Spring 2023

The life cycle of a clinical trial

From initial idea to lifesaving innovation, find out what it takes to bring a new treatment from the lab to patients

It’s an unfortunate fact in the world of medicine: Nine out of every 10 clinical trials—those crucial research endeavors that aim to uncover new and better ways of treating disease—fail.

But even failed clinical trials provide valuable data and insights that can fuel future forays into better medicine. And when a clinical trial succeeds, it gives doctors a new or improved weapon in their fight against a specific disease—and gives patients a dose of hope.

Good luck, good science, and good results converged last year when a clinical trial involving a team of experts at M Health Fairview Masonic Children’s Hospital helped prove the effectiveness of a new gene therapy for treating cerebral adrenoleukodystrophy (ALD), a rare neurodegenerative disease that typically affects boys.

Traditionally, ALD is treated through the transplantation of blood stem cells from a healthy donor to a sick recipient. It’s effective, but for between 10 and 15% of recipients, the procedure has fatal side effects.

Troy Lund, M.D., Ph.D., Paul Orchard, M.D., and a team at Masonic Children’s Hospital played a leading role in the 10-year clinical trial that evaluated this potentially safer approach to treating the disease.

Instead of using a donor’s cells, the gene therapy protocol involves removing some of a patient’s defective stem cells, adding in a normal copy of the previously faulty gene within those cells, and putting them back in the body where they work to disrupt the disease process of ALD. 

The results were more than promising; in September 2022, the U.S. Food and Drug Administration approved the gene therapy for wider use to treat ALD. Later this year, Masonic Children’s Hospital will become one of the four locations in the world to offer the treatment to patients.

“A trial like this really fulfills our promise as physician-scientists,” says Lund, whose work has been supported by the nonprofit X Out ALD. “Our goal is to take ideas and observations from the lab, develop therapies, bring them to patients, and have successful outcomes. It’s fantastic when it all works out.”



Lab research
Clinical trials often take shape in the laboratory, where researchers work to understand the mechanisms of disease on a cellular level. Whether under a microscope or in a petri dish, discoveries in the lab fuel further investigations.


Preclinical models
When an idea for a new treatment emerges in the lab, it’s first tested in animal models to verify its safety and initial effectiveness.


Therapy development
If a potential treatment is found to be safe and effective in animals, then scientists can begin developing the therapy for people.


Phase I, II, and III clinical trials
Phase I, II, and III clinical trials introduce the therapy to increasing numbers of people, while asking important questions such as, “Is this treatment safe? And if so, is it effective?” For the ALD gene therapy, the answers were “yes” and “yes,” allowing the clinical trial to advance to the next stage. For many other trials, however, this is where the process comes to a halt. Some new treatments may cause dangerous side effects, or they might not be as effective as predicted. When that happens, scientists and doctors take what they’ve learned and begin to forge a different path toward treatment success.


FDA approval
Should a new treatment prove to be safe and effective through three phases of the clinical trial, the FDA gives it a stamp of approval. From there, more health care providers can offer the treatment—and more patients can benefit.


New treatments
Even after a new treatment is approved, it continues to be monitored for long-term effectiveness and unforeseen side effects. This is known as Phase IV of the clinical trial. Information gleaned during this phase allows physicians to fine-tune treatments and learn more about the disease.