Patient-Reported Symptom Control of Diarrhea and Flushing in Patients with Neuroendocrine Tumors Treated with Lanreotide Depot/Autogel: Results from a Randomized, Placebo-Controlled, Double-Blind and 32-Week Open-Label Study.

Background: In the double-blind (DB) ELECT study, lanreotide depot/autogel significantly reduced versus placebo the need for short-acting octreotide for symptomatic carcinoid syndrome (CS) control in neuroendocrine tumor (NET) patients. Here we present patient-reported symptom data during DB and initial open-label (IOL) treatment.

Materials And Methods: Adults with NETs and CS history, with/without prior somatostatin analog use, were randomized to 16 weeks' DB lanreotide 120 mg subcutaneous or placebo every 4 weeks, followed by 32 weeks' IOL lanreotide. Patients recorded diarrhea and/or flushing frequency and severity daily by Interactive Voice (Web) Response System for 1 month prior to randomization and throughout the study.

Results: Of 115 patients randomized ( = 59 lanreotide,  = 56 placebo), 56 lanreotide and 45 placebo patients enrolled in the IOL phase. During DB treatment, least square (LS) mean percentages of days with moderate/severe diarrhea and/or flushing were significantly lower for lanreotide (23.4%) versus placebo (35.8%; LS mean difference [95% confidence interval]: -12.4 [-20.73 to -4.07];  = .004). For DB lanreotide patients, average daily composite (frequency × severity) diarrhea scores improved significantly between DB and IOL treatment (mean difference: -0.71 [-1.20 to -0.22];  = .005), and remained stable for diarrhea and/or flushing. For DB placebo patients, composite scores for diarrhea, flushing, and diarrhea and/or flushing improved significantly between DB and IOL treatment (mean differences: -1.07 [-1.65 to -0.49]; -1.06 [-1.93 to -0.19]; and -2.13 [-3.35 to -0.91]; all  ≤ .018).

Conclusion: Improved diarrhea and flushing control in CS patients during 16-week lanreotide treatment was sustained during maintenance of lanreotide treatment for the 32-week IOL phase (48 weeks total).

Implications For Practice: This study prospectively collected daily patient-reported data on diarrhea and flushing from the ELECT trial to evaluate the direct impact of lanreotide depot on patients' relief of carcinoid syndrome symptoms. Treatment with lanreotide depot was associated with significant reductions in the percentages of days patients reported symptoms of diarrhea and flushing, as well as reductions in the frequency and severity of daily symptoms compared with placebo during 16 weeks of double-blind treatment. These improvements were sustained for 32 additional weeks of open-label lanreotide treatment (i.e., through week 48 of treatment), resulting in clinically meaningful, long-term symptom reduction.