Hello,
To be eligible NIPER JEE for PhD you must have completed your post graduation in Pharmacy in M.Sc/M.tech/M.Pharm/MBA(Pharm).There are various departments such as Biological Sciences, chemical Sciences, Pharmaceutical Sciences, Pharmaceutical Management.So with diploma in Pharmacy you will be ineligible.
You can have the look at the eligibility criteria for each course by clicking the link below
https://www.niperahm.ac.in/writereaddata/images/pdf/2020_Brochure_PhD-31-03-2020-2020.PDF
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