Bone-Building Drug Shows Promise for Transplant Patients With Severe Osteoporosis

For the hundreds of thousands of people living with transplanted organs worldwide, the lifesaving surgery is only the beginning of a lifelong medical balancing act. The immune-suppressing drugs that keep the body from rejecting a new kidney, lung, or liver carry a hidden cost: they slowly drain strength from the skeleton. Now, one of the largest real-world studies of its kind suggests that a bone-building drug already proven in ordinary osteoporosis can also rebuild bone in these fragile patients, without harming the very organ that was given to save them.

The new research, conducted at Rabin Medical Center, the largest solid organ transplant center in Israel, and published in Archives of Osteoporosis, followed 39 adults who received teriparatide, a recombinant analogue of human parathyroid hormone, after kidney, lung, or liver transplantation. The investigators report that patients treated with the drug for a median of more than 22 months gained significant bone mineral density at the lumbar spine, femoral neck, and total hip, while clinicians observed acceptable metabolic safety and no episodes of graft rejection during therapy. The findings offer some of the most detailed evidence to date on anabolic osteoporosis treatment in a population that has long been underrepresented in bone research.

The scale of the skeletal problem after transplantation is difficult to overstate. In this cohort, 90 percent of patients had already suffered at least one fragility fracture before starting teriparatide, and 79 percent had multiple broken bones. The immune-suppressing glucocorticoids that nearly all transplant recipients take, at an average dose of around 7 milligrams of prednisone-equivalent per day in this study, directly impair the bone-forming cells called osteoblasts while accelerating bone resorption. Combined with pre-existing organ dysfunction, vitamin D deficiency, and the metabolic upheaval of end-stage organ disease, the result is a skeleton under relentless attack in patients who often cannot tolerate standard therapies.

Teriparatide works differently from the antiresorptive drugs, such as bisphosphonates, that are usually the first line of defense against post-transplant bone loss. Rather than slowing bone breakdown, it stimulates new bone formation by mimicking intermittent pulses of parathyroid hormone, a signal that activates osteoblasts when delivered in daily injections. This anabolic mechanism has made it a first-line option for severe glucocorticoid-induced osteoporosis in the general population. But transplant medicine has harbored a persistent worry: laboratory and clinical studies have suggested that bones in chronic kidney disease and after transplantation may become resistant to parathyroid hormone signaling, a condition linked to adynamic bone disease in which the cellular machinery for building bone falls silent. Skeptics questioned whether an anabolic drug could overcome that resistance.

The new data argue that, in many patients, it can. Among the subset of participants with paired bone density scans taken at the start and end of therapy, lumbar spine bone mineral density rose by an average of 11 percent, femoral neck density by 8 percent, and total hip density by 11 percent, gains that the authors note are comparable to responses reported in non-transplant populations and exceed what antiresorptive drugs typically achieve in transplant recipients. Statistically, the increases reached significance at all three skeletal sites. Treatment was started a median of 36 months after transplantation, once graft function and immunosuppressive regimens had often stabilized, and continued for a median of 22.3 months, a longer exposure than in most previous reports.

Fracture outcomes, though limited by small numbers, added a reassuring note. Six patients broke bones after starting teriparatide, but only two of those fractures occurred while the drug was actively being taken; the other four happened months to years after treatment had stopped. Given that nearly every participant entered the study with an already shattered fracture history, the apparent stabilization of fracture incidence during therapy is clinically meaningful, even though the retrospective design and small sample size prevented the study from formally demonstrating fracture reduction.

Safety, particularly for the transplanted organ itself, was a central question. Kidney function, measured by estimated glomerular filtration rate, declined modestly during the first six months of therapy, from an average of 73 to 64 milliliters per minute per 1.73 square meters, and then stabilized through the remainder of treatment and follow-up. Crucially, a contemporaneous matched group of transplant recipients who never took teriparatide showed a broadly similar decline over the same period, suggesting the change reflected the natural course of post-transplant kidney function rather than a drug effect. No patient progressed to end-stage kidney disease or required dialysis, and metabolic complications were rare: a single case of hypercalcemia, which resolved when the drug was stopped, and no cases of significant hypercalciuria despite most patients taking calcium and vitamin D supplements.

The study’s authors are careful to frame these results within the limits of a single-center, retrospective design. Patients were not randomly assigned; teriparatide was reserved for those with the most severe disease, often after failure of or intolerance to bisphosphonates, a selection reinforced by national reimbursement criteria in Israel. The matched control group was used only to contextualize kidney function trends, not to compare treatment effects, and causality cannot be inferred. Yet the very severity of the treated cohort strengthens the clinical signal: these were patients whose skeletons had already failed, and they still built substantial new bone. Only one randomized trial has previously tested teriparatide after transplantation, a short six-month study in kidney recipients begun during the intense immunosuppression of early recovery, which found no density gains but did prevent bone loss compared with placebo.

By including lung and liver recipients alongside kidney patients, the new study extends the evidence base to populations for which no dedicated osteoporosis treatment guidelines exist, in contrast to the organ-specific guidelines published for heart, kidney, and liver transplant care. The results align with recent observational work showing that teriparatide outperformed alendronate in renal transplant recipients and produced meaningful density gains in patients with low bone turnover, and they add histological and clinical weight to case reports of improved bone formation in heart transplant patients. Taken together, the picture emerging is that skeletal resistance to parathyroid hormone after transplantation, while a real phenomenon, is not an insurmountable barrier when therapy is timed after graft stabilization and sustained for nearly two years.

For clinicians, the message is one of selective optimism rather than blanket prescription. Teriparatide is expensive, requires daily injections, and carries a limited treatment duration, so it is unlikely to become a universal post-transplant remedy. But for the growing population of transplant survivors with severe osteoporosis, prior fractures, and few remaining options, the study suggests a viable path: an anabolic window that can rebuild what immunosuppression has torn down, administered with routine monitoring of calcium and kidney function. The authors call for prospective trials to define the optimal timing, duration, and sequencing of anabolic therapy after transplantation, questions that will only grow more urgent as transplant medicine continues to extend survival and shifts its focus toward the long-term quality of the lives it saves.

Subject of Research: Teriparatide treatment of severe osteoporosis in solid organ transplant recipients

Article Title: Teriparatide treatment of osteoporosis in solid organ transplant recipients—a single-center experience

Article References: Diker Cohen, T., Shraga-Slutzky, I., Kaminer, K., Gorshtein, A., Dotan, I., & Tsvetov, G. (2026). Teriparatide treatment of osteoporosis in solid organ transplant recipients—a single-center experience. Archives of Osteoporosis, 21(1), Article 136. https://doi.org/10.1007/s11657-026-01751-4

Image Credits: AI Generated

DOI: 10.1007/s11657-026-01751-4

Keywords: teriparatide, osteoporosis, solid organ transplantation, bone mineral density, fragility fractures, glucocorticoid-induced osteoporosis, anabolic therapy, kidney transplant, lung transplant, liver transplant, kidney function, transplant immunosuppression