Sex Differences
Researchers are looking at sex differences in CFTR modulator response, as it is known that females with CF may have reduced median life expectancy and other risk factors for worsened disease, compared to males. In the GOAL study (G551D observational study) of iva, a new analysis in pwCF ≥ 6 years of age, with at least one G551D mutation, differences in outcomes beyond FEV1pp were examined by sex41. In 144 patients, with a mean age of 21.6 years, the key findings were that sweat chloride declined more in females after 3 months of treatment (-55.5 mEq/L versus -48.8mEq/L, p=0.045), and the reduction in sweat chloride correlated with baseline weight in females. PExs declined significantly in females (1.7 to 0.9 PEx/yr, p=0.024), compared to a non-significant decline in males (1.1 to 0.8 PEx/yr, p=NS). At an individual level, more females had a decline in PEx rate (46.3% versus 27.3%, p=0.024). When exploring results based on age, patients <18 years had similar response in males and females for weight, sweat chloride, but for those ≥ 18 years, women had lower mean baseline weight, and a greater sweat chloride reduction with iva. Understanding disease differences in males and females with CF is an important part of adequately treating this disease. Examining differential effects of CFTR modulators based on gender will be imperative, to assure that the therapeutic benefit is adequate in both sexes.