SCH66336, also known as Lonafarnib, is primarily used in cancer research as a potent and selective inhibitor of farnesyltransferase. This enzyme plays a critical role in the post-translational modification of proteins, including Ras proteins, which are often mutated in various cancers. By inhibiting farnesyltransferase, SCH66336 disrupts the activation of Ras signaling pathways, thereby inhibiting the proliferation and survival of cancer cells. It has been studied in preclinical and clinical trials for its potential therapeutic effects in treating solid tumors and hematologic malignancies. In 2020, SCH66336 was approved by the FDA for the treatment of Hutchinson-Gilford progeria syndrome (HGPS), a rare genetic disorder caused by a mutation in the LMNA gene leading to abnormal farnesylation. Additionally, SCH66336 has been explored for its ability to enhance the efficacy of other anticancer therapies when used in combination treatments. Its application extends to studying the molecular mechanisms of Ras-driven cancers, progeria, and other conditions involving dysregulated protein farnesylation, as well as developing targeted therapies.