ORx Science & Technology

 

Drug Delivery Challenges

The therapeutic effect and clinical benefits of drugs are largely dependent on their bioavailability in the body. Although oral route of drug administration is the most convenient and preferred route of drug ingestion, poor oral bioavailability often dictate alternative and more inconvenient choices such as sterile injections.

 

In addition poor bioavailability may lead to more frequent and/ or larger doses. The lack of dose efficiency invariably induces significant adverse effects compounded by the less patient-friendly dosing regimen.

Bio-absorption of a drug is determined by its intrinsic physicochemical properties which must render it soluble in the gastro-intestinal fluid as well as permit adequate permeability in the gastrointestinal membrane in order to reach the blood circulation.

 

A particular challenge in drug delivery is the problems encountered with class III drugs that are soluble yet poorly permeable in the gastrointestinal walls. These class of drug compounds are often prescribed in large multiple doses over the course of the day. Approximately forty-five percent of newly discovered drugs (new chemical entities) and almost thirty percent of existing therapeutic compounds are class III drugs. Due to their inherent properties and current technological challenge, these drugs are currently administered as multiple daily oral doses and injections. The combination of the large pill burden and side effects associated with the large daily doses increase patient non-compliance and ultimately diminished efficacy in the patient population.