By Jasmine Musakhanian
As a pharmaceutical scientist, chances are, you have already looked into a number of enabling technologies that may help improve the delivery of that difficult drug candidate. In the process, you have surely come across some options: physical modification of the drug particles; salt formation or pro-drugs; complexation with cyclodextrins; crystal modifications; solid dispersions with polymers; and lipid based systems. The last is perhaps the hardest to pin, because it includes a host of drug delivery systems ranging from simplest oily solutions to lipid bilayers, self-micro-emulsifying drug delivery systems (SMEDDS) and solid SMEDDS to the more sophisticated nano-lipid carriers and complex colloidal or solid dispersions.
How do these different approaches fare against one another for performance? An article by Marshall Crew, in the March 2014 issue of Drug Development & Delivery provides an interesting perspective on the subject, reporting that between 1970 and 2013, lipid based formulations have accounted for ~50% of new drug approvals involving solubilisation. This relative success is significant, considering the backdrop of novelty, technological limitations, and regulatory constraints surrounding lipids in the preceding decades.
Moving forward, there is a paradigm change and the field is rapidly evolving, gaining larger acceptance and interest. Noteworthy among the lipid-based drugs approved by the FDA between 2012-2013 are Absorica, an oral anti-acne (Ranbaxy); Xtandi, for metastatic prostate cancer treatment (Astellas); and Minastrin, a female hormonal regimen (Warner Chilcott).
The key to successful drug development with lipids lies in understanding their role in drug solubilisation and in absorption. With the appropriate lipid composition, a single formulation may be designed to facilitate drug solubilisation in the gut while improving drug permeation/transport across the enterocytes lining the gut; minimize first-pass elimination due to improved lymphatic uptake of lipophilic drugs; and mitigate food effects.
Which lipid systems? Where and when? How to apply them in solid dosage forms? How to design and assess lipid formulation performance?
These and other questions will be tackled by a host of experts during an upcoming AAPS Workshop, Improving Oral Bioavailability by Lipid-based Delivery in San Diego, November 1–2, 2014. Held in conjunction with the 2014 AAPS Annual Meeting and Exposition, this two-day event brings you the latest developments, guidelines, and investigational tools to predict the in vivo performance of lipid formulations.
Pharmaceutical scientists in all stages of drug development are encouraged to consider this workshop as an opportunity to expand their development toolkit which could only widen the horizon for creating new or improved medicines.