Biologics in drug delivery

Biologics have revolutionised modern therapeutics, delivering unprecedented efficacy for previously untreatable conditions. However, their remarkable efficacy comes with significant delivery challenges stemming from their intrinsic complexity. This chapter explores how the defining characteristics of biologics, namely their molecular size, stability profile, and potential immunogenicity, directly influence delivery strategies. We examine physiological barriers these large molecules encounter, and innovative technologies developed to overcome them. From conventional parenteral approaches to emerging non-parenteral routes like oral, pulmonary, and transdermal systems, we evaluate current solutions and their limitations. As novel technologies increasingly intersect with biologics delivery, we highlight emerging opportunities to transform patient outcomes while introducing new regulatory and manufacturing considerations.