Dual Inhibition of TYK2 and JAK1 for the Treatment of Autoimmune Diseases: Discovery of (( S)-2,2-Difluorocyclopropyl)((1 R,5 S)-3-(2-((1-methyl-1 H-pyrazol-4-yl)amino)pyrimidin-4-yl)-3,8-diazabicyclo[3.2.1]octan-8-yl)methanone (PF-06700841)

J Med Chem. 2018 Oct 11;61(19):8597-8612. doi: 10.1021/acs.jmedchem.8b00917. Epub 2018 Aug 16.


Cytokine signaling is an important characteristic of autoimmune diseases. Many pro-inflammatory cytokines signal through the Janus kinase (JAK)/Signal transducer and activator of transcription (STAT) pathway. JAK1 is important for the γ-common chain cytokines, interleukin (IL)-6, and type-I interferon (IFN) family, while TYK2 in addition to type-I IFN signaling also plays a role in IL-23 and IL-12 signaling. Intervention with monoclonal antibodies (mAbs) or JAK1 inhibitors has demonstrated efficacy in Phase III psoriasis, psoriatic arthritis, inflammatory bowel disease, and rheumatoid arthritis studies, leading to multiple drug approvals. We hypothesized that a dual JAK1/TYK2 inhibitor will provide additional efficacy, while managing risk by optimizing selectivity against JAK2 driven hematopoietic changes. Our program began with a conformationally constrained piperazinyl-pyrimidine Type 1 ATP site inhibitor, subsequent work led to the discovery of PF-06700841 (compound 23), which is in Phase II clinical development (NCT02969018, NCT02958865, NCT03395184, and NCT02974868).

Publication types

  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

  • Animals
  • Antitubercular Agents / pharmacology*
  • Arthritis, Experimental / chemically induced
  • Arthritis, Experimental / microbiology
  • Arthritis, Experimental / prevention & control*
  • Female
  • Janus Kinase 1 / antagonists & inhibitors*
  • Molecular Structure
  • Mycobacterium tuberculosis / drug effects*
  • Protein Kinase Inhibitors / pharmacology*
  • Pyrazoles / pharmacology*
  • Pyrimidines / pharmacology*
  • Rats
  • Rats, Inbred Lew
  • TYK2 Kinase / antagonists & inhibitors*
  • Tuberculosis / complications*
  • Tuberculosis / microbiology


  • Antitubercular Agents
  • Protein Kinase Inhibitors
  • Pyrazoles
  • Pyrimidines
  • PF-06700841
  • Janus Kinase 1
  • TYK2 Kinase

Associated data

  • ClinicalTrials.gov/NCT02969018
  • ClinicalTrials.gov/NCT02958865
  • ClinicalTrials.gov/NCT03395184
  • ClinicalTrials.gov/NCT02974868