Trials can seem complex. Get the basics here.
Haematology research nurse Dominic Conroy explains trial phases.
The specialist terminology associated with clinical trials can be confusing, and whether you’re reading the news or hoping to enrol in a trial, it helps to understand the concepts. Here’s a primer:
Many drug studies are divided into three distinct stages of clinical investigation. This type of study is called a “Phase 1-3 trial”.
When researchers evaluate new treatments, their first aim is to explore the safe dose range of the drug, and this is the principal aim in Phase 1. These studies usually recruit patients in very small numbers and the data collection process tends to be more intensive than for later-stage trials. People receiving new treatments in a Phase 1 clinical trial may be required to spend several days either in inpatient or outpatient hospital settings to allow staff to monitor them closely for their ongoing response to treatment. The staff also collect blood samples frequently, both to ensure patients’ safety and to determine how the treatment is working.
New treatments demonstrating a certain degree of safety and reliability are considered safe to test in a larger group of people, and the trial can move to Phase 2. In this phase researchers recruit greater numbers of participants, normally about one hundred individuals in total.
Treatments move to Phase 3 once researchers have acquired a reasonable level of safety data and determined that the drugs have demonstrated a certain degree of effectiveness. The main aim of Phase 3 studies is to explore the effects of standard versus new treatments in larger populations than in earlier phase studies. Thousands of patients can be recruited to Phase 3 studies, which often take place internationally across many centres. Confusingly, data from ongoing Phase 2 studies can continue to inform successive Phase 3 studies, and there may be some relay of information between clinical studies at different stages of investigation.
Clinical trials can vary greatly in terms of the demands they place on patients’ time, though study visits for most Phase 2/3 trials are often not significantly more involved than regular clinic visits. If you are thinking of enrolling in a study, it’s important to discuss just what participation will involve with your haematologist or trials nurse.
Trials involve risks, but they have tremendous benefits for patients. It’s an opportunity to join the search for better treatments, and perhaps one day a cure.
The JAK 2 inhibitor is working incredibly well for me.