RESUMO
BACKGROUND: When carcinoid syndrome (CS) diarrhea (CSD) is inadequately controlled with long-acting somatostatin analogs (SSAs), clinical practice guidelines recommend addition of the tryptophan hydroxylase inhibitor telotristat ethyl (TE). In a 12-week multinational, randomized controlled trial, TE added to SSA reduced peripheral serotonin and the frequency of CSD. We evaluated real-world effectiveness of TE using patient-reported data from a nurse support program over 3 months. MATERIALS AND METHODS: This study used a deidentified data set of patients initiating TE who opted into a nurse support program between March and November 2017 and reported CS symptom burden at baseline and at least one follow-up time point at months 1, 2, and 3. Patients reported demographic and medical history information as well as frequency of bowel movements (BMs) and flushing episodes, severity of nausea, urgency and abdominal pain (0 "no/not at all" to 100 "worst imaginable/very urgent"), and stool form (1 "very hard" to 10 "watery"). Mean changes from baseline in CS symptom burden were reported using paired-sample t tests and Wilcoxon signed-rank tests. RESULTS: Most patients initiating TE enrolled in the nurse program (791/898, 88%), of whom 369 (47%) were included in the analysis. Patients treated with TE reported significant reductions in CSD and other CS symptoms (all p < .001). At least half of patients treated with TE experienced ≥30% improvement from baseline in BM frequency and an average reduction of at least two BMs per day within 3 months. CONCLUSION: Patients taking SSA therapy showed substantial burden of disease before initiating TE and significant improvements with the addition of TE treatment in this real-world effectiveness study. IMPLICATIONS FOR PRACTICE: Patients with carcinoid syndrome diarrhea uncontrolled by high doses of long-acting somatostatin analogs may be candidates for additional therapy with the tryptophan hydroxylase inhibitor telotristat ethyl. Understanding the real-world prevalence of uncontrolled symptoms and the effectiveness of telotristat ethyl in clinical practice may further support clinical and policy decisions for these patients. This study investigated self-reported carcinoid syndrome symptom burden and improvements among patients initiating telotristat ethyl and participating in a voluntary nurse support program. Disease burden and off-label somatostatin analog treatment before initiating telotristat ethyl were high, and symptoms improved markedly over 1, 2, and 3 months of treatment.