ORPHA:365
Glycogen storage disease due to acid maltase deficiency
Also known as: Alpha-1,4-glucosidase acid deficiency · GSD due to acid maltase deficiency · GSD type 2 · GSD type II · Glycogen storage disease type 2 · Glycogen storage disease type II · Glycogenosis due to acid maltase deficiency · Glycogenosis type 2 · Glycogenosis type II · Pompe disease
Clinical definition (Orphanet)
A rare lysosomal storage disease characterized by lysosomal accumulation of glycogen particularly in skeletal, cardiac, and respiratory muscles, as well as the liver and nervous system, due to acid maltase deficiency. The clinical spectrum comprises -onset disease with severe hypertrophic , generalized muscle weakness, poor feeding and , and respiratory insufficiency, and late-onset disease manifesting before or after twelve months of age without , with proximal muscle weakness and respiratory insufficiency.
How rare: How common this is has not been clearly measured.
Is anyone studying this?
7,537
7,537 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=183) is 38.
7,537 papers since the earliest indexed year in this search — median last-10-year count for a rare disease in this dataset is 38 (publications denominator n=183).
4,235 in the last 10 years · low confidence
Is a treatment being tested?
92
trials for this specific condition
92 interventional trials matched this specific condition name; 13 currently recruiting in our sample.
Data as of 26 July 2026
92 interventional trials — more than 59.2% of diseases in the trials denominator have none at all (151 of 255; this disease is at the 96.3th percentile).
low confidence · 96.3th percentile (trials denominator)
Do we know what causes it?
Yes — we know a specific gene responsible (GAA).
GenCC classification: Definitive.
Who's working on it?
1,445
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.
- 01Schoser B15 papers · 2026
Department of Neurology, Friedrich-Baur-Institute, Ludwig-Maximilians-University, Munich, Germany.
Papers in Europe PMC - 02van der Ploeg AT13 papers · 2026
Erasmus MC University Medical Center, Rotterdam, Netherlands.
Papers in Europe PMC - 03Kishnani PS11 papers · 2026
Division of Medical Genetics, Department of Pediatrics, Duke University Medical Center, Durham, NC 27710, USA.
Papers in Europe PMC - 04Laforêt P9 papers · 2026
Raymond Poincaré Teaching Hospital, APHP, Garches, France.
Papers in Europe PMC - 05
- 06Díaz-Manera J7 papers · 2026
The John Walton Muscular Dystrophy Research Centre, Newcastle University Translational and Clinical Research Institute, Newcastle Upon Tyne, UK.
Papers in Europe PMC - 07Domínguez-González C7 papers · 2026
Neuromuscular disorders Unit, Neurology department, 12 de Octubre Hospital, Madrid, Spain.
Papers in Europe PMC - 08Parenti G7 papers · 2026
Telethon Institute of Genetics and Medicine (TIGEM), Via Campi Flegrei 34, Pozzuoli, Italy. parenti@tigem.it.
Papers in Europe PMC - 09Byrne BJ6 papers · 2026
Powell Gene Therapy Center, University of Florida, Gainesville, USA.
Papers in Europe PMC - 10Li D6 papers · 2026
Department of Pediatric Neurology, Tianjin Children's Hospital, Tianjin University Children's Hospital, Tianjin, China.
Papers in Europe PMC
Recruiting interventional trials
Trials testing a treatment from the matched ClinicalTrials.gov set
92 interventional trials matched after quoted-phrase search and title/condition post-filter.
- NCT07072676·The Use of Assistive Gait Devices Can Reduce the Risk of Falls in Patients With Neuromuscular Diseases Following a Training Period.
- NCT04532047·PEARL (PrEnAtal Enzyme Replacement Therapy for Lysosomal Storage Disorders)
- NCT07123155·Study of S-606001 as an Add-on to Enzyme Replacement Therapy (ERT) in Participants With Late-onset Pompe Disease (LOPD)
- NCT06666413·China Post-approval Commitment (PAC) Study of Avalglucosidase Alfa in Participants With IOPD
- NCT07282847·A Study to Evaluate Safety, Tolerability, and Efficacy of AB-1009 Gene Therapy (GAA Gene) in Adult Participants With Late-Onset Pompe Disease (PROGRESS-GT LOPD)
- NCT04808505·A Study to Evaluate the Safety, Efficacy, PK, PD and Immunogenicity of Cipaglucosidase Alfa/Miglustat in IOPD Subjects Aged 0 to <18
- NCT06391736·Evaluation of the Safety and Efficacy of Late-onset Pompe Disease Gene Therapy Drug
- NCT07136844·Gait Analysis Parameter and Upper Limb Evaluation in Adult Patients With Neurological or Metabolic Pathology
- NCT06575829·Treatment Frequency Reduction in Pompe Disease
- NCT07478172·Effects of Whole-body Electrical Muscle Stimulation Exercise on Adults With Neuromuscular Disease
- NCT06833489·Transcriptomic Analysis to Put an End to Misdiagnosis in Patients With Rare Muscle Diseases
- NCT07354724·A Study to Evaluate the Safety, Pharmacokinetics, and Pharmacodynamics of DNL952 in Adult Participants With Late-Onset Pompe Disease
- NCT06178432·Evaluation of the Safety, Tolerability and Efficacy of Gene Therapy Drug for Late Onset Pompe Disease (LOPD)
Observational and natural-history studies
67 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.
Recruiting or not-yet-recruiting
- NCT05734521·Avalglucosidase Alfa Pregnancy Study
- NCT03564561·Natural History of Pompe Disease
- NCT01665326·Determination of CRIM Status and Longitudinal Follow-up of Individuals With Pompe Disease
- NCT07664930·Phrenic Nerve and Diaphragm Electrophysiology in Pompe Disease
- NCT06121011·A Global Prospective Observational Registry of Patients With Pompe Disease
- NCT04639336·Cognitive and Neurological Pathologies in Pompe Disease
- NCT06605612·Development and Validation of the FBIndex to Determine the Risk of Falls for Patients With Neuromuscular Disorders
- NCT00567073·Pompe Pregnancy Sub-Registry
- NCT02399748·A Long-term Study for the Outcome of Pompe Disease
- NCT00231400·Pompe Disease Registry Protocol
- NCT06539169·FLOWER: Following Longitudinal Outcomes With Epidemiology for Rare Diseases
- NCT05017402·Higher Dose of Alglucosidase Alpha for Pompe Disease
- NCT05619900·Registry of Patients Diagnosed With Lysosomal Storage Diseases
Where to find support
We do not yet link condition-specific patient organisations. These umbrella groups support undiagnosed and ultra-rare families:
India — NPRD
Last verified 2026-07-26Directly listed under NPRD Group 3.
Group 3 — high-cost / lifelong therapy with careful selection
Up to ₹50 lakh per patient
Financial support at notified Centres of Excellence is the figure commonly cited in recent MoHFW/PIB statements. Many Group 3 patients also use the MoHFW voluntary-contribution / crowdfunding portal.
Eligibility and patient selection rules change. Verify with a CoE; the crowdfunding portal is a separate mechanism from CoE funding. Verify
Centres of Excellence (15)
- All India Institute of Medical Sciences (AIIMS) — New Delhi, Delhi
- Maulana Azad Medical College — New Delhi, Delhi
- Sanjay Gandhi Post Graduate Institute of Medical Sciences — Lucknow, Uttar Pradesh
- Post Graduate Institute of Medical Education and Research (PGIMER) — Chandigarh, Chandigarh
- Centre for DNA Fingerprinting & Diagnostics with Nizam’s Institute of Medical Sciences — Hyderabad, Telangana
- King Edward Memorial Hospital — Mumbai, Maharashtra
- Institute of Post-Graduate Medical Education and Research (IPGMER) — Kolkata, West Bengal
- Centre for Human Genetics with Indira Gandhi Hospital — Bengaluru, Karnataka
- Institute of Child Health and Hospital for Children (ICH & HC) — Chennai, Tamil Nadu
- All India Institute of Medical Sciences (AIIMS) — Jodhpur, Rajasthan
- Sree Avittam Thirunal Hospital (SAT), Government Medical College — Thiruvananthapuram, Kerala
- All India Institute of Medical Sciences (AIIMS) — Bhopal, Madhya Pradesh
- Regional Institute of Medical Sciences (RIMS) — Imphal, Manipur
- All India Institute of Medical Sciences (AIIMS) — Patna, Bihar
- Assam Medical College & Hospital — Dibrugarh, Assam
Voluntary contributions / crowdfunding (separate from CoE funding): https://rarediseases.mohfw.gov.in/
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 below but are not added to the query string.
"Glycogen storage disease due to acid maltase deficiency" OR "Alpha-1,4-glucosidase acid deficiency" OR "GSD due to acid maltase deficiency" OR "GSD type 2" OR "GSD type II" OR "Glycogen storage disease type 2" OR "Glycogen storage disease type II" OR "Glycogenosis due to acid maltase deficiency" OR "Glycogenosis type 2" OR "Glycogenosis type II" OR "Pompe disease" OR "GAA glycogen storage disease" OR "acid maltase deficiency" OR "generalised glycogenosis" OR "glycogen storage disease II" OR "glycogen storage disease caused by mutation in GAA"
ClinicalTrials.gov query (quoted phrases + MeSH via query.cond, plus recall-expansion terms when used):
"Glycogen storage disease due to acid maltase deficiency" OR "Alpha-1,4-glucosidase acid deficiency" OR "GSD due to acid maltase deficiency" OR "GSD type 2" OR "GSD type II" OR "Glycogen storage disease type 2" OR "Glycogen storage disease type II" OR "Glycogenosis due to acid maltase deficiency" OR "Glycogenosis type 2" OR "Glycogenosis type II" OR "Pompe disease" OR "GAA glycogen storage disease" OR "acid maltase deficiency" OR "generalised glycogenosis" OR "glycogen storage disease II" OR "GAA" OR "disorder of glycogen metabolism" OR "lysosomal glycogen storage disease" OR "lysosomal storage 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: 92 interventional · 67 observational · 4 expanded access. Only interventional studies enter the trial headline.
Cross-references (from Mondo): UMLS:C0017921 NCIT:C84734
Query health: ok — strategies attempted: phrase, recall-expansion; with hits: phrase, recall-expansion
Run this search on ClinicalTrials.gov
Confidence reasoning
- Preferred label is multi-word and distinctive
- No synonyms dropped by stoplist
- No label/synonym collisions with other diseases in this corpus
- Publication count (7537) is extremely high with unknown/missing prevalence — treat as possible over-matching, not proven research intensity