Sanofi Acquires Immune Disease Biotech in $3.7B Deal

Human B-cell (NIAID, Flickr)

17 Aug. 2020. A developer of small-molecule therapies for autoimmune diseases, including multiple sclerosis, and other immune disorders is being acquired by Sanofi. The Paris-based pharmaceutical company is buying Principia Biopharma Inc. in South San Francisco, California in a deal valued at $3.68 billion dollars.

Principia Biopharma discovers and develops new therapies with a technology called tailored covalency. Compounds in the company’s portfolio are designed to bind to specific cysteine amino acids in their targets. These amino acids have a binding action different from most others, says Principia, which allows the therapeutic payloads to break the bonds under certain conditions, making many of the company’s drugs highly targeted and reversible, with fewer adverse effects as a result.

Sanofi is no stranger to Principia. As reported by Science & Enterprise in November 2017, Sanofi licensed Principia’s candidate code-named PRN2246, a small-molecule, oral drug that blocks Bruton’s tyrosine kinase, or BTK enzymes. These enzymes are active in signaling pathways affecting B-cells in the immune system, particularly signals promoting autoimmunity. PRN2246, says Principia, can also penetrate the blood-brain barrier, a key property for treating multiple sclerosis, and while it inhibits signals from BTK enzymes to B-cells, it does not deplete the supply of these cells in the immune system.

In addition, says the company, PRN2246/SAR442168 — its code-name for both Sanofi and Principia, abbreviated as “168” — works in the peripheral nervous system, as well as the brain and spinal cord, making it a potential treatment for other neurological and inflammatory disorders. The experimental drug’s success in early and mid-stage clinical trials, as well as its potential with diseases other than multiple sclerosis, apparently attracted Sanofi’s attention.

“The Phase 2b data in relapsing multiple sclerosis showed the strong potential of ‘168 to address disability and disease progression,” says John Reed, head of R&D at Sanofi in a statement, “and triggered the start of Phase 3 studies across the full spectrum of MS. Through this acquisition, we will be able to expand and accelerate development of BTK inhibitors across multiple indications.”

Another Principia drug candidate of interest is rilzabrutinib, the company’s first BTK inhibitor, designed to treat the rare autoimmune disorders pemphigus and immune thrombocytopenia. Pemphigus causes blisters and sores on the skin and mucous membranes, which can rupture easily and become infected. Immune thrombocytopenia is a blood disorder where the body makes an unusually low number of platelets, and thus making blood difficult to clot, leading to excessive bruising and bleeding. Rilzabrutinib is in a late-stage clinical trial for pemphigus and mid-stage trial for immune thrombocytopenia.

Martin Babler, president and CEO at Principia adds, “The benefit of developing several BTK inhibitors will allow us to target specific organ systems for optimal patient benefit. The merger will provide global resources to get these novel therapies to patients faster.”

Sanofi is paying $3.68 billion, or $100 per share for Principia stock, which represents a 10 percent premium over the shares’ closing price of $90.74 on Friday.

More from Science & Enterprise:

• Start-Up to Engineer T-Cells for Autoimmune Diseases
• Engineered Immune, Stem Cells Studied for HIV Cure
• Start-Up Licenses Immunotherapies in $880M Deal
• Topical Immune Drug Reverses Skin Disease
• Genomics, A.I. Calculate Immune Health

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