mavacamten will lower the extent or impact of ethinylestradiol by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. Progestin and ethinyl estradiol are CYP3A4 substrates. Mavacamten may possibly lessen systemic exposures of ethinyl estradiol and progestin, which may bring about contraceptive failure or an increase … Read More