>Pharmaceutical companies typically test multiple methods of drug delivery during the development process for a new prescription drug.

No, that would be unusual.

>some drugs may be more effective when delivered intravenously (through an injection) because they can be quickly absorbed into the bloodstream and distributed to the target tissue.

Speed is rarely a concern. Exposure (duration of effect) is the common issue. Here oral delivery can have an advantage, since a pill formulation can reside in the digestive system for hours, extending the time for absorption.