Larotrectinib is an orally administered inhibitor of tropomyosin receptor kinase (Trk), a receptor tyrosine kinase activated by neurotrophins which is mutated in a variety of cancer cell types and plays an important role in tumor cell growth and survival.[L49821] Upon administration, larotrectinib binds to Trk, thereby preventing neurotrophin-Trk interaction and Trk activation, which results in both the induction of cellular apoptosis and the inhibition of cell growth in tumors that overexpress Trk.[L49821] Larotrectinib was granted accelerated approval by the FDA in November 2018 for the treatment of Trk-positive solid tumors. It was notable for being the second tissue-agnostic chemotherapy ever approved by the FDA.[L4847]