Anti-CGRP monoclonal antibody therapy for migraine shows no early adverse bone effects over 6 months
Background
Migraine is a debilitating neurological disorder significantly impacting quality of life. Calcitonin gene-related peptide (CGRP) is a crucial neuropeptide involved in migraine pathophysiology, and its pathway is a target for modern preventive therapies. However, CGRP is also expressed in bone and plays a role in skeletal regulation, raising concerns about potential adverse bone effects from long-term CGRP pathway inhibition. This study addresses this gap by prospectively evaluating early bone outcomes during anti-CGRP monoclonal antibody (mAb) therapy.
Study Design
Researchers conducted a prospective, observational controlled, cohort study over 6 months. Adults with migraine initiating anti-CGRP mAb monotherapy (treated, n=27) were compared to age- and sex-matched migraine controls not receiving preventive therapy (controls, n=14). Participants underwent dual-energy X-ray absorptiometry (DXA) to assess bone mineral density (BMD) at the lumbar spine, total hip, and femoral neck, along with lumbar trabecular bone score (TBS). Serum bone turnover markers (CTX and P1NP) were also measured at baseline and 6 months. The primary endpoint was the within-treated change in BMD and TBS from baseline to month 6.
Results
At baseline, all bone parameters, including BMD, TBS, CTX, and P1NP, were within the expected age-specific ranges for both groups. After 6 months of anti-CGRP mAb exposure, all measured values remained within normal clinical ranges, indicating no clinically meaningful changes. In adjusted linear mixed-effects models, no significant group×time interactions were detected for BMD, CTX, or P1NP (all p > 0.05), suggesting no differential changes between treated and control groups for these markers. Lumbar spine TBS did show a small, statistically significant between-group difference in change over time (group×time interaction), with a greater decrease in treated patients than in controls (β = -0.052, 95% CI -0.095 to -0.008; p = 0.023).
Key Findings
- Anti-CGRP mAb therapy for migraine did not cause clinically meaningful changes in
BMD,CTX, orP1NPover 6 months. - All bone parameters remained within normal age-specific ranges after 6 months of anti-CGRP mAb exposure.
- No significant group×time interactions were found for
BMD,CTX, orP1NP(all p > 0.05). - A small, statistically significant decrease in lumbar spine
TBSwas observed in treated patients (β = -0.052, p = 0.023), but values remained normal. - Anti-CGRP treatment was clinically effective, with ≥50% and ≥75% reductions in monthly migraine days achieved by 80.8% and 42.3% of patients, respectively.
Why It Matters
Patients and clinicians can be reassured that early anti-CGRP monoclonal antibody therapy for migraine does not appear to negatively impact bone health. This finding supports the safety profile of these newer migraine preventives, alleviating a previously theoretical concern regarding CGRP's role in bone metabolism. While a small TBS decrease was noted, its clinical significance is likely minimal given values remained within normal ranges. This study suggests that bone health monitoring may not be a critical concern in the initial months of anti-CGRP mAb treatment, potentially simplifying patient management and encouraging broader adoption of these effective therapies without added bone-related precautions.
cgrp-antibody
migraine
bone-health
bone-mineral-density
monoclonal-antibody
preclinical-animal