INTRODUCTION: Tenosynovial giant cell tumor (TGCT) is a benign clonal neoplastic 
proliferation arising from the synovium often causing pain, swelling, joint 
stiffness, and reduced quality of life. The optimal treatment strategy in 
patients with diffuse-type TGCT (dt-TGCT) is evolving. Surgery is the main 
treatment, with a high recurrence rate and surgery-related morbidity. 
Radiotherapy is associated with important side effects. TGCT cells overexpress 
colony-stimulating factor 1 (CSF1). Pexidartinib (Turalio™) is a selective 
CSF1 R inhibitor, which was recently approved by the FDA for the treatment of 
TGCT.
AREAS COVERED: This article reviews the pharmacological properties, clinical 
efficacy, and safety of pexidartinib.
EXPERT OPINION: Pexidartinib was effective with an acceptable safety profile for 
advanced TGCT in phase I-III studies. The phase III trial (ENLIVEN) in 
unresectable TGCT met its primary endpoints of overall response rate. These 
results led to FDA approval for this TGCT population. Mixed or cholestatic 
hepatotoxicity was observed in rare cases. For this reason, pexidartinib is 
currently available only through a Risk Evaluation and Mitigation Strategy 
(REMS) Program in the USA. TGCT significantly impairs patients' quality of life. 
The approval of pexidartinib has changed the therapeutic armamentarium for this 
condition. However, strict monitoring of liver function is warranted.