ORPHA:158
Systemic primary carnitine deficiency
Also known as: CDSP · CUD · Carnitine transporter defect · Carnitine uptake deficiency · Deficiency of plasma-membrane carnitine transporter · SPCD
Publications
5,405
92th percentile
Trials
6
Interventional, condition-specific
Researchers
1,202
Distinct authors in sample
Gene link
SLC22A5
Definitive
Readiness
6/6
Stages with a signal
Clinical definition (Orphanet)
A rare disorder of carnitine cycle and carnitine transport that is characterized classically by early childhood onset often with weakness and , and recurrent hypoglycemic hypoketotic and/or coma.
How rare: 1-9 / 100 000 — about one to nine people per hundred thousand.
Cross-references
Joined from Mondo / Orphanet. MeSH labels may enter searches; UMLS / OMIM / NCIT are stored for reference.
- MONDO:0008919
- MeSH:C536778
- OMIM:212140
- UMLS:C0342788
- NCIT:C98864
Additional Mondo synonyms (8)
Carnitine deficiency · carnitine transporter deficiency · carnitine uptake defect · cud · deficiency of plasma-membrane carnitine transporter · primary carnitine deficiency · renal carnitine transport defect · systemic primary carnitine deficiency disease
Research stages
Trial readiness signals
Where this condition sits on an open-data research pipeline — not how close a treatment is, and not medical advice. Empty stages often mean “not in these databases under this Mondo ID,” not “impossible.”
6/6 stages with a signal
An interventional trial matched this condition name on ClinicalTrials.gov — see trials below.
- Gene identifiedPresent
Definitive — SLC22A5
- LiteraturePresent
5,405 matched papers (2,889 in last 10 years) Source
- Phenotype characterisedPresent
44 HPO annotations (e.g. Myopathy; Hepatomegaly; Endocardial fibroelastosis) Source
- Animal modelPresent
8 genotype models (Mus musculus) Source
- Orphan designationPresent
3 FDA designations (1 FDA orphan-indication approval) — e.g. Levocarnitine Source
- Interventional trialPresent
6 matched on ClinicalTrials.gov (1 recruiting in sample)
Biology
Genes and phenotypes
Gene–disease validity from GenCC, plus phenotypes and animal models joined from Monarch Initiative via Mondo ID — not a clinical diagnosis aid.
Do we know what causes it?
Yes — we know a specific gene responsible (SLC22A5).
GenCC classification: Definitive.
Phenotypes (Monarch / HPO)
44
Associated phenotypes · MONDO:0008919
- Myopathy
- Hepatomegaly
- Endocardial fibroelastosis
- Reduced muscle carnitine level
- Recurrent hypoglycemia
Showing 5 of 44 — open Monarch for the full list.
Animal models (Monarch / Alliance)
8
Model associations linked to this Mondo ID
- Slc22a5jvs/Slc22a5jvs [background:] C3.OH-H2o2 Slc22a5jvs·MGI:3032447·Mus musculus
Monarch fetch 2026-07-29
Therapies
Designations, candidates, and chemicals
FDA OOPD and EMA orphan designations, Open Targets clinical candidates, and CTD chemical associations via MyDisease.info. These never change the interventional-trial headline.
Orphan designation (FDA · EMA)
3
Designations · 1 with FDA orphan-indication approval
- FDA LevocarnitineEnd stage renal disease Carnitine Deficiency · 1986-11-24 · Not FDA Approved for Orphan Indication
- FDA Levocarnitine (Carnitor)End stage renal disease Carnitine Deficiency · 1988-09-06
- FDA Levocarnitine (Carnitor)Carnitine Deficiency · 1984-02-28
Sources: FDA OOPD · EMA orphan designations
CTD chemicals (MyDisease.info)
2 associated chemicals · 6 pathways. Therapeutic evidence is listed first when present — not a treatment recommendation.
- Pivampicillin · marker/mechanism
- Valproic Acid · marker/mechanism
Pathways: Choline metabolism in cancer; Transmembrane transport of small molecules; Transport of glucose and other sugars, bile salts and organic acids, metal ions and amine compounds; SLC-mediated transmembrane transport; Organic cation transport; Organic cation/anion/zwitterion transport
Literature
Is anyone studying this?
5,405
5,405 papers — among the better-studied rare conditions, though still a fraction of common-disease literature (breast cancer: over 700,000). Median papers in the last 10 years for a rare disease in this dataset (publications denominator n=3967) is 59.
5,405 papers since the earliest indexed year in this search — median last-10-year count for a rare disease in this dataset is 59 (publications denominator n=3967).
2,889 in the last 10 years · medium confidence · 92th percentile (publications denominator)
Phrase hits: 3,810 · MeSH hits: 0
Who's working on it?
1,202
Distinct author names in 200 sampled papers — named people below.
Who's working on it?
People publishing on this condition (sampled Europe PMC records). Affiliation is the most recent found in that sample.
- 01Lin Y12 papers · 2026
Department of Genetics and Metabolism, Children's Hospital of Zhejiang University School of Medicine, National Clinical Research Center for Child Health, Hangzhou, China; Neonatal Disease Screening Center, Quanzhou Maternity and Children's Hospital, Quanzhou, China.
Papers in Europe PMC - 02Lin W10 papers · 2026
Neonatal Disease Screening Center, Quanzhou Maternity and Children's Hospital, 700 Fengze Street, Quanzhou, 362000, Fujian Province, China.
Papers in Europe PMC - 03Zhang H9 papers · 2026
Neonatal Disease Screening Center, The Maternal and Child Health Hospital of Shaoyang City, Shaoyang, China.
Papers in Europe PMC - 04Zheng Z9 papers · 2025
Neonatal Disease Screening Center, Quanzhou Maternity and Children's Hospital, 700 Fengze Street, Quanzhou, Fujian Province 362000, China.
Papers in Europe PMC - 05Chen Y7 papers · 2026
Neonatal Screening Center, Fujian Maternity and Child Health Hospital, Affiliated Hospital of Fujian Medical University, Fuzhou, China.
Papers in Europe PMC - 06Han L6 papers · 2025
Department of Pediatric Endocrinology and Genetic Metabolism, Shanghai Institute for Pediatric Research, Xinhua Hospital, Shanghai Jiaotong University School of Medicine, Shanghai 200092, China.
Papers in Europe PMC - 07Li Y6 papers · 2026
Department of Pancreatic Surgery, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430022, China.
Papers in Europe PMC - 08Peng W6 papers · 2024
Neonatal Disease Screening Center, Quanzhou Maternity and Children's Hospital, 700 Fengze Street, Quanzhou, 362000, Fujian Province, China.
Papers in Europe PMC - 09Zhang W6 papers · 2024
Department of Neonatal Intensive Care Unit, Quanzhou Maternity and Children's Hospital, 700 Fengze Street, Quanzhou, 362000, Fujian Province, China.
Papers in Europe PMC - 10Chen J5 papers · 2026
Department of Neurology, Affiliated Hospital of Guangdong Medical University, Zhanjiang, China.
Papers in Europe PMC
Clinical research
Is a treatment being tested?
6
interventional trials for this specific condition
6 interventional trials matched this specific condition name; 1 currently recruiting in our sample.
Data as of 11 September 2026 · last trial check 28 July 2026
6 interventional trials — more than 77.2% of diseases in the trials denominator have none at all (5501 of 7126; this disease is at the 90.1th percentile).
medium confidence · 90.1th percentile (trials denominator)
Recruiting interventional trials
From the matched ClinicalTrials.gov set
6 interventional trials matched after quoted-phrase search and title/condition post-filter.
- NCT07201714·RECRUITING·Oral Carnitine in Heart Failure Patients
Not reviewed·Conditions: Heart Failure · Carnitine Deficiency·Matched via name phrase
Observational and natural-history studies
3 observational studies match this condition. These do not test a treatment and are not counted in the interventional-trial headline, but they are genuine research: natural-history work often defines the endpoints needed for a future rare-disease trial, and families may be able to enroll.
None of the matched observational studies is currently listed as recruiting.
Other registries (secondary)
Broader net from EU CTIS, ISRCTN, and ICTRP when available — deduped against ClinicalTrials.gov IDs already counted above. Dual-model LLM relevance gates what we keep. These rows are not added to the interventional headline.
raw 2 · after dedupe 2 · already on CT.gov 0 · kept 0 · parent 0 · uncertain 2 · dropped 0 · fetched 2026-07-29
Source notes: ictrp: Error: ICTRP public search unavailable (WHO portal is SPA-only; SOAP needs partnership). Tried: https://apps.who.int/tri
No secondary-registry studies passed dual-model relevance for this condition name (after dedupe).
Uncertain / not reviewed (2)
- isrctn·ISRCTN38724906·Not yet recruiting·Plant Your Health: a randomised controlled trial comparing vegan, vegetarian and omnivorous diets in younger to middle-aged adults with overweight or obesity
skipped — LLM skipped (--skip-llm)
- isrctn·ISRCTN73427832·No longer recruiting·A clinical trial assessing the addition of continuous ketogenic diet therapy to standard chemotherapy and immunotherapy treatment for patients with advanced squamous cell lung cancer
skipped — LLM skipped (--skip-llm)
Where to find support
Condition-specific patient organisations, when Orphanet lists them, are on the disease’s Orphanet page. We also link umbrella groups that support undiagnosed and ultra-rare families.
Orphanet entry for Systemic primary carnitine deficiency — check Associations / patient organisations on that page.
India — NPRD
Last verified 2026-07-26This ORPHAcode is not on our curated NPRD list (direct or Mondo-parent match). That does not decide clinical eligibility; families in India should ask a notified Centre of Excellence about current coverage.
Hand-curated for this project. ORPHAcode mappings are best-effort and may be incomplete or imprecise for umbrella categories. Parent (Mondo) matches mean the policy lists a broader category — confirm eligibility with a Centre of Excellence. Financial entitlements summarised from public policy statements and may change. This is not official government guidance.
How we counted this
Europe PMC query (preferred label + any corrected label + Orphanet and Mondo exact synonyms, stoplisted; unioned with resolved MeSH labels when available). UMLS / OMIM / NCIT cross-references are stored on the overview but are not added to the query string.
("Systemic primary carnitine deficiency" OR "Carnitine transporter defect" OR "Carnitine uptake deficiency" OR "Deficiency of plasma-membrane carnitine transporter" OR "Deficiency of the plasma-membrane carnitine transporter" OR "Carnitine deficiency" OR "carnitine transporter deficiency" OR "carnitine uptake defect" OR "primary carnitine deficiency" OR "renal carnitine transport defect" OR "systemic primary carnitine deficiency disease") OR ("SLC22A5" OR "SLC22A5 syndrome" OR "SLC22A5-related")ClinicalTrials.gov query (quoted phrases + MeSH via query.cond, plus recall-expansion terms when used):
"Systemic primary carnitine deficiency" OR "Carnitine transporter defect" OR "Carnitine uptake deficiency" OR "Deficiency of plasma-membrane carnitine transporter" OR "Deficiency of the plasma-membrane carnitine transporter" OR "Carnitine deficiency" OR "carnitine transporter deficiency" OR "carnitine uptake defect" OR "primary carnitine deficiency" OR "renal carnitine transport defect" OR "systemic primary carnitine deficiency disease"
Interventional trials matched via: phrase (mesh = registered under a MeSH descriptor no name phrase would catch; recall-expansion = gene / selected parent terms used only for trials).
Study-type breakdown: 6 interventional · 3 observational · 0 expanded access. Only interventional studies enter the trial headline.
Query health: ok — strategies attempted: phrase; with hits: phrase
Run this search on ClinicalTrials.gov
Synonyms dropped by stoplist: CDSP; CUD; SPCD
Confidence reasoning
- Preferred label is multi-word and distinctive
- 3 synonym(s) dropped by stoplist (may under-count)
- No label/synonym collisions with other diseases in this corpus
Ingested 2026-07-26T12:41:37.693Z