FDA New Drug and Biologic Approvals -- 2017 Year-in-Review

Mary L Windle, PharmD


January 11, 2018

In This Article

Xermelo (telotristat ethyl)


Treatment of carcinoid syndrome diarrhea in combination with somatostatin analog (SSA) therapy in adults inadequately controlled by SSA therapy alone.


Telotristat, the active metabolite of telotristat ethyl, inhibits tryptophan hydroxylase, which mediates the rate limiting step in serotonin biosynthesis. Serotonin plays a role in mediating secretion, motility, inflammation, and sensation of the GI tract, and is overproduced in patients with carcinoid syndrome.


250 mg PO TID. Discontinue if severe constipation develops.


Approval was based on a 12-week, double-blind, placebo-controlled trial (n=135). These patients were experiencing 4 or more bowel movements per day despite the use of an SSA. In the trial, all patients remained on their SSA treatment and were randomly assigned to add placebo or telotristat 3 times daily. Bowel movement frequency reduction ≥30% from baseline for ≥50% of the double-blind treatment period was observed in 20%, 44%, and 42% of patients given placebo, telotristat ethyl 250 mg, and telotristat ethyl 500 mg, respectively. The FDA approved the 250 mg TID dosage regimen.


Kulke MH, et al. Telotristat Ethyl, a Tryptophan Hydroxylase Inhibitor for the Treatment of Carcinoid Syndrome. J Clin Oncol. 2017 Jan;35(1):14-23.


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