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CompletedNCT01599286STOUpdated Feb 15, 2021Results posted

Short-Term Outcome of N-Carbamylglutamate in the Treatment of Acute Hyperammonemia

A Phase 2 interventional study of Carbaglu and Placebo in Propionic Acidemia, Type I and/or Type II, Methylmalonic Acidemia and Carbamoyl-Phosphate Synthase I Deficiency Disease, sponsored by Mendel Tuchman. Completed at 9 sites in United States. Open to participants aged 1 Week to 99 Years. Per ClinicalTrials.gov, last updated 2021-02-15.

Sponsored by Mendel Tuchman · Phase 2, Interventional, and Treatment

Phase
Phase 2
Study type
Interventional
Enrollment
35
Allocation
Randomized
Ages
1 Week to 99 Years
Sex
All
01

Study summary

The overall objective of this drug trial is to determine whether the treatment of acute hyperammonemia with N-carbamyl-L-glutamate (NCG, Carglumic acid) in propionic acidemia (PA), methylmalonic acidemia (MMA), late-onset CPS1 deficiency (CPSD) and late-onset Ornithine transcarbamylase deficiency (OTCD) accelerates the resolution of hyperammonemia efficiently and safely.

The primary goal is to determine if the study drug (NCG) efficiently reduces ammonia levels following a hyperammonemia episode(s).

Secondly, the investigators want to know if treatment with this study drug (NCG) efficiently improves neurologic function, reduces plasma glutamine levels and lessens the duration of hospitalization after each episode of hyperammonemia.

Read the detailed description

This is a double-blind, placebo-controlled, randomized clinical drug trial to evaluate the efficacy of NCG in the treatment of two organic acidemias (severe PA and MMA), and two urea-cycle disorders (late-onset CPSD and OTCD).

Primarily, the investigators want to determine whether NCG treatment of acute hyperammonemia in severe, neonatal-onset PA, MMA, CPSD, and OTCD is efficacious and whether it is safe. The investigators will approach this task in two ways.

  1. Assess Whether NCG Treatment is Effective

    The objective of this study is to assess whether NCG is efficacious in treating hyperammonemia and improving outcome:

    The investigators will realize this goal by randomizing each hyperammonemic episode from every subject to NCG (NCG)+standard treatment (NCG-STD) versus placebo+standard treatment (PLBO-STD) and subsequently gauging response with the primary outcome of plasma ammonia levels, in addition to the plasma glutamine, the Functional Status Scale, and the length of hospitalization.

  2. Safety

The primary safety outcome of the study will be the assessed via the rate of Serious Adverse Events (SAEs), defined in this study as death or substantial prolongation of hospitalization, as patients are hospitalized as part of the entry to the study.

Safety tests consisting of complete blood count (CBC), liver and kidney function tests, and coagulation profile (PTT/INR) will be performed before treatment, between days 3-5 of treatment, and just prior to discontinuation of NCG. An electrocardiogram will be performed before treatment and on the third day of treatment or before discharge if earlier.

02

Conditions studied

  • Propionic Acidemia, Type I and/or Type II
  • Methylmalonic Acidemia
  • Carbamoyl-Phosphate Synthase I Deficiency Disease
  • Ornithine Carbamoyltransferase Deficiency

Keywords

  • Hyperammonemia
  • Propionic Acidemia (PA)
  • Methylmalonic Acidemia (MMA)
  • Late-Onset CPS1 Deficiency (CPSD)
  • Late-Onset Ornithine Transcarbamylase Deficiency (OTCD)
  • Carbaglu
03

Who can participate

Ages eligible
1 Week to 99 Years
Sexes eligible
All
Accepts healthy volunteers
No

Inclusion criteria

o Aged older than 1 week with an established diagnosis of CPSD or OTCD (as follows):

  • Diagnosed with late-onset CPSD confirmed by detection of pathogenic mutation(s), and/or decreased (\<20% of control) CPS enzyme activity in liver OR
  • Diagnosed with late-onset OTCD by detection of pathogenic OTC mutation, OR decreased (\<20% of control) OTC enzyme activity in liver OR elevated urinary orotate (greater than 20 µM/mM) following allopurinol loading with the absence of argininosuccinic acid

AND: Subject or subject's first-degree relative had plasma ammonia level ≥100 μmol/L >1 week of age

OR

o An established diagnosis of PA or MMA (as follows):

  • Diagnosed with PA by semi-quantitative urine organic acid analysis, defined as the presence of elevated Methylcitric acid and normal methylmalonic acid levels and no evidence of biotin related disorders in the organic acid analysis

OR

  • Diagnosed with MMA by semi-quantitative urine organic acid analysis, defined as an elevation of methylmalonic acid and no evidence of vitamin B12 dependent disorder on plasma amino acid analysis (B12 dependency is defined by documented B12 responsiveness)

AND: Subject or subject's first-degree relative had plasma ammonia level at any time ≥100 μmol/L

  • 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
  • If post-menarcheal must have a negative pregnancy test prior to administration of study drug at each episode
  • Signed informed consent by the subject or the subject's legally acceptable representative

Exclusion criteria

Exclusion Criteria

  • Administration of NCG within 7 days of participation in the study
  • Use of any other investigational drug, biologic, or therapy
  • Planned participation in any other clinical trial
  • Diagnosis of any medical condition causing hyperammonemia which is not PA/MMA, CPSD or OTCD. Other urea cycle disorders will be excluded from this study
  • Any clinical or laboratory abnormality or medical condition that, at the discretion of the investigator, may put the subject at additional risk by participating in this study
  • Has had a liver transplant
  • Is not expected to be compliant with this study in terms of returning to the site for subsequent episodes of hyperammonemia crises
  • Is pregnant
04

Study design

Phase
Phase 2
Primary purpose
Treatment
Allocation
Randomized
Intervention model
Parallel assignment
Masking
Quadruple (Participant, Care provider, Investigator, Outcomes assessor)
Enrollment
35 participants (actual)

Study arms

  • Experimental
    Active Comparator

    Parallel Trial Comparing NCG + Standard of Care Treatment

    Drug: Carbaglu

  • Active comparator
    Placebo Comparator

    Placebo and Standard of Care Therapy

    Drug: Placebo

Interventions

  • DrugCarbaglu

    Carbaglu Chemical Composition: N-carbamoyl-L-glutamic acid (NCG) The daily dose will be 150 mg/kg/ day or 3.3 g/m2/day for patients \>15 kg and will be administered for 7 days or until discharge, whichever is sooner. 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.

    Also known as: Carglumic Acid

  • DrugPlacebo

    Placebo that looks/tastes the same as NCG and is administered on the same schedule as the NCG intervention

05

What researchers measure

Primary outcomes

  1. Time to the Primary Outcome (Earlier of Ammonia <50 µmol/L or Hospital Discharge)

    The composite primary intention to treat (ITT) outcome of the earlier of time to reach an ammonia level of ≤50 µmol/L or hospital discharge. Data presented as a hazard ratio based on the time to reach an ammonia level of ≤50 µmol/L. The outcome measure was a survival analysis based on time to reach the earlier of an ammonia level of ≤50 µmol/L or time to discharge, which was considered to be a point where the patient was no longer at risk of neurological injury from ammonia. The outcome of survival analysis was a hazard ratio reflecting the ratio of probabilities in each group (drug vs placebo) of reaching the earlier of an ammonia level of ≤50 µmol/L or discharge. We measured multiple post-treatment ammonia levels at uncontrolled times during an episode, so it is difficult to compute a meaningful average that would not be biased by the frequency and timing of ammonia testing during episodes.

    Time frame: Average of all measurements of hyperammonemia, for up to 7 days

06

Results

Posted Feb 15, 2021

Participant flow

Participant flow — Overall Study
MilestoneEpisodes of N-CarbamylglutamateEpisodes of Placebo
Started2423
Completed2423
Not completed00

Outcome measures

PrimaryTime to the Primary Outcome (Earlier of Ammonia <50 µmol/L or Hospital Discharge)

The composite primary intention to treat (ITT) outcome of the earlier of time to reach an ammonia level of ≤50 µmol/L or hospital discharge. Data presented as a hazard ratio based on the time to reach an ammonia level of ≤50 µmol/L. The outcome measure was a survival analysis based on time to reach the earlier of an ammonia level of ≤50 µmol/L or time to discharge, which was considered to be a point where the patient was no longer at risk of neurological injury from ammonia. The outcome of survival analysis was a hazard ratio reflecting the ratio of probabilities in each group (drug vs placebo) of reaching the earlier of an ammonia level of ≤50 µmol/L or discharge. We measured multiple post-treatment ammonia levels at uncontrolled times during an episode, so it is difficult to compute a meaningful average that would not be biased by the frequency and timing of ammonia testing during episodes.

Time frame:
Average of all measurements of hyperammonemia, for up to 7 days
Reported as:
Number · Hazard Ratio
Time to the Primary Outcome (Earlier of Ammonia <50 µmol/L or Hospital Discharge)
Hazard RatioPA/MMA EpisodesCPS1D/OTCD Episodes
Time to the Primary Outcome (Earlier of Ammonia <50 µmol/L or Hospital Discharge)1.37 (0.88 to 2.13)0.79 (0.22 to 2.81)

Adverse events

Collected over During each hospitalization, once per day, up to 7 days.. Non-serious events are listed at a 0% frequency threshold.

Adverse event summary by group
GroupDeathsSeriousOther
Placebo10/24 (41.7%)6/24 (25%)9/24 (37.5%)
N-carbamylglutamate (NCG)14/25 (56%)8/25 (32%)11/25 (44%)
Most frequent serious events
Most frequent serious events
EventPlaceboN-carbamylglutamate (NCG)
Gastrointestinal DisordersGastrointestinal disorders4/245/25
Infections and InfestationsInfections and infestations2/244/25
Nervous SystemNervous system disorders0/243/25
InjuryInjury, poisoning and procedural complications1/241/25
Metabolic and NutritionalMetabolism and nutrition disorders1/241/25
RespiratoryRespiratory, thoracic and mediastinal disorders0/241/25
Most frequent other events
Showing 10 of 13
Most frequent other events
EventPlaceboN-carbamylglutamate (NCG)
MetabolismMetabolism and nutrition disorders4/246/25
GastrointestinalGastrointestinal disorders4/244/25
Blood/LymphaticBlood and lymphatic system disorders3/244/25
Nervous SystemNervous system disorders2/244/25
GeneralGeneral disorders3/241/25
InfectionsInfections and infestations3/241/25
InvestigationsInvestigations0/243/25
CardiacCardiac disorders1/241/25
Injury/Procedure ComplicationsInjury, poisoning and procedural complications1/241/25
Product IssuesProduct Issues1/240/25

Baseline characteristics

65 participants were eligible based on diagnosis. There were 35 individual participants enrolled due to a hyperammonemia episode. 24 individuals had episodes where they were randomized to the NCG arm, and 23 had episodes where they were randomized to the placebo arm. 13 participants had multiple randomizations to both arms throughout the study, while 22 participants only had a single randomization to either placebo of NCG. 35 unique participants were randomized providing 106 randomized episodes.

Age, Customized
Age, Customized(Episodes)Episodes of N-carbamylglutamate (NCG)Episodes of PlaceboTotal
0 - <5 years101626
5 - <12 years272249
12 - <18 years145
18+ years141226
Sex: Female, Male
Sex: Female, Male(Episodes)Episodes of N-carbamylglutamate (NCG)Episodes of PlaceboTotal
Female333467
Male192039
Ethnicity (NIH/OMB)
Ethnicity (NIH/OMB)(Episodes)Episodes of N-carbamylglutamate (NCG)Episodes of PlaceboTotal
Hispanic or Latino131730
Not Hispanic or Latino393675
Unknown or Not Reported011
Race (NIH/OMB)
Race (NIH/OMB)(Episodes)Episodes of N-carbamylglutamate (NCG)Episodes of PlaceboTotal
American Indian or Alaska Native000
Asian211940
Native Hawaiian or Other Pacific Islander011
Black or African American111122
White171936
More than one race235
Unknown or Not Reported112
07

Study locations

9 sites
  • University of California Los Angeles
    Los Angeles, California 90095, United States
  • Lucile Packard Children's Hospital at Stanford
    Palo Alto, California 94304, United States
  • The Children's Hospital of Colorado
    Aurora, Colorado 80045, United States
  • Children's National Medical Center
    Washington, District of Columbia 20010, United States
  • Children's Hospital Boston
    Boston, Massachusetts 02115, United States
  • Mount Sinai School of Medicine
    New York, New York 10029, United States
  • University Hospitals Cleveland Medical Center
    Cleveland, Ohio 44106, United States
  • The Children's Hospital of Philadelphia (CHOP)
    Philadelphia, Pennsylvania 19104, United States
  • University of Pittsburgh
    Pittsburgh, Pennsylvania 15224, United States
08

References and documents

Publications

  • Amari S, Shahrook S, Namba F, Ota E, Mori R. Branched-chain amino acid supplementation for improving growth and development in term and preterm neonates. Cochrane Database Syst Rev. 2020 Oct 2;10(10):CD012273. doi: 10.1002/14651858.CD012273.pub2. PubMed 33006765 ↗

Study documents

  • Protocol and statistical analysis plan · May 1, 2020

Documents are hosted by the registry — open the source record to download them.

Individual participant data

Plan to share: No — This is a blinded study, the individual participant data will not be shared

09

Registry details

Key details

Study ID
NCT01599286
Lead sponsor
Mendel Tuchman
Collaborators
Children's National Research Institute, Boston Children's Hospital, University Hospitals Cleveland Medical Center, University of California, Los Angeles, Children's Hospital of Philadelphia, Stanford University, Icahn School of Medicine at Mount Sinai, University of Pittsburgh, Children's Hospital Colorado
Responsible party
Mendel Tuchman (Scientific Director, Children's Research Institute, Children's National Research Institute) — Sponsor-investigator
First posted
May 16, 2012
Start date
Sep 1, 2012
Primary completion
Apr 30, 2019
Completion
Apr 30, 2020
Results posted
Feb 15, 2021
Last update
Feb 15, 2021

Study contacts

Mendel Tuchman, MD
principal investigator · Children's National Research Institute

Oversight

Data monitoring committee
Yes
View the source record on ClinicalTrials.gov ↗

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This study is completed, as verified in Jan 2021. You cannot join it, but the record below documents what was studied.

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