Regeneron's would-be blockbuster completes the allergic circle with Phase II success

Regeneron Vice President of Program Direction Neil Graham

Regeneron ($REGN) and partner Sanofi ($SNY) have notched another midstage milestone with their in-development allergy drug, a victory that affirms the hypothesis behind a treatment the companies believe could bring in billions.

The drug, dupilumab, works by blocking interleukin-4 and interleukin-13, proteins tied to inflammation. In a Phase IIa proof-of-concept study, the injected treatment met its primary endpoint of reducing the size of nasal polyps and hit its secondary goals of improving sinusitis, nasal air flow and patient-reported symptoms, Regeneron said, also tamping down asthma in patients with that comorbidity.

Those results build on a previous Phase IIb in which dupilumab significantly cleared the skin of patients with severe eczema (atopic dermatitis) and another midstage trial in which the drug substantially relieved asthma symptoms. The string of success supports Regeneron's unified theory of dupilumab: that each of the three diseases carries an underlying inflammatory link, and that blocking IL-4 and IL-13 can treat them all at once, Vice President Neil Graham said.

"There is growing recognition that patients suffering from one type of allergic disease often have additional allergic conditions" Graham said in a statement. "For example, many patients with chronic sinusitis with nasal polyps also have asthma or atopic dermatitis and vice versa. The new data reported today, together with prior Phase II data with dupilumab in asthma and atopic dermatitis, support the growing body of scientific evidence that these conditions may result from a core allergic inflammatory process driven by the IL-4/IL-13 pathway."

Now Regeneron and Sanofi are mounting an ambitious Phase III effort, starting with eczema before moving on to asthma and, in light of the new Phase II results, chronic sinusitis with nasal polyps.

The bull case for dupilumab lies both in its pan-allergic treatment potential and in the fact that the standard of care for each of its targets consists of corticosteroids, which can lead to unpleasant side effects and immune disruption. Those factors have Regeneron thinking big with the antibody, hoping it can win approval and blossom into a blockbuster.

"We have a lot of debate within the company as to which of our many programs is the most exciting, and a lot of people are voting on dupilumab," Regeneron Chief Scientific Officer George Yancopoulos told Reuters earlier this month.

- read the results