Prescribing InformationFor Patients

Functioning neuroendocrine tumors (fNETs) cause the overproduction of hormones1,2

Take control of the serotonin overproduction causing carcinoid syndrome diarrhea (CSD): combine XERMELO (telotristat ethyl) with SSA therapy in your adult patients with functioning neuroendocrine tumors (fNETs).3,4

The Serotonin Escape: Why SSAs alone may not be enough for patients with CSD3,5,6

Somatostatin analog (SSA) therapies alone may not adequately address serotonin overproduction and CSD. The majority of patients on SSA therapy require additional treatment to control their disease.5,6

SSA therapies bind to the surface of tumor cells, inhibiting the release of serotonin. Over time, various mechanisms of resistance can lead to a diminished response to SSA therapies, which can lead to serotonin escape.3,5,6

  • Over the 6-month octreotide clinical trial, approximately 50-70% of patients on octreotide required rescue injections to control exacerbation of carcinoid syndrome1,4
  • Symptom control disappears in about half of patients during the first year of SSA therapy3

Take a combination approach to combat the diminishing response to SSAs many patients experience over time3

Targets serotonin overproduction inside the cell3,4
SSA Therapy
Targets receptors outside the cell, to block the release of serotonin6
Combination therapy that works better together
Comprehensive control of carcinoid syndrome diarrhea7

Control the Tumor and the Hormones

For comprehensive control of functioning neuroendocrine tumors (fNETs), the tumors and the hormones should both be targeted.

XERMELO was developed through groundbreaking gene science technology and was evaluated in the largest clinical trial program for CSD5,7

See Clinical Trials Data

Learn how you can add XERMELO to SSA and use with any tumor control regimen for fNETs.


1. Appetecchia M, Baldelli R. Somatostatin analogues in the treatment of gastroenteropancreatic neuroendocrine tumours, current aspects and new perspectives. J Exp Clin Cancer Res. 2010;29:19.2. Pasieka JL, McKinnon JG, Kinnear S, et al. Carcinoid syndrome symposium on treatment modalities for gastrointestinal carcinoid tumours: symposium summary. Can J Surg. 2001;44:25-32.3. Molina-Cerrillo J, Alonso- Gordoa T, Martínez-Sáez O, Grande E. Inhibition of peripheral synthesis of serotonin as a new target in neuroendocrine tumors. Oncologist. 2016;21:701-707.4. XERMELO Prescribing Information. The Woodlands, TX: Lexicon Pharmaceuticals, Inc.; February 2017.5. Kulke MH, O’Dorisio T, Phan A, Merryman WD. Telotristat etiprate, a novel serotonin synthesis inhibitor, in patients with carcinoid syndrome and diarrhea not adequately controlled by octreotide. Endocr Relat Cancer. 2014;21:705-714.6. Sandostatin® LAR Depot Prescribing Information. East Hanover, NJ: Novartis Pharmaceuticals Corporation; 2019.7. Kulke MH, Hörsch D, Caplin ME, et al. Telotristat ethyl, a tryptophan hydroxylase inhibitor for the treatment of carcinoid syndrome. J Clin Oncol. 2017;35:14-23.8. Pavel M, Gross DJ, Benavent M, et al. Telotristat ethyl in carcinoid syndrome: safety and efficacy in the TELECAST phase 3 trial. Endocr Relat Cancer. 2018;25:309-322.

You may report an adverse event related to Lexicon products by calling 1-844-LEX-PHAR (1-844-539-7427) (US only). If you prefer, you may contact the US Food and Drug Administration (FDA) directly. The FDA has established a reporting service known as MedWatch where healthcare professionals and consumers can report serious problems they suspect may be associated with the drugs and medical devices they prescribe, dispense, or use. Visit MedWatch or call 1-800-FDA-1088.

Copyright © 2019 Lexicon Pharmaceuticals, Inc. All rights reserved.
December 2019 PP-XER-US-0053

Important Safety Information and Indication

Important Safety Information

For more information about XERMELO see Full Prescribing Information

  • Warnings and Precautions: XERMELO may cause constipation, which can be serious. Monitor for signs and symptoms of constipation and/or severe, persistent, or worsening abdominal pain in patients taking XERMELO. Discontinue XERMELO if severe constipation or severe, persistent, or worsening abdominal pain develops.
  • Adverse Reactions: The most common adverse reactions (≥5%) include nausea, headache, increased gammaglutamyl-transferase, depression, flatulence, decreased appetite, peripheral edema, and pyrexia.
  • Drug Interactions: If necessary, consider increasing the dose of concomitant CYP3A4 substrates, as XERMELO may decrease their systemic exposure. If combination treatment with XERMELO and short-acting octreotide is needed, administer short-acting octreotide at least 30 minutes after administering XERMELO.


  • XERMELO is a tryptophan hydroxylase inhibitor indicated for the treatment of carcinoid syndrome diarrhea in combination with somatostatin analog (SSA) therapy in adults inadequately controlled by SSA therapy.

For more information about XERMELO see Full Prescribing Information