Skip to content

Long-term Outcome of N-Carbamylglutamate Treatment in Propionic Acidemia and Methylmalonic Acidemia

Long-term Outcome of N-Carbamylglutamate Treatment in Propionic Acidemia and Methylmalonic Acidemia

Status
Terminated
Phases
Phase 2
Study type
Interventional
Source
ClinicalTrials.gov
Registry ID
NCT01597440
Enrollment
1
Registered
2012-05-14
Start date
2012-09-30
Completion date
2015-02-28
Last updated
2017-04-26

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Methylmalonic Acidemia, Propionic Acidemia

Keywords

Propionic acidemia (PA), Methylmalonic acidemia (MMA), Carbaglu NCG, Hyperammonia

Brief summary

Background: Very few drugs exist that treat hyperammonemia, specifically PA and MMA. Diet restrictions and alternate pathway agents are the current primary treatments, but they frequently fail to prohibit brain damage. Orthotopic liver transplantation cures the hyperammonemia of urea cycle disorders, but organ availability is limited and the procedure is highly invasive and requires life-long immunosuppression. A drug that could repair or stimulate a dysfunctional urea cycle such as this would have several advantages over current therapy. A drug called N-carbamyl-L-glutamate, Carglumic acid (NCG or Carbaglu)has recently been found to be virtually curative of another urea cycle defect called NAGS deficiency. In this disorder, treatment with NCG alone normalizes ureagenesis, blood ammonia and glutamine levels, allows normal protein tolerance and restores health. Knowledge from this study is being applied to acquired hyperammonemia, specifically in patients with propionic PA and MMA, to try and improve neurodevelopmental outcomes by improving the hyperammonemia. Aims: The overall objective of this project is to determine whether treatment of acute hyperammonemia with Carglumic acid in propionic acidemia (PA), methylmalonic acidemia (MMA) changes the long-term outcome of disease and to determine if it is effective in restoring urine ammonia levels to normal levels.

Detailed description

Methods/Design This 5-year, Phase II, double-blind study aims to recruit and enroll 34 PA and MMA patients during acute episodes of hyperammonemia. The primary aim is to circumvent the long-term neurodevelopmental decline due to having a prolonged levels of ammonia during crisis in the blood and urine. After treatment and crisis resolution with Carbaglu or placebo and standard of care therapy, measures of neurodevelopmental outcomes (Bayley II and Functional Status Scale) are being measured at 9, 15,21 and 30 months post-discharge from the hospital. Safety of NCG treatment will also be monitored as measured by close examination of adverse events and laboratory blood tests. To test for the effectiveness of NCG, longitudinal models to evaluate the groupwise difference (NCG vs. Placebo) in the trajectory of change in neurodevelopmental outcomes and safety analyses between drug and placebo patients. Subsequent Episodes At any time after the initial episode, participants may present to the hospital with PA- or MMA-associated symptoms. If the plasma ammonia level verified as a bonafide episode of HA (plasma ammonia is ≥ 100 µmol/l), that participant will receive the same study medication that they received during their initial episode in a double-blinded fashion, (i.e. If the participant received NCG at the time of initial randomization, he/she will continue to receive NCG at each subsequent HA episode. If the participant received PLBO at the time of initial randomization, he/she will continue to receive PLBO at each subsequent HA episode). Only the pharmacist will know if the participant receives NCG or PLBO. The same study assessments (previously stated) will be conducted at each qualifying HSA episode.

Interventions

Active NCG & Standard of Care Chemical Composition: N-carbamyl-L-glutamic acid (NCG) The daily dose will be 100 mg/kg/ day. The doses are to be divided into 2 equal doses and administered orally or enterally by nasogastric or gastrostomy tube (standard of care will prevail when choosing the mode of drug administration). The tablets must be dispersed in a minimum of 2.5-10 ml of water and ingested immediately or administered by fast push through a syringe via a nasogastric or gastrostomy tube. The suspension has a slightly acidic taste. This drug will be administered for 7 days after admission or until discharge (whichever is sooner).

OTHERStandard of Care

Standard of Care

Sponsors

Children's National Research Institute
CollaboratorOTHER
Boston Children's Hospital
CollaboratorOTHER
University Hospitals Cleveland Medical Center
CollaboratorOTHER
University of California, Los Angeles
CollaboratorOTHER
Children's Hospital of Philadelphia
CollaboratorOTHER
Lucile Packard Children's Hospital
CollaboratorOTHER
University of Colorado, Denver
CollaboratorOTHER
Mendel Tuchman
Lead SponsorOTHER

Study design

Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
TREATMENT
Masking
QUADRUPLE (Subject, Caregiver, Investigator, Outcomes Assessor)

Eligibility

Sex/Gender
ALL
Age
1 Hours to 4 Weeks
Healthy volunteers
No

Inclusion criteria

* Aged 4 weeks or younger (0-28 days) * \>36 weeks gestational age at birth * Birth weight ≥2500 g * Plasma ammonia level at presentation \>150 mcmol/L * PA or MMA presumed or established diagnosis as follows (one of the following): 1. Acidosis at presentation, pH \<7.3 OR 2. Plasma acylcarnitine analysis either alone or as part of newborn screening, demonstrating C3 \>4 mcmol/L OR 3. Diagnosed, or sibling diagnosed with PA by semi-quantitative urine organic acid analysis, defined as presence of elevated methylcitric acid and no evidence of biotin related disorders in the organic acid analysis OR 4. Diagnosed, or sibling diagnosed with MMA by semi-quantitative urine organic acid analysis, defined as elevation of methylmalonic acid and no evidence of vitamin B12 dependent disorder on plasma amino acid analysis * Able to receive medications orally, by nasogastric (NG)-tube or by gastric (G)-tube * No concomitant illness which would preclude safe participation as judged by the investigator * Signed informed consent by the subject's legally acceptable representative * After initial enrollment, criteria 3 or 4 (definitive diagnosis of the patient) must be fulfilled prior to discharge from initial admission in order to remain in the study.

Exclusion criteria

* Had any prior hyperammonemic episode * Administration of NCG within 7 days of participation in the study * Use of any other investigational drug, biologic, or therapy, with the exception of sodium benzoate or sodium phenylacetate if the latter were administered prior to diagnosis by acylcarnitine analysis (diagnostic inclusion criterion 2), or organic acid analysis (diagnostic inclusion criteria 3 & 4) * Planned participation in any other clinical trial * Diagnosis of any medical condition causing hyperammonemia which is not PA or MMA. * Any clinical or laboratory abnormality or medical condition that, at the discretion of the investigator, may put the subject at an additional risk by participating in this study * Had a liver transplant or is scheduled for a liver transplant * Is not expected to be compliant with this study in terms of returning to site for subsequent episodes of hyperammonemia crises or for long-term follow-up

Design outcomes

Primary

MeasureTime frameDescription
Neurodevelopment30 monthsNeurodevelopmental outcome as measured by Cognitive Composite (Bayley III), Motor Composite (Bayley III) and Functional Status Scale and safety of NCG treatment as measured by adverse events and laboratory blood tests

Secondary

MeasureTime frameDescription
Number of Participants With Adverse EventsStart of episode through 7 days or discharge (if earlier)Safety is measured by tracking and detailing the number and type of adverse events and their severity based on the CTCAE.

Countries

United States

Participant flow

Participants by arm

ArmCount
Carbaglu
Active NCG & Standard of Care N-carbamylglutamate: Active NCG & Standard of Care Chemical Composition: N-carbamyl-L-glutamic acid (NCG) The daily dose will be 100 mg/kg/ day. The doses are to be divided into 2 equal doses and administered orally or enterally by nasogastric or gastrostomy tube (standard of care will prevail when choosing the mode of drug administration). The tablets must be dispersed in a minimum of 2.5-10 ml of water and ingested immediately or administered by fast push through a syringe via a nasogastric or gastrostomy tube. The suspension has a slightly acidic taste. This drug will be administered for 7 days after admission or until discharge (whichever is sooner). Standard of Care: Standard of Care
1
Placebo
Standard of Care therapy Standard of Care: Standard of Care
0
Total1

Baseline characteristics

CharacteristicCarbagluTotal
Age, Categorical
<=18 years
1 Participants1 Participants
Age, Categorical
>=65 years
0 Participants0 Participants
Age, Categorical
Between 18 and 65 years
0 Participants0 Participants
Age, Continuous4 days
STANDARD_DEVIATION 0
4 days
STANDARD_DEVIATION 0
NH3223 mcmol/L
STANDARD_DEVIATION 0
223 mcmol/L
STANDARD_DEVIATION 0
Region of Enrollment
United States
1 participants1 participants
Sex: Female, Male
Female
0 Participants0 Participants
Sex: Female, Male
Male
1 Participants1 Participants

Adverse events

Event typeEG000
affected / at risk
EG001
affected / at risk
deaths
Total, all-cause mortality
— / —— / —
other
Total, other adverse events
1 / 10 / 0
serious
Total, serious adverse events
0 / 10 / 0

Outcome results

Primary

Neurodevelopment

Neurodevelopmental outcome as measured by Cognitive Composite (Bayley III), Motor Composite (Bayley III) and Functional Status Scale and safety of NCG treatment as measured by adverse events and laboratory blood tests

Time frame: 30 months

Population: The study was closed prematurely. There is no analysis population.

Secondary

Number of Participants With Adverse Events

Safety is measured by tracking and detailing the number and type of adverse events and their severity based on the CTCAE.

Time frame: Start of episode through 7 days or discharge (if earlier)

ArmMeasureValue (NUMBER)
CarbagluNumber of Participants With Adverse Events1 Participants

Source: ClinicalTrials.gov · Data processed: Feb 4, 2026