ABSTRACT
Achondroplasia, characterized by short stature and skeletal abnormalities, is caused by a gain-of-function variant in the fibroblast growth factor receptor 3 gene. Vosoritide, a C-type natriuretic peptide analog, is an emerging treatment for achondroplasia that functions by promoting endochondral ossification. Vosoritide was approved for the treatment of achondroplasia in Europe and the United States in 2021, and in Japan, the following year. However, vosoritide is associated with a risk of hypotension and vomiting after subcutaneous injection due to its vasodilating effect. Herein, we present two cases of cardiovascular adverse events in infants following vosoritide injection. Case 1 involved a one-month-old female infant with achondroplasia who received the first subcutaneous injection of vosoritide 30 minutes after her last formula intake. Following injection, she developed transient symptomatic hypotension accompanied by vomiting. Although established guidelines recommend that injections be administered after approximately 30 minutes (Europe/Japan) or within one hour (USA) following the last feeding, an extended interval of 1.5 to two hours was required to prevent hypotension-associated vomiting. Case 2 involved a three-month-old female infant with achondroplasia. The first subcutaneous vosoritide injection was administered four hours after the last formula intake, and she subsequently developed prolonged compensated shock with marked tachycardia requiring intervention, including repetitive bolus saline injection. These cases indicate the need to monitor patients for cardiovascular adverse events following subcutaneous injection of vosoritide in early infancy.
ABSTRACT
Safety information on diazoxide for pregnant and lactating women with hypoglycemia is limited. In this case report, we assessed diazoxide concentrations in maternal and infant blood, cord blood, and breast milk. We described a 30-year-old pregnant woman diagnosed with hypoglycemia due to nesidioblastosis at 4 months of age. Before becoming pregnant, she was treated with oral diazoxide (75-375 mg). All medications were discontinued after she was discovered to be pregnant. During gestational week 25, diazoxide treatment was resumed at 150-175 mg daily for repeated hypoglycemic episodes. Diazoxide administration was continued in combination with diet treatment until delivery. Glucose levels were well controlled. During gestational week 40, a male infant weighing 3069 g was delivered via spontaneous vaginal delivery with no pregnancy or neonatal complications. Diazoxide concentrations detected in maternal serum at 2.5-11.6 h after oral treatment ranged from 12.4 to 32.7 µg/mL. In cord blood, the diazoxide concentration was 18.5 µg/mL at 7.2 h after the last dose. During lactation, no hypoglycemia or hyperglycemia was observed. The approximate calculated ratio of diazoxide in breast milk and maternal serum was 0.09. The calculated daily infant dose was 0.47 mg/kg/day. The relative infant dose via breast milk ranged from 3.1% to 5.9%. Diazoxide transferred from maternal blood to the fetus across the placenta. It also transferred into breast milk, but there were no harmful effects on the infant.
