Improved in vitro-in vivo correlation (IVIVC) in freeze-dried particle deposition patterns of antigen-containing liposomes
Matteo Aroffu1,2, Fátima García-Villén2, Maria Letizia Manca1, Maria Manconi1 & José Luis Pedraz2
1 Department of Scienze della Vita e dell’Ambiente, University of Cagliari, via Ospedale 72, 09124, Cagliari, Italy
2 Laboratory of Pharmaceutics, School of Pharmacy, University of the Basque Country (UPV/EHU), paseo de la Universidad 7, 01006, Vitoria-Gasteiz, Spain
Summary
Several infective diseases develop due to air-borne pathogens. Therefore, being able to counteract them already at the entry site may make it possible to avoid their spread. Lung vaccination offers the possibility to reach local immunisation along with systemic immunisation. Moreover, it allows to meet patients’ needs for a painless, self-administration.
Consequently, freeze-dried liposomal nanovaccines carrying ovalbumin as antigen model have been specifically designed to be administered by the lungs. A commercial device characterized by low resistance, the Aerolizer®, was chosen as dry powder inhaler (DPI). However, when it comes from inhalant dry powders, the choice of the device is not the only relevant element in terms of lung delivery. Patient’s state of health must be considered too. Therefore, we assessed powders’ behaviour simulating healthy, asthmatic and COPD patients’ inhalation profiles by means of a breathing simulator coupled to the next generation impactor (NGI). Moreover, in order to get a better in vitro-in vivo correlation (IVIVC), we combined them with the adult Alberta idealised throat (AIT).
Finally, considering that the mucus lining the respiratory mucosa is the main obstacle in antigen transport, we analysed the penetration of vesicular nanovaccines through an artificial mucus model either in presence of the patented mucolytic BromAc® or not.
Key Message
This study evaluates the inhalation performances of a pulmonary vaccine designed as a dry powder in healthy, asthmatic and COPD profiles, highlighting how specific diseases can influence lungs deposition parameters, especially in terms of fine particle dose (FPD) thus affecting therapeutic outcome.