Oromucosal spray products - Viscosity impact on spray performance evaluation

In recent years, the development of oromucosal drug delivery products has garnered significant attention as an opportunity for improved drug delivery and patient acceptance. Effective oromucosal drug delivery can be achieved through the combination of formulations with spray devices to tailor the administration. According to United States and European regulatory authorities, a drug product delivered and packed in a spray device is considered a combination product. This fact compels a full characterization of both the formulation and the spray device before submission. Herein, two formulations were tested using different spray designs, and the results showed low variability in the in-use actuations between formulations. The presence of Carbopol (R) increased the viscosity and density, requiring more priming and force to actuate, especially for device A with an actuator extension. Overall, the delivered doses were uniform and met acceptance criteria. The spray pattern of formulation 1 assembled with device A was a uniform circular plume at 30 mm, with a spray angle of 25.1 degrees and a droplet size distribution (D90) between 591.3 and 650.5 mu m. This study expects to support scientists on upcoming developments of oromucosal spray products, reinforcing the importance of investigating its quality attributes and their impact on spray performance since the early stages of development.