SUN-024 - Somatostatin Receptor Ligand Adherence and Time to IGF-1 Control in Acromegaly: US Real-World Evidence from Linked Claims and EHR Data

Introduction:
Claims-based real-world evidence in acromegaly historically lacks biochemical lab data, limiting assessment of treatment effectiveness. We used US claims linked to EHR laboratory data to test whether adherence to somatostatin receptor ligands (SRLs) is associated with insulin-like growth factor-1 (IGF-1) normalization.

Methods:
Retrospective cohort study using Optum Market Clarity claims linked to EHR labs (01/01/2016–09/30/2024). Adults with acromegaly initiating an SRL (index = first SRL claim) required ≥6 months continuous enrollment pre-index and ≥1 post-index IGF-1 result. Adherence was assessed by proportion of days covered (PDC), defined as the percentage of days with medication on hand, and categorized as high (≥0.8) or low ( < 0.8). IGF-1 control was age- and sex-adjusted within-lab reference range. Follow-up ended at first control, disenrollment, or end of observation. Time to first control was summarized using Kaplan–Meier and compared by log-rank test.

Results:
Of 8,430 adults with acromegaly, 1,857 initiated SRLs and 156 met eligibility. At baseline, mean age was 51.1 years (SD 14.2); 53.9% were female. Common comorbidities included hypertension (42.3%), diabetes without complication (39.1%), sleep apnea (29.5%), esophageal reflux (18.6%), and osteoarthritis (14.7%). Medication burden was substantial (mean 6.53 unique classes; median 6 [IQR 3–10]). Frequent classes included opiate agonists (25.6%), adrenal agents (25.0%), thyroid agents (25.0%), statins (23.7%), proton-pump inhibitors (19.2%), dopamine agonists (19.2%), beta-blockers (18.0%), antibiotics (16.0%), ACE inhibitors (14.7%), and antidiabetic medications (13.5%).

Among 156 patients, 107 (68.6%) were high-adherent and 49 (31.4%) low-adherent. Overall Kaplan–Meier cumulative IGF-1 control was 20.5% (25 of 123 at risk) at 3 months, 29.0% (31 of 107) at 6 months, 42.0% (35 of 84) at 12 months, and 53.4% (33 of 62) at 24 months. Control rates differed significantly by adherence. Curves separated early and remained distinct: 30.0% (22 of 74) vs. 0.0% (0 of 49) at 3 months, 40.6% (25 of 61) vs. 4.1% (2 of 46) at 6 months, 52.8% (24 of 45) vs. 18.7% (7 of 39) at 12 months, and 66.0% (20 of 30) vs. 27.1% (9 of 32) at 24 months (absolute difference 38.9 percentage points; log-rank p < 0.001).

Conclusion:
Linking claims with EHR labs provides a novel real-world approach to evaluating adherence and biochemical response in acromegaly. Patients had high comorbidity and medication burden. Higher SRL adherence was strongly associated with faster and greater likelihood of IGF-1 normalization through 24 months, underscoring the importance of adherence-focused strategies and treatment options that reduce burden. Notably, only 42% of patients achieved biochemical control at 12 months, highlighting the need to improve adherence and optimize overall management.

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