Projecting the impact of delayed access to elexacaftor/tezacaftor/ivacaftor for people with Cystic Fibrosis.

BACKGROUND: Therapies that target the underlying defect in Cystic Fibrosis (CF) will likely impact the future characteristics of the CF population and healthcare utilization. The objectives of this study were to estimate the potential impact of elexacaftor/tezacaftor/ivacaftor on morbidity and mortality, and the impact of delayed access. METHOD: A microsimulation transition model was applied to Canadian CF Registry data to forecast lung disease severity, pulmonary exacerbations, deaths and transplants to 2030 under three scenarios: 1) no availability of elexacaftor/tezacaftor/ivacaftor, 2) availability in 2021 ('early') or 3) availability in 2025 ('delayed'). Published Phase III data on treatment effects were used to estimate transition rates between disease severity states. RESULTS: Under specific assumptions regarding disease state and treatment effect applied to the Canadian CF population it is projected that by 2030, early introduction of elexacaftor/tezacaftor/ivacaftor is expected to reduce the number of individuals with severe lung disease by 60% (95% CI 55.3; 63.9), increase the number of individuals with mild lung disease by 18% (95%CI 18.2; 19.0) and reduce the number of pulmonary exacerbations by 19% (95%CI 18.9; 19.5). Earlier introduction of elexacaftor/tezacaftor/ivacaftor could reduce deaths by 15% (95% 13.2; 18.4) and improve the median age of survival by 9.2 years (7.5; 10.8) over a 10-year period. The expected benefits of therapy are cumulative, therefore delayed access to elexacaftor/tezacaftor/ivacaftor will result in preventable health care utilization and deaths. CONCLUSIONS: Delayed access to elexacaftor/tezacaftor/ivacaftor will have a negative impact on lung health and survival in the CF population.

Are N-of-1 trials an economically viable option to improve access to selected high cost medications? The Australian experience.

OBJECTIVE: To explore the economic viability of N-of-1 trials for improving access to selected high cost medications in Australia. METHODS: Cost and effectiveness estimates were derived from two N-of-1 trials conducted by The University of Queensland from 2003 to 2005-celecoxib versus sustained-release paracetamol for osteoarthritis in a general practice setting and gabapentin versus placebo for chronic neuropathic pain in a hospital setting. Effectiveness was determined by the proportion of responders to each medication. The costs of trials were offset against the savings generated by subsequent changes in prescribing. Decision analysis models with semi-Markov processes were used to compare different scenarios of N-of-1 trials versus usual care. RESULTS: The fixed cost of performing N-of-1 trials was approximately AUS$23,000 for each trial and the variable cost was approximately AUS$1300 per participant. Clinical outcomes favored celecoxib over paracetamol in 17% of participants and gabapentin over placebo in 24% of participants. Modeling these results showed that the cost-offsets from efficient use of medications were less than the cost of running a trial; however, the incremental costs per quality-adjusted life-year gained were AUS$6,896 and AUS$29,550 for the gabapentin/placebo and celecoxib/paracetamol trials, respectively, over a 5-year horizon. Key factors affecting the viability were the time horizon modeled, the variable cost per participant, the probability of response to the intervention medication, and rates of use in nonresponders and the usual care alternative. CONCLUSIONS: The N-of-1 strategy offers a realistic and viable option for increasing access to selected high cost medications where the medications are used for the symptomatic treatment of chronic disease, have rapid onset of action, and clinical response is unpredictable without a trial.