A Swiss study reveals that children with cystic fibrosis on Trikafta experience rapid weight gain closely associated with decreasing inflammation, providing new insights into the therapy’s benefits over time.
In children with cystic fibrosis taking Trikafta, weight gain appears to move in step with falling inflammation, according to a Swiss study published in Respiratory Medicine.
Researchers followed 59 children and adolescents aged 6 to 17 who were starting elexacaftor/tezacaftor/ivacaftor, the triple-combination therapy marketed by Vertex Pharmaceuticals. The team said the findings suggest that early and longer-term increases in body mass index were linked to reductions in both whole-body inflammation and intestinal inflammation.
The change was visible quickly. Within 1 to 2 weeks of treatment, body mass index had already improved, and most of the gain came during that early period. After a year, the improvement was still present, while inflammatory markers were lower than before treatment began.
The study adds to earlier evidence that Trikafta can influence weight in different ways across cystic fibrosis patients. A 2023 study in Respiratory Research found that weight gain after starting the drug varied by baseline body size, with underweight patients gaining the most and overweight patients the least. More recently, a 2025 cohort study in the Journal of Cystic Fibrosis reported that better lung function and lower faecal calprotectin, a marker of gut inflammation, were associated with rising body mass index in children and adolescents on the therapy.
In the Swiss study, blood tests showed lower levels of leukocytes, or white blood cells, after treatment started, suggesting less systemic inflammation. Stool tests also showed reduced calprotectin, pointing to less inflammation in the intestines. The researchers said these patterns may help explain why nutritional status improves on Trikafta, although they stressed that body mass index does not fully capture body composition and that the study lacked a control group.
Disclaimer: This content is for informational purposes only and is not intended to be a substitute for professional medical judgment, advice, diagnosis, or treatment.
