NTRK1 and neoplasm: Interestingly, while 1st- and next-generation TRK inhibitors were similarly potent against this model in vitro (Supplementary Fig. 6), a 30-fold higher dose of larotrectinib and selitrectinib (30 mg/kg BID versus 1 mg/kg BID) was necessary to achieve the same effect on tumor growth inhibition observed with zurletrectinib in vivo.