P-019: Real-world treatment patterns, clinical outcomes, and healthcare resource utilization of individuals with light chain (AL) amyloidosis in Alberta, Canada: a population-based study

Background Amyloid light-chain (AL) amyloidosis is a rare disease with poor survival and significant morbidity. Limited information on the treatment patterns, healthcare resource utilization (HCRU) and clinical outcomes of Canadian AL amyloidosis patients is currently available. This study analyzed existing administrative claims data to better understand this patient population in the real-world setting. Methods Population-based administrative databases in Alberta, Canada were queried from 2010 to 2019 using a claims-based algorithm to identify potential cases of systemic AL amyloidosis. The medical charts of individuals flagged by the algorithm were subsequently reviewed by a trained clinician to confirm the diagnosis. Baseline characteristics, sequencing of pharmacologic therapies, overall survival (OS), and HCRU were evaluated. Individuals with AL amyloidosis were matched 1:4 with members of the general population based on age and sex. The mean difference in number of healthcare touch points was then estimated. HCRU was assessed starting from the time of diagnosis for individuals with AL amyloidosis and starting from the date of first encounter with the healthcare system within the corresponding calendar year for matched members of the general population. Robust variance estimation was used to address clustering due to matching. Results A total of 215 patients were confirmed to have AL amyloidosis. At baseline, the mean age at diagnosis was 66 years (range: 25 to 93 years). The majority of patients were men (59.5%), had an Eastern Cooperative Oncology Group (ECOG) performance status between 0-1 (60.9%), and had at least one comorbidity (84.7%). Approximately 1 in 3 patients had a concurrent multiple myeloma diagnosis. Renal and cardiac involvement were more common at baseline (67.9% and 55.8%, respectively) than liver involvement (15.3%). CyBorD was given to 66.4% of patients who initiated pharmacologic therapy, while most of the remaining 33.6% of patients received another bortezomib-based combination therapy. The most common 2L therapy was the combination of lenalidomide and dexamethasone which was given to 29.9% of individuals who initiated 2L. Median OS from initiation of 1L was markedly improved in patients diagnosed between 2012-2019 compared to 2010-2011 (63.4 vs. 34.5 months, respectively; log-rank p=0.07). Relative to age-sex matched members of the general population, individuals with AL amyloidosis had 118.7 more encounters with the healthcare system within the follow-up period (robust 95% CI: 79.4 to 157.9). Conclusions Since 2012, CyBorD has been the standard of care for Canadian AL amyloidosis patients. While survival has increased over time, 5-year survival remains low which highlights an unmet need for more effective therapies. Relative to the general population, individuals with AL amyloidosis had significantly higher HCRU, underscoring the high disease burden.