Why Sanofi Is Buying Kymab For Up To $1.45 Billion

By Noah Long ● January 13, 2021
  • Sanofi recently announced that it is going to buy Kymab. These are the details.

Sanofi recently announced that it is going to buy Kymab, a clinical-stage biopharmaceutical company developing fully human monoclonal antibodies with a focus on immune-mediated diseases and immuno-oncology therapeutics, in a deal valued at up to $1.45 billion. Through the deal, Sanofi will obtain the global rights to KY1005, which is a human monoclonal antibody.

This deal comes several months after Sanofi announced it is planning to spend $3.4 billion for Principia Biopharma. Principia Biopharma has developed BTK inhibitors for treating autoimmune disorders.

In August 2020, Kymab had announced that KY1005 met both primary endpoints in a Phase 2a trial studying moderate to severe atopic dermatitis patients whose disease is inadequately controlled with topical corticosteroids. And KY1005 demonstrated a consistent treatment effect versus placebo across various key endpoints, including in the Eczema Area and Severity Index (EASI) and additional objective clinical measures.

Kymab’s pipeline also includes the oncology asset KY1044, which is an ICOS agonist monoclonal antibody currently in early Phase 1/2 development as monotherapy and in combination with an anti-PD-L1. And the acquisition also provides Sanofi with access to new antibody technologies and research capabilities.

Terms Of The Deal

Under the terms of the deal, Sanofi will acquire Kymab for an upfront payment of approximately $1.1 billion and up to $350 million upon achievement of certain milestones. And Sanofi plans to finance the transaction with cash on hand. 

Sanofi expects to complete the acquisition in the first half of 2021. 


“The Kymab acquisition adds KY1005 to our dynamic pipeline, a potential first-in-class treatment for a range of immune and inflammatory diseases. The novel mechanism of action may provide treatment for patients with suboptimal responses to available therapies. We understand from our ongoing work in debilitating immunological diseases how critical it is to find the right treatment for each patient. We look forward to rapidly developing this investigational medicine.”

— Paul Hudson, Sanofi Chief Executive Officer

“The agreement is a testament to the commitment, drive and expertise of the entire Kymab team and we are pleased to receive this endorsement from Sanofi. With its significant global resources, we believe Sanofi is the perfect partner to progress Kymab’s pipeline of products and the merger will expedite the time it takes for our novel therapies to get to patients.”

— Simon Sturge, Chief Executive Officer, Kymab

“This acquisition aligns with our strategy of targeting fundamentally important disease pathways.  We believe that OX40L, a key immune regulator, has the potential to rebalance the immune system without suppressing it, providing a promising new approach to treating a range of immune-mediated diseases.” 

— John Reed, M.D. Ph.D., Global Head of Research & Development at Sanofi.