RANCHO CUCAMONGA, Calif. — December 15, 2025 — Amphastar Pharmaceuticals, Inc. announced that the U.S. Food and Drug Administration (FDA) has approved its Abbreviated New Drug Application (ANDA) for teriparatide injection, USP, delivered via a single-patient-use prefilled pen. The FDA determined Amphastar’s product to be bioequivalent and therapeutically equivalent to FORTEO®, marking a major regulatory milestone for the company and introducing Amphastar’s first pen-device combination drug product to the U.S. market.
Science Significance
From a scientific standpoint, teriparatide is a recombinant parathyroid hormone (PTH 1-34) that stimulates new bone formation, distinguishing it from antiresorptive osteoporosis therapies. Amphastar’s approval confirms that its formulation and delivery system achieve equivalent pharmacokinetics, efficacy, and safety to the reference listed drug. The integration of teriparatide into a prefilled pen device represents an important advancement in drug–device combination science, ensuring accurate dosing, stability, and patient usability for daily administration. Manufactured entirely in-house, the product reflects robust formulation science, device engineering, and injectable drug development expertise.
Regulatory Significance
Regulatorily, FDA approval of Amphastar’s teriparatide injection validates compliance with cGMP requirements, device quality standards, and bioequivalence criteria under the ANDA pathway. The approval of a combination product highlights Amphastar’s ability to meet both drug and device regulatory expectations, including chemistry, manufacturing, and controls (CMC), human factors considerations, and product performance requirements. This milestone reinforces the FDA’s confidence in Amphastar’s U.S.-based manufacturing infrastructure, inspection readiness, and quality systems, all of which are critical to sustaining long-term regulatory compliance.
Business Significance
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Commercially, the approval positions Amphastar to enter a U.S. teriparatide market valued at approximately $585 million in annual sales. By offering a domestically manufactured, in-house developed product, Amphastar differentiates itself in a competitive generic landscape where many suppliers rely on overseas production. The company plans to launch the product by year-end 2025, supporting near-term revenue growth while expanding its injectable and combination-product portfolio. The approval also demonstrates Amphastar’s operational agility and strengthens its broader pipeline strategy, which includes multiple ANDAs, biosimilar insulin, and proprietary injectable and intranasal therapies.
Patients’ Significance
For patients, the newly approved teriparatide injection provides an effective, FDA-approved alternative for managing osteoporosis at high risk of fracture, including postmenopausal women, men with primary or hypogonadal osteoporosis, and patients with glucocorticoid-induced osteoporosis. The easy-to-use prefilled pen supports adherence to daily therapy, while therapeutic equivalence offers confidence in clinical effectiveness and safety. Increased competition in this therapeutic category may also contribute to improved access and affordability, which is especially important for patients requiring long-term osteoporosis treatment.
Policy Significance
At the policy level, the approval underscores the importance of domestic pharmaceutical manufacturing in strengthening U.S. drug supply chain resilience. Amphastar’s fully in-house production model aligns with broader regulatory and governmental priorities focused on reducing dependence on foreign manufacturing for essential medicines. The approval of a generic combination product also reflects ongoing policy efforts to encourage high-quality competition, expand patient access, and maintain rigorous standards for safety, efficacy, and quality within the generic drug approval framework.
The FDA approval of Amphastar’s teriparatide injection pen represents a convergence of scientific rigor, regulatory compliance, and strategic manufacturing execution. As the company’s first approved pen-device combination product, the milestone highlights Amphastar’s growing capabilities in complex drug delivery systems and reinforces its commitment to U.S.-based innovation and quality-driven production. For the cGxP.wire audience, the announcement exemplifies how robust quality systems, regulatory discipline, and patient-focused design translate into meaningful advances in regulated pharmaceutical development.
Source: Amphastar Pharmaceuticals, Inc. press release
