Treatment Patterns and Clinical Outcomes of Patients With Systemic Light Chain Amyloidosis in the United States: Evidence From Real-World Clinical Practice.

Background: This study described real-world treatment patterns and outcomes in patients with systemic light chain (AL) amyloidosis in the United States (US).

Methods: De-identified chart review data were obtained from 117 adult patients diagnosed with systemic AL amyloidosis (01/01/2014-12/31/2021) who initiated 1 L treatment, outside of a clinical trial setting, on or after January 1, 2014, and received ≥ 1 treatment at a US medical center.

Results: Among patients, (median age: 63.2 years; female: 50.4%; White: 73.5%; Black/African American: 14.5%), most patients received 2 or more lines of treatment (62.4%) with 30.8% receiving 2 lines of treatment, predominantly cyclophosphamide, bortezomib, and dexamethasone (CyBorD)-, daratumumab-, and dexamethasone-based regimens. In first-line, one third of patients had hematologic response (complete response [CR]: 31.6%; very good partial response (29.1%); for later lines, CR rates tended to decrease. By 57.5 months, ≥60% of patients were still alive (Kaplan-Meier rates - 12 months: 92.0%; 24 months: 84.4%). Median progression-free survival (41.4 months), event-free survival (24.4 months), and time to next treatment (43.2 months) were unexpectedly longest in second line.

Conclusions: The study demonstrated that there was heterogeneity in the treatment of AL amyloidosis, and patients who receive treatment can survive for several years after diagnosis without progression.