Muscle & Performance

Abaloparatide

Abaloparatide (Tymlos) is a 34-aa PTHrP analogue with greater RG conformation selectivity than teriparatide. FDA-approved for osteoporosis. Phase III ACTIVE trial showed superior vertebral fracture reduction with lower hypercalcemia risk.

C174H268N48O53SHalf-life: ~1.7 hours subcutaneousMolar mass: 3961.50 g/mol

⚠ Research & Educational Use Only. Abaloparatide is a research chemical documented here for scientific education. All information references peer-reviewed literature and preclinical/clinical study data. Not for human consumption. Not medical advice. Consult a licensed researcher or healthcare professional before any laboratory use.

Medically reviewed by Dr. Amanda Reid, MDWritten by the KnowYourPeptide Research TeamLast updated April 2026
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Key Takeaways
  • Reduces vertebral fracture risk by 86% vs placebo (ACTIVE trial, 18 months) — superior to teriparatide in this trial (78% reduction)
  • Lower incidence of hypercalcemia vs teriparatide — important for patient tolerability and monitoring burden reduction
  • Increases lumbar spine BMD by 11% and total hip BMD by 4.1% over 18 months
  • Abaloparatide is not FDA-approved for human use. FDA-approved prescription drug (Tymlos, Radius Health/Menarini). Indicated for postmenopausal women with osteoporosis at high fracture risk.

Research At a Glance

  • Reduces vertebral fracture risk by 86% vs placebo (ACTIVE trial, 18 months) — superior to teriparatide in this trial (78% reduction)
  • Lower incidence of hypercalcemia vs teriparatide — important for patient tolerability and monitoring burden reduction
  • Increases lumbar spine BMD by 11% and total hip BMD by 4.1% over 18 months
  • RG conformation selectivity (cAMP-biased PTH1R signaling) → reduced bone resorption co-stimulation vs RG+R0 activation
Calculate Abaloparatide dose

What is Abaloparatide?

Abaloparatide (brand name: Tymlos) is a synthetic 34-amino acid peptide analogue of parathyroid hormone-related protein (PTHrP), developed by Radius Health. It received FDA approval in 2017 for the treatment of postmenopausal women with osteoporosis at high fracture risk.

Unlike teriparatide, which is a fragment of PTH, abaloparatide is derived from PTHrP — a structurally related protein that also activates the PTH1R but with different receptor conformation preferences. This difference in conformation selectivity is the mechanistic basis for abaloparatide's claimed advantages.

**PTH1R conformation selectivity:** The PTH1R exists in two conformational states: - **R0 state**: High-affinity conformation that activates both Gs (cAMP) and Gq pathways; binding is prolonged - **RG state**: G-protein-coupled state with faster dissociation kinetics

PTH preferentially binds both R0 and RG states (sustained cAMP production), while PTHrP and abaloparatide show preferential RG-state binding (shorter, more transient cAMP signaling). It is hypothesized that this RG-bias produces a more anabolic and less bone-resorptive PTH1R activation profile — potentially explaining abaloparatide's lower hypercalcemia incidence.

**ACTIVE trial results (Miller et al., JAMA 2016):** In 2,463 postmenopausal women randomized to abaloparatide 80 mcg SC, teriparatide 20 mcg SC, or placebo over 18 months: - Vertebral fracture reduction vs placebo: abaloparatide 86%, teriparatide 78% - Non-vertebral fracture reduction vs placebo: abaloparatide 43% (significant), teriparatide 28% (non-significant) - Hypercalcemia incidence: abaloparatide 3.4%, teriparatide 6.4% - Time to non-vertebral fracture reduction was faster with abaloparatide

An innovative transdermal patch formulation (ATOM trial) delivering abaloparatide through a 5-minute skin contact patch achieved similar pharmacokinetic profiles to the SC injection and is under development as a needle-free alternative.

Key Research Benefits

Documented effects observed in preclinical and clinical studies on Abaloparatide. See all Muscle & Performance peptides for comparison.

Reduces vertebral fracture risk by 86% vs placebo (ACTIVE trial, 18 months) — superior to teriparatide in this trial (78% reduction)
Lower incidence of hypercalcemia vs teriparatide — important for patient tolerability and monitoring burden reduction
Increases lumbar spine BMD by 11% and total hip BMD by 4.1% over 18 months
RG conformation selectivity (cAMP-biased PTH1R signaling) → reduced bone resorption co-stimulation vs RG+R0 activation
Approved as patch formulation (Tymlos patch, RADIUS trial) for transdermal delivery
Superior non-vertebral fracture reduction: 43% vs placebo (ACTIVE trial, significant)

Side Effects & Risks

Adverse effects reported in the research literature. All data sourced from preclinical and clinical study reports.

Hypercalcemia (less frequent than teriparatide): ~3% vs ~6% with teriparatide
Hypercalciuria
Nausea and dizziness (less than teriparatide in head-to-head data)
Injection site reactions including erythema and pain
Orthostatic hypotension after injection
Same lifetime 24-month treatment limit as teriparatide (based on preclinical rodent osteosarcoma data shared across the class)

Dosing Data from the Literature

Doses referenced below are sourced from published preclinical and clinical studies. Use the peptide dose calculator to convert these values to injection volume.

Research Dosing Protocol

Abaloparatide (Tymlos) dosing:

Approved dose: 80 mcg SC once daily Injection site: Periumbilical region of the abdomen (avoid 2-inch radius around navel) Duration: 24 months lifetime limit (same class risk as teriparatide) Post-treatment: Continue with antiresorptive therapy (bisphosphonate preferred) to maintain BMD gains

Transdermal patch (investigational): 300 mcg patch × 5 minutes daily contact — delivers ~17 mcg systemically (ATOM trial data)

Enter your vial size and target dose to get the exact injection volume.

Administration in Research Settings

Standard reconstitution and administration methodology for laboratory research use.

Inject subcutaneously in the periumbilical abdomen using the prefilled autoinjector pen. Inject immediately after removing from refrigerator. Rotate sites within the recommended area.

Explore Further

Quick Reference

Half-Life
~1.7 hours subcutaneous
Molar Mass
3961.50 g/mol
Formula
C174H268N48O53S
Legal Status
FDA-approved prescription drug (Tymlos, Radius Health/Menarini). Indicated for postmenopausal women with osteoporosis at high fracture risk.
Storage
Refrigerate at 2-8°C. Do not freeze. Use within 30 days of first use (at room temperature ≤25°C). Protect from light. Keep pen with cap on.

Research Use Only

This information is for educational research purposes only. This is not medical advice. Consult a qualified healthcare professional.