Nimbus raises $105M for multifront TYK2 clinical trial program

Nimbus Therapeutics has raised $105 million to put its allosteric TYK2 inhibitor through a clutch of phase 2 clinical trials. The multifront midphase program is designed to determine whether the drug has a future in a range of autoimmune and inflammatory diseases potentially amenable to TYK2 inhibition. 

TYK2 is part of the JAK family. Approved JAK inhibitors such as Eli Lilly’s Olumiant and AbbVie’s Rinvoq have improved outcomes in diseases including rheumatoid arthritis. However, the FDA has lumbered the class of medicines with black box warnings over increased risk of serious infections, malignancy and thrombosis. Selective inhibition of TYK2 could deliver a better risk-benefit profile.

A syndicate of investors led by BVF Partners has come together to help Nimbus find out if its prospect lives up to that promise. Equipped with cash from new and existing investors including RA Capital Management, Atlas Venture, Access Biotechnology and Commodore Capital, Nimbus plans to start multiple phase 2 studies in 2021 and 2022. Nimbus CEO Jeb Keiper said the trials will “elucidate the full range of potential patient benefit from this novel therapeutic.”

Bristol Myers Squibb has laid down a marker for the potential of TYK2 inhibitors over the past year with the delivery of phase 3 data on deucravacitinib in psoriasis. Armed with the data, Bristol Myers plans to seek FDA approval for a drug it has tipped to generate annual sales of $4 billion.

The excitement about TYK2 inhibitors reflects the potential for the molecules to treat a wide range of diseases. Bristol Myers is studying deucravacitinib in indications including lupus nephritis, psoriatic arthritis, systemic lupus erythematosus and ulcerative colitis. With $105 million in fresh funding, Nimbus has the means to explore the potential of its rival molecule. Bristol Myers gained an option to acquire Nimbus’ TYK2 program through its takeover of Celgene. 

Nimbus will have enough money left over from the phase 2 work to fund a first-in-human clinical trial of its HPK1 inhibitor in solid tumor patients. The study, which Nimbus plans to start this year, will provide early evidence of the effects of hitting the intracellular negative regulator of T-cell proliferation. Nimbus plans to start IND-enabling studies on two other novel agents next year.