Coadministration of lanreotide Autogel and pegvisomant normalizes IGF1 levels and is well tolerated in patients with acromegaly partially controlled by somatostatin analogs alone

Abstract

ObjectiveTo evaluate the efficacy and safety of coadministered lanreotide Autogel (LA; 120 mg/month) and pegvisomant (40–120 mg/week) in acromegaly.DesignThis is a 28-week, multicenter, open-label, single-arm sequential study.MethodsPatients (n=92) biochemically uncontrolled, on somatostatin analogs (SSAs) or using pegvisomant monotherapy entered a 4-month run-in taking LA (120 mg/month). Patients uncontrolled after the run-in period (n=57) entered a 28-week coadministration period, receiving LA 120 mg/month plus pegvisomant (60 mg once weekly, adapted every 8 weeks based on IGF1 levels to 40–80 mg once weekly or 40 or 60 mg twice weekly).ResultsIn total, 33 (57.9%) patients had normalized IGF1 following coadministration (P<0.0001 versus 30% minimum clinically relevant); median pegvisomant dose in normalized patients was 60 mg/week. IGF1 normalized at any time during coadministration in 45 (78.9%) patients (P<0.0001) with median pegvisomant dose at 60 mg/week. Being nondiabetic (odds ratio (OR): 4.65) and older (OR, upper versus lower quartile: 3.40) showed increased likelihood of normalization. Symptom reduction was greatest for arthralgia (−0.6±1.6) and soft tissue swelling (−0.6±1.8). Five patients reported treatment-emergent adverse events causing treatment withdrawal: three serious (treatment related – thrombocytopenia, urticaria; not treatment related – abdominal pain/vomiting) and two nonserious (hepatotoxicity and cytolytic hepatitis, both elevating alanine aminotransferase to >5×upper limit of normal with normalization after withdrawal).ConclusionsIn patients partially controlled by SSAs, LA (120 mg/month) plus pegvisomant normalized IGF1 in 57.9% of patients after 7 months, at a median effective pegvisomant dose of 60 mg/week, and 78.9% at any time. In these patients, results suggest a pegvisomant-sparing effect versus daily pegvisomant monotherapy.