Nirogacestat is primarily used in the treatment of desmoid tumors, which are rare, non-cancerous but aggressive growths that can invade surrounding tissues. It functions as a gamma-secretase inhibitor, effectively blocking the Notch signaling pathway, which is often implicated in the growth and proliferation of these tumors. By inhibiting this pathway, the drug helps to reduce tumor size and control disease progression. Clinical trials have demonstrated its potential to provide significant clinical benefit, including tumor shrinkage and symptom relief, making it a promising therapeutic option for patients with desmoid tumors who are not candidates for surgery or have recurrent disease. Its targeted mechanism offers a more precise approach compared to traditional therapies, potentially reducing side effects and improving quality of life for patients.