Last reviewed · How we verify
Rayaldee (CALCIFEDIOL)
Rayaldee works by increasing the levels of active vitamin D in the body.
Rayaldee (calcifediol) is a small molecule modality that targets sterol regulatory element-binding protein 1. Originally developed, it is now owned by Eirgen and was FDA approved in 1980 for the treatment of hypocalcemia, hypophosphatemia, renal osteodystrophy, and rickets. As an off-patent calcifediol, it is not commercially available as a generic. Key safety considerations include its long half-life of 11 days. Rayaldee is used to treat conditions related to low calcium levels in the blood.
At a glance
| Generic name | CALCIFEDIOL |
|---|---|
| Sponsor | Eirgen |
| Drug class | calcifediol |
| Target | Sterol regulatory element-binding protein 1 |
| Modality | Small molecule |
| Therapeutic area | Nephrology |
| Phase | FDA-approved |
| First approval | 1980 |
Mechanism of action
Calcifediol (25-hydroxyvitamin D3) is prohormone of the active form of vitamin D3, calcitriol (1,25-dihydroxyvitamin D3). Calcifediol is converted to calcitriol by cytochrome P450 27B1 (CYP27B1), also called 1-alpha hydroxylase, primarily in the kidney. Calcitriol binds to the vitamin receptor in target tissues and activates vitamin responsive pathways that result in increased intestinal absorption of calcium and phosphorus and reduced parathyroid hormone synthesis.
Approved indications
- Hypocalcemia
- Hypophosphatemia
- Renal osteodystrophy
- Rickets
Common side effects
- Anemia
- Nasopharyngitis
- Increased blood creatinine
- Dyspnea
- Cough
- Cardiac failure congestive
- Constipation
- Bronchitis
- Hyperkalemia
- Osteoarthritis
- Hyperuricemia
- Contusion
Key clinical trials
- Vitamin D Status in Young Medical Residents
- Evaluation of Serum TRACP-5b, BALP, and 25-Hydroxyvitamin D3 Levels in Stage III Periodontitis Patients (NA)
- Effect of Vitamin D in Diets of Preterm Infants (NA)
- Effect of Vitamin D Deficiency on the Frequency and Severity of Spinal Anesthesia-Induced Hypotension in Pregnant Women Undergoing Cesarean Section
- Exercise Training and Vitamin D Metabolism (NA)
- Vitamin D and Immune Mechanisms of Hypertension in Type 2 Diabetics
- Oral Vitamin D3 Effect on Inflammatory Biomarkers in Ulcerative Colitis Patients (NA)
- Cholecalciferol and Calcifediol Are Both Useful to Improve Vitamin D Serum Levels (NA)
Patents
| Patent | Expiry | Type |
|---|---|---|
| 8778373 | 2028-04-25 | Method of Use |
| 9408858 | 2028-04-25 | Method of Use |
| 9943530 | 2027-02-02 | Method of Use |
| 9925147 | 2028-04-25 | Formulation |
| 8207149 | 2028-04-25 | Method of Use |
| 8426391 | 2028-08-27 | Method of Use |
| 11801253 | 2030-09-07 | Formulation |
| 9498486 | 2028-04-25 | Method of Use |
Primary sources
Every claim on this page is sourced from regulatory or scientific primary sources. See our editorial policy for full methodology.
| Source | Used for |
|---|---|
| FDA label | Mechanism, indications, dosing, boxed warnings, drug interactions |
| ClinicalTrials.gov | Trial enrolment, design, endpoints, results |
| FDA Orange Book | Patents + exclusivity |
Competitive intelligence
For the full competitive landscape — auto-detected comparators, recent regulatory actions across the set, upcoming PDUFA, patent timeline, sponsor landscape:
- Rayaldee CI brief — competitive landscape report
- Rayaldee updates RSS · CI watch RSS