More Drugs Via the Pulmonary Route
Aside from asthma, chronic obstructive pulmonary disease, pulmonary hypertension, and cystic fibrosis, where a hospitalist could expect to use pulmonary delivered drugs, other medicines are being investigated for administration via this route. The pulmonary route may be used for tuberculosis (TB), where lower doses can be given since high doses of systemic therapy lead to significant drug toxicity.7
Inhaled vaccines are being developed, including Bacillus Calmette-Guérin (BCG) TB and respiratory syncytial virus (RSV). Parathyroid hormone for osteoporosis, human factor IX for hemophilia, and interferon α-2b for hepatitis B virus, are potential and current inhaled treatments.
New Delivery Systems: Will They Pan Out?
Knowing the lung absorbs biologic drugs with a wide range of molecular weights, solubility, and charges, is a plus for pulmonary delivery. However, pulmonary drug delivery also presents challenges. These include local toxic effects, such as cell injury, edema, and altered tissue defenses. Drug carriers, preservatives, and propellants, such as sulfites, might harm pulmonary tissue or the body.
Safety is one of the biggest concerns when companies develop new drug delivery systems. These inhaled products and methods of delivering inhaled insulin are quickly moving through clinical trials.
Only time will tell when approvals will take place, but it looks as though there will be some innovative insulin products in the near future. TH
Michele B Kaufman, PharmD, BSc, RPh, is a freelance medical writer based in New York City.
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