Phase 1b randomized, double-blind study of namilumab, an anti-granulocyte macrophage colony-stimulating factor monoclonal antibody, in mild-to-moderate rheumatoid arthritis

• DOI: 10.1186/s13075-017-1267-3
• Publication Date: 2017-03-09T02:09:09Z
• Authors: T. W. J. Huizinga; A. Batalov; R. Stoilov; E. Lloyd; T. Wagner; D. Saurigny; B. Souberbielle; E. Esfandiari
• Keywords: Tolerability; Erythrocyte sedimentation rate

Namilumab (AMG203) is an immunoglobulin G1 monoclonal antibody that binds with high affinity to the GM-CSF ligand. This was a phase 1b, randomized, double-blind study (PRIORA) assess namilumab in active, mild-to-moderate rheumatoid arthritis (RA). The primary outcome safety and tolerability of repeated subcutaneous injections patients RA. Adults RA on stable methotrexate doses for ≥12 weeks were eligible. Patients received three 150 or 300 mg, placebo days 1, 15, 29, 12 weeks' follow-up. Primary objective safety/tolerability. cohort 1 randomized mg (n = 8) 5). In 2, 7) 4). Incidence treatment-emergent adverse events (TEAEs) similar across groups (namilumab mg: 63%; 57%; placebo: 56%). TEAEs ≥10% nasopharyngitis (17%) exacerbation/worsening (13%). No anti-namilumab antibodies detected. pharmacokinetics linear typical administration. post hoc efficacy, per protocol analysis 21), showed greater improvement Disease Activity Score 28 (erythrocyte sedimentation rate C-reactive protein [CRP]), swelling joint counts tender compared placebo. Difference mean DAS28-CRP changes from baseline between favored at both all time points. addition area under curve analyzed as time-adjusted change baseline. A significant shown (150 combined) day 43 (p 0.0117) also 8 after last dosing 99 0.0154). Subcutaneous generally well tolerated. Although demonstrated preliminary evidence patient numbers small; 2 studies are ongoing. ClinicalTrials.gov, NCT01317797 . Registered 18 February 2011.