The nasal cavity is a promising site for drug delivery as it is easily accessible to patients, has a large surface area (due to the presence of microvilli), contains a thin nasal epithelium, and it can bypass first-pass metabolism. However, many conventional dosage forms (e.g. gels, solutions, suspensions) have low residence time (time at site of action) within the nasal cavity as these can be easily expelled from the application site with sneezing, as a result of mucociliary clearance, or by nasal drainage.
Mucoadhesive polymers are delivery systems developed to overcome these issues by increasing the adhesion between the polymer and the nasal mucus, inhibiting mucociliary clearance of the medication, and hence prolonging the residence time. Due to the prolonged contact between the delivery system and the application site, it is important to evaluate the toxicity potential of these polymers on the nasal mucosa.
This study was therefore designed to examine the safety and toxicological profile of MucoLox, a proprietary mucoadhesion polymer gel, using the EpiAirway tissue model (MatTek Corporation), a 3-dimensional (3D) model developed to closely resemble the structure and functionality of the human nasal mucosa.
Mucoadhesive polymers are delivery systems developed to prolong retention of medication at application sites, such as the nasal mucosa, in order to overcome the short retention time seen with many conventional dosage forms. However, the intimate contact between the mucoadhesive polymer and the nasal mucosa require these delivery systems to be non-toxic and non-irritating. This study was conducted to evaluate the safety and toxicological profile of MucoLox, a mucoadhesive polymer gel, using the EpiAirway™ tissue model, a three-dimensional (3D) model that resembles the human nasal mucosa. Results have demonstrated that MucoLox is potentially as safe as sterile water for injection since cell viability was greater than 100% for MucoLox at various concentrations. MucoLox may therefore be considered a safe mucoadhesive polymer in its ability to prolong contact between the medication and the human nasal mucosa.
Figure 1. Illustration of the EpiAirway tissue model.
Figure 2. Percent cell viability after 3 hr of exposure to MucoLox 100%, 10%, and 1%; and sterile water (negative control).
MucoLox has demonstrated to be a safe mucoadhesive polymer that can offer increased retention of medication at the site of action without toxicity concerns. Compounding pharmacists may then safely utilize this mucoadhesive polymer as a delivery system to increase the contact time between the medication and the nasal mucosa, potentially reducing the need for frequent dosing and increasing the effectiveness of each dose administration.