Effect of insulin concentration on bioavailability during nasal spray administration

Area of Science:

• Pharmacology
• Endocrinology
• Drug Delivery Systems

Background:

• Type 1 diabetes requires careful insulin management.
• Exploring alternative insulin delivery methods like nasal sprays is crucial for patient convenience.
• Previous research on nasal insulin bioavailability has yielded varied results.

Purpose of the Study:

• To evaluate the bioavailability of rapid-acting insulin administered via nasal spray.
• To compare the pharmacokinetic profile of nasal insulin spray with subcutaneous insulin injection.
• To investigate the effect of insulin concentration on nasal spray bioavailability.

Main Methods:

• A study involving 6 patients with type 1 diabetes.
• Comparison of subcutaneous insulin injection with intranasal insulin spray at two concentrations (100 U/ml and 500 U/ml).
• Assay of free and total plasma insulin concentrations post-administration.

Main Results:

• Nasal insulin administration resulted in earlier peaks and faster return to basal levels compared to subcutaneous injection.
• Bioavailability of nasal spray insulin was comparable between 100 U/ml and 500 U/ml concentrations (5.14% and 4.64% respectively).
• Increased insulin concentration in the nasal spray did not significantly improve bioavailability under the tested conditions.

Conclusions:

• Nasal spray insulin offers a potentially faster absorption profile compared to subcutaneous injections.
• The bioavailability of nasal insulin spray is not dose-dependent on concentration within the tested range.
• Further research is needed to optimize nasal insulin delivery systems for improved therapeutic efficacy.