Background/Purpose:   The Canadian Methotrexate and Etanercept Outcome Study (CAMEO) evaluated etanercept (ETN) monotherapy vs ETN plus methotrexate (MTX) in biologic-naïve patients with rheumatoid arthritis (RA) who had an inadequate response to MTX.

Methods:   This phase 4, randomized, open-label, noninferiority study enrolled patients who had an inadequate response to MTX. All patients received ETN+MTX for 6 months; they were then randomized at month 6 to ETN monotherapy or remained on ETN+MTX for an additional 18 months. Patient-reported outcomes (PROs) were assessed at baseline and at 6, 12, 18, and 24 months and included the Short Form-36 (SF-36) Health Survey questionnaire (higher scores represent better health); Health Assessment Questionnaire Disability Index (HAQ-DI; 0=no disability to 3=severe disability), and pain based on visual analog scale (VAS; 0=no pain to 100=severe pain). The minimal clinically important difference (MCID) for the SF-36 physical and mental component scores is a change ≥2.5; for HAQ-DI is a change ≥0.22; and for the pain VAS is a change ≥10mm.

Results:   Of 258 patients enrolled, 205 were randomized at month 6 to ETN (n=98) or ETN+MTX (n=107); 53 were not randomized. These PROs through month 24 are shown (Table). As expected, on average, PROs demonstrated improvements at 6 months, when all patients had been on ETN+MTX. From month 6 (randomization) to month 24, mean improvements were maintained in both treatment arms.

Conclusion:   Clinically meaningful improvements in PROs were demonstrated from baseline to month 6.  In general, patients who discontinued MTX at month 6 and those who remained on ETN+MTX, maintained improvements to month 24.