rac ran ial ▁ble eding . ▁Ble ed ings ▁were ▁particularly ▁increased ▁in ▁elder ly ▁patients ▁and ▁those ▁with ▁ren al ▁imp air ment . ▁ ▁San of i ▁dis cont in ued ▁the ▁development ▁of ▁id ra par in ux ▁sod ium ▁in ▁favour ▁of ▁a ▁bi ot in yl ated ▁form ulation ▁of ▁the ▁drug ▁called ▁id rab iot ap arin ux ▁sod ium . ▁ ▁Method ▁of ▁action ▁Id ra par in ux ▁select ively ▁blocks ▁co ag ulation ▁factor ▁X a . ▁ ▁See ▁He par in : ▁Mechan ism ▁of ▁ant ico ag ul ant ▁action ▁for ▁a ▁comparison ▁of ▁the ▁mechanism ▁of ▁he par in , ▁low - m ole cular - weight ▁he par ins , ▁fond ap arin ux ▁and ▁id ra par in ux . ▁ ▁Id rab iot ap arin ux ▁ ▁Id rab iot ap arin ux ▁sod ium ▁is ▁also ▁admin ister ed ▁once - week ly . ▁It ▁has ▁the ▁same ▁pent as ac char id ic ▁structure ▁as ▁id ra par in ux ▁sod ium , ▁but ▁with ▁bi ot in ▁attached , ▁which ▁allows ▁its ▁neutral isation ▁with ▁av id in , ▁an ▁egg - der ived ▁protein ▁with ▁low ▁ant igen icity . ▁San of i ▁conducted ▁three ▁phase ▁III ▁tri als ▁of ▁id rab iot ap arin ux ▁sod ium ▁between ▁ 2 0 0 6 ▁and ▁ 2 0 0 8 ▁in ▁approximately ▁ 1 3 , 5 5 0 ▁patients . ▁In ▁one ▁phase