Betaine

CYSTADANE ® is indicated for the treatment of homocystinuria to decrease elevated homocysteine blood concentrations in pediatric and adult patients. Included within the category of homocystinuria are: Cystathionine beta-synthase (CBS) deficiency 5,10-methylenetetrahydrofolate reductase (MTHFR) deficiency Cobalamin cofactor metabolism (cbl) defect CYSTADANE is a methylating agent indicated in pediatric and adult patients for the treatment of homocystinuria to decrease elevated homocysteine blood concentrations. Included within the category of homocystinuria are: Cystathionine beta-synthase (CBS) deficiency 5,10-methylenetetrahydrofolate reductase (MTHFR) deficiency Cobalamin cofactor metabolism (cbl) defect

CYSTADANE acts as a methyl group donor in the remethylation of homocysteine to methionine in patients with homocystinuria. Betaine occurs naturally in the body. It is a metabolite of choline and is present in small amounts in foods such as beets, spinach, cereals, and seafood.

Adults and Pediatric Patients 3 Years of Age and Older The recommended dosage is 6 grams per day, administered orally in divided doses of 3 grams twice daily. Pediatric Patients Less than 3 Years of Age The recommended starting dosage is 100 mg/kg/day, administered orally in divided doses of 50 mg/kg twice daily, and then increased weekly by 50 mg/kg increments. Monitor patient response by plasma homocysteine concentrations. Increase the dosage gradually until the plasma total homocysteine concentration is undetectable or present only in small amounts. Preparation and Administration Instructions Prescribed amount of CYSTADANE should be measured with the measuring scoop provided and then dissolved in 4 to 6 ounces of water, juice, milk, or formula until completely dissolved, or mixed with food for immediate ingestion.

None. None

Hypermethioninemia in Patients with CBS Deficiency: CYSTADANE may worsen elevated plasma methionine concentrations and cerebral edema has been reported. Monitor plasma methionine concentrations in patients with CBS deficiency. Keep plasma methionine concentrations below 1,000 micromol/L through dietary modification and, if necessary, a reduction of CYSTADANE dosage.

The following serious adverse reactions are described elsewhere in labeling: Hypermethioninemia and cerebral edema in patients with CBS deficiency. Most common adverse reactions (> 2%) are: nausea and gastrointestinal distress, based on physician survey.

Storage Store at room temperature, 15 to 30 ˚C (59 to 86 ˚F). Protect from moisture.