Multi-dose device for insertion into a vial and method of using the same

An multi-dose device for insertion into a vial, the device being comprised of:

• an air opening stack;
• a Luer lock port comprising a one-way valve configured such that the valve does not allow injection of air or fluid into the vial via the Luer lock port;
• and
• a double-nested needle inserter on a side of the device opposite the air opening stack and the Luer lock port,
• wherein the double-nested needle inserter is comprised of an inner needle inserter substantially surrounded by an outer needle inserter and wherein a base of the double-nested needle inserter is shaped to allow piercing a vial;
• wherein the inner needle inserter and outer needle inserter are configured to allow aspiration from a vial and simultaneously allow air to be aspirated into the vial through separate access points for each needle inserter;
• and
• wherein the air opening stack connects to one needle inserter and the Luer lock port connects to the other needle inserter.