A method of preparing a drug product, comprising: introducing a volume of a formulated drug substance into a primary packaging component using an automatic filling machine or a semi-automatic filling machine, wherein the primary packaging component is a prefillable syringe, the prefillable syringe having a body and a flange surrounding an opening at a proximal end of the syringe and a passage leading to a needle at a distal end of the syringe, and the volume of the formulated drug substance is greater than a nominal volume of the primary packaging component, namely between 110% and 140% of the nominal volume of the primary packaging component; positioning a stopper within the primary packaging component, wherein a top of the stopper is inserted past a distal side of the flange by a distance A, wherein positioning the stopper comprises applying a vacuum to the stopper, wherein the vacuum is applied to the stopper during a vacuum stoppering process or a vacuum-assisted stoppering process in order to draw the stopper into the prefillable syringe; and connecting a plunger rod to the stopper via a connector; wherein the stopper is inserted into an interior of the body before the plunger rod is connected to the inserted stopper by the connector, wherein distance A is large enough such that any tilting of the plunger rod, once connected to the stopper, is limited by contact with a wall of the body to less than a given angle relative to a longitudinal axis of the body and is not sufficient to allow stopper to pull away from the wall of the body and become dislodged or otherwise compromised, wherein the given angle is 20°. introducing a volume of a formulated drug substance into a primary packaging component using an automatic filling machine or a semi-automatic filling machine, wherein the primary packaging component is a prefillable syringe, the prefillable syringe having a body and a flange surrounding an opening at a proximal end of the syringe and a passage leading to a needle at a distal end of the syringe, and the volume of the formulated drug substance is greater than a nominal volume of the primary packaging component, namely between 110% and 140% of the nominal volume of the primary packaging component; positioning a stopper within the primary packaging component, wherein a top of the stopper is inserted past a distal side of the flange by a distance A, wherein positioning the stopper comprises applying a vacuum to the stopper, wherein the vacuum is applied to the stopper during a vacuum stoppering process or a vacuum-assisted stoppering process in order to draw the stopper into the prefillable syringe; and connecting a plunger rod to the stopper via a connector; wherein the stopper is inserted into an interior of the body before the plunger rod is connected to the inserted stopper by the connector, wherein distance A is large enough such that any tilting of the plunger rod, once connected to the stopper, is limited by contact with a wall of the body to less than a given angle relative to a longitudinal axis of the body and is not sufficient to allow stopper to pull away from the wall of the body and become dislodged or otherwise compromised, wherein the given angle is 20°.