Because of the deteriorating medical status of this patient and the presence of CCDC6-RET fusion mutation in his tumor, we started a weekly cycled schedule for reduced selpercatinib dose with the addition of MitoQ: selpercatinib 160 mg twice a day (BID) on days 1, 2 (off days 3, 4, 5, 6, 7) followed by MitoQ 20 mg daily (QD) on days 3, 4, 5, 6, 7 (off days 1, 2) (Fig. 4a). The gene discussed is RET; the disease is neoplasm.