Skip to content
Calculator
Evidence: HighPeptideFDA ApprovedPTHrP(1-34) analogFDA-approved · TymlosOsteoporosis

Abaloparatide

A synthetic version of the first 34 amino acids of PTHrP, injected daily to build bone in osteoporosis

Abaloparatide is a synthetic analog of the first 34 amino acids of parathyroid hormone-related peptide, injected once a day. Approved as Tymlos in 2017 for osteoporosis at high fracture risk, it reduced new spine fractures against placebo in the ACTIVE trial.

At a Glance Read Research →
Overview

What is it?

Parathyroid hormone and its relative, parathyroid hormone-related peptide (PTHrP), act on the same receptor, PTH1R. Teriparatide was the first drug to use a brief daily pulse there to build bone. Abaloparatide is the second: an analog of the first 34 amino acids of PTHrP, described in its phase 3 report as a selective activator of the type 1 PTH receptor.

In the ACTIVE trial, 2,463 postmenopausal women took abaloparatide, placebo or teriparatide for 18 months. Spine and non-spine fractures were less frequent on abaloparatide than on placebo, and high blood calcium was less common than on teriparatide, 3.4% against 6.4%. After two further years on alendronate, 0.9% of women who had started on abaloparatide had a new spine fracture, against 5.6% who had started on placebo.

Tymlos is approved in the US for postmenopausal women and men with osteoporosis at high fracture risk. First doses are taken sitting or lying down, as blood pressure can drop on standing; the label also warns about allergic reactions, osteosarcoma risk and high blood calcium.

Structured data

At a Glance

Every value in this table is printed from the Grey Peptides dataset, the same record the compound explorer and comparison tool read, so the three can never disagree.

ClassA synthetic analog of the first 34 amino acids of parathyroid hormone-related peptide, PTHrP(1-34), FDA-approved as Tymlos for osteoporosis at high fracture risk.
FormulaC174H300N56O49
Molecular weight3961 g/mol
Half-lifeabout 1 hour after subcutaneous injection
Label dose80 mcg (once daily, subcutaneous)
US statusFDA Approved
Evidence levelHigh
Last reviewed2026-10-02

Educational information, not medical advice. The doses on this page come from approved labels, published studies and, where no study exists, amounts reported by users. None is a recommendation for you. An unapproved compound has no established safe or effective human dose, and products sold for “research use only” are not made or tested for people. Talk to a doctor before acting on anything on this site, including before you start, stop or change any medicine or dose. Full medical disclaimer.

Interactive

Half-Life: How Much Remains

The dataset records a half-life of about 1 hour after subcutaneous injection for Abaloparatide. After each half-life, half of what was in the circulation is gone, so about 3% remains after five. Real clearance varies with the person, the dose, the route and kidney or liver function; this is arithmetic on a published figure, not a dosing tool.

Time since a single dose
ElapsedTimeRemaining
1 half-life60 min50% remaining
2 half-lives2 h25% remaining
3 half-lives3 h12.5% remaining
4 half-lives4 h6.25% remaining
5 half-lives5 h3.125% remaining
Evidence

Published Research

The studies behind abaloparatide, read from their PubMed abstracts.

Human2016

ACTIVE: abaloparatide against placebo, 2,463 women

Postmenopausal women received abaloparatide 80 µg daily, placebo or teriparatide for 18 months. Spine and non-spine fractures were less frequent than on placebo and bone density rose more (P < .001); high blood calcium occurred in 3.4% against 6.4% on teriparatide.

PMID: 27533157
Human2018

ACTIVExtend: alendronate after abaloparatide, 1,139 women

Women who finished ACTIVE took alendronate for up to 24 months. Over 43 months, 0.9% who had started on abaloparatide had a new spine fracture against 5.6% who had started on placebo, an 84% relative risk reduction.

PMID: 29800372
Human2022

ATOM: men with osteoporosis, 228 randomized

Men aged 40 to 85 took abaloparatide 80 µg or placebo daily for 12 months. Spine bone density rose 8.48% against 1.17%, total hip 2.14% against 0.01% (both p < 0.0001); injection-site reactions, dizziness and headache were among the commonest side effects.

PMID: 36190391
Human2022

ACTIVE-J: Japanese women and men, 78 weeks

Abaloparatide 80 µg daily for 78 weeks raised spine bone density 12.5% more than placebo, and total hip and femoral neck density 4.3% more each.

PMID: 35977548
Human2023

A skin patch against the injection, 511 women

Women used an experimental abaloparatide skin patch or the injection daily for 12 months. Spine bone density rose 7.14% with the patch against 10.86% with the injection, missing the trial's 2.0-point non-inferiority margin; application-site reactions affected 94.4% against 70.5%.

PMID: 37417725
Human2025

Insurance claims: abaloparatide against teriparatide

Among propensity-matched women aged 50 and over, hip fractures over 18 months occurred in 1.1% on abaloparatide against 1.4% on teriparatide (hazard ratio 0.83), and non-spine fractures in 4.4% against 5.0%. Observational, not randomized.

PMID: 39551187
Safety

Side Effects & Contraindications

Reported Side Effects

From the trials above.

● Injection-site reactions, dizziness and headache were among the most common in men (ATOM)
● High blood calcium: 3.4% against 6.4% on teriparatide (ACTIVE)
● Application-site reactions in most users of the experimental patch

Contraindications & Cautions

From the Tymlos label (DailyMed, effective August 11, 2026).

● Raised risk of osteosarcoma, including open growth plates, Paget's disease, bone metastases or past radiation to the skeleton
● Pre-existing high blood calcium or a disorder that causes it, such as primary hyperparathyroidism
● A previous severe allergic reaction to the drug
● Tested athletes — see the Sport (WADA) row below
Questions

Frequently Asked Questions

?What is abaloparatide?

A synthetic analog of the first 34 amino acids of parathyroid hormone-related peptide, injected once a day to build bone. It is sold in the US as Tymlos.

?How is it different from teriparatide?

Both give a daily pulse at the same receptor; teriparatide copies parathyroid hormone, abaloparatide PTHrP. High blood calcium was less common on abaloparatide in ACTIVE, 3.4% against 6.4%.

?What dose is used?

The labelled dose is 80 micrograms under the skin of the abdomen once a day.

?Does it prevent fractures?

In ACTIVE, spine and non-spine fractures were less frequent than on placebo over 18 months; with two years of alendronate afterwards, new spine fractures occurred in 0.9% against 5.6%.

Bibliography

References

  1. [fda] FDA. Drugs@FDA (openFDA): TYMLOS (abaloparatide) injection, NDA 208743, original approval April 28, 2017, prescription. Read October 2, 2026.
  2. [fda] FDA. Tymlos (abaloparatide) injection US prescribing information (DailyMed set 712143d9-e21e-4013-bb3b-3426a21060a8, effective August 11, 2026). Read October 2, 2026.
  3. [clinical-trial] Miller PD, et al. "Effect of Abaloparatide vs Placebo on New Vertebral Fractures in Postmenopausal Women With Osteoporosis: A Randomized Clinical Trial." JAMA, 2016;316(7):722-33. PMID: 27533157.
  4. [clinical-trial] Bone HG, et al. "ACTIVExtend: 24 Months of Alendronate After 18 Months of Abaloparatide or Placebo for Postmenopausal Osteoporosis." J Clin Endocrinol Metab, 2018;103(8):2949-2957. PMID: 29800372.
  5. [clinical-trial] Czerwinski E, et al. "The Efficacy and Safety of Abaloparatide-SC in Men With Osteoporosis: A Randomized Clinical Trial." J Bone Miner Res, 2022;37(12):2435-2442. PMID: 36190391.
  6. [clinical-trial] Matsumoto T, et al. "Abaloparatide Increases Lumbar Spine and Hip BMD in Japanese Patients With Osteoporosis: The Phase 3 ACTIVE-J Study." J Clin Endocrinol Metab, 2022;107(10):e4222-e4231. PMID: 35977548.
  7. [clinical-trial] Lewiecki EM, et al. "Efficacy and Safety of Transdermal Abaloparatide in Postmenopausal Women with Osteoporosis: A Randomized Study." J Bone Miner Res, 2023;38(10):1404-1414. PMID: 37417725.
  8. [pubmed] Tabatabai L, et al. "Comparative Effectiveness of Abaloparatide and Teriparatide in Women 50&#xa0;Years of Age and Older: Update of a Real-World Retrospective Analysis." Endocr Pract, 2025;31(2):159-168. PMID: 39551187.

Sources & Citations

Studies were read from their PubMed records; regulatory sources are listed below, read October 2, 2026.

Medical Disclaimer: This content is for educational and informational purposes only. It is not medical advice, and nothing here is an instruction to obtain or use any compound. Consult a licensed healthcare provider before making health decisions.

Last reviewed: 2026-10-02