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NCT04996004 · ClinicalTrials.gov registry record · Phase 2
A Study to Learn About the Study Medicine (Called Ontorpacept or TTI-621) Given Alone and in Combination With Doxorubicin in People With Leiomyosarcoma
A Phase 2 study, sponsored by Pfizer.
- Terminated
- Registry status
- Phase 2
- Development phase
- 76
- Enrollment target
NCT04996004: Clinical Trial Phase 2 study, sponsored by Pfizer.
NCT04996004 is a Phase 2 study that was terminated before completion, run by Pfizer. The registered enrollment target is 76 participants, below the 133-participant average among 30,622 other Phase 2 trials with a reported enrollment target (43% lower). According to ClinicalTrials.gov, the official US trial registry.
The verdict
NCT04996004, a Phase 2 study, was terminated before completion, sponsored by Pfizer.
- TERMINATED
- Registry status
- Phase 2
- Development phase
- 76 participants
- Enrollment target
Study Summary
The purpose of this study is to learn about the safety and effects of the study medicine (called Ontorpacept or TTI-621) when given alone and when given in combination with doxorubicin for people with leiomyosarcoma. Leiomyosarcoma is a tumor of the smooth muscles. This study is seeking participants who have: * leiomyosarcoma that is advanced or has spread to other parts of the body (metastatic) * not received prior treatment with anthracyclines (a drug commonly used in patients with some kinds of cancer, including leiomyosarcoma) * not received more than one prior treatment for their leiomyosarcoma During the first 18 weeks of this study, participants will receive doxorubicin by IV infusion (given directly into a vein) at the study clinic every 3 weeks for a total of 6 doses. Participants will also receive Ontorpacept (TTI-621) by IV infusion at the study clinic on the same day as doxorubicin and again one week later for the first 18 weeks. After the first 18 weeks, participants will stop receiving doxorubicin but will continue receiving Ontorpacept (TTI-621) as IV infusion every 14 days at the study clinic. They will keep receiving Ontorpacept (TTI-621) until their cancer is no longer responding to treatment. We will examine the experiences of participants receiving Ontorpacept (TTI-621) in combination with doxorubicin in the first 18 weeks and then Ontorpacept (TTI-621) by itself after the doxorubicin is stopped. This will help us determine if the study medicine Ontorpacept (TTI-621) given with doxorubicin and then by itself is safe and effective. Participants will be involved in the study for approximately one year, depending on how their cancer responds to the study treatment. They will have study visits about 12 times in the first 18 weeks (when the study medicine Ontorpacept is given with doxorubicin) and then every two weeks after the doxorubicin is stopped and the study medicine Ontorpacept (TTI-621) is given by itself.
Primary Outcome
An adverse event (AE) was any untoward medical occurrence or worsening of a pre-existing medical condition following or during exposure to pharmaceutical product, whether or not considered causally related to product. A serious adverse event (SAE) was an adverse event occurred during any study at any dose of the investigational products that fulfils one or more of following criteria: resulted in death; was life-threatening; required inpatient hospitalization or prolongation of hospitalization; r
Interventions
- DRUG Doxorubicin
- DRUG Ontorpacept (TTI-621)
Trial Details
| Field | Value |
|---|---|
| Enrollment Target | 76 participants |
| Start Date | 2021-06-22 |
| Est. Completion | 2023-12-07 |
| Phase | Phase 2 |
Why NCT04996004 stopped before completion
NCT04996004 is an interventional study that assigns participants to a tested intervention. The registry caps enrollment at 76 participants, a relatively small participant target, below the 133-participant average among 30,622 other Phase 2 trials with a reported enrollment target (43% lower).
The record links to 0 conditions, and to 2 interventions - of which Doxorubicin is the first listed.
NCT04996004 does not publish any study locations in the registry export this page uses.
Frequently Asked Questions
What is clinical trial NCT04996004 about?
NCT04996004 is a clinical study titled "A Study to Learn About the Study Medicine (Called Ontorpacept or TTI-621) Given Alone and in Combination With Doxorubicin in People With Leiomyosarcoma". The purpose of this study is to learn about the safety and effects of the study medicine (called Ontorpacept or TTI-621) when given alone and when given in combination with doxorubicin for people with leiomyosarcoma. Leiomyosarcoma is a tumor of the smooth muscles. This study is seeking participant...
What is the current status of trial NCT04996004?
This trial is currently terminated. It is a Phase 2 study. The enrollment target is 76 participants. The study started on 2021-06-22. Estimated completion is 2023-12-07.
What interventions are being tested in trial NCT04996004?
The interventions under investigation include: Doxorubicin (DRUG), Ontorpacept (TTI-621) (DRUG).
Who is sponsoring clinical trial NCT04996004?
This trial is sponsored by Pfizer, which has 1,845 total clinical trials registered on ClinicalTrials.gov.
Learn More About Clinical Trials
How this trial's enrollment target compares
Where NCT04996004's enrollment target sits among peer trials
76 893rd of 2000 higher than 1,101 of 2,000 other Phase 2 trials
participants (enrollment target), bucketed by value
Each bar is a band; taller bars hold more other Phase 2 trials. The dashed line + filled bar mark this entry. Hover or tap any bar for its full count and share, and where it sits relative to this entry.
Source ClinicalTrials.gov registry export · 2026-08-08
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