I gotta agree with lord999. The PharmDs functioning as PIs are certainly the exception and not the rule. To address sdn1977 comments, I'd also agree that most PharmDs in industry are working in the Phase IV portion (ADR monitoring or helping coordinate study protocols) or are MSLs (medical science liaisons) functioning as educators of prescribers and/or drug reps about the drugs and clinical trial data. These are typically clinical or investigational pharmacists who worked in hospital pharmacies, DI centers, or academic medical centers for a couple of yrs typically w/ some publications and documented research experience and for any # of reasons decided to move on to industry. Other types of pharmacists you may see in the Phase IV arena are the PharmD/MPH (already mentioned) given their potential in epi/stats or the PharmD/PhD (PhD in pharmacoepi/outcomes) or PharmD w/ fellowship training in pharmacoepi/outcomes related work.
The people that are doing Phase I stuff are basically all kinetics people who often mastered their craft in academic medical centers >10yrs ago so they are the exceptions and probably shouldn't be used for examples for someone to try to achieve today given changes in the landscape. I only pointed some out previously as a point that yes it can be done, but yes it is also pretty rare.
From a historical perspective a good article to review would be by ACCP in 2000 "Clinical Pharmacist as the PI":
http://www.accp.com/position/pos25.pdf. But if you really want to do research (i.e. benchwork) than the PhD is the best way to go. Another template to look at would be Scott Akers, PharmD, PhD at UKY. An interesting example as he did the PharmD did residency training (2yrs) + fellowship training (2yrs) then went back to get the PhD because he felt it was necessary to complete himself as a researcher for the level of research he wants to do. Now he's on faculty at UK and only practices clinically (rounding) about one-two months/yr and functions as a mentor for the Clin PharmD/PhD program in addition to also running a cardiovawscular fellowship for those who want research training, but aren't trying to go the PhD route.
Note the research training in residency training is very minimal and at best goes no further than being able to to a good retrospective review or apply basic epi/stats to one's success in implementing a clinic and comparing it to another service.
If you want anymore than that then you either have to dedicate more free time to training yourself in the pharmacoepi/MPH arena but finding time to do so may prove difficult.
Fellowships are often for those people who find themselves somewhere in the middle. Think of it as how you would like to spend your time in a 40hr work week.
Most PharmD/PhD positions in academic are 70-80% research/ 20-30% clinical (i.e. 28-32hrs research vs 8-12hrs clinical). Most places are on the 80/20 ratio. Another point is that research may often take >40hr/wk so that may further inhibit you clinical time or you'll spend more nights in the lab completing research. Difference b/w PharmD/PhD vs PharmD/res+fellowship is that their time ratio research/clinical may be the same (i.e. 70-80% research/ 20-30% clinical) but the type of research and grants the PharmD/fellowship will be able to compete for will be on the avg. far less than the PharmD/PhD so the PharmD/PhD is simply better equipped to succeed in a basic/bench/translational research arena.
The PharmD/res+fellowship may be better equipped to succeed in the outcomes/epi arena; however, the debate would be if you don't want to do clinical practice than just go for the the PharmD/PhD pharmacoepi type degree as the PhD will help with funding and success in academia. But if you want to practice mainly and "dabble" in outcomes trials/pharmacoepi go for a residency get the clinical job in a teaching/academic medical center or clinical faculty in academia-->consider MPH?? or try to learn it on your own and try to find a mentor in your clinical practice who can assist w/ your development as a researcher and with publications and possibly some small grants along the way.
Please forgive the length on this one.