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betaine anhydrousCareFirst (Caremark)

Methylmalonic acidemia with homocystinuria

Initial criteria

  • Diagnosis of homocystinuria confirmed by enzyme assay or genetic testing demonstrating one of the following: cystathionine beta-synthase (CBS) deficiency, 5,10-methylenetetrahydrofolate reductase (MTHFR) deficiency, or cobalamin cofactor metabolism (cbl) defect
  • If the member has CBS deficiency, plasma methionine concentrations are monitored and kept below 1,000 micromol/L through dietary modification, and if necessary, a reduction in dose for the requested medication
  • Medication is prescribed by or in consultation with a physician who specializes in metabolic disease and/or lysosomal storage disorders
  • For methylmalonic acidemia with homocystinuria: diagnosis of methylmalonic acidemia with homocystinuria

Reauthorization criteria

  • For homocystinuria: total homocysteine level is undetectable or present only in small amounts OR there is a substantial decrease in homocysteine levels and the dose will be increased until maximum tolerability or plasma total homocysteine is undetectable or present in only small amounts
  • If the member has CBS deficiency, plasma methionine concentrations are monitored and kept below 1,000 micromol/L through dietary modification, and if necessary, a reduction in dose for the requested medication
  • For methylmalonic acidemia with homocystinuria: member is experiencing benefit from therapy as evidenced by disease stability or disease improvement

Approval duration

12 months