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(Adds detail on drug's other uses, Sanofi investor day)
Nov 11 (Reuters) - An experimental biotech drug for moderateto severe asthma from France's Sanofi and its U.S.partner Regeneron has produced good results in clinicaltests, suggesting that its dual-action mechanism may be highlyeffective.
The encouraging data allows the companies to beginfinal-stage Phase III asthma trials on the medicine, which isalso being developed for atopic dermatitis and chronic sinusitiswith nasal polyps.
Dupilumab is one of the new medicines Sanofi is expecteddiscuss at an investor day on Nov. 20 - an event that will beovershadowed by uncertainties about the company's future afterthe summary dismissal of its chief executive.
Dupilumab is a latecomer among a new class of antibody drugsfor people whose asthma does not respond adequately to inhalers,but unlike rivals such as GlaxoSmithKline's mepolizumabit hits two targets at once.
In a mid-stage Phase IIb clinical study, dupilumab cutserious asthma attacks, known as exacerbations, by 64 to 75percent. The Sanofi drug works by blocking two key inflammatorychemicals that drive asthma, called IL-4 and IL-13.
Analysts believe that Sanofi's product could be launched in2019, putting it well behind GSK's drug, which is leading thepack and has already filed for regulatory approval.
Nevertheless, Berenberg Bank analyst Alistair Campbell saidthat dupilumab could still be a commercial success, withpotential annual sales of $1.5 billion by 2025, if the strongdata in current tests were replicated in final-stage Phase IIIstudies.
Other companies working on similar biotech asthma drugsinclude AstraZeneca, Roche and Teva.
(Reporting by Ben Hirschler; Editing by David Goodman)
