Treatment with ivacaftor can lead to weight gain in CF patients with a G551D mutation, a small Australian study shows.
Weight gain was significantly related to improvement in fat intake at 16 weeks and younger age at 34 weeks, the open label phase I and phase II study from Westmead Children’s Hospital in Sydney found.
In the phase I part of the study 20 CF patients aged 6 to 48 years with established pancreatic insufficiency and a G551D CFTR mutation commenced ivacaftor 150mg twice a day for 112 days.
At baseline average weight was 52.8 kg, fat intake was 93.8g a day and fat excretion was 39.3% of intake.
But at the end of phase I average weight was 56.2kg, fat intake was 128.95g a day and daily fat excretion was 30.4% of intake.
Three out of 14 patients, who were aged 7, 11 and 17 years, improved their fat absorption into the normal range and ceased PERT in phase II part of the study (endpoint).
They have since remained off PERT and maintained normal growth and remained asymptomatic, the researchers said.
The mechanism responsible for improved nutritional status of patients was multifactorial and included improved lung function, enhanced dietary fat intake, an initial enhancement of fat absorption “and the likely restitution of exocrine pancreatic sufficiency” in three of the children, the study authors concluded.