Tumor necrosis factor (TNF) is a pleiotropic cytokine belonging to a family of trimeric proteins with both proinflammatory and immunoregulatory functions. TNF is a key mediator in autoimmune diseases and during the last couple of decades several biologic drugs have delivered new therapeutic options for patients suffering from chronic autoimmune diseases such as rheumatoid arthritis and chronic inflammatory bowel disease. Attempts to design small molecule therapies directed to this cytokine have not led to approved products yet. Here we report the discovery and development of a potent small molecule inhibitor of TNF that was recently moved into phase 1 clinical trials. The molecule, SAR441566, stabilizes an asymmetrical form of the soluble TNF trimer, compromises downstream signaling and inhibits the functions of TNF in vitro and in vivo. With SAR441566 being studied in healthy volunteers we hope to deliver a more convenient orally bioavailable and effective treatment option for patients suffering with chronic autoimmune diseases compared to established biologic drugs targeting TNF.

In recent years, spirocycles have been the focus of medicinal chemistry, and several drugs or drug candidates incorporating these “non-planar” chemical motifs have been developed. New advancements in this field, however, are greatly limited by the lack of innovative methods enabling the preparation of original spirocyclic cores. Here-in, an unprecedented intramolecular Buchwald-Hartwig N-arylation of bicyclic hydrazines is described. This key reaction gives access to unique spiro[indoline-2,3'-piperidine] derivatives after reductive cleavage of the nitro-gen–nitrogen bond. This approach widens the chemical space of spirocycles and may reveal useful to explore new avenues of research in drug discovery.