BackgroundGuselkumab (GUS) is a human monoclonal antibody targeting the interleukin-23p19-subunit. It has demonstrated efficacy at Week 24 in the Phase IIIb COSMOS clinical trial of patients with active psoriatic arthritis (PsA) and inadequate response or intolerance to one or two tumour necrosis factor inhibitors (TNFis).1ObjectivesThe aim of this post hoc analysis was to identify predictors of minimal disease activity (MDA) with GUS at Week 24 in patients with active PsA and inadequate response or intolerance to one or two TNFis.MethodsA multiple logistic regression analysis was performed to identify potential predictors of MDA with GUS at Week 24 in TNFi-refractory patients with PsA. Odds ratios, 95% confidence intervals and p-values were calculated. Baseline characteristics assessed as predictors included age, sex, body mass index (BMI), C-reactive protein (CRP), other medication use and disease duration. Clinical features included tender and swollen joint counts (TJC/SJC), affected joint location, dactylitis, enthesitis, spondylitis, Psoriasis Area and Severity Index (PASI) score and psoriasis (PsO) localisation (Figure 1). Missing data for MDA at Week 24 were imputed as non-response; missing baseline values were imputed for two patients.Figure 1.Odds ratios and 95% CIs for potential predictors of minimal disease activity response to guselkumab 100 mg every 8 weeks at Week 24 in patients with PsA and an inadequate response or intolerance to one or two prior TNF inhibitors.BMI, body mass index; CI, confidence interval; CRP, C-reactive protein; csDMARD, conventional systemic disease-modifying anti-rheumatic drug; HAQ-DI, Health Assessment Questionnaire - Disability Index; MDA, minimal disease activity; PASI, Psoriasis Area and Severity Index; PsA, psoriatic arthritis; PsO, psoriasis; TNF, tumour necrosis factor.N=187 for all clinical features and baseline characteristics. Negative predictors are indicated by bold text and positive predictors by italicisation (p<0.05).ResultsOf the 187 patients in this study, 54.6% were women and the mean disease duration was 8.3 years. The patients had a mean TJC 0–68 of 21.0, a mean SJC 0–66 of 10.3, a mean PASI score of 11.6 and a mean BMI of 28.9. Furthermore, 67.9% had enthesitis and 35.8% had dactylitis at baseline. One prior TNFi had been received by 88.2% of patients, and two received by 11.8%. At Week 24, 17.1% of patients (32/187) achieved MDA. Wrist involvement (p=0.031) and scalp PsO (p=0.049) were positive predictors of MDA. Women were significantly less likely to achieve MDA (p=0.036) than men; other negative predictors included involvement of shoulder or small joints of the hand, and hand/foot PsO (all p<0.05). Age, BMI, CRP, TJC/SJC, HAQ-DI, PASI, spondylitis, enthesitis, dactylitis, other medication use and number of prior TNFis were not predictive of MDA (Figure 1).ConclusionBaseline characteristics and clinical features may be positively (wrist involvement, scalp PsO) or negatively (female sex, involvement of shoulder or small joints of the hand, hand/foot PsO) associated with achieving MDA with GUS at Week 24 in a TNFi-refractory population. Though the low patient number limits the generalisability of this analysis, assessment of Week 48 data may further elucidate potential predictors of MDA after longer-term treatment.References[1]Coates C et al. Ann Rheum Dis 2021; 0: 1–11.Disclosure of InterestsWilliam Tillett Speakers bureau:, Consultant of:, Grant/research support from: William Tillett has received research grants and consulting or speaker fees from AbbVie, Amgen, Celgene, Eli Lilly, Janssen, MSD, Novartis, Pfizer and UCB., Sarah Ohrndorf Speakers bureau: Sarah Ohrndorf has received speaker fees or travel expense reimbursements from AbbVie, BMS, Janssen, Novartis and Pfizer., Julio Ramírez Speakers bureau:, Consultant of: Julio Ramírez has received consulting or speaker fees from AbbVie, Amgen, Eli Lilly, Janssen, Novartis and UCB., Marlies Neuhold Shareholder of: Johnson & Johnson., Employee of: Janssen, Robert Wapenaar Shareholder of: Johnson & Johnson., Employee of: Janssen, Elke Theander Shareholder of: Johnson & Johnson., Employee of: Janssen, Christine CONTRE Shareholder of: Johnson & Johnson., Employee of: Janssen, Mohamed Sharaf Shareholder of: Johnson & Johnson., Employee of: Janssen, May Shawi Shareholder of: Johnson & Johnson., Employee of: Janssen, Marijn Vis Speakers bureau:, Consultant of:, Grant/research support from: Marijn Vis has received research grants and consulting or speaker fees from AbbVie, Amgen, Eli Lilly, Janssen, Novartis, Pfizer, UCB and the Dutch Arthritis Foundation.