ISSN 1470-3947 (print) | ISSN 1479-6848 (online)

Endocrine Abstracts (2019) 63 GP58 | DOI: 10.1530/endoabs.63.GP58

ACROSTUDY - safety and efficacy in a cohort of 110 Naive patients with acromegaly treated with pegvisomant

Michael Wajnrajch1,2, Roy Gomez3, Judith Hey-Hadavi1, Nikoletta Kelepouris4, Joli van der Lans5, Jane Loftus6, Cecilia Camacho-Hubner1, Maria Fleseriu7, Roberto Salvatori8, Jose Cara1 & Andrew Palladino4

1Pfizer Inc, New York, New York, USA; 2NYU School of Medicine, New York, New York, USA; 3Pfizer, Brussels, Belgium; 4Pfizer Inc, Collegeville, Pennsylvania, USA; 5Pfizer, Amsterdam, Netherlands; 6Pfizer Ltd, Sandwhich, UK; 7Oregon Health Sciences University, Portland, Oregon, USA; 8Johns Hopkins Medical Institute, Baltimore, Maryland, USA.

Background: ACROSTUDY is an open-label, non-interventional post-authorization safety study that began in 2004 to evaluate safety in at least 1000 acromegaly patients treated with the GH receptor antagonist pegvisomant (PEGV). This commitment was fulfilled in Jan 2013. ACROSTUDY was later amended to enroll an additional 110 patients that were naïve/semi-naive to PEGV treatment. Semi-naïve patients are defined as not having received PEGV therapy for at least 6 months prior to enrollment.

Objectives: The primary objectives were to: i) assess the long-term safety of PEGV in real world practice; ii) assess the effect of IGF-I normalization on treatment outcomes, including safety, glucose control and patient-reported outcomes (PROs).

Patients & Methods: 110 patients with Acromegaly 53.6% male, 81.8% Caucasian, median age 42.4 years at diagnosis; median age 48.9 years at PEGV start. Patients were considered ‘IGF-I Controlled’ if the most temporally-related IGF-I measurement was normal for that laboratory. Safety data including adverse events and liver tests were collected. IGF-I and HbA1c were measured; PROs were evaluated using the Acromegaly Quality of Life Questionnaire (AcroQoL) and Patient-Assessed Acromegaly Symptom Questionnaire (PAQ19), stratified by IGF-I control.

Results: No new safety signals were identified in this sub-study. IGF-I SDS >2 decreased from 87% of patients at baseline to 31% at year 2 at a mean dose (±S.D.) of 10.4 (±7.45) mg/day; patients with IGF-I SDS <2 had a mean dose of 14.8(±6.7). Among IGF-I controlled patients, median (range) HbA1c levels were 5.8% (5.4–6.1) at baseline and 5.6% (4.5–7.2) at year 2; in IGF-I uncontrolled patients, HbA1c was 6.1% (4.9–6.6) at baseline and 6.3% (2.9–10.6) at year 2. Among IGF-I controlled patients, median (range) global AcroQoL scores were 54.6 (24–73) at baseline and 61.4 (13–86) at year 2; while in IGF-I uncontrolled patients, median global AcroQoL score was 59.7 (8–92) at baseline and 63.6 (25–76) at year 2. Among IGF-I controlled patients, median (range) total PAQ19 score was 20 (3–38) at baseline and 17.5 (1–40) at year 2; in IGF-I uncontrolled patients, median total PAQ19 score was 17 (0–44) at baseline and 14 (3–39) at year 2.

Summary: In this real-life world international study, overall biochemical control (i.e. normal IGF-I) was achieved with pegvisomant in 64.3% patients by year 2. Improved IGF-I control was associated with improved HbA1c, QoL and symptoms of acromegaly. One limitation of the study was that the PEGV dose may not have been sufficiently titrated to achieve IGF-I normalization.