Evolution of dry powder inhaled colistimethate sodium (Colobreathe®) in a large adult cystic fibrosis centre

Objectives: Colobreathe® is a dry powder formulation of colistimethate sodium developed to reduce treatment burden for people with cystic fibrosis. In our centre initial experience revealed 45% discontinued this therapy within 12 months, of which 83% were due to tolerance or device issues. Capsuleswere reformulated in 2017 to address some of these issues. We aimed to assess the prescription rates of Colobreathe® over 3 time periods to assess whether prescription practices and tolerance changed. Methods: A retrospective review of antibiotic challenges in the one-year periods from Dec 2013, 2016 and 2020 was conducted. Key end points included tolerance of test dose and continued use at 1 and 3 months. The proportion of antibiotic challenges that were Colobreathe® at each time point was compared. Results: Therewas a significant difference in the proportion of all antibiotic challenges whichwere for Colobreathe® across the 3 periods (2013–65/186 (35%), 2016–8/136 (6%), 2020–22/55 (40%), p < 0.001). The majority of patients at all 3 time points had previously nebulised colistimethate sodium (98%, 88% and 100%, respectively). All patients had a successful test dose during each time period. Therewas no difference in the proportion of patients who commenced long-term prescription following a 1-month review at the 3 time periods (75%, 75% and 73% respectively, p = 0.97). Of those who received a long-term prescription, continuation rates were similar at 3 months (82%, 100% and 93%, respectively). Conclusions: There was a marked reduction in inhaled antibiotic challenges in 2020, likely due to COVID. There was a significant change in prescription of Colobreathe® over the 3 time frames. Colobreathe®waswell tolerated at initial challenge and continuation rates after a month appear to be consistent. A number of factors likely influenced prescription practices, including early experience and potentially changing airway physiology following CFTR modulation introduction.

Microbiological surveillance in cystic fibrosis – an emerging multifactorial challenge

Objectives: Accurate identification of airway pathogens with appropriate eradication and suppressive therapies is associated with improved health outcomes in cystic fibrosis (CF). From 2020, 2 key factors may have influenced the ability to carry out this monitoring effectively;1. the COVID- 19 pandemic accelerated a transition to ‘virtual’ clinic visits and 2. the introduction of ELX/TEZ/IVA. Methods:We retrospectively analysed out-patient clinic attendance in the month of November for the years 2017–2021 and microbiological samples received from adults with CF in the regional microbiology department. Results: The total number of microbiological samples reduced in 2020 and 2021 (Table 1). In 2017, 211 samples were generated from 261 clinic visits (80.8%). For subsequent years this was 80.0%, 71.0%, 51.2% and 72.2%, respectively. The proportion of cough swabs significantly increased in 2021, (p < 0.001). In 20216 postal sampleswere provided, indicating that yield of a sample from a virtual appointment was at most 8.3%. Table 1. Overview of microbiological samples and clinic visits November 2017–2021 (Table Presented)Conclusions: There has been a marked reduction in microbiological samples in the years 2020 and 2021 despite relative preservation of total clinic appointments. This appears to be partly due to an increase in virtual clinic attendance without adequate remote sampling. The disproportionate increase in cough swabs in 2021 can be attributed to ELX/TEZ/IVA availability resulting in decreased sputum burden. This work identifies challenges in monitoring patients established on highly effective modulator therapy in new clinic models

Has the COVID-19 pandemic affected medication adherence to inhaled nebulised therapy for patients at a large adult cystic fibrosis centre?

Objectives: The COVID-19 pandemic has led to immense challenges for healthcare systems worldwide. People with cystic fibrosis (CF) were included in the clinically extremely vulnerable group for complications of coronavirus by the UK government and advised to shield during a national lockdown. Data suggests that pandemic-related restrictions have been linked to a reduction in pulmonary exacerbation events (PEx). We sought to explore whether an increase in medicine possession ratio and potentially adherence may be a factor in this finding. Methods: 50 patients who received medication through a homecare delivery system at a single large adult centre were randomly selected. Data from 12 months ‘pre-lockdown’ was compared to data for 9 months following start of shielding in March 2020. MPR was calculated and capped at 100%. Medications that were started or stopped during the pandemic were not included. Wilcoxon signed rank test was used to compare pre- and post-values. Results: 91 prescription medications were valid for analysis (45 nebulised antibiotics, 34 mucolytics and 12 CFTR modulators). MPR increased for 41 prescriptions (45.1%), decreased for 21 medications (23.1%) and remained unchanged for 29 medications (31.9%). Median MPR increased from 83% [57–100%] to 89% [66–100%], p = 0.037. MPR for nebulised antibiotics significantly increased (median 75% [54–100%] vs 89% [61–100%], p = 0.027). Median MPR for CFTR modulators was 100% throughout and did not change for mucolytics (75% [42–100%] vs 78% [53–100%], p = 0.419). Conclusion: We report a significant change in medication possession in adults with CF during the coronavirus pandemic in the UK. It is unclear whether this change translated to an increase in adherence but may be one factor in the reported decrease in PEx events described during this time. It is notable that increases were largely driven by inhaled antibiotics and this may represent a concerted effort to achieve maximal protection from infection.