Phase 3 Study of Pexidartinib for Pigmented Villonodular Synovitis (PVNS) or Giant Cell Tumor of the Tendon Sheath (GCT-TS) (ENLIVEN)

This is a Phase 3 clinical study, which aims to evaluate the effectiveness of an investigational drug called pexidartinib for the treatment of certain tumors for which surgical removal could cause more harm than good.

The main purpose of this study is to gather information about the investigational drug pexidartinib, which may help to treat tumors of pigmented villonodular synovitis (PVNS) or giant cell tumor of the tendon sheath (GCT-TS).

The study consists of two parts with a follow-up period. In Part 1, eligible study participants will be assigned to receive either pexidartinib or matching placebo for 24 weeks. A number of assessments will be carried out during the course of the study, including physical examinations, blood tests, imaging studies, electrocardiograms, and questionnaires. MRI scans will be used to evaluate the response of the tumors to the treatment. Some subjects, assigned to placebo in Part 1 transitioned to pexidartinib for Part 2.

Then a protocol amendment was written to allow only pexidartinib patients to continue into Part 2. Part 2 is a long-term treatment phase in which all participants receive open-label pexidartinib. There was also a follow-up period added to Part 2.


Study Type: Interventional  (Clinical Trial)
Actual Enrollment: 120 participants
Allocation: Randomized
Intervention Model: Parallel Assignment
Intervention Model Description: Parallel assignment in Part 1, Single treatment in Part 2
Masking: Quadruple (Participant, Care Provider, Investigator, Outcomes Assessor)
Masking Description: Quadruple (Participant, Care Provider, Investigator, Outcomes Assessor) in Part 1, Open-label (no masking) in Part 2
Primary Purpose: Treatment
Official Title: A Double-blind, Randomized, Placebo-controlled Phase 3 Study of Orally Administered PLX3397 in Subjects With Pigmented Villonodular Synovitis or Giant Cell Tumor of the Tendon Sheath
Actual Study Start Date: March 2015
Estimated Primary Completion Date: December 2018
Estimated Study Completion Date: December 2018

Arm:
- Experimental: Part 1 - Pexidartinib
- Placebo Comparator: Part 1 - Placebo
- Experimental: Part 2 - All Pexidartinib
- Experimental: Part 2 - Placebo-Pexidartinib