A vial access device (200) comprising: an outer shell (216) defining an annular space and an interior space (228)； an inner casing (218) having a body (230) defining a central opening (234), at least a portion of the inner casing (218) located within the inner space (228) of the outer casing (216)； a connector (220) configured to mate with a mating connector, the connector (220) having a body (244) defining a central passageway (246) and a flange (248) extending radially out of the body (244) ； a pressure compensation system (224) placed within the space of the outer casing (216), the pressure compensation system configured to change a volume of space defined by the first space and the pressure compensation system (224)； a vial connection element (252) configured to be attached to a vial (80), the vial connection element (252) having a body (260) and a tip element (266) extending from the body (260 ), with the tip member (266) defining a fluid passageway (268) and a ventilation passageway (270), the fluid passageway (268) in fluid communication with the central passageway (246) of the connector (220), the ventilation passage in fluid communication with the first space； and a filter (258), characterized in that the first space is an annular space (226) in that the flange (248) and the outer casing (216) define a filter space (256), the filter space (256) in fluid communication with the annular space (226) and the ventilation passageway (270) in fluid communication with the filter space (256), and because the filter is placed in the filter space.Un dispositivo de acceso a vial (200) que comprende: una carcasa exterior (216) que define un espacio anular y un espacio interior (228)； una carcasa interior (218) que tiene un cuerpo (230) que define una abertura central (234), al menos una parte de la carcasa interior (218) situada dentro del espacio interior (228) de la carcasa exterior (216)； un conector (220) configurado para acoplarse a un conector de acoplamiento, teni
