Drug Interactions between Bylvay and Voxzogo

MONITOR: Odevixibat may affect absorption of fat-soluble vitamins (FSV) including vitamin A, D, E, and K. In clinical studies, new onset or worsening of existing FSV deficiency was reported in 5% of placebo-treated patients, and in 16% of odevixibat-treated 120 mcg/kg/day patients. However, none of the odevixibat-treated 40 mcg/kg/day patients had new onset or worsening of existing FSV deficiency.

MANAGEMENT: Clinical and laboratory monitoring of FSV levels is recommended at baseline and during treatment with odevixibat. If FSV deficiency is diagnosed, supplement with FSV. Odevixibat should be discontinued if FSV deficiency persists or worsens despite adequate FSV supplementation.

MONITOR: Vosoritide may cause transient decreases in blood pressure. In clinical trials, 13% of patients treated with vosoritide experienced a transient decrease in blood pressure compared to 5% of patients on placebo. The median time to onset from injection was 31 (18 to 120) minutes with resolution within 31 (5 to 90) minutes. Two out of 60 (3%) vosoritide-treated patients each had one symptomatic episode of decreased blood pressure with vomiting and/or dizziness compared to 0 of 61 (0%) patients on placebo.

MANAGEMENT: To reduce the risk of low blood pressure and its associated signs and symptoms, patients should have adequate food intake before vosoritide administration and should drink approximately 240 to 300 mL of fluid within the hour prior to vosoritide administration. Patients should be advised to avoid rising abruptly from a sitting or recumbent position and to notify their doctor if they experience fatigue, nausea, dizziness, or lightheadedness.