A Phase 2 interventional study of Carbon C 11 Alpha-methyltryptophan and Laboratory Biomarker Analysis in Carcinoid Syndrome and Metastatic Nonfunctional Well Differentiated Neuroendocrine Neoplasm, sponsored by Barbara Ann Karmanos Cancer Institute. Completed at 1 site in United States. Open to participants aged 18 Years and older. Per ClinicalTrials.gov, last updated 2025-04-10.
Sponsored by Barbara Ann Karmanos Cancer Institute · Phase 2, Interventional, and Treatment
This pilot trial studies how well telotristat etiprate works in treating participants with well differentiated neuroendocrine neoplasm that has spread to other places in the body and monitored by carbon C 11 alpha-methyltryptophan (AMT)-emission tomography (PET). Telotristat etiprate may stop the growth of tumor cells by blocking some of the enzymes needed for cell growth. Studying the changes within the tumor cells via AMT-PET may help doctors better understand how tumors respond to treatment with telotristat etiprate.
PRIMARY OBJECTIVES:
I. To evaluate the effect of telotristat etiprate (telotristat ethyl) treatment in patients with advanced neuroendocrine tumors (NETs) using carbon C 11 alpha-methyltryptophan (alpha-[11C]methyl-?L-?tryptophan) (AMT)-?positron emission tomography (PET) as measured by changes in tumor maximum standardized uptake value (SUVmax).
SECONDARY OBJECTIVES:
I. Show that NETs will have increased AMT uptake on PET, as compared to surrounding non-tumor tissue at baseline.
II. Use compartmental modeling (in tumors with the left ventricle of the heart in the field-of-view) to measure change in AMT retention.
III. Measure change in AMT retention as mean standardized uptake value (SUVmean).
OUTLINE:
Participants undergo AMT-PET within 7 days prior to, and 9-14 days after start of telotristat etiprate treatment. Participants receive telotristat etiprate orally (PO) three times a day (TID) for 9-14 days.
After completion of study treatment, participants are followed up for 3 months.
35 studies on the registry are indexed under Serotonin Syndrome; 1 is open to participants now.
This study's enrollment of 4 is below the median of 20 across 23 interventional studies indexed under Serotonin Syndrome.
Browse Serotonin Syndrome studies →Barbara Ann Karmanos Cancer Institute is the lead sponsor of 161 studies on the registry; 19 are open to participants now.
Of its 8 completed or terminated interventional studies of FDA-regulated products, 6 (75%) have results posted.
Counted across the registry records on this site, refreshed daily.
Go through the criteria one by one — yes, no or not sure — and take the list to your doctor or the study team. Kept in this browser only.
Exclusion Criteria:
Underlined terms in the criteria open these too. Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Cancer that has spread from where it began to other parts of the body. “Metastatic” cancer is cancer that has spread this way.
The top of the normal range for a blood test, as set by the laboratory that runs it. Each lab prints its own range next to your result.
“≤ 2.5 × ULN” means the result can be up to two and a half times that top value.
A scale of how much an illness limits everyday activity. For people being assessed to join a study, scores run from 0 (fully active) to 4; lower is more active.
Studies most often ask for 0–1 or 0–2. Your doctor gives the score; the WHO scale uses the same steps. The full scale also has 5, which records death.
A yellow substance made when red blood cells are broken down, which the liver clears. A high level can mean a problem with the liver or the bile ducts.
Criteria often allow more for people with Gilbert’s syndrome, a harmless inherited condition that raises bilirubin.
Two enzymes measured in a routine blood test of the liver. Higher levels can mean the liver is under strain or damaged. SGPT and SGOT are older names for ALT and AST.
Criteria usually give a limit as a multiple of the upper limit of normal (ULN), often higher when cancer has spread to the liver.
Able to have children. For women this usually means from the first period until menopause, unless permanently unable to through surgery; for men, unless permanently sterile. Read who the line is about — participants, women, men, or their partners.
Criteria about it usually ask for contraception during the study and for a time after it.
Ways of preventing pregnancy. “Highly effective” methods fail less than 1% of the time a year when used correctly — for example an IUD or an implant.
Criteria usually say which methods count and how long to keep using them after the last dose, sometimes for male participants too. Some studies accept a partner’s vasectomy if it was confirmed successful and that person is the participant’s only sexual partner.
Metastases
Cancer that has spread from where it began to other parts of the body. “Metastatic” cancer is cancer that has spread this way.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
ULN (upper limit of normal)
The top of the normal range for a blood test, as set by the laboratory that runs it. Each lab prints its own range next to your result.
“≤ 2.5 × ULN” means the result can be up to two and a half times that top value.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
ECOG performance status
A scale of how much an illness limits everyday activity. For people being assessed to join a study, scores run from 0 (fully active) to 4; lower is more active.
Studies most often ask for 0–1 or 0–2. Your doctor gives the score; the WHO scale uses the same steps. The full scale also has 5, which records death.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Bilirubin
A yellow substance made when red blood cells are broken down, which the liver clears. A high level can mean a problem with the liver or the bile ducts.
Criteria often allow more for people with Gilbert’s syndrome, a harmless inherited condition that raises bilirubin.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
ALT and AST (liver enzymes)
Two enzymes measured in a routine blood test of the liver. Higher levels can mean the liver is under strain or damaged. SGPT and SGOT are older names for ALT and AST.
Criteria usually give a limit as a multiple of the upper limit of normal (ULN), often higher when cancer has spread to the liver.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Reproductive potential
Able to have children. For women this usually means from the first period until menopause, unless permanently unable to through surgery; for men, unless permanently sterile. Read who the line is about — participants, women, men, or their partners.
Criteria about it usually ask for contraception during the study and for a time after it.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Contraception
Ways of preventing pregnancy. “Highly effective” methods fail less than 1% of the time a year when used correctly — for example an IUD or an implant.
Criteria usually say which methods count and how long to keep using them after the last dose, sometimes for male participants too. Some studies accept a partner’s vasectomy if it was confirmed successful and that person is the participant’s only sexual partner.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Participants undergo AMT-PET within 7 days prior to, and 9-14 days after start of telotristat etiprate treatment. Participants receive telotristat etiprate PO TID for 9-14 days.
Other: Carbon C 11 Alpha-methyltryptophan · Other: Laboratory Biomarker Analysis · Procedure: Positron Emission Tomography · Drug: Telotristat Etiprate
Undergo AMT-PET
Also known as: 11C-alpha-methyltryptophan, 11C-AMT, [11C] AMT, alpha-[11C]methyl-L-tryptophan
Correlative studies
Undergo AMT-PET
Also known as: Medical Imaging, Positron Emission Tomography, PET, PET Scan, Positron Emission Tomography Scan, Positron-Emission Tomography, proton magnetic resonance spectroscopic imaging
Given PO
Also known as: LX1032 Hippurate, LX1606, LX1606 Hippurate, TPH Inhibitor LX1606, Tryptophan Hydroxylase Inhibitor LX1032, Tryptophan Hydroxylase Inhibitor LX1606
The Proportion of Patients Who Achieved SUVmax Reduction of 20% or More Between Baseline and Follow up Scan
The proportion of patients who achieved maximum standardized uptake value (SUVmax) reduction of 20% or more between baseline and follow up scan. It will be reported with a one-sided, 90% confidence limit.
Time frame: Baseline up to follow up, assessed up to 3 months
Change in Mean Standardized Uptake Value (SUVmean)
Will be reported as percent change with two-sided 95% confidence intervals. Paired t test will be used for pre-and post-treatment SUVs if normality assumption holds.
Time frame: Baseline up to 3 months
Neuroendocrine Tumors Visibility
Proportion of patients with visible neuroendocrine tumors at baseline out of total number of patients. The outcome will be reported as proportion and 95% CI
Time frame: At baseline
Difference in SUVmax of AMT Uptake Between the Tumor Mass and Background at Baseline
Difference will be reported as percent of (SUVmax.tumor - SUVmax.background)/SUVmax.background in the baseline scan with 95% Confidence Interval
Time frame: Baseline
| Milestone | Treatment (AMT-PET, Telotristat Etiprate) |
|---|---|
| Started | 4 |
| Completed | 4 |
| Not completed | 0 |
The proportion of patients who achieved maximum standardized uptake value (SUVmax) reduction of 20% or more between baseline and follow up scan. It will be reported with a one-sided, 90% confidence limit.
| Proportion of participants | Treatment (AMT-PET, Telotristat Etiprate) |
|---|---|
| The Proportion of Patients Who Achieved SUVmax Reduction of 20% or More Between Baseline and Follow up Scan | 0 (0 to 1) |
Will be reported as percent change with two-sided 95% confidence intervals. Paired t test will be used for pre-and post-treatment SUVs if normality assumption holds.
| Percentage change | Treatment (AMT-PET, Telotristat Etiprate) |
|---|---|
| Change in Mean Standardized Uptake Value (SUVmean) | 46.01 (-56.06 to 148.08) |
Proportion of patients with visible neuroendocrine tumors at baseline out of total number of patients. The outcome will be reported as proportion and 95% CI
| Proportion of participants | Treatment (AMT-PET, Telotristat Etiprate) |
|---|---|
| Neuroendocrine Tumors Visibility | 1 (0.51 to 1) |
Difference will be reported as percent of (SUVmax.tumor - SUVmax.background)/SUVmax.background in the baseline scan with 95% Confidence Interval
| Percentage | Treatment (AMT-PET, Telotristat Etiprate) |
|---|---|
| Difference in SUVmax of AMT Uptake Between the Tumor Mass and Background at Baseline | 451.90 (271.21 to 632.60) |
Collected over From the date of informed consent until 4 weeks after the treatment completion, up to 3 months.. Non-serious events are listed at a 5% frequency threshold.
| Group | Deaths | Serious | Other |
|---|---|---|---|
| Treatment (AMT-PET, Telotristat Etiprate) | 0/4 (0%) | 0/4 (0%) | 0/4 (0%) |
| Age, Categorical(Participants) | Treatment (AMT-PET, Telotristat Etiprate) |
|---|---|
| <=18 years | 0 |
| Between 18 and 65 years | 2 |
| >=65 years | 2 |
| Age, Continuous(years) | Treatment (AMT-PET, Telotristat Etiprate) |
|---|---|
| Median | 61 (57 to 80) |
| Sex: Female, Male(Participants) | Treatment (AMT-PET, Telotristat Etiprate) |
|---|---|
| Female | 1 |
| Male | 3 |
| Race (NIH/OMB)(Participants) | Treatment (AMT-PET, Telotristat Etiprate) |
|---|---|
| American Indian or Alaska Native | 0 |
| Asian | 0 |
| Native Hawaiian or Other Pacific Islander | 0 |
| Black or African American | 1 |
| White | 2 |
| More than one race | 0 |
| Unknown or Not Reported | 1 |
| Region of Enrollment(participants) | Treatment (AMT-PET, Telotristat Etiprate) |
|---|---|
| United States | 4 |
PDFs hosted by the registry, ClinicalTrials.gov.
Ran from Jun 2018 to primary completion in Oct 2020, 27 months.
Results were first posted in Apr 2025, 4 years 5 months after primary completion.
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This study is completed, as verified in Mar 2025. You cannot join it, but the record below documents what was studied.
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Studies of the drug tested here: Telotristat ethyl
Barbara Ann Karmanos Cancer Institute →