SUN-LB079 Acrostudy - Safety And Treatment Outcomes In 2221 Patients With Acromegaly Treated With Pegvisomant: Real World Experience

ACROSTUDY is an open-label, non-interventional post-authorization safety study (PASS) that began in 2004 to evaluate safety in at least 1000 acromegaly patients treated for 5 years with the GH receptor antagonist pegvisomant (PEGV). &nbsp;This commitment was fulfilled in 2013 but ACROSTUDY was extended as a voluntary PASS, ultimately collecting data on 2221 patients who were followed through Dec 2017. Objectives: &nbsp;To monitor the long-term safety of PEGV including the pituitary tumor volume, as prescribed in clinical practice. Patients & Methods: 50.8% were male, 92.4% Caucasian with median age 41.1 years (1.7-83.7) at diagnosis and median age 49.7 years (3.9-85.6) at start of PEGV. Mean duration of PEGV treatment was 9.3 years (0.0-20.8); 80.8% of patients started PEGV on a daily schedule and patients came from fifteen countries. Safety data included adverse events, change in tumor volume and liver tests. &nbsp;Efficacy was measured by IGF-I control (Patients were considered ‘IGF-I Controlled’ if the most temporally-related IGF-I measurement was normal for the local reference laboratory). Patient-reported outcomes (PROs) were evaluated using the PatientAssessed Acromegaly Symptom Questionnaire (PASQ). Results: &nbsp;No new safety signals were identified in the study. &nbsp;IGF-I SDS >2 decreased progressively from 88.4% of patients at baseline to 34.8% at year 5 at a mean dose(±SD) of 19.2(±12.9) mg/day; 63.3% of patients with a documented normal IGF-I SDS had a mean dose of 16.2(±9.03), while 1.9% had IGF-I SDS < -2 at a mean dose of 16.5(±5.81). 1795 Patients had at least 1 local pituitary imaging result reported: 71.1% of patients reported no change, 17.3% reported a decrease and 7.1% reported an increase in tumor size while 4.5% reported both an increase and a decrease. Scans reported as showing a meaningful change in tumor volume (n=264) were re-evaluated centrally by an independent expert: 54 were corroborated enlarged, 84 were decreased, 12 were read as both increased and decreased, 23 were read as no change and 40 inconclusive; thus the overall incidence of (corroborated) tumor increases was 3.0% and decreases 4.7%. In the overall cohort, AST and/or ALT were >3 × ULN at any time during PEGV treatment in 3.2% of patients. PASQ score was 15 (0-46) at baseline and 10 (0-41) at year 8. Summary: &nbsp;In this real world international study, overall biochemical control (i.e. normal IGF-I) progressively improved with pegvisomant, and was achieved in 63.3% patients by year 5. Improved IGF-I control was associated with improved symptoms of acromegaly. Importantly, in this large cohort of patients the incidence of pituitary tumor increase and liver test elevations were low, and similar to previously reported rates. One limitation of this observational study was that the PEGV dose may not have been adequately titrated to achieve IGF-I normalization. Unless otherwise noted, all abstracts presented at ENDO are embargoed until the date and time of presentation. For oral presentations, the abstracts are embargoed until the session begins. Abstracts presented at a news conference are embargoed until the date and time of the news conference. The Endocrine Society reserves the right to lift the embargo on specific abstracts that are selected for promotion prior to or during ENDO.