Progress to find treatments for polycystic kidney disease is partially driven by patient involvement in clinical studies. According to clinicaltrials.gov, “A clinical study involves research using human volunteers that is intended to add to medical knowledge.”
Types of clinical studies
The two types of studies currently underway for PKD patients include observational studies and interventional studies.
Observational studies monitor and record various clinical and/or subjective factors over a period of time, like blood pressure, GFR, or pain. This is done to better understand how PKD progresses. Involvement includes activities such as having conversations with researchers or physicians, or recording daily events in journals. No drugs are given or other interventions are made to alter the course of the disease.
Interventional studies monitor and record various clinical and/or subjective parameters by testing experimental treatments, devices or combinations of drugs that may alter the course of the disease. Participants receive specific interventions such as drugs or devices, procedures, or changes to participants’ behavior such as diet. The purpose of an interventional study is to test a new drug or other intervention for safety and effectiveness in treating the disease in question before it can be prescribed for patients.
Phases of a clinical trial
The U.S. Food and Drug Administration (FDA) is the federal agency charged with oversight of all the clinical trials going on in the U.S. at any time. A new drug to treat PKD must move through each stage before it can be reviewed for approval by the FDA. The FDA defines the phases for the clinical trials.
- Phase I – The new drug is tested for safety and side effects in a small number of healthy volunteers with PKD.
- Phase II – The new drug is tested for safety, dose ranging and preliminary effectiveness in a small number of volunteers.
- Phase III – The new drug is tested in a large number of volunteers with PKD to establish effectiveness, monitor side effects and compare results with current treatments. The data collected during the clinical trial is analyzed and then submitted to the FDA for regulatory review, which can take one to three years. If there is an intent to apply for an NDA (new drug application), it is communicated to the FDA and shapes the design of the study. Once it is approved, the new drug can be prescribed by physicians to treat PKD.
- Phase IV – These studies are done after the drug has been approved by the FDA and it is in use (considered a post-marketing study). Additional information about risks, benefits and optimal use is collected and analyzed.