C₁₅H₁₉N₅O, 285.34, UNII-2OYE00PC25
CAS: 2140301-97-7 (malonate)
Chemical Formula: C18H23N5O5
Molecular Weight: 389.412
PHASE 2 alopecia areata, rheumatoid arthritis, Crohn’s disease, and ulcerative colitis.
PF-06651600 is a potent and selective JAK3 inhibitor. PF-06651600 is a potent and low clearance compound with demonstrated in vivo efficacy. The favorable efficacy and safety profile of this JAK3-specific inhibitor PF-06651600 led to its evaluation in several human clinical studies. JAK3 was among the first of the JAKs targeted for therapeutic intervention due to the strong validation provided by human SCID patients displaying JAK3 deficiencies
Pfizer has established a leading kinase research capability with multiple unique kinase inhibitors in development as potential medicines. PF-06651600 is a highly selective and orally bioavailable Janus Kinase 3 (JAK3) inhibitor that represents a potential immunomodulatory therapy. With the favorable efficacy, safety profile, and ADME properties, this JAK3-specific covalent inhibitor has been under clinical investigation for the treatment of alopecia areata, rheumatoid arthritis, Crohn’s disease, and ulcerative colitis. Supported by positive results from a Phase 2 study, 1 was granted Breakthrough Therapy designation by the FDA on Sept. 5, 2018 for treatment of alopecia areata.
J. Med. Chem. 2017, 60 (5), 1971–1993, DOI: 10.1021/acs.jmedchem.6b01694
Process Development and Scale Up of a Selective JAK3 Covalent Inhibitor PF-06651600,
A scalable process for PF-06651600 (1) has been developed through successful enabling of the first generation syntheis. The synthesis highlights include the following: (1) replacement of costly PtO2 with a less expensive 5% Rh/C catalyst for a pyridine hydrogenation, (2) identification of a diasteroemeric salt crystallization to isolate the enantiomerically pure cis-isomer directly from a racemic mixture of cis/trans isomers, (3) a high yielding amidation via Schotten–Baumann conditions, and (4) critical development of a reproducible crystallization procedure for a stable crystalline salt (1·TsOH), which is suitable for long-term storage and tablet formulation. All chromatographic purifications, including two chiral SFC chromatographic separations, were eliminated. Combined with other improvements in each step of the synthesis, the overall yield was increased from 5% to 14%. Several multikilogram batches of the API have been delivered to support clinical studies.
1-((2S,5R)-5-((7H-Pyrrolo[2,3-d]pyrimidin-4-yl)amino)-2-methylpiperidin-1-yl)prop-2-en-1-one p-Toluenesulfonate (1·TsOH)
1·TsOH (4.41 kg, 9.64 mol) as a white powder in 89.6% yield (accounting for the amount of seed charged). Achiral HPLC purity: 99.6% with 0.22% of dimer 15. Chiral SFC purity: >99.7%. Mp 199 °C. Rotomers observed for NMR spectroscopies. 1H NMR (400 MHz, DMSO-d6): δ ppm 12.68 (brs, 1H), 9.22 (brs, 1H), 8.40 (s, 1H), 7.50 (d, J = 8.2 Hz, 2H), 7.45 (m, 1H), 7.12 (d, J = 8.2 Hz, 2H), 6.94 (d, J = 1.2 Hz, 1H), 6.84 (m, 1H), 6.13 (m, 1H), 5.70 (m, 1H), 4.81 (m, 0.5H), 4.54 (m, 0.5H), 4.41 (m, 0.5H), 4.12 (m, 0.5H), 3.99 (m, 1H), 3.15 (m, 0.5H), 2.82 (m, 0.5H), 2.29 (s, 3H), 1.91–1.72 (m, 4H), 1.24–1.17 (m, 3H). 13C NMR (100 MHz, DMSO-d6): δ ppm 165.52, 165.13, 150.50, 145.64, 143.06, 138.48, 129.51, 129.24, 128.67, 127.99, 127.73, 125.97, 125.02, 102.30, 49.53, 48.92, 47.27, 43.83, 42.96, 29.37, 28.41, 25.22, 21.28, 16.97, 15.51. HRMS (ESI) m/z: calculated for C15H20N5O [M + H]+286.1668; observed 286.1692.
Telliez JB, et al. Discovery of a JAK3-Selective Inhibitor: Functional Differentiation of JAK3-Selective Inhibition over pan-JAK or JAK1-Selective Inhibition. ACS Chem Biol. 2016 Dec 16;11(12):3442-3451.
1: D’Amico F, Fiorino G, Furfaro F, Allocca M, Danese S. Janus kinase inhibitors for the treatment of inflammatory bowel diseases: developments from phase I and phase II clinical trials. Expert Opin Investig Drugs. 2018 Jul;27(7):595-599. doi: 10.1080/13543784.2018.1492547. Epub 2018 Jul 6. Review. PubMed PMID: 29938545.
2: Robinette ML, Cella M, Telliez JB, Ulland TK, Barrow AD, Capuder K, Gilfillan S, Lin LL, Notarangelo LD, Colonna M. Jak3 deficiency blocks innate lymphoid cell development. Mucosal Immunol. 2018 Jan;11(1):50-60. doi: 10.1038/mi.2017.38. Epub 2017 May 17. PubMed PMID: 28513593; PubMed Central PMCID: PMC5693788.
3: Thorarensen A, Dowty ME, Banker ME, Juba B, Jussif J, Lin T, Vincent F, Czerwinski RM, Casimiro-Garcia A, Unwalla R, Trujillo JI, Liang S, Balbo P, Che Y, Gilbert AM, Brown MF, Hayward M, Montgomery J, Leung L, Yang X, Soucy S, Hegen M, Coe J, Langille J, Vajdos F, Chrencik J, Telliez JB. Design of a Janus Kinase 3 (JAK3) Specific Inhibitor 1-((2S,5R)-5-((7H-Pyrrolo[2,3-d]pyrimidin-4-yl)amino)-2-methylpiperidin-1-yl)prop -2-en-1-one (PF-06651600) Allowing for the Interrogation of JAK3 Signaling in Humans. J Med Chem. 2017 Mar 9;60(5):1971-1993. doi: 10.1021/acs.jmedchem.6b01694. Epub 2017 Feb 16. PubMed PMID: 28139931.
4: Telliez JB, Dowty ME, Wang L, Jussif J, Lin T, Li L, Moy E, Balbo P, Li W, Zhao Y, Crouse K, Dickinson C, Symanowicz P, Hegen M, Banker ME, Vincent F, Unwalla R, Liang S, Gilbert AM, Brown MF, Hayward M, Montgomery J, Yang X, Bauman J, Trujillo JI, Casimiro-Garcia A, Vajdos FF, Leung L, Geoghegan KF, Quazi A, Xuan D, Jones L, Hett E, Wright K, Clark JD, Thorarensen A. Discovery of a JAK3-Selective Inhibitor: Functional Differentiation of JAK3-Selective Inhibition over pan-JAK or JAK1-Selective Inhibition. ACS Chem Biol. 2016 Dec 16;11(12):3442-3451. Epub 2016 Nov 10. PubMed PMID: 27791347.
5: Walker G, Croasdell G. The European League Against Rheumatism (EULAR) – 17th Annual European Congress of Rheumatology (June 8-11, 2016 – London, UK). Drugs Today (Barc). 2016 Jun;52(6):355-60. doi: 10.1358/dot.2016.52.6.2516435. PubMed PMID: 27458612.
////////////PF-06651600, PF 06651600, PF06651600, Breakthrough Therapy designation, PHASE 2, alopecia areata, rheumatoid arthritis, Crohn’s disease, ulcerative colitis,