Page data last changed: . Chemistry registry snapshot: . Registry refreshes and identity assessments are separate from scientific content review.
The fish version of a human hormone became the drug: 32 residues, a Cys1–Cys7 ring, and higher potency than human calcitonin.
Also known as: Salmon calcitonin · sCT · Calcitonin salmon injection
Part of the Foundational & therapeutic peptides cluster
Overview
Salmon calcitonin is a 32-amino-acid peptide (C145H242N44O48S2, ≈3,434 Da) that shares the calcitonin family's N-terminal disulfide ring and C-terminal prolinamide but differs from human calcitonin at many positions. It is the form used pharmaceutically: FDA-approved for over 30 years, commonly for hypercalcaemia of malignancy and historically for postmenopausal osteoporosis. Eel and salmon calcitonins are more potent than the human hormone in cell assays.
Source & context
Biological / chemical source: Synthetic peptide with the sequence of salmon calcitonin
Primary research or clinical context: Approved therapeutic for over 30 years (FDA); used for hypercalcaemia of malignancy and, historically, postmenopausal osteoporosis
What salmon calcitonin is — and why the fish version
Calcitonin is a 32-residue hormone that lowers blood calcium by suppressing osteoclast activity and increasing renal calcium excretion. Every vertebrate makes a version; the salmon sequence, C-S-N-L-S-T-C-V-L-G-K-L-S-Q-E-L-H-K-L-Q-T-Y-P-R-T-N-T-G-S-G-T-P-NH2, keeps the family's hallmarks — a disulfide ring between cysteines 1 and 7 and a C-terminal prolinamide — but differs from human calcitonin at many mid-chain positions. That difference is the point: salmon calcitonin is the form used as a medicine because it is more potent than the human hormone. The human hormone has its own profile on this site (Calcitonin); this page covers the pharmaceutical salmon peptide.
Potency: salmon, eel and human calcitonin compared
In primary cultures of anterior pituitary cells and in osteoblast-like UMR-106 cells, repeated treatment with any calcitonin inhibited inositol phospholipid turnover; eel calcitonin and its semi-synthetic analogue [Asu1,7]eel calcitonin were always more potent than salmon calcitonin, while the efficacy of the three polypeptides was comparable (Sortino et al., Gynecological Endocrinology 1993). The ranking places the fish calcitonins above the human hormone in potency, which is why salmon calcitonin became the standard pharmaceutical form and elcatonin (the eel analogue) is used in some markets.
Clinical use
Salmon calcitonin has been approved by the FDA for over 30 years and is commonly used to treat hypercalcaemia of malignancy; a marked rise in its acquisition cost led health systems to adopt stewardship strategies to ensure appropriate use (Allison & Davis, Journal of Pharmacy Practice 2019). It also has a long history in postmenopausal osteoporosis, where the reviews in the evidence pack list it among the drug-therapy options alongside oestrogen, bisphosphonates and raloxifene (Vondracek, American Journal of Health-System Pharmacy 2010; Greenblatt, Pharmacotherapy 2005), while noting that alendronate and oestrogen were the more effective choices (Andrews, Postgraduate Medicine 1998). In nursing-home residents with osteoporosis, calcitonin appears among the treatments recorded in retrospective cohort data (Zarowitz et al., JAMDA 2015).
Analytical characterisation
Because salmon calcitonin injection contains phenol, a UV-active excipient that reacts with dithiothreitol and trypsin, peptide mapping of the drug product is difficult. A 2024 method extracted the peptide by solid-phase extraction before tryptic digestion and used ultra-high-performance liquid chromatography with high-resolution mass spectrometry to sequence the amino acids and map peptides, including side-chain modifications (Kuril et al., Journal of Pharmaceutical and Biomedical Analysis 2024). The approach is a model for verifying synthetic peptide drug products residue by residue.
Lactation and safety notes from the literature
The LactMed database notes that little information is available on clinical use during breastfeeding; calcitonin is a normal component of human milk and, as a large peptide, is unlikely to be absorbed by the infant because it is probably destroyed in the gastrointestinal tract. Calcitonin therapy is sometimes used for symptomatic postpartum osteoporosis, and there is no evidence that exogenous calcitonin decreases prolactin or lactation (LactMed, 2024 update). The registry snapshot for the search term is dominated by unrelated studies matching 'calcitonin' (for example CGRP-targeted migraine trials) and is not a meaningful footprint for this peptide.
How it relates to other peptides on this site
The calcitonin receptor is the same receptor that, combined with receptor-activity-modifying proteins, becomes the amylin receptor — which is why cagrilintide, the amylin analogue in CagriSema, is described as a dual amylin/calcitonin receptor agonist and why its designers borrowed features from salmon calcitonin. Pramlintide, amylin and the human calcitonin profile complete the family. Teriparatide and palopegteriparatide act in the opposite direction on serum calcium.
Sequence
One-letter sequence commonly cited for Calcitonin (salmon) (educational; isoforms and modifications may differ):
CSNLSTCVLGKLSQELHKLQTYPRTNTGSGTP
Residues plotted ~100° apart around an α-helix — clustering of one color reveals an amphipathic face.
Structure & chemistry
Molecular identity & reference confidence
Source-supported reference
Reference values are taken from the cited molecular record or curated profile. A database match is not independent laboratory verification; modifications, counter-ions, and formulations can change the measured mass.
- Molecular form
- Salmon calcitonin, 32 residues
- Species
- Not established by this molecular identity audit
- Termini (N / C)
- Not specified / Prolinamide
Average reference mass
Reference policy updated: 2026-10-05
- PubChem molecular record · 2026-10-01
C-S-N-L-S-T-C-V-L-G-K-L-S-Q-E-L-H-K-L-Q-T-Y-P-R-T-N-T-G-S-G-T-P-NH2, with a Cys1–Cys7 disulfide bridge
- Molecular formula
- C145H240N44O48S2
- Average reference mass
- ≈ 3,431.9
- Receptors
- Calcitonin receptor (CTR); the same receptor family that, with RAMPs, forms amylin receptors
- Backbone
- Salmon calcitonin, 32 residues
- C-terminus
- Prolinamide
- Status
- Approved (FDA) — hypercalcaemia of malignancy; osteoporosis use has declined
- PubChem CID: 16220016
- CAS RN: 135506-95-5
- UNII: 7SFC6U2VI5
Chemistry values: curated profile, PubChem · fetched 2026-10-01.
Clinical development snapshot
ClinicalTrials.gov lists 153 registered studies with “Calcitonin” as an intervention (snapshot 2026-10-01). A registry footprint is not evidence of efficacy or approval.
| NCT | Title | Phase | Status | Updated |
|---|---|---|---|---|
| NCT07599228 | Using Virtual Reality to Teach Mindfulness to People With Migraine | Not applicable | not yet recruiting | 2026-09-30 |
| NCT07846033 | A Phase 1 Study of VK3019 in Overweight and Obese Adults Without Comorbidities | Phase 1 | recruiting | 2026-09-29 |
| NCT07699549 | Long-term Atogepant in Real-world Practice | — | completed | 2026-09-23 |
| NCT05955612 | Use of Procalcitonin, a Blood Test to Guide Antibiotic Therapy for Sepsis in Adults | Phase 3 | completed | 2026-09-22 |
| NCT07826910 | Effect of Atogepant on the Vestibulo-Ocular Reflex in Healthy Adults and Adults With Migraine | Phase 4 | not yet recruiting | 2026-09-17 |
| NCT00467506 | Phase II Two-step Radioimmunotherapy Clinical Study in Medullary Thyroid Carcinoma | Phase 2 | completed | 2026-09-14 |
Calcitonin (salmon) — reconstitution calculator
Enter how much peptide is in the vial and how much diluent (e.g. bacteriostatic water) is added. The tool returns the resulting solution concentration — and, for any amount you type, the volume it corresponds to. This is educational arithmetic, not a dosing recommendation.
Reference form: Salmon calcitonin, 32 residuesAverage reference mass: 3,431.9 Da
Enter an amount to see the volume it corresponds to.
Educational concentration mathematics only. This tool does not recommend a dose, amount, or protocol, and nothing here is medical advice. Many peptides are not authorized by Health Canada for human use — see our reconstitution and bacteriostatic-water guides for context.
Change log
Dated observations from the data pipeline (registry flags, trial footprints, identifiers) and editorial reviews of this profile.
- Trials3 registered studies added on ClinicalTrials.gov (now 153).
- IdentifiersCross-linked to PubChem CID 16220016.
- TrialsClinicalTrials.gov snapshot added: 150 registered studies, highest phase 4.
- EditorialProfile content reviewed and updated by the editorial team.
FAQ about Calcitonin (salmon)
What is Calcitonin (salmon)?+
Salmon calcitonin is a 32-amino-acid peptide (C145H242N44O48S2, ≈3,434 Da) that shares the calcitonin family's N-terminal disulfide ring and C-terminal prolinamide but differs from human calcitonin at many positions. It is the form used pharmaceutically: FDA-approved for over 30 years, commonly for hypercalcaemia of malignancy and historically for postmenopausal osteoporosis. Eel and salmon calcitonins are more potent than the human hormone in cell assays.
What Canadian product status is recorded for Calcitonin (salmon)?+
Canadian product status for Calcitonin (salmon) has not been verified in this profile. No verified record here does not mean no authorization exists. Status depends on the product, formulation and use; consult Health Canada's product records.
What is the typical length of Calcitonin (salmon)?+
Calcitonin (salmon) is commonly described as approximately 32 amino acids (Calcitonin-family hormone (fish-derived analogue)).
What is salmon calcitonin?+
A 32-residue peptide hormone with the salmon sequence, used pharmaceutically because it is more potent than human calcitonin. It lowers serum calcium by inhibiting osteoclasts.
Is salmon calcitonin approved?+
Yes — FDA-approved for over 30 years, commonly used for hypercalcaemia of malignancy and historically for postmenopausal osteoporosis.
What is the sequence of salmon calcitonin?+
CSNLSTCVLGKLSQELHKLQTYPRTNTGSGTP-NH2 with a Cys1–Cys7 disulfide bridge; formula C145H242N44O48S2, about 3,434 Da.
Why salmon rather than human calcitonin?+
Fish calcitonins are more potent than the human hormone in cell assays; eel calcitonin is more potent still, and salmon calcitonin became the standard pharmaceutical form.
How is salmon calcitonin related to cagrilintide?+
Both act on calcitonin-receptor-based signalling; cagrilintide is an amylin analogue that also activates the calcitonin receptor.
Related peptides
References & further reading
- 1.PubChem — compound summary for calcitonin (salmon) (CID 155817456)
- 2.Sortino MA et al. (1993). Comparative effects of eel calcitonin, salmon calcitonin and [Asu1,7]eel calcitonin on hypophyseal and osteoblastic function. Gynecol Endocrinol
- 3.Allison SL, Davis KW (2019). Calcitonin Stewardship Strategies. J Pharm Pract
- 4.Kuril AK et al. (2024). High-throughput method for peptide mapping and amino acid sequencing for calcitonin salmon in calcitonin salmon injection using UHPLC-HRMS. J Pharm Biomed Anal
- 5.Vondracek SF (2010). Managing osteoporosis in postmenopausal women. Am J Health Syst Pharm
- 6.Greenblatt D (2005). Treatment of postmenopausal osteoporosis. Pharmacotherapy
- 7.Drugs and Lactation Database (LactMed) — Calcitonin