Denosumab and zoledronic acid may be effective in relieving Modic change-related low back pain (LBP) in patients ≥40 years of age, according to study findings published in the Journal of Bone and Mineral Research.

The current study involved adult patients (≥ 40 years) with LBP for ≥6 months and Modic change type 1, 2, or both. Investigators randomly assigned patients to receive 5 mg zoledronic acid (n=35), 60 mg denosumab (n=31), or placebo (n=37).

To assess changes in LBP, investigators used the 0 to 100 Visual Analogue Scale (VAS) and the LBP 0 to 30 rating scale each month for 6 months (mean baseline VAS, 57 mm; mean baseline LBP rating scale, 18).

Study participants in the zoledronic acid group and the denosumab group had reductions in the LBPrating scale compared with those in the placebo group (-3.3; 95% CI, -5.9 to -0.7 and -3.0; 95% CI -5.7 to -0.3, respectively), but similar VAS scores (-8.2; 95% CI, -18.8 to 2.4 and -10.7; 95% CI, -21.7 to 0.2, respectively).

The size of the Modic change was not affected at 6 months by either treatment, with absolute mean differences compared with placebo of 2.8 mm2 with zoledronic acid (95% CI, -19.5 to 25.1) and -0.3 mm2 with denosumab (95% CI, -23.1 to 22.6).

Patients with type 1 Modic change treated with denosumab were the only subgroup to exhibit a significant reduction in real Modic change (-22.1 mm2; 95% CI, -41.5 to -2.7).

LBP VAS was reduced at 6 months in patients with milder disc degeneration in the zoledronic acid group, with absolute differences compared with placebo of -14.7 points (95% CI, -28.5 to -0.9) with zoledronic acid and -16.0 points (95% CI, -30.4 to -1.5) with denosumab.

Study participants reported at least 1 adverse event during the 6-month treatment (zoledronic acid, 100% of patients; denosumab, 87%; placebo, 68%). The study is limited by the small number of participants and the short follow-up period.

Overall, the pilot findings from this small trial also, “imply [that] these therapies will work better in persons with the earlier disease with non-neuropathic pain,” concluded the investigators.