Conclusions
Application of topical mometasone prior to SC elamipretide administration demonstrated a significant reduction in ISR signs induced by elamipretide and did not cause significant changes in elamipretide plasma exposure or additional adverse events. Further investigation of mometasone is warranted for mitigation of elamipretide-induced ISRs and improving compliance. Treatment options that target mast cell activation may ameliorate elamipretide ISRs and should also be explored in future studies.