A placebo-controlled, randomized, double-blinded study evaluating the safety of etanercept in patients with rheumatoid arthritis and concomitant comorbid diseases. - Weisman MH; Paulus HE; Burch FX; Kivitz AJ; Fierer J; Dunn M; Kerr DR; Tsuji W; Baumgartner SW (Rheumatology (Oxford, England), 2007)