Drug approved as adjunctive therapy for treatment of elevated blood ammonia levels

Carglumic acid tablets (Carbaglu, Orphan Europe) for treatment of a rare genetic condition characterized by excess ammonia in the blood have received FDA approval.

The metabolic disorder N-acetylglutamate synthase (NAGS) deficiency can present in infants shortly after birth. If not treated swiftly, NAGS deficiency and elevated ammonia levels (hyperammonemia) can be deadly. NAGS diagnosis can be confirmed by DNA testing.

In a study of 23 patients with NAGS who were administered carglumic acid for periods ranging from 6 months to 21 years, carglumic acid lowered blood ammonia levels within 24 hours and normalized ammonia levels within 3 days. Given long-term treatment, most of the patients in the study seemed to sustain normal plasma ammonia levels.

The recommended initial dose of carglumic acid is 100 to 250 mg/kg daily. Use of other ammonia-lowering therapies is recommended for the treatment of acute hyperammonemia.

Adverse events associated with the drug include vomiting, fever, anemia, abdominal pain, tonsillitis, diarrhea, headache, and ear infection. Healthcare professionals are urged to call FDA’s MedWatch program at 800-FDA-1088 to report adverse events.