VX-509 and EULAR 2012

There hasn’t been much on VX-509, a JAK 3 directed small molecule. Joel Kremer just told us that VX-509 is in study phase 2. Roy Fleischmann presented a study at the ACR 2011 in Chicago: “Dose Ranging Study of VX-509, An Oral Selective JAK3 Inhibitor, As Monotherapy in Patients with Active Rheumatoid Arthritis (RA)” (late breaking poster No.3, link: https://acr.confex.com/acr/2011/webprogram/Paper24549.html). Nothing new on this study at the EULAR meeting in Berlin.


[SP0169] JAK INHIBITION IN PATIENTS WITH RHEUMATOID ARTHRITIS
J. Kremer. Albany Medical College and The Center for Rheumato, Albany, United States
JAK inhibitors are small molecules with short half lives which can be administered orally in BID (CP-690,550; half life of 3 hrs) or QD dosing (INCBO28050; half life of 6 hrs). CP-690,550 has completed several phase III trials including use as: monotherapy; use with background DMARDs; and structure. INCBO18424, INCBO28050 and VX-509 are presently in Phase II.


The second study comes from I.M. Catlett and colleagues. They looked at biomarkes assessment of VX-509. They found that VX-509 reversibly inhibits JAK 3. So the drug warrants further clinical assessment, which is under way.


[THU0141] BIOMARKER ASSESSMENT OF VX-509, AN INVESTIGATIONAL SELECTIVE JAK3 INHIBITOR, IN HEALTHY VOLUNTEERS
I.M. Catlett, X. Luo, M.S. Penney, M.E. Pray, G. Spencer-Green, M. Botfield, T. Hoock. Vertex Pharmaceuticals Incorporated, Cambridge, United States
Conclusions: The PK/PD correlations of the experimental biomarkers demonstrated that VX-509 is a selective, reversible inhibitor of JAK3 signaling in humans. VX-509 warrants further clinical investigation in patients with chronic, immune-mediated inflammatory disorders, including rheumatoid arthritis.

So we have to wait for news on VX-509 until the ACR meeting 2012 in Washington.