Theoretical Formulation Strategies towards Neutralizing Inter-individual Variability Associated with Tacrolimus Immunosuppressant Therapy: A Case Study on Nextgeneration Personalized Medicine.

Individualizing drug therapy and attaining maximum benefits of a drug devoid of adverse reactions is the benefit of personalized medicine. One of the important factors contributing to inter-individual variability is genetic polymorphism. As of now, dose titration is the only followed golden standard for implementing personalized medicine. Converting the genotypic data into an optimized dose has become easier now due to technology development. However, for many drugs, finding an individualized dose may not be successful, which further leads to a trial and error approach. These dose titration strategies are generally followed at the clinical level, and so industrial involvement and further standardizations are not feasible. On the other side, technologically driven pharmaceutical industries have multiple smart drug delivery systems which are underutilized towards personalized medicine. Transdisciplinary research with drug delivery science can additionally support the personalization by converting the traditional concept of "dose titration towards personalization" with novel "dose-cum-dosage form modification towards next-generation personalized medicine"; the latter approach is useful to overcome gene-based inter-individual variability by either blocking, to downregulate, or bypassing the biological protein generated by the polymorphic gene. This article elaborates an advanced approach to implementing personalized medicine with the support of novel drug delivery systems. As a case study, we further reviewed the genetic polymorphisms associated with tacrolimus and customized novel drug delivery systems to overcome these challenges factored towards personalized medicine for better clinical outcomes, thereby paving a new strategy for implementing personalized medicine for all other drug candidates.