This multicenter , adaptive , double-blind , parallel-arm study randomized patients ( N = @,@ ; mean baseline age @ years ; HbA@c @ % -LSB- @ mmol/mol -RSB- ; weight @ kg ; diabetes duration @ years ) to dulaglutide @ mg , dulaglutide @ mg , sitagliptin @ mg , or placebo ( placebo-controlled period up to @ weeks ) .