The efficacy of AMMONUL in improving patient survival at the end of an acute hyperammonemic episode was demonstrated in an uncontrolled open-label study in which 316 patients received the drug during a combined 1045 episodes of hospitalization. The study took place between 1981 and 2003 in the United States.
AMMONUL rapidly reduces elevated ammonia levels
Within four hours of initiation of AMMONUL therapy, mean ammonia levels decreased significantly and were maintained in patients responding to therapy.
How rapidly nitrogen is removed depends on the level of enzyme activity responsible for formation of hippurate and phenylacetylglutamine, which may vary by individual.
AMMONUL effectively reduces ammonia levels caused by the following enzyme deficiencies: carbamyl phosphate synthetase (CPS), ornithine transcarbamylase (OTC), argininosuccinic acid synthetase (ASS), and argininosuccinic acid lyase (ASL).
In 91% of episodes, ammonia levels decreased from very high (>4x upper limit of normal [ULN]) to lower levels after treatment. In 4% of episodes, levels shifted from high (≤4x ULN) to very high (>4x ULN).
Dialysis is recommended for those patients who fail to have a significant reduction in plasma ammonia levels within 4 to 8 hours after receiving AMMONUL.
The mean (SD) duration of treatment was 4.6 (6.45) days per episode (range 1 to 72 days).
The percentage of clinical trial patients who needed dialysis after 8 hours of AMMONUL treatment was low (13% of episodes).
AMMONUL saves lives*
Reference: -NDA 20-645 CCR Section 7.4
n-values used to calculate episode/ patient survival
*Patients who were alive at the time of hospital discharge.
ASS: argininosucciate synthetase, CPS:carbamyl phosphate sythetase
94% of all episodes (981 of 1045) were survived. Some patients in the clinical trial survived multiple episodes.
80% of patients (252 of 316) survived their last episode.
Patient survival rates for male and female OTC patients were 72% and 89% respectively, while episode survival rates for male and females OTC patients were 91% and 98%.1
AMMONUL improves or maintains neurologic status
Neurological status was improved or maintained in 93% of all episodes after treatment versus before treatment.
Recovery from coma was observed in 97% of episodes where coma was present at admission (111 of 114 episodes).
