Real Life Proof-of-Concept Study to Assess the Effect of Methylcellulose as add-on "Seal" to the In-season Pharmacologic Rescue Treatment in Subjects With Allergic Rhinitis

Rationale. Assessment and follow up of specifically sensitized subjects with allergic rhinitis during the pollen season is traditionally based on symptom scores. Accounting for the use of rescue medication on top of symptom scores provides another dimension to the overall clinical characterization of the patients. Thus, using "combined symptom and medication scores" (CSMS) allows thorough characterization of the disease course. Guidelines recommend that CSMS are used for assessment of the effect of allergen specific immunotherapy in subjects with allergic rhinitis. Different allergic rhinitis management strategies can be evaluated and compared by means of CSMS. In the update of the ARIA guidelines of 2010, 24 recommendations have been made in relation to pharmacologic treatment. Special position paper has been devoted to severe chronic upper airway disease (SCUAD), the treatment for which has been earmarked as unmet need.

Consequently, a standardized and universally recognized rescue treatment strategy does not exist. The most common approach for handling nasal complaints in real life consists in using rescue medication for symptoms whenever they appear. This is certainly the case when symptoms appear for the first time ever, or when patients do not want to resort to allergen specific immunotherapy (ASIT) and / or regular oral antihistamine treatment for financial reasons or personal beliefs. Under these circumstances, a long list of pharmacological choices for local or systemic application is possible including antihistamines, corticosteroids, leukotriene antagonists, cromones and antimuscarinic drugs.

Formulations for local application in the nose appeal to patients with their ease of use and immediate relief. They comprise a variety of generic drugs: decongestants, antihistamines, corticosteroids and antimuscarinics. The fact that they are not ingested makes them first choice for people reluctant to take oral medications. In many cases it is possible to control the symptoms of allergic rhinitis with these formulations used per se or as adjunct rescue medication in the course of ASIT.

The question stays whether the effectiveness of nasally applied drugs can further be improved. Despite the good rationale for their mechanism of action, their efficacy is diminished by the cleaning mechanisms of the nose, rhinorrhea in particular. Slowing down of the clearance of the nasal mucosa and prolonging the contact time with the nasal mucosa would enhance their pharmaceutical effects. The investigators have demonstrated by objectively measuring nasal flow rates that "sealing" in place locally applied oxymetazoline in subjects with persistent allergic rhinitis by means of commercially available hydroxyl-propyl-methyl-cellulose (HPMC) significantly enhances the resulting decongestion and that this effect is augmented over a time span of 2 weeks without noticeable tachyphylaxis or adverse events.

The investigators set the aim to investigate whether this beneficial effect of HPMC translates into clinical benefits in a real life clinical trial for other available drug preparations for nasal delivery.