Background The benefits of Elexecaftor-Tezacaftor-Ivacaftor (ETI) therapy on the health and wellbeing of people with CF (pwCF) are well documented. Since approval, however, a growing number of potential side effects have emerged in reports from clinical practice. With current understanding of ETI tolerability limited to data from clinical trials, the prevalence of side effects and their impact on care decision making remains poorly categorized. Methods A ten-question survey was developed and distributed to patients 18 years or older who were treated at the Massachusetts General Hospital CF centers. Reports of side effects were measured across twelve distinct categories, and dose adjustments and discontinuation due to side effects were collected. If a patient reported no side effects, they did not have to complete the entire survey. Results Among ninety-two respondents initiated on ETI, 51 respondents (55.4%) reported potential side effects and 41 (44.5%) respondents reported no adverse events. The most commonly reported side effects were mental health, changes in appearance, and gastrointestinal complaints, which were reported by 22.8%, 30.4%, and 21.7% of patients, respectively. Eighteen (19.6%) respondents modified their dosing in response to side effects, and six discontinued treatment permanently (6.52%) due to persistent side effects. Conclusions Responses demonstrated marked heterogeneity, with most respondents reporting at least one side effect following initiation. Dose modification was commonly utilized to mitigate adverse effects, however few respondents had to discontinue treatment. These findings demonstrate the importance of monitoring for potential drug-related side effects of ETI in clinical settings.

Background International consensus statements on depression and anxiety in adolescents and adults with CF recommend assessment for comorbid substance misuse. However, at CF centers, the frequency and impact of substance misuse have not been well characterized, and best practices for prevention, identification, and evidence-based treatment have not been routinely implemented. Methods Medical records of 148 adults with CF over 3 years were reviewed to determine the prevalence of substance misuse (alcohol or opiates) and its relationship with clinical variables and healthcare utilization. Independent-sample t-test for continuous outcomes and chi-square test for binary outcomes were used to compare groups with and without substance misuse. Results Substance misuse was documented in 28 (19%) adults with CF, equally distributed between alcohol (n=13) and opiates (n=15). Adults with substance misuse were more likely to be male. The prevalence of diagnosed anxiety and depression did not differ significantly between groups, but those with substance misuse had more severe anxiety (GAD-7: 10.0±6.1 vs. 3.3±4.4; p<0.001) and depressive symptoms (PHQ-9: 10.4±6.5 vs. 4.0±4.8; p<0.001). Adults with substance misuse had higher annual rates of missed outpatient CF visits and inpatient hospitalizations, with hospital admissions of longer mean duration. Conclusions In adults with CF, substance misuse is common and is associated with adverse indicators of emotional and physical health and service utilization, suggesting that systematic approaches to addressing substance misuse in CF clinics should be considered. Prospective, longitudinal study is warranted to elucidate the complex relationships between depression, anxiety, substance misuse, and health outcomes in individuals with CF.