Changes in Carcinoid Syndrome Symptoms Among Patients Receiving Telotristat Ethyl in US Clinical Practice: Findings from the TELEPRO-II Real-World Study.

Background: Inadequately controlled symptoms incur a substantial burden on patients with neuroendocrine tumors and carcinoid syndrome (CS). The effectiveness of telotristat ethyl (TE) with a somatostatin analog for uncontrolled CS diarrhea has been demonstrated in clinical trials and observational studies. TELEPRO-II was a prospective observational study evaluating TE's effectiveness in clinical practice over the first 3 months of treatment.

Methods: Patients initiating TE in 2018 participated in an optional nurse support program reporting CS symptoms during interviews at baseline and 1, 2, and 3 months after TE initiation. Eligible patients received TE for ≥3 months and reported symptom burden at baseline and ≥1 follow-up visit within the first 3 months. Daily bowel movement (BM) frequency and flushing episodes were reported as events/episodes per day. Stool consistency, nausea severity, urgency severity, and abdominal pain were reported on a severity scale (1-10). Symptom changes were evaluated using paired-sample -tests and Wilcoxon signed-rank tests. Analysis of symptoms based on achievement of <30% or ≥30% reduction in daily BM frequency was conducted using a cumulative distribution function.

Results: A total of 684/1603 (43%) patients were eligible for analysis. At baseline, patients reported a mean of 6.3 BM/day, nausea severity of 8.4/10 and stool urgency of 8.2/10. Significant improvements in all CS symptoms were observed after 3 months of TE. Mean daily BMs were reduced 64% after 3 months of TE (mean reduction [SD], -3.99 [3.8]; P<0.0001). Most patients (74%, n=503) reported ≥30% reduction in daily BM frequency; these patients also reported improvements in other symptoms (76-87%). Patients with <30% reduction in daily BMs also reported improvements in nausea severity (62%, n=24), daily flushing episodes (66%, n=98), abdominal pain (50%, n=60), urgency severity (38%, n=64), and stool consistency (24%, n=44).

Conclusion: Patients treated with TE in a real-world setting experienced significant, clinically meaningful improvements in CS symptoms.