PULMONARY DRUG DELIVERY:
NEW PERSPECTIVES ON INHALERS & INHALABLES
|Next-generation of automated pulmonary
delivery testing systems
Anthony Moran, Astech Projects Ltd
Review of Product Characterization
Requirements for Aerosol Products
High Dose-Rate Aerosol Delivery of
Biologics & Macromolecules
|Efficient pulmonary delivery of biological
molecules as PROMAXX Microspheres
Dr Julia Rashba-Step, Baxter BioPharma Solutions
|Flexible, Smart & Low Cost:
The MicroDose DPI, a true platform inhaler
F. Scott Fleming
PULMONARY DRUG DELIVERY: ACHIEVEMENTS, TRENDS AND OPPORTUNITIES
When being asked what field is the most up-and-coming area in today’s applied pharmaceutical research I would point to pulmonary drug delivery. The reason is not because of the recent launch of inhaled insulin and the related press coverage, but the fact pulmonary delivery still offers many white areas on the map.
The more information is collected the more related question marks are surfacing covering the area of lung physiology and diseases, lung deposition, intelligent inhalation devices, delivery of biopharmaceuticals, absorption enhancement, controlled drug release in the lung and, last but not least, the topic of vaccination of the lung.
The fact that all areas of pharmaceutical research are very much interrelated and highly diversified, making pulmonary drug delivery a multidisciplinary effort, is more fascinating still.
The purpose of this introductory article is not to provide a deep and detailed evaluation of a particular subject in this broad field – that task is undertaken by the sponsors’ articles that follow. Rather, this piece aims to show some achievements, trends and opportunities that the lung, as a target organ for drug delivery, can offer. Most of the information that follows is based on information to be found in the recently published book, “Pulmonary drug delivery”.
What has been achieved so far? One of the pronounced achievements is probably the recent launch of the inhalable insulin product Exubera by Nektar/Pfizer. Although, the market acceptance of the product still needs to be shown, the first regulatory approval of a larger peptide has pioneered the pathway for other pulmonary applied products containing biopharmaceutical drug compounds. Since those particular drug compounds can only be administered by injection, the lung has the potential to offer an alternative, non-invasive route of administration. Still many hurdles have to be overcome and a major challenge is the low systemic bioavailability of proteins and larger peptides, such as insulin. As shown for insulin, the bioavailability is also dependent on the individual lung condition, which varies strongly between non-smokers (about 25% bioavailability of effectively inhaled dose) and smokers (about 75% bioavailability of effectively inhaled dose). Moreover, a recent study by Henry et al showed that subjects with chronic asthma absorb less insulin than healthy subjects. This means that each individual patient requires their own adjusted dosing regimen. (...)
Henrik L. Luessen, PhD Tytonis BV, Alkmaar, The Netherlands