Methodological shortcomings often compromise investigations into the effects of primary somatostatin-analog treatment on tumor size in acromegaly. There are also limited data for the long-acting lanreotide formulation.
The aim of the study was to better characterize the effects of primary lanreotide Autogel treatment on tumor size in patients with GH-secreting macroadenomas.
Treatment-naïve acromegalic patients with GH-secreting macroadenomas participated in the study.
The primary endpoint was the proportion of patients with clinically significant (≥20%) tumor volume reduction (TVR) at week 48/last post-baseline value available using central assessments from three readers. The null hypothesis ( H 0) for the primary endpoint was that the proportion with TVR was ≤55%. Secondary endpoints included: TVR at other time points, GH and IGF-1, acromegalic symptoms, quality of life (QoL), and safety.
Sixty-four of 90 (71.1%) patients completed the study. Clinically significant TVR at 48 weeks/last post-baseline value available was achieved by 62.9% (95% confidence interval, 52.0, 72.9) of 89 patients in the primary analysis (intention-to-treat population; H 0 not rejected) and 71.9–75.3% in sensitivity (n = 89) and secondary analyses (n = 63) ( H 0 rejected). At 12 weeks, 54.1% had clinically significant TVR. Early and sustained improvements also occurred in GH and IGF-1, acromegalic symptoms, and QoL. No patients withdrew due to gastrointestinal intolerance.