Tumor shrinkage with lanreotide Autogel 120 mg as primary therapy in acromegaly: results of a prospective multicenter clinical trial.

CONTEXT

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.

OBJECTIVE

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.

DESIGN

PRIMARYS was a 48-week, multicenter, open-label, single-arm study.

SETTING

The study was conducted at specialist endocrine centers.

PATIENTS

Treatment-naïve acromegalic patients with GH-secreting macroadenomas participated in the study.

INTERVENTION

Lanreotide Autogel 120 mg was administered sc every 28 days (without dose titration).

OUTCOME MEASURES

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 (H0) 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.

RESULTS

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; H0 not rejected) and 71.9-75.3% in sensitivity (n = 89) and secondary analyses (n = 63) (H0 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.

CONCLUSIONS

Primary treatment with lanreotide Autogel, administered at 120 mg (highest available dose) without dose titration, in patients with GH-secreting macroadenomas provides early and sustained reductions in tumor volume, GH and IGF-1, and acromegalic symptoms, and improves QoL.