It is a good option to go for MPH after you get a BPharma degree specially if you want to go into RnD. It depends on what you want to end up doing.
The most taken route (which pays good) is M.PHARMA then PhD. After this you can go in Teaching or research or even in hospital pharmacy etc. You can also go for a MBA degree after BPharma or even open up your own pharmacy. For more details you can click on https://www.careers360.com/courses/mph-master-of-public-health