A Phase 2 interventional study of Nirogacestat oral tablet in Desmoid Tumor and Aggressive Fibromatosis, sponsored by SpringWorks Therapeutics, Inc., a healthcare company of Merck KGaA, Darmstadt, Germany. Active, not recruiting at 3 sites in Japan. Open to participants aged 18 Years and older. Per ClinicalTrials.gov, last updated 2026-09-15.
Sponsored by SpringWorks Therapeutics, Inc., a healthcare company of Merck KGaA, Darmstadt, Germany · Phase 2, Interventional, and Treatment
This study is being conducted to characterize the efficacy and safety of nirogacestat in Japanese adults with progressing desmoid tumors/aggressive fibromatosis.
Desmoid tumors, also referred to as aggressive fibromatosis, are rare, locally invasive, slow growing soft tissue tumors. Although considered benign because of their inability to metastasize, desmoid tumors can cause significant morbidity and occasionally mortality in patients.
Nirogacestat is a tumor inhibitor that works by slowing or stopping the growth of tumor cells. Nirogacestat is a tablet taken by mouth and has been approved in the USA for adult patients with progressing desmoid tumors who require systemic treatment.
This is an open-label study to characterize the efficacy and safety of nirogacestat in Japanese adults with progressing desmoid tumors/aggressive fibromatosis (DT).
Key Inclusion Criteria:
Participant has:
Key Exclusion Criteria:
Nirogacestat 150 mg by mouth, twice daily
Drug: Nirogacestat oral tablet
Nirogacestat tablet
Also known as: PF-03084014, Ogsiveo
Objective response rate (ORR)
Objective response rate (ORR), defined as the proportion of participants with confirmed complete response (CR) + partial response (PR) assessed by independent Central Imaging Review using RECIST v1.1 (Eisenhauer 2009).
Time frame: On the first day of every 3 cycles (each cycle is 28 days) until disease progression is observed or death, assessed up to approximately 3 years.
Duration of response (DoR)
Duration of response (DoR), defined as the time from the first objective response (CR or PR) that is subsequently confirmed until the first occurrence of disease progression (radiographic or clinical) by RECIST v1.1 or death by any cause (whichever occurs first).
Time frame: On the first day of every 3 cycles (each cycle is 28 days) until disease progression is observed or death, assessed up to approximately 3 years.
Time to Response (TTR)
Time to Response (TTR), defined as the time interval between the first dose of study treatment and the first date of objective response that is subsequently confirmed.
Time frame: On the first day of every 3 cycles (each cycle is 28 days) until disease progression is observed or death, assessed up to approximately 3 years.
Safety endpoints will include incidence of treatment-emergent adverse events (TEAEs), changes in laboratory parameters, vital signs, physical examination findings, and ECGs.
Tolerability will be assessed according to toxicities graded by NCI CTCAE v5.0.
Time frame: On the first day of every 3 cycles (each cycle is 28 days) until disease progression is observed or death, assessed up to approximately 5 years.
Progression Free Survival (PFS)
Progression Free Survival (PFS) is defined as the time from the start of study treatment until the date of assessment of progression or death by any cause. Progression will be determined radiographically using RECIST v1.1 (Eisenhauer 2009) or clinically as assessed by the investigator. Clinical progression is defined as the onset or worsening of symptoms resulting in a global deterioration of health status causing the permanent discontinuation from study treatment and the initiation of emergent treatment (e.g., radiotherapy, surgery, or systemic therapy, including chemotherapy or tyrosine kinase inhibitors) for DT.
Time frame: On the first day of every 3 cycles (each cycle is 28 days) until disease progression is observed or death, assessed up to approximately 3 years.
Symptoms and impacts will be assessed by evaluating change from baseline at Cycle 10 on the following patient reported outcomes (PROs):
* Brief Pain Inventory (BPI) short form * European Organization for Research and Treatment of Cancer (EORTC) Quality of Life Questionnaire-Core 30 (QLQ-C30)
Time frame: On the first day of every 3 cycles (each cycle is 28 days) until disease progression is observed or death, assessed up to approximately 3 years.
Characterize nirogacestat serum concentrations.
Time frame: On the first day of the first cycle and of every third cycles (each cycle is 28 days) until disease progression is observed or death, assessed up to approximately 3 years.
Plan to share: Yes — IPD supporting publicly available results will be evaluated for sharing.
Supporting information: Study protocol, Sap, Csr, Analytic code
This study is active, not recruiting, as verified in Sep 2026. You cannot join it, but the record below documents what was studied.
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SpringWorks Therapeutics, Inc., a healthcare company of Merck KGaA, Darmstadt, Germany