Orexo reports on efficacy study in allergic rhinitis with OX914

Orexo has reported clinical results from an experimental phase IIa safety and efficacy study in allergic rhinitis with OX914, the first compound in its Phosphodiesterase 4 (PDE4) inhibitor program.

This program is intended to produce therapeutic molecules for the treatment of inflammatory airway diseases including rhinitis, asthma and chronic obstructive pulmonary disease ("COPD").

The trial data showed that treatment with 15 mg or 50 mg per day of OX914 did not show a statistically significant reduction in patient symptom scores after allergen provocation, compared with placebo treatment. OX914 was safe and well-tolerated and, unlike most other PDE4 inhibitors, did not show any increased evidence of nausea or vomiting compared with placebo.

While this result shows that oral treatment with OX914 is not likely to be an effective therapy in allergic rhinitis, no assessment can be made from this result in respect of its efficacy against COPD. In light of the preclinical in vivo evidence of efficacy and the molecule's strong safety and tolerability profile, Orexo will continue its ongoing discussions with several potential development partners for OX914 and the suite of back-up molecules in this series for COPD and other non-respiratory inflammatory indications.

Charlotte Edenius, Chief Scientific Officer and Head of Preclinical Research & Development commented: "Although we are disappointed that the lead molecule did not meet its primary endpoint after oral treatment in this rhinitis study, we remain confident that the PDE4 program contains very potent and targeted inhibitors of PDE4, a clinically-validated target for both COPD and asthma. We will continue with our partnering discussions for OX914 and the program for various inflammatory indications."

Trial Design

OX914 was tested in a double blind, three-way cross-over trial using an experimental model of allergic rhinitis. Over the course of three two-week periods, 36 pollen-allergic patients were treated orally with 15 mg or 50 mg of OX914 or placebo, and on days 7-13 of each treatment period, a daily allergen challenge was given in the nose. The resulting symptoms were estimated by the patient themselves using a pre-defined scale. The primary variable was the comparison of nasal symptoms, 10 minutes after allergen provocation, between 50 mg of OX914 and placebo.