16So we again I used an approach. Where we.
- 14:20Took the control arm of a hopeful trial and we.
- 14:23Sought for. External control data to
- 14:26reinforce the control arm and we identified 2 potential
- 14:30alternative. Data sources.
- 14:32The 1st is the. Harmony and Alliance data.
- 14:34Source. And the other is a.
- 14:36Truly real world data set. Of patients gathered in the in
- 14:40the Netherlands by the Dutch Cancer.
- 14:42Society, who also received the same.
- 14:44Intensive AML induction treatments and we questioned
- 14:48whether the control patients of the clinical.
- 14:51Trial were actually similar to the.
- 14:53External real worlds control data arms and when we looked for
- 15:00baseline characteristics, we clearly, and that's not
- 15:03surprising, observed differences.
- 15:06Missing data was much more common in the real world data
- 15:08source, but also within the harmony.
- 15:10Data source and. When we performed the matching
- 15:13methods, we. Observed this is overall
- 15:15survival that. Outcome for the whole phone
- 15:18control. Arm was actually.
- 15:20Similar similar compared to the Harmony data.
- 15:23But I have to acknowledge that the harmony data is basic.
- 15:26Is basically a data set. Who consists?
- 15:28Of the majority of clinical trial patients.
- 15:30And in this case, in our analysis, we found that about 60
- 15:35to 70% were actually enrolled in a clinical trial.
- 15:39However, the real. Data from the Dutch Cancer.
- 15:41Society. Those patients.
- 15:44Clearly performed worse. 10% worse.
- 15:46Survival Overall survival at two years.
- 15:50When compared to hope and controls and we really believe.
- 15:53That this is due to. To various reasons, but for
- 15:56instance the missing performance status.
- 15:58How? Fit is your patient, and is it
- 15:59really a patient who could also be?
- 16:02Included in a clinical trial? Is it comorbidity?
- 16:05Data all all types of. Data that are not available in a
- 16:09real. World data set so we are really
- 16:11hesitant to firmly say that real real world data could actually.
- 16:15Supplement the data in a clinical trial at this.
- 16:18Stage so I hope to have show. You that innovative trial
- 16:24design. Is the future.
- 16:26And with the personalized medicine becoming available now
- 16:30we need to. Adapt our trials according to
- 16:32the. Needs to the accelerating needs
- 16:34within the clinical trial development.
- 16:37To deliver the right drug. For the right patient at the
- 16:40right time, adaptive designs I've I've shown you could help
- 16:45you. For potential and early trial
- 16:46intervention. External data might reinforce
- 16:50your control arm and important in that.
- 16:52Perspective, but. You need to define and identify
- 16:57the right and the proper external control.
- 16:59Data set. And with all this, and
- 17:01especially if you want to adapt your trial during the conduct of
- 17:04your trial, you need a solid trial infrastructure.
- 17:08Where you have. Immediate data available and who
- 17:11can support the complex trial that you might design?
- 17:17And with that, I would like to conclude.
- 17:18Thank you.