Teriparatide vs abaloparatide

The two bone-building peptides — is the newer one better, or just different?

Direct head-to-head trial exists
In one paragraphBoth cut new spinal fractures by roughly 80% in their approval trials and both are daily injections for up to two years. Abaloparatide's trial included an open-label teriparatide arm: bone density at the hip rose faster on abaloparatide and high blood calcium was half as common (3.4% vs 6.4%), but the trial was not powered to compare fracture rates between the two drugs. Teriparatide has fifteen more years of use, biosimilars, and a head-to-head win over a bisphosphonate.

Side by side

A TeriparatideA Abaloparatide
LYO gradeAA
MoleculePTH(1-34), the hormone's own fragmentPTHrP(1-34) analogue, engineered for a briefer receptor signal
Approval trialFracture Prevention Trial, n=1,637, median 21 monthsACTIVE, n=2,463, 18 months (with open-label teriparatide arm)
New vertebral fractures5% vs 14% on placebo (≈65% relative reduction)0.6% vs 4.2% on placebo (≈86% relative reduction, published analysis)
Hypercalcaemia (same trial)ACTIVE, prespecified safety endpoint6.4%3.4%
Head-to-head vs another classBeat risedronate on new vertebral fractures (VERO, n=1,360)None
First approval2002 (US), 2003 (EU)2017 (US), 2022 (EU, after a 2018 refusal)
StorageRefrigeratedRoom temperature for 30 days after first use
Sport (WADA)Not prohibitedNot prohibited
Verdict

A wash on fractures, on the evidence that exists. Abaloparatide for less hypercalcaemia and no refrigeration after first use; teriparatide for the longer record, lower price and the VERO trial. Neither has anything to do with muscle.

What ACTIVE does and does not show

ACTIVE randomised 2,463 postmenopausal women to abaloparatide, placebo or open-label teriparatide for 18 months. Against placebo, abaloparatide reduced new vertebral and non-vertebral fractures. Against teriparatide, the pre-specified comparison was hypercalcaemia — 3.4% versus 6.4% — and abaloparatide won it. Bone density rose faster at the hip on abaloparatide. But the teriparatide arm was open-label and the trial was not sized to compare fracture rates between the two active drugs, so 'fewer fractures than teriparatide' is not a claim the trial supports.

What teriparatide has that abaloparatide does not

Twenty years of use, a boxed warning that was removed in 2020 after no human osteosarcoma excess appeared, biosimilars since 2017, and VERO — a double-blind head-to-head against risedronate in severe osteoporosis in which teriparatide produced fewer new vertebral fractures. Abaloparatide has no comparison against another osteoporosis drug class. Its EU approval also came the hard way: refused in 2018 over cardiovascular concerns, granted in 2022 on additional analyses.

Practical differences

Same daily injection, same two-year course, same follow-on with an antiresorptive. Abaloparatide's pen can sit at room temperature after first use; teriparatide's stays refrigerated. Abaloparatide produces less hypercalcaemia, which matters for people at risk of it. Price and availability differ by country and are outside this site's scope.

Questions people actually ask

Is abaloparatide stronger than teriparatide?
Not shown. Bone density at the hip rose faster in ACTIVE, and hypercalcaemia was lower, but fracture rates were not compared with adequate power.
Can you take either for muscle or growth?
No. Both act on bone through the parathyroid hormone receptor; neither has any anabolic-steroid or growth-hormone action, and neither is prohibited in sport for that reason.
Why was abaloparatide refused in Europe first?
The 2018 committee judged the cardiovascular safety data insufficient — palpitations and heart-rate increases were more common on the drug. It was approved in 2022 after further analysis.

References

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