Lexicon Pharmaceuticals, Inc., is currently conducting a Phase 2, multicenter, open-label, 2-stage study to assess the safety, tolerability, and efficacy of telotristat ethyl in combination with first-line (1L) therapy (cisplatin [cis] plus gemcitabine [gem]) in patients with unresectable, locally advanced, recurrent or metastatic biliary tract cancer (intrahepatic or extrahepatic cholangiocarcinoma, gallbladder cancer), who are naïve to tumor-directed therapy in the locally advanced or metastatic setting, and for which treatment with 1L therapy (defined as a combination of cis/gem) is planned. Details about this study can be found at clinicaltrials.gov ID: NCT03790111.

Primary Objectives:

  • The purpose of this study is to test whether telotristat ethyl, when given with chemotherapy (cis/gem) that is used as a standard treatment, will have an effect on the growth of BTC tumor(s) and progression-free survival rate at 6 months
  • Safety of using these drugs in combination will also be evaluated

Qualification criteria include:

  • Must be at least 18 years old
  • Must have confirmation of unresectable, locally advance, recurrent, or metastatic BTC
  • Must have plans to initiate cis/gem treatment as standard of care
  • Cannot have prior exposure to telotristat ethyl, telotristat etiprate, LX1032, or LX1606
  • Cannot have primary tumor in ampulla of Vater


  • Screening Period – up to 42 days
  • Treatment Period – approximately 6 months
  • Follow-up Period – up to 24 months


  • Telotristat ethyl 500 mg tid, plus
  • Cisplatin 25 mg/m2 iv, plus
  • Gemcitabine 1000 mg/m2 iv
    Administered on Day 1 and Day 8 of 21-day cycles