One-time zoledronate infusion after denosumab therapy may prevent bone loss for years

Administering a single infusion of zoledronate 6 months after denosumab therapy completion helps maintain the attained increases in bone mass density (BMD) for 3 years, as shown in a study. However, there is still a small number of patients who will require additional osteoporotic treatment.

The current analysis included 23 women (mean age, 65.7 years; mean body mass index [BMI], 29.3 kg/m²) who completed the 1-year follow-up observational extension of a previously reported 2-year multicentre prospective randomized clinical trial. All patients had received a mean of 4.8 denosumab injections over a mean 2.4 years prior to zoledronate (5 mg intravenously) administration.

The primary endpoint of change in lumbar spine bone mineral density (LS-BMD) at year 3 was not significant relative to year-2 values (mean, −1.2 percent; p=1.00) and to baseline values (mean, −1.75 percent; p=1.00).

While FN-BMD and C-terminal telopeptide of type 1 collagen (CTX) values remained unchanged, procollagen type 1 N -terminal propeptide (P1NP) values decreased during the third year of treatment. BMD values returned to the osteoporotic range in four patients.

No new clinical or morphometric vertebral fractures occurred, but one woman sustained a low-energy fracture of the right fifth metatarsal.

Researchers underscored a need for further investigation of determinants of responses with zoledronate, as well as the importance of the duration of denosumab treatment.