Janssen continues to strengthen the case that its interleukin-23 inhibitor TREMFYA (guselkumab) offers promise to many patients with psoriatic arthritis (PsA). The company’s phase 3b COSMOS clinical trial involving 189 patients with active PsA and an inadequate response to one to two previous tumor necrosis factor (TNF) inhibitors, guselkumab showed sustained improvements in measures of…