A researcher-patient’s plea for broader inclusion in cystic fibrosis trials.
I’ve always known cystic fibrosis (CF) is a progressive disease; it destroys lung cells, tightens the small airways in the bottom of my chest, and each day takes me closer to the time when it will have ravaged my lungs. I had never really questioned if there was some way this process could be altered. I accepted that it couldn’t.
Recently, however, this has changed. The epicenter of new CF research is the development of medications that will slow, stop, and hopefully even reverse the effects and damage that CF inflicts on the body. The possibility of the cells in my lungs functioning to their full potential — with CF transmembrane conductance regulator protein function restored and working correctly, expelling chloride out of my cells, hydrating the surface of my lungs, and halting the thick sticky mucus that has caused my airways to be enveloped in a suffocating cloak for all these years — is like a feeling of being rescued when you are drowning.
Unfortunately, I am still drowning.
“I’m very sorry, Ms. Balasa, but you will not be able to be a participant in this clinical trial.” This was the response I received during one of my searches for these drug trials. Excited by the possibility of participating, finding one recruiting at my local adult clinic, I reached out to study coordinators and was informed that I met all but one criterion to participate in the studies. This specific criterion has prevented me from prior trial participation involving other investigational medications treating the symptoms of CF, including anti-infectives and anti-inflammatories.
Most CF studies, including phase I, II, and III trials, require a lung function minimum of at least 40% FEV1 (forced expiratory volume in one second). My FEV1 is 25%, so I am excluded from these trials. Many patients face a similar situation. The 40% threshold biases samples toward a young patient population, as this degenerative condition causes steadily decreasing lung function with time. Furthermore, as CF treatment has rapidly progressed and increased patients’ life expectancies, there are now more adults with CF in the U.S. than children, according to the CF Foundation Patient Registry.
As a patient who works in the science field, I started to ask myself: Where does that number come from? Should this one variable be such a deciding factor? Are we getting comprehensive results from these studies if a subset of patients is omitted? Are investigators using eligibility criteria from a prior study without determining whether the exclusions are scientifically justifiable?
There are safety concerns to consider when thinking about including patients with a lung function below 40%. Those with lower lung function have a higher chance of illness during the trial period because of disease progression or possible adverse effects from the drug. Additionally, patients who are more ill most likely will not have the same level of symptom relief and disease reversal as someone with less scar tissue and damage to the lungs. These patients may not have a significant change in lung function, and for the drug company, this means fewer positive data results to present to the FDA.