After completing a Bachelor's degree (usually 4 years), a PharmD program itself takes about 4 years. Therefore, the total time commitment from an Associate's degree to a PharmD is roughly 8 years (2 years for the Associate's + 4 years for the Bachelor's + 4 years for the PharmD).
A research-focused PhD in a pharmaceutical science (e.g., pharmacology, medicinal chemistry) would also require a Bachelor's degree first. The PhD itself takes typically 4-7 years, making the total time commitment from an Associate's degree around 6-9 years (2 for Associate's + 4 for Bachelor's + 4-7 for PhD). But this isn't a PharmD.