(P 066) CHARACTERISTICS OF PATIENTS RECEIVING PEXIDARTINIB IN THE REAL-WORLD SETTING: A CROSS-SECTIONAL SURVEY

Objective: Tenosynovial giant cell tumors (TGCTs) are rare, non-malignant but locally aggressive neoplasms characterized by inflammation of the synovial lining of joints and tendons, which may cause significant symptom burden in affected patients. Pexidartinib (Turalio®) is the only systemic therapy approved by the FDA for the treatment of adult patients with symptomatic TGCT associated with severe morbidity or functional limitations, and not amenable to improvement with surgery. Because of the risk of hepatoxicity, pexidartinib is available to US patients who are registered in the Turalio Risk Evaluation and Mitigation Strategy (REMS) program. The objective of this study was to characterize demographic and clinical characteristics of patients who received pexidartinib for TGCT in the real-world setting.

Methods: Between May 2021 and July 2021, a web-based, cross-sectional survey was administered to adult patients in the Turalio REMS program who received at least 1 dose of pexidartinib, had not participated in any pexidartinib clinical trials, and could complete questionnaires in English. Information on demographics, medical history, and patient-reported outcomes was collected. Respondent characteristics were summarized descriptively and compared with patient characteristics in the phase III ENLIVEN clinical trial. No statistical testing was performed.

Results: Of 288 patients enrolled in the Turalio REMS program, 83 completed the survey (Figure 1). The mean (standard deviation [SD]) age of survey respondents was 44.2 (14.1) years, and most were female (62.7%) and White (65.1%). These demographics were comparable to those of patients enrolled in ENLIVEN (mean [SD] age, 44.5 (13.4) years; 59.2% female; 88.3% White) (Table 1).

Clinical characteristics of survey respondents and patients in ENLIVEN are summarized in Table 2. The majority of survey respondents and ENLIVEN patients had tumors in the lower extremities (88.0% vs. 91.7%), with the knee (61.4% vs. 60.8%) and ankle (12.0% vs. 17.5%) being the most affected joints. Median time from TGCT diagnosis to initiation of pexidartinib was 4.0 and 3.5 years for survey respondents and ENLIVEN patients, respectively. Prior to pexidartinib treatment, more survey respondents had at least 1 previous surgery for TGCT (74.7% vs. 52.5%) and previous imatinib treatment (20.5% vs. 8.3%) compared with patients in ENLIVEN.

Conclusion: Similarity of demographic and disease characteristics between the current study and ENLIVEN suggests that TGCT patients in real-world practice were well-represented in the ENLIVEN trial. The longer time from diagnosis to pexidartinib initiation and higher rates of surgery and off-label imatinib use in the real-world setting than ENLIVEN trial suggests that there is an unmet medical need of effective systemic treatment fulfilled by the availability of pexidartinib in these patients.

CTOS 2022 Cross Sect Survey Pt Char Abstract_06.27.22_Figure 1.docx

CTOS 2022 Cross Sect Survey Pt Char Abstract_06.27.22_Table 1.docx

CTOS 2022 Cross Sect Survey Pt Char Abstract_06.27.22_Table 2.docx