Systems and apparatus for providing fluid communications are described. In an example, a vial access cap includes a connector having an opening for providing access to a fluid pathway； a canella extending into an interior of a vial, the canella having a fluid lumen operatively coupled to the fluid pathway and a gas lumen； and a gravity-assisted valve comprising a valve body defining an elongated valve cavity, a first port, a second port operatively coupled to the gas lumen, and a valve member movable between a sealable end of the elongated valve cavity proximal to the first port and a non-sealable end of the elongated valve cavity proximal to the second port. In other examples, a syringe including a gravity-assisted valve and a system including gravity-assisted valves are described.
