March 13 (Reuters) - France's Sanofi SA (SASY.PA) on Monday agreed to acquire Provention Bio Inc <PRVB.O> for $2.9 billion to bolster its work on a U.S.-approved type 1 diabetes therapy and strengthen its drug pipeline following development setbacks. The deal builds on an existing co-promotion agreement between the two companies, and would give the French drugmaker full ownership of the drug, Tzield, Sanofi said, adding it expects to complete the acquisition in the second quarter of 2023. While growth in asthma and eczema drug Dupixent is boosting Sanofi's sales, investors have criticised its drug development pipeline as weak. Sanofi, the maker of long acting insulin products Toujeo and Lantus for type 2 diabetes, in 2019 quit further type 2 diabetes drug development. Chief Executive Officer Paul Hudson said last month the company saw great promise in type 1 diabetes drug development and reaffirmed his commitment to steer clear of further work on type 2 diabetes and obesity.

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