Disease Directory Methylmalonic Acidemia
Metabolic

Methylmalonic Acidemia

Also known as: MMA, methylmalonyl-CoA mutase deficiency, MUT deficiency, cobalamin metabolism defect

Prevalence

1-9 per 100,000 (Orphanet)

Onset

Neonatal, Infantile

Type

Autosomal recessive genetic

Gene

MMUT, MMAA, MMAB, MMADHC

About Methylmalonic Acidemia

Methylmalonic acidemia (MMA) is a group of inherited metabolic disorders caused by inability to metabolize certain amino acids and odd-chain fatty acids, resulting in accumulation of methylmalonic acid. The most common form involves deficiency of methylmalonyl-CoA mutase (MUT). Patients experience recurrent metabolic crises with lethargy and vomiting, chronic kidney disease, and neurological complications. Some forms respond to vitamin B12 (cobalamin), while mut0 forms do not.

Common Clinical Features

Metabolic crisis Hyperammonemia Chronic kidney disease Anemia Pancreatitis Developmental delay Movement disorder

Clinical Trial Eligibility Tips

What to know before applying to Methylmalonic Acidemia trials.

Vitamin B12 (cobalamin) responsiveness testing distinguishes responsive forms from mut0 — trial eligibility often separates these groups

Estimated GFR (eGFR) is a primary eligibility criterion — significant renal impairment may exclude patients from certain trials

Urinary and plasma methylmalonic acid levels are the primary biomarkers; document baseline values carefully

Liver-kidney transplant recipients may be eligible for quality-of-life or long-term outcome studies

Patient Resources

Patient Organization

Organic Acidemia Association

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Orphanet

European reference resource for rare diseases (ORPHA:26)

View on Orphanet ↗

NORD

National Organization for Rare Disorders

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Find recruiting Methylmalonic Acidemia trials

Search 500,000+ studies from ClinicalTrials.gov, filtered for Methylmalonic Acidemia. Updated daily.

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