Stopping Denosumab: Whether a Bisphosphonate Bridge Is Actually Required
A single patient asking to stop a drug that's been working. The disagreement is about what happens to her bone the moment the last dose wears off, and whether skipping a bridging step is a real option or a false one.
Priscilla A., a 63-year-old woman, has been coming to the same infusion center twice a year for denosumab since her osteoporosis diagnosis five years ago, and by her own account had stopped thinking about it — until her dentist recommended an extraction and bone graft for a failing molar and mentioned, almost in passing, that she should tell her prescribing doctor before scheduling anything. That offhand comment is what brought her in today. Not a new fracture, not a bad scan: her most recent DXA shows a lumbar spine T-score that has climbed from −2.6 before treatment to −1.9 on it, which is the trajectory the drug is supposed to produce.
What she doesn't know is that denosumab cannot simply be paused. Stopping it does not leave bone turnover where treatment left it; turnover overshoots past where she started. Cummings and colleagues' pooled analysis of the FREEDOM Extension documented exactly that rebound, with multiple vertebral fractures clustering in the year after discontinuation — and, importantly for her, concentrating in patients who had already sustained a vertebral fracture before starting therapy. She has never had one. That absence does real work: it places her outside the group in which the rebound risk was most concentrated, which lowers her individual stakes without touching the pharmacology underneath them. Her timing does the opposite. Her last dose was four months ago and the next is due in two, which means the window in which turnover overshoots is not a hypothetical she can defer; it opens on a date already in the calendar. And the reason her dentist paused is a separate problem from the rebound one: osteonecrosis of the jaw risk tracks with ongoing antiresorptive exposure at the time of an invasive dental procedure, not with having ever taken the drug. So two clocks are running against each other — the one that says get the extraction done while her antiresorptive exposure is at its lowest, and the one that says do not let the next dose date pass unaddressed.
What stopping actually means for her bone
She can't simply let this dose lapse. Cummings et al.'s pooled FREEDOM Extension analysis is unambiguous: bone turnover overshoots pretreatment baseline within months of stopping, and multiple vertebral fractures cluster in the year after — this isn't a theoretical risk, it's one of the best-documented rebound effects in osteoporosis pharmacology.
The standard response is a bridging bisphosphonate given at or near the time her next dose would have been due — not instead of stopping denosumab, but timed around it so bone turnover never gets the chance to overshoot unopposed.
I'd push back gently on how alarming this needs to sound for her specifically. The rebound-fracture data is real, but it's concentrated in patients who already had a vertebral fracture before treatment — she doesn't have one, and her DXA has genuinely improved on therapy.
I'm not arguing against bridging — I agree it's appropriate — I'm arguing against framing this as an emergency for her personally when her actual risk profile is meaningfully better than the population that drove those fracture numbers.
Both of you are still answering a slightly different question than the one actually in front of us. She isn't asking whether to stop denosumab forever — she's asking how to safely get through a planned dental procedure. The oral-surgery risk this is really about is osteonecrosis of the jaw, and denosumab's ONJ risk, like bisphosphonates', is tied to ongoing antiresorptive exposure at the time of an invasive dental procedure, not to having ever taken the drug.
The actual plan is a timing question: complete the extraction while her denosumab level is at its lowest point in the cycle, use that same window to start the bridging bisphosphonate, and resume denosumab afterward if the group and she still want to continue — not "stop or don't," but sequencing three real steps in the right order.
Agreed: proceed with the dental extraction and graft during the current low-exposure window, administer the bridging zoledronic acid dose around the same time rather than waiting for the missed denosumab date to pass unaddressed, and revisit whether to resume denosumab or continue on the bisphosphonate at her next follow-up.
Not fully settled: the exact interval between the extraction and the zoledronic acid infusion — dental and endocrine input differed by a few weeks on how much healing time to allow first, and the two offices agreed to coordinate directly rather than have Priscilla relay instructions between them.