We sought to demonstrate a first-of-its-kind successful linkage of real-world Medicare claims data from the Centers for Medicare & Medicaid Services to data from the GRADUATE I and II phase III clinical trials of gantenerumab, and to understand differences in healthcare resource utilization (HCRU) in participants with early symptomatic AD.

The detailed clinical and patient-reported outcomes data typically collected in clinical trials are often missing a broader, more holistic understanding of HCRU and costs, particularly before and after the clinical trial.

AD-LINE is a non-interventional cohort study of Medicare patients with early symptomatic AD who were enrolled in the GRADUATE pivotal trials. Participants consented to combine existing (including year preceding GRADUATE entry) and future medical claims with clinical trial data. HCRU was examined for the year preceding their baseline trial visit.

In total, 111 GRADUATE participants were included in AD-LINE. Mean age was 75.1 years (SD: 5.5); 67 participants (60.4%) were female. At baseline, 55 participants (49.5%) had MCI-AD and 56 (50.5%) had mild AD dementia.

This early proof-of-concept linkage analysis includes data from the GRADUATE baseline visit and Medicare claims through December 2019 (latest currently available). Excluding 2020 clinical trial entrants, there were 79 patients; of those, 78 were continuously enrolled in Medicare Parts A/B and 46 were not in a health maintenance organization (HMO) in the preceding year. Sample size and data availability will increase as more Medicare claims and GRADUATE study data become available. Initial results show that in the year preceding GRADUATE trial entry, these 46 AD-LINE patients had an average of 4.09 outpatient visits.

AD-LINE is the first study to successfully link large phase III clinical trial and real-world claims data. Linking trial data with HCRU data may provide critical information for payers and population health decision makers.