Clinical trial design and how it can be used to improve the patient experience

While it’s true that the perfect trial design doesn’t yet exist, where should the extra burden lie — with patients or the industry? Let’s take a closer look at the different types of clinical trial design.

#1 Single-arm trials

These trial designs only have one treatment option, with no placebo, and are usually in clinical fields such as cancer or stroke where patients experience acute illness and may not have many treatment options available to them. In these circumstances, it can be considered unethical to offer patients a placebo due to their medical requirement. Patients in this population may be reliant on caregivers for support, such as transport to and from study visits or providing consent on their behalf.

Trial designs like this can be beneficial and more attractive to potential participants. This is because the patient will know what treatment they will be receiving, and its associated risk/benefit profile. This can make the study more attractive by removing the unknown elements of randomisation and blinding by being open-label, as well as allowing early access to new drugs for patients that may be desperately seeking options for their condition.

#2 Randomised controlled trials (RCTs)

These trials usually have two options, and this has long been considered the gold standard of clinical trial design as it compares the new treatment against a placebo or the current standard care option. Randomisation is used to assign patients to either arm, and blinding is often in place to prevent both the clinician and the patient from knowing which treatment allocation they received.

A recent progression of the RCT is a stepped wedge design, in which patients are grouped into ‘clusters’ and then receive the study treatment sequentially, with an additional cluster being added each time until all patients are receiving treatment. Hence the design name — the intervention group increases in size as the trial progresses. These trial designs are particularly useful where there is evidence to support the intervention in providing more benefit to the patient group than risk of harm. In these circumstances, the lowest risk group would be given the intervention first, followed by the next lowest risk group, and so on, providing the data supports this.

Without clear explanation, some of the terms I’ve used above can be confusing to a patient and it may not be apparent to them what the benefits of taking part in the trial are. After all, there is a 50% chance that they won’t receive the intervention treatment, so why should they take part at all? Many patients give altruistic reasons when asked about why they’d take part in a trial, but depending on your patient group and disease indication, having access to a potentially novel and effective treatment can also be a strong factor in the decision-making process.

#3 Adaptive Trials

These are the new cool kids on the block, and have rightly drawn recent attention due to their potential to make trials more flexible, cost-effective and efficient at gathering the data required for approvals. By having regular analysis ‘check-points’ to evaluate whether a treatment is safe and effective, researchers can remove drugs that aren’t working well. And in their place researchers can add in new ones, or change the dose of an existing one, based on the interim data. Ultimately, this means that patients are receiving ineffective drugs for less time and can be switched to a more suitable alternative.

The term adaptive trial is an umbrella term for several different trial designs that follow the same principles, but flexibility is key here in removing rigid protocol criteria for both sites and patients. Put yourself in the patient’s shoes — if there is more chance of you receiving a new treatment that is showing effectiveness against your disease, wouldn’t you be more likely to sign-up?

#4 Complex Intervention

Not all clinical trials are focused on new drugs. There are lots of trials that compare different interventions for treating symptoms and providing support regimes for illnesses. Therapies for patients suffering with mental health issues, physiotherapy for muscular injury, or rehabilitation fall into this category. These types of trial usually also evaluate methods of delivery — such as who gives the intervention, the timing that it is received by the patient and what effect this has on its effectiveness, as well as any impact on other factors, such as health economics and cost.

These interventions may appear less daunting to patients due to the negative aspects of new drugs and their unknown effects. These trials often require face-to-face contact with a healthcare professional or researcher, however also come with a raft of questionnaires, diaries and patient reported outcomes (PROs) that provide options for a decentralised model or collection through wearable devices.

So, what should you bear in mind when designing a trial?

When designing your trial from an initial concept, it is important to bear in mind not just the benefits that your trial has on sample size, endpoint analysis and budget, but also how this design will be perceived by potential participants. Have you considered allowing more remote visits or data collection? Or potentially using a hybrid design where patients still see a clinician, but also have option of wearables and ePRO collection through an app?

Clinical trials are evolving, and we must explore the tried and tested methods mentioned above in new ways to ensure that patient experience is at the top of our agenda, and that efficiency is considered at every stage of protocol authorship and delivery. Discussing trial design between clinicians, statisticians and patient engagement experts like COUCH Health can help to set your trial on the path to success.