ORPHA:93160
Hypocalcemic vitamin D-resistant rickets
Also known as: HVDRR · Hereditary vitamin D-resistant rickets · VDDR II · VDRR II · Vitamin D-dependent rickets type II · Vitamin D-resistant rickets type II
Query health: suspect — Only one of 2 strategies returned hits (phrase).
Publications
615
82th percentile
Trials
0
Interventional, condition-specific
Researchers
859
Distinct authors in sample
Gene link
—
Readiness
2/6
Stages with a signal
Clinical definition (Orphanet)
A rare genetic, disorder of vitamin D metabolism characterized by hypocalcemia, severe rickets and in many cases alopecia.
How rare: How common this is has not been clearly measured.
Cross-references
Joined from Mondo / Orphanet. MeSH labels may enter searches; UMLS / OMIM / NCIT are stored for reference.
- MONDO:0019642
- UMLS:C3536983
- NCIT:C131077
Additional Mondo synonyms (9)
VDDR2 · hereditary 1,25 dihydroxyvitamin D-resistant rickets with abnormal Vitamin D receptor · hereditary vitamin D-resistant rickets · hypocalcemic vitamin D-resistant rickets · vitamin D dependent rickets 2 · vitamin D receptor deficiency · vitamin D-dependent rickets type II · vitamin D-dependent rickets, type 2 · vitamin D-resistant rickets type II
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.”
2/6 stages with a signal
No specific-condition interventional trial, but broader-category trials exist — discuss eligibility with a clinician.
- Gene identifiedNot found
No GenCC disease–gene assertion in this build
- LiteraturePresent
615 matched papers (251 in last 10 years) Source
- Phenotype characterisedNot checked
Not yet enriched from Monarch / HPO
- Animal modelNot checked
Not yet enriched from Monarch / Alliance
- Orphan designationNot checked
FDA/EMA orphan-drug designation not enriched yet
- Interventional trialPartial
None under the specific name; 26 for broader category rickets
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?
Not yet — the cause hasn't been pinned down in GenCC.
No strong gene–disease assertion joined for this Orphanet entity.
Phenotypes (Monarch / HPO)
Not enriched in this build — Monarch phenotype joins were not run for this record.
Animal models (Monarch / Alliance)
Not enriched in this build.
Literature
Is anyone studying this?
615
615 papers have been published on this condition. That is a real research literature — still far smaller than common diseases (breast cancer: over 700,000 papers). Median papers in the last 10 years for a rare disease in this dataset (publications denominator n=5449) is 41.
615 papers since the earliest indexed year in this search — median last-10-year count for a rare disease in this dataset is 41 (publications denominator n=5449).
251 in the last 10 years · high confidence · 82th percentile (publications denominator)
Phrase hits: 615 · MeSH hits: 0
Who's working on it?
859
Distinct author names in 200 sampled papers — named people below.
Who's working on it?
No interventional trial matched this name; these authors publish on it in the sampled literature — a practical starting point for contact.
- 01Feldman D14 papers · 2014
Department of Medicine, Stanford University , Stanford, CA, USA.
Papers in Europe PMC - 02Malloy PJ13 papers · 2014
S025 Division of Endocrinology, Gerontology, and Metabolism, Stanford University School of Medicine, 300 Pasteur Drive, Stanford, California 94305-5103, USA. pjmalloy@stanford.edu
Papers in Europe PMC - 03Stich B10 papers · 2026
Institute of Quantitative Genetics and Genomics of Plants, Heinrich Heine University Duesseldorf, Duesseldorf, Germany.
Papers in Europe PMC - 04Wang J8 papers · 2014
Department of Medicine, Stanford University School of Medicine, Stanford, CA 94305, USA.
Papers in Europe PMC - 05Kongsbak-Wismann M6 papers · 2025
The LEO Foundation Skin Immunology Research Center, Department of Immunology and Microbiology, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark.
Papers in Europe PMC - 06van Inghelandt D6 papers · 2026
Institute for Breeding Research on Agricultural Crops, Julius Kühn Institute (JKI) - Federal Research Centre for Cultivated Plants, Sanitz, 18190, Germany.
Papers in Europe PMC - 07Gao Y5 papers · 2026
State Key Laboratory of Reproductive Regulation and Breeding of Grassland Livestock, School of Life Sciences, Inner Mongolia University, 235 West University Road, Hohhot, 010021, China.
Papers in Europe PMC - 08Kitanaka S5 papers · 2020
Department of Pediatrics, Graduate School of Medicine, The University of Tokyo, Japan.
Papers in Europe PMC - 09Shrestha A5 papers · 2026
Institute for Quantitative Genetics and Genomics of Plants, Biology Department, Heinrich Heine University, Dusseldorf, Germany.
Papers in Europe PMC - 10Tiosano D5 papers · 2021
Division of Pediatric Endocrinology, Ruth Children's Hospital, Rambam Health Care Campus, Haifa, Israel; Bruce Rappaport Faculty of Medicine, The Technion, Haifa, Israel. Electronic address: d_tiosano@rambam.health.gov.il.
Papers in Europe PMC
Clinical research
Is a treatment being tested?
0
interventional trials for this specific condition
No interventional trial testing a treatment matched this specific condition name on ClinicalTrials.gov (observational studies and pan-disease registries are listed separately when present). 26 trials are registered for rickets, the broader category — shown separately because they may or may not enrol this specific subtype.
Data as of 27 July 2026
No matched interventional trials. This is true for 73% of diseases in the trials denominator (5114 of 7003). Here are the researchers publishing on it.
high confidence · 36.5th percentile (trials denominator)
Recruiting interventional trials
From the matched ClinicalTrials.gov set
No interventional trial testing a treatment was found for this specific condition name on ClinicalTrials.gov.
26 interventional trials matched rickets, the broader category — listed below. Those studies are not counted in the condition-specific total.
Broader category: rickets
26
Interventional trials for the parent category, exclusive of NCT IDs already counted above. Eligibility for this subtype is not guaranteed.
Worth raising with a clinician. How we count trials.
Recruiting under the broader category
- NCT06462547·RECRUITING·ADAPT Study: Long-term Safety Study of INZ-701 in Patients With ENPP1 Deficiency and ABCC6 Deficiency
Conditions: Gene Mutations · Pseudoxanthoma Elasticum · Arterial Calcification · Ectonucleotide Pyrophosphatase/phosphodiesterase1 Deficiency·Matched via name phrase
- NCT05734196·RECRUITING·The ENERGY Study: Evaluation of Safety and Tolerability of INZ-701 in Infants With ENPP1 Deficiency or ABCC6 Deficiency
Conditions: Ectonucleotide Pyrophosphatase/phosphodiesterase1 Deficiency · Autosomal Recessive Hypophosphatemic Rickets · Generalized Arterial Calcification of Infancy · ATP-Binding Cassette Subfamily C Member 6 Deficiency·Matched via name phrase
- NCT03771105·RECRUITING·The Impact of Phosphate Metabolism on Healthy Aging
Conditions: Hypophosphatemia · Rickets · Hypercalciuria · XLH·Matched via name phrase
- NCT07473973·RECRUITING·ENERGY 2: Evaluation of the Efficacy and Safety of INZ-701 in Infants With ENPP1 Deficiency
Conditions: Ectonucleotide Pyrophosphatase/phosphodiesterase1 Deficiency · Autosomal Recessive Hypophosphatemic Rickets · Generalized Arterial Calcification of Infancy 1·Matched via name phrase
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 2026-07-26This 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.
"Hypocalcemic vitamin D-resistant rickets" OR "HVDRR" OR "Hereditary vitamin D-resistant rickets" OR "VDDR II" OR "VDRR II" OR "Vitamin D-dependent rickets type II" OR "Vitamin D-resistant rickets type II" OR "VDDR2" OR "hereditary 1,25 dihydroxyvitamin D-resistant rickets with abnormal Vitamin D receptor" OR "vitamin D dependent rickets 2" OR "vitamin D receptor deficiency" OR "vitamin D-dependent rickets, type 2"
ClinicalTrials.gov query (quoted phrases + MeSH via query.cond, plus recall-expansion terms when used):
"Hypocalcemic vitamin D-resistant rickets" OR "HVDRR" OR "Hereditary vitamin D-resistant rickets" OR "VDDR II" OR "VDRR II" OR "Vitamin D-dependent rickets type II" OR "Vitamin D-resistant rickets type II" OR "VDDR2" OR "hereditary 1,25 dihydroxyvitamin D-resistant rickets with abnormal Vitamin D receptor" OR "vitamin D dependent rickets 2" OR "vitamin D receptor deficiency" OR "vitamin D-dependent rickets, type 2" OR "hypocalcemic rickets" OR "vitamin D-dependent rickets" OR "disorders of vitamin D metabolism"
Recall-expansion terms: hypocalcemic rickets, vitamin D-dependent rickets, disorders of vitamin D metabolism
Study-type breakdown: 0 interventional · 0 observational · 0 expanded access. Only interventional studies enter the trial headline.
Parent-category trials query:
"rickets"
Query health: suspect — strategies attempted: phrase, recall-expansion; with hits: phrase
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
Ingested 2026-07-27T04:07:46.595Z