Merck & Co is planning to take its house dust mite allergy immunotherapy tablet (HDM AIT) into Phase III clinical trials in North America next year.   

The pill - for which Merck gained US/Canadian rights through its merger with Schering-Plough in 2009, which itself licensed rights from Dutch allergy group ALK - is designed to protect against HDM-induced hay fever and asthma.

HDM allergy is the most common allergy in the world, affecting around 90 million people in Europe, North America and Japan, and is a major cause of allergic asthma.

Symptoms of HDM can limit daily activities, impair lung function, and lead to "significant use of symptomatic medication", according to ALK, which is overseeing the drug's development in Europe, where it is known as Mitizax.

Merck's North American Phase III trial should include around 1,500 patients, and will look into the safety and efficacy of the drug in the treatment of HDM-induced allergic rhinitis/rhinoconjunctivitis in children and adults. 

Milestone to ALK

Patient recruitment is expected to start in 2013 and complete in 2015, the firm said, and initiation of patient dosing will trigger an undisclosed milestone payment to ALK.

In Europe, a Phase III clinical programme conducted by ALK is showing promising results, the Dutch group said, noting that a recent clinical Phase II/III study met its primary endpoint and showed a significant cut in the need for asthma medication.