Sanofi paid $2.9bn for Tzield and its developer Provention earlier this year, but a mixed readout in its key Phase III study will raise doubts among analysts about its long-term prospects in later-stage patients.

The US firm’s multi-billion dollar buyout of the rare disease biotech Reata was not so straightforward according to a recent security filing that detailed a back-and-forth bidding process between Biogen and a rival company that initiated first contact, believed to be Sanofi.

French pharma gets global rights at the start of Phase II for the US biotech’s preclinical program for inhibiting the STAT6 protein in respiratory and dermatologic disorders.

Almost 80% of novel agent submissions from the biggest companies were approved in recent years, compared with a 60% approval rate for the rest of the industry, according to a recent analysis of FDA approval decisions since 2021.