OBJECTIVES:  To investigate whether early improvements in patient-reported outcomes (PROs) observed with certolizumab pegol (CZP) treatment were maintained over 4 years in the RAPID-PsA trial of patients with psoriatic arthritis (PsA). METHODS:  RAPID-PsA (NCT01087788) was double-blinded and placebo-controlled to Week (Wk)24, dose-blinded to Wk48 and open-label to Wk216. Patients had active PsA and had failed ≥1 DMARD. Patients originally randomized to CZP (200mg every 2 wks or 400mg every 4 wks, following 400mg loading dose at Wks 0, 2, 4) continued on assigned dose in the open-label period. PROs assessed included patient’s global assessment of arthritis pain (visual analogue scale), fatigue (numeric rating scale), HAQ-DI, SF-36 PCS, SF-36 MCS, PsAQoL, and DLQI (DLQI was assessed in the subgroup of patients with ≥3% body surface area affected by psoriasis at baseline). Data are reported for patients originally randomized to CZP at Wk0 as mean change from baseline, imputed by LOCF. RESULTS:  Of 273 patients randomized to CZP at Wk0, 248 (91%) completed Wk24 and 183 (67%) Wk216. Early improvements observed to Wk24 of CZP treatment were subsequently maintained over 4 years (to Wk216) in all PROs assessed, including patient’s global assessment of arthritis pain (Wk24: -28.5; Wk216: -32.1), fatigue (Wk24: -2.0; Wk216: -2.3), HAQ-DI (Wk24: -0.5; Wk216: -0.5), SF-36 PCS (Wk24: 8.0; Wk216: 8.8), SF-36 MCS (Wk24: 4.5; Wk216: 3.6), PsAQoL (Wk24: -3.9; Wk216: -4.5), and DLQI (Wk24: -7.6; Wk216: -7.6). Similar improvements were observed with both CZP dose regimens and in patients with and without prior anti-TNF exposure (data not shown). CONCLUSIONS:  Early improvements observed with CZP treatment to Wk24 in all PROs assessed were subsequently maintained over 4 years in patients with PsA. Similar maintained improvements were observed in both CZP dose regimens, and in patients with and without prior anti-TNF exposure.