Peptides
Calcitonin
A bone-resorption hormone medicine whose older fracture trial needs to be read alongside current regulatory limitations.
Older randomized fracture study with attrition and inconsistent exposure response; current label limits; checked 2026-10-01
Also known as: Salmon calcitonin · Miacalcin
Practical use
Clinical purpose, evidence and review questions
- Bring the treatment history
- List prior osteoporosis medicines, why alternatives were unsuitable and previous fractures.
- Read the whole result
- Keep completion rates and all active study groups alongside the headline.
- Review continuing need
- Ask how benefits, nasal symptoms, calcium status and the label’s safety concerns are being reassessed.
Overview
Calcitonin inhibits osteoclast activity. This guide focuses on salmon-calcitonin nasal spray. Current US labeling reserves it for selected women more than five years past menopause when alternative osteoporosis treatments are unsuitable, and states that fracture-reduction efficacy has not been demonstrated.
Risks and limitations
Risks include serious allergy, low calcium and nasal irritation or ulceration. Labeling also highlights a possible malignancy association from pooled trials, requiring periodic reassessment of need. Breathing difficulty or facial swelling needs emergency care; persistent nasal bleeding or sores need review.
How to read this
A positive older study and a restrictive current label can coexist. An honest guide shows both, rather than promoting the trial headline as an unrestricted present-day benefit claim.
Research explained
PROOF: five-year osteoporosis study
Who was studied
1,255 postmenopausal women with established osteoporosis randomized to three nasal calcitonin groups or placebo. Only 511 completed five years; 1,108 had at least one follow-up spinal radiograph.
What was found
The prespecified middle-exposure group had 51/287 new vertebral fractures versus 70/270 with placebo: reported relative risk 0.67 (95% CI 0.47–0.97). The other two active groups did not significantly differ from placebo.
What it cannot establish
Substantial attrition and lack of a consistent pattern across exposures limit interpretation. These data do not justify claiming established fracture prevention under today’s US nasal-spray label.
Read the original studyPreserve the unfavorable findings
The nonsignificant groups and high dropout rate are part of the result, not footnotes to be omitted.
Supporting sourceA safety signal is not a proven individual cause
The label’s pooled malignancy concern supports continued benefit–risk review. It does not prove that a particular patient’s cancer was caused by calcitonin.
Supporting sourceClaims versus findings
Not supported
PROOF establishes calcitonin as a general first-choice fracture-prevention medicine.
The current label restricts use when alternatives are unsuitable and explicitly limits the fracture-efficacy claim.
Check the evidenceCommon questions
Was the reported 33% a drop of 33 percentage points?
No. It was a relative-risk reduction; the observed proportions were about 18% versus 26% in that comparison.
SourceSources
PROOF: five-year osteoporosis study
US prescribing information; checked October 1, 2026
Sources checked 2026-10-01.
General education; not a personal treatment plan.