Bacteriophages as nanocarriers for targeted drug delivery and enhanced therapeutic effects

The effective delivery of therapeutic agents is as important as the active therapeutic agent because it may make or mar the outcome. Traditional/conventional drug delivery systems (DDSs) face many limitations, including poor bioavailability, poor specificity and targeting, inconsistent drug adsorption, short half-life, rapid drug clearance, instability, varying and suboptimal drug effects, uncomfortable administration, limited drug loading into delivery vehicles, and poor treatment adherence and compliance, opening the way for innovations, including optimising the use of nanocarriers. Nanocarriers encapsulate and deliver drug agents using nanosized vehicles to enhance drug effectiveness, bioavailability as well as specific, targeted, and controlled drug release. Examples of such nanocarriers include micelles, microemulsions, nanoemulsions, lipid nanoparticles, liposomes, niosomes, dendrimers, and exosomes, which are formulated using different vehicles. Virus-like nanoparticles are emerging, with most involving bacteriophages-the environmentally ubiquitous, abundant, and diverse group of nanosized structurally simple viral particles with the intrinsic and inherent ability to invade bacteria. Studies involving different bacteriophages, their nano drug formulation, and their application against some diseases exist; however, no current review aggregates the advances made so far, which could be attributed to the recency of the research areas. Such a review is vital because it highlights and precipitates milestones and can provide necessary basis for further advancements. Thus, this study aims to evaluate the advancing potential use of bacteriophages as nanocarriers for targeted drug delivery and their potential for enhanced therapeutic effects. The bioengineering of phages to display ligands leads to specific targeting, reduced toxicity, enhanced cellular uptake of an incorporated drug/gene and, ultimately, increased therapeutic efficacy.