‘Significant’ Levels of Pain Reported by Fabry Patients in Large Survey

Even with treatment, people with Fabry disease often experience pain to an extent that it affects their quality of life, a study based on a survey of more than 350 patients reports.

Diarrhea was also a commonly reported problem, but more often in male respondents than female.

“Symptoms and Quality of Life in Patients with Fabry Disease: Results from an International Patient Survey,” was published in the journal Advances in Therapy.

Understanding the experiences of people with Fabry disease is important both for providing good medical care and for designing meaningful clinical trials. In testing a possible treatment, it is necessary to understand what a ‘baseline’ experience looks so you can see if there’s a meaningful change.

For this reason, Idorsia Pharmaceuticals sponsored a survey of people with Fabry disease in support of their ongoing Phase 3 clinical trial (NCT03425539) of lucerastat — a potential oral substrate reduction therapy that aims to block production of globotriaosylceramide (Gb3), the fat molecule that accumulates in the tissues of Fabry patients. Prior to July 2018, the survey was funded by Actelion Pharmaceuticals.

In total, 367 people completed the survey, which mainly included quantitative questions about symptoms and experiences (like rating pain on a scale from 1 to 10). Respondents were predominantly female (245 female, 120 male, 2 unspecified), most were from the United States or Canada (247, 67.3%), and they ranged in age from 18 to 80 years, with most (195, 53.1%) between the ages of 41 and 60.

Most of the respondents (291, 79.3%) reported that, at its most severe, Fabry-related pain was 4 or higher on a scale from 1 to 10, which the researchers classified as moderate (4–7) or severe (8–10). More than half of the respondents (199, 54.2%) reported experiencing pain at least once or twice a week, and 309 (84.2%) reported pain in their hands and feet.

No differences in reported pain was seen between the two sexes, but moderate-to-severe pain was more common among younger respondents.

The same was observed for moderate or severe pain in the hands and feet, which was greater in people under 40 years old (113/126, 89.7%) and tended to lessen in those over 60 years old (35/46, 76.1%).

Use of enzyme replacement therapy (ERT) did not seem to impact pain; 225/280 (80.4%) of people on ERT reported moderate to severe pain, as did 63/84 (75.0%) of those who were not taking ERT. Rates of pain in the hands and feet were also similar in both groups (83.6% and 85.7%, respectively).

Predictably, respondents who reported more severe and frequent pain also reported that their pain had a greater impact on quality of life, interfering with daily activities, sleep, interpersonal relationships, and general enjoyment of life.

Frequent diarrhea (more than once per week) was the most commonly reported gastrointestinal side effect, and it was reported by disproportionately more male than female respondents (39.2% vs. 23.3%). In contrast, frequent constipation was more common in females than males (24.5% vs. 4.2%). Gastrointestinal symptoms also appeared to be independent of ERT use.

Because of the surveyor’s interest in clinical trials, patients were also asked about their attitudes toward participation in such trials. Generally, attitudes were positive: nearly a third (115, 31.3%) reported already having participated in trials, and more than half reported being comfortable giving biopsies, being in the hospital overnight, and other activities that may be required of participants in clinical trials.

Importantly, 35.7% (101/283) of the people who were on ERT said they would be willing to discontinue ERT to take place in a year-long trial, while 24.0% (68/283) said they would not be willing to do this. Others were unsure.

“Patients with Fabry disease who participated in this large, international survey experience significant Fabry-specific pain, independent of sex or ERT use,” the researchers concluded. “These results suggest that the healthcare needs of patients with Fabry disease are not being fully met, and additional treatments are required to improve symptoms and quality of life.”