- Trial Phase
- Approved
- Time to Market
- Already marketed since 2010.
- Why 4/10
- Prolia is an already-approved, marketed drug with no pending PDUFA, AdComm, or pivotal readout in the next 12 months. The defining binary (initial approval) passed in 2010. The ongoing commercial erosion from biosimilar competition is a gradual trend, not a hard binary catalyst. ImpactScore is 4 because while Prolia is a major revenue contributor, Amgen is a diversified large-cap biotech with many other growth products (Repatha, Tezspire, biosimilars, MariTide pipeline), so a single quarter's Prolia sales decline does not drive a make-or-break move for the stock.
Prolia has no upcoming regulatory catalysts; the stock-moving events are Amgen's quarterly earnings reports, where Prolia's sales trajectory and biosimilar market-share losses will be a key metric. The next quarterly report (Q4 2026 / full-year 2026) is due in early February 2027. Investors should watch whether Prolia's decline stabilizes as biosimilar competition matures, or accelerates as more biosimilars enter.
Price Chart
Executive Summary
Prolia (denosumab) is Amgen's blockbuster twice-yearly injectable for osteoporosis, first approved by the FDA in 2010. Its primary US patent expired in February 2025, unleashing a wave of biosimilar competition. In Q3 2026, Prolia sales fell 45% year-over-year to $632 million as at least nine biosimilar pairs have been approved and six-plus have launched. Amgen's diversified portfolio (total Q3 2026 revenue up 8% to $10.37B) partially offsets the erosion, but the denosumab franchise faces sustained pricing and volume pressure with no catalyst to reverse the trend.
How It Works
Prolia is a monoclonal antibody that blocks a protein called RANKL, which acts like a switch that turns on bone-destroying cells (osteoclasts). By blocking that switch, Prolia slows bone breakdown, increases bone density, and reduces fracture risk. It is given as a shot under the skin every six months.
Trial Status
Prolia was first FDA-approved in June 2010 for postmenopausal osteoporosis and has since been approved for men with osteoporosis, glucocorticoid-induced osteoporosis, and bone loss in patients receiving certain cancer treatments. It is a mature, marketed product with over 16 years of real-world use. No new pivotal trials are ongoing for Prolia itself.
The Two-Sided Case
Upcoming Catalysts
- No upcoming PDUFA dates or pivotal readouts for Prolia; the drug is already approved and faces no pending regulatory decisions. The key ongoing dynamic is biosimilar market-share erosion.
Source Filing
The SecBot filing or press-release report that triggered this drug report:
Amgen PRESS-RELEASE AMGN ·Originating report