According to a story from statnews.com, Ella Balasa, who has cystic fibrosis, has been seeking to join a clinical trial in hopes of finding a new treatment that can help slow or halt the progression of her disease and save her life. Unfortunately, she has not been permitted to join any trials that she has inquired about so far. This is because most clinical trials require a minimum degree of lung function, a measure called forced expiratory volume per second, that Balasa does not have.
About Cystic Fibrosis
Cystic fibrosis is a type of genetic disorder which can have impacts throughout the body, but it is most characterized by the build up of abnormally thick, sticky mucus in the lungs. This mucus becomes a fertile breeding ground and habitat for potentially infectious bacteria. Many patients must take antibiotics for much of their lives. This disorder is caused by mutations of the CFTR gene. Symptoms of cystic fibrosis include progressive decline in lung function, lung and sinus infections, coughing up mucus, fatty stool, poor growth, infertility in males, clubbed digits, and digestive problems. Treatment includes antibiotics and medications or procedures intended to maintain lung function. Lung transplant is an option when lung function declines severely. Life expectancy ranges into the 40s and 50s with good care. To learn more about cystic fibrosis, click here.
Forced expiratory volume per second gives a percentage of lung function compared to what is regarded as normal function. Balasa retains only about 25 percent of her lung function according to this measure; most cystic fibrosis trials require patients to have a minimum of 40 percent.
Is One Number All it Should Take to be Excluded?
It seems tragic that one simple measure is all it takes to disqualify someone like Ella Balasa from participating in a trial. Perhaps there are some scientific or safety reasons for having this limit; after all, it may be easier to more accurately understand data when all patients are being treated from a certain minimum threshold. More severely affected patients are also more likely to see their disease worsen or even die during the trial, which would not be good publicity. However, relying on a single criteria also has serious limitations.
Variations in Cystic Fibrosis
Cystic fibrosis does not manifest in every patient in the same way. Despite her lower lung function, Balasa can still do many day to day activities; there are patients with higher forced expiratory volume per second who are actually far more debilitated. These limits also simply exclude a large number of patients; more cystic fibrosis patients are surviving longer, meaning that a greater percentage have lower lung function.
Ultimately, the entire point of drug development and the medical system should be to help people that are sick. It seems logical that more than a single factor should be considered when selecting trial participants, and that no single factor alone should be an automatic disqualification.
