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Clinical Trials Process

There are currently hundreds of gene therapies in clinical trials for different diseases. Clinical trials research the way a drug or treatment will interact with the human body and whether it is safe and effective. Learn more below about the process of a clinical trial and how to access these potential treatments.

Clinical Trials Process

Preclinical study happens before a clinical trial starts. The treatment is tested either in cell models or animals. These studies check if the treatment will work and how much of it is needed to see a positive effect. It also tests the safety by looking for any negative effects. If the preclinical results are promising, the researcher then designs the study for humans.

An Investigational New Drug (IND) application is then submitted by the researcher to the U.S. Food and Drug Administration (FDA). The FDA strictly reviews how the treatment is made, the preclinical data and the clinical trial design. They make sure the researcher has done everything possible to minimize risks to the study volunteers. Once the FDA agrees that risks to volunteers are minimized, a clinical trial can be put into action.

Clinical trials are conducted in phases. Every phase is modified to help answer a different question to better understand the treatment. Safety is a priority in each phase. If a study is not deemed safe, it will not move on to the next phase. This includes monitoring for adverse events, which are any unexpected health problems ranging from minor to serious. The researcher collects information on whether the event relates to the treatment, the severity, frequency, and how to resolve it. In turn, these become the expected side effects to be aware of.

  • GT-3-Illustrations-03.pngPhase one tests if the treatment is safe for a small number of patients. Sometimes it also can determine the right dosage to be given.

  • Phase two expands the number of patients receiving the therapy and determines if the responses to the therapy are favorable or useful while still monitoring safety.

  • Phase three typically lasts the longest. In this phase, the main goal is to prove that the treatment gives the desired result while being safe in an even larger group of patients.

  • Some phases can be combined to make the evaluation process more efficient. This is done for serious and rare diseases for which there is a clear unmet medical need, meaning a disease whose treatment or diagnosis is not addressed adequately by available therapy. This is explained more below in the “FDA Efforts” sections.

Eligibility criteria are characteristics that all participants must have. For every clinical trial there is unique criteria for who can and cannot participate in the study, these are also called inclusion and exclusion criteria. These commonly include age, gender, specific gene mutation, medical history and more. By making sure that volunteers meet these criteria researchers can better understand results of the clinical trial.

Finally, a Biologics License Application (BLA) is submitted to the FDA if the results of the final phase of the clinical trial are showing the treatment to be safe and effective. Following thorough review, the FDA makes a final decision about whether the treatment will be approved to use. This is when a treatment becomes “FDA-approved” and is made available to the public.

Patient Access

Topic-4-Illustrations-03.jpgOnce a treatment successfully passes through clinical trials and is approved by the FDA, then how can patients access it?  

Only available at specialized sites. Currently, FDA-approved gene therapies (such as Luxturna or Zolgensma) are offered at a limited number of sites. These sites are academic medical centers with providers that are specially trained and experienced at giving the treatment.

Talk with your doctor. It’s important to inform your healthcare provider about potential clinical trial participation, while you may also reach out directly to a medical center that offers the therapy. Your provider may also be involved in post-procedure care and answering questions along the way.

Check insurance coverage. The currently available gene therapies are covered by many health insurance options. Interested patients should contact their health insurance provider to determine its coverage and what to expect for out-of-pocket costs. Manufacturers of the gene therapies often offer patient support services to assist in the process.

Finding a Clinical Trial

Participating in clinical trials is a way to receive an investigational product, while moving along research to help others who have the same disease or condition. If you are considering a clinical trial here are some steps you can take to access them:

  • Explore the ASGCT Clinical Trials Finder to search for open clinical trials in gene and cell therapy.

  • Talk to your doctor.  Even if you find a clinical trial on your own, it is still important to talk with your doctor about it.

  • Sign up for a patient registry. Patient registries are a collection of information about patients who share a condition or experience. The goal is to help medical researchers better understand how diseases develop and progress over time. Some registries invite people to sign up to be contacted about participating in clinical research. Here’s a helpful list of patient registries from the National Institutes of Health (NIH), along with The National Organization for Rare Disorders (NORD) Registry Program, The Coordination of Rare Diseases at Sanford (CoRDS) and the Rare Diseases Registry Program (RaDaR).

  • Connect with patient organizations. Organizations such as NORD and Global Genes, or patient groups for specific diseases are a great place to start. They are hard at work to support rare genetic diseases and can be a great way to get updates and advocate for disease research.  

FDA Efforts

Between preclinical study and clinical trials, the process can take many years to conclude. Clinical trials alone sometimes can take eight years or more. There are many factors that go into that duration including study planning, authorization to run a trial, ethics review, funding, research materials such as patient information, consent forms, and monitoring systems. However, FDA provides various expedited pathways (Fast Track, Breakthrough Therapy, Regenerative Medicine Advanced Therapy, Accelerated Approval, Priority Review) to accelerate the process for therapies that meet certain criteria while still maintaining safety.

Sometimes the three phases of a clinical trial are combined to make the evaluation process more efficient. The treatment may be made available more quickly for serious and rare diseases for which there is a clear unmet medical need, meaning a disease whose treatment or diagnosis is not addressed adequately by available therapy. There are some challenges to making this process shorter. Researchers need to avoid giving multiple patients too low of a dose to work or a toxic dose. They also need enough time to fully assess the results of a trial whether benefits outweigh risks. It all goes back to making sure that the treatment is well understood, and safe and effective enough to be approved for the public.

Explore more resources on our website about the basics of gene therapy, gene therapy for specific diseases, helpful insights on the patient journey, and clinical trials information.

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Last Updated: 04/12/2021

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