Rigel Pharmaceuticals, Inc. and Pfizer Inc. have entered into a collaborative research and license agreement for the development of inhaled products for the treatment of allergic asthma and other respiratory diseases such as chronic obstructive pulmonary disease (COPD).

The collaboration is focused on Rigel's preclinical small molecule compounds, which inhibit IgE receptor signalling in respiratory tract mast cells by blocking the signalling enzyme Syk kinase, the company announced here.

Under the terms of the agreement, Rigel will receive an upfront cash payment, as well as milestone payments and royalties on any future product sales. Pfizer will make an equity investment in Rigel and will be responsible for the worldwide development and commercialization of any resulting products. Financial terms of the agreement were not announced.

"Inhibition of Syk kinase is a novel approach to reduce the chronic inflammation in patients with allergic diseases of the respiratory tract such as allergic asthma," said Martin Mackay, senior VP, Worldwide Research & Technology for Pfizer Inc. "We believe that the combination of Rigel's novel small molecule approach and Pfizer's drug development capabilities will allow us to progress new and important treatments for respiratory diseases," he added.

Rigel has pioneered the discovery of treatments for allergic diseases by blocking Syk kinase. The Company was the first to discover and develop potent and selective Syk inhibitors and introduce these into the clinic.

The Syk kinase intrapulmonary collaboration with Pfizer does not include R112, Rigel's lead Syk kinase inhibitor that is being developed for the treatment of allergic rhinitis. Rigel recently completed a successful phase II clinical study with R112 and is proceeding with the further clinical development of R112 for allergic rhinitis. After further phase II clinical trials are completed, Pfizer will have a limited option to license R112 and Rigel's Syk inhibitors in the allergic rhinitis field under different financial and other obligations, the company informed.