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.
Adult patients (≥ 40 years) with LBP for ≥6 months and Modic change type 1, 2, or both were included in this analysis. 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 LBP rating 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 earlier disease with non-neuropathic pain,” concluded the investigators.
Cai G, Laslett LL, Aitken D, et al. Effect of zoledronic acid and denosumab in patients with low back pain and Modic change: a proof of principle trial [published online January 3, 2018]. J Bone Miner Res. doi: 10.1002/jbmr.3376