JAK Inhibitor (jak + inhibitor)

Distribution by Scientific Domains


Selected Abstracts


The safety and efficacy of a JAK inhibitor in patients with active rheumatoid arthritis: Results of a double-blind, placebo-controlled phase IIa trial of three dosage levels of CP-690,550 versus placebo,,

ARTHRITIS & RHEUMATISM, Issue 7 2009
Joel M. Kremer
Objective To determine the efficacy, safety, and tolerability of 3 different dosages of CP-690,550, a potent, orally active JAK inhibitor, in patients with active rheumatoid arthritis (RA) in whom methotrexate, etanercept, infliximab, or adalimumab caused an inadequate or toxic response. Methods Patients (n = 264) were randomized equally to receive placebo, 5 mg of CP-690,550, 15 mg of CP-690,550, or 30 mg of CP-690,550 twice daily for 6 weeks, and were followed up for an additional 6 weeks after treatment. The primary efficacy end point was the American College of Rheumatology 20% improvement criteria (ACR20) response rate at 6 weeks. Results By week 6, the ACR20 response rates were 70.5%, 81.2%, and 76.8% in the 5 mg, 15 mg, and 30 mg twice daily groups, respectively, compared with 29.2% in the placebo group (P < 0.001). Improvements in disease activity in CP-690,550,treated patients compared with placebo were seen in all treatment groups as early as week 1. ACR50 and ACR70 response rates significantly improved in all treatment groups by week 4. The most common adverse events reported were headache and nausea. The infection rate in both the 15 mg twice daily group and the 30 mg twice daily group was 30.4% (versus 26.2% in the placebo group). No opportunistic infections or deaths occurred. Increases in mean low-density lipoprotein cholesterol and high-density lipoprotein cholesterol levels, and increases in mean serum creatinine level (0.04,0.06 mg/dl) were seen in all CP-690,550 treatment arms. Conclusion Our findings indicate that CP-690,550 is efficacious in the treatment of RA, resulting in rapid, statistically significant, and clinically meaningful reductions in the signs and symptoms of RA. Further studies of CP-690,550 in RA are warranted. [source]


Co-administration of the JAK inhibitor CP-690,550 and methotrexate is well tolerated in patients with rheumatoid arthritis without need for dose adjustment

BRITISH JOURNAL OF CLINICAL PHARMACOLOGY, Issue 2 2010
Stanley Cohen
WHAT IS ALREADY KNOWN ABOUT THIS SUBJECT , CP-690,550 is a novel JAK inhibitor in development as a therapy for rheumatoid arthritis. , Methotrexate is the cornerstone of combination treatment for rheumatoid arthritis. , The safety and tolerability of co-administration of CP-690,550 with methotrexate have not been addressed to date. WHAT THIS STUDY ADDS , This study in patients with rheumatoid arthritis shows that there are no clinically relevant effects on the pharmacokinetics of either drug following short-term co-administration. , Co-administration of CP-690,550 and methotrexate was safe and well tolerated. AIMS To investigate the effects of methotrexate (MTX) on the pharmacokinetics (PK) of CP-690,550, a novel Janus kinase (JAK) inhibitor in development as a therapy for rheumatoid arthritis (RA), to determine the effects of multiple doses of CP-690,550 on the PK of MTX, and to evaluate the short-term safety and tolerability of co-administration of CP-690,550 and MTX. METHODS This was a fixed-dose drug,drug interaction study. Twelve patients diagnosed with RA for at least 6 months were enrolled in a Phase I, open-label study of the PK of multiple doses of CP-690,550 (30 mg b.i.d.) and single doses of MTX (15,25 mg per week). RESULTS All patients completed the study and were evaluated for PK and safety. CP-690,550 exposure was not affected by co-administration with MTX; AUC12 ratio (CP-690,550 + MTX/CP-690,550) was 103.06% [90% confidence interval (CI) 99.00, 107.29]. MTX exposure decreased by 10%; AUC12 ratio (CP-690,550 + MTX/MTX) was 89.53% (90% CI 77.38, 103.57), which was not considered clinically significant. Co-administration of CP-690,550 and MTX was safe and well tolerated. There were no serious adverse events or withdrawals from the study and there was no trend in the incidence or severity of adverse events across treatments. CONCLUSIONS Co-administration of CP-690,550 and MTX was safe and well tolerated. There was no clinically significant effect on the PK profile of either drug. Therefore, dose adjustments should not be required when co-administering CP-690,550 and MTX. [source]


Interleukin-4 and interleukin-13 enhance CCL26 production in a human keratinocyte cell line, HaCaT cells

CLINICAL & EXPERIMENTAL IMMUNOLOGY, Issue 3 2005
S. Kagami
Summary Eotaxin-2/CCL24 and eotaxin-3/CCL26 are CC chemokines and their receptor, CC chemokine receptor 3 is preferentially expressed on eosinophils. It was reported that vascular endothelial cells and dermal fibroblasts produced CCL26. However, the regulation of CCL24 and CCL26 production in keratinocytes has not been well documented. We investigated the expression and production of CCL24 and CCL26 in the human keratinocyte cell line, HaCaT cells. Reverse transcription and polymerase chain reaction was performed using these cells and Enzyme-linked immunosorbent assay was carried out using supernatant of these cells. The production of CCL24 in HaCaT cells was slightly enhanced by IL-4 and that of CCL26 was strongly enhanced by IL-4 and IL-13. Furthermore, TNF-, generated a synergistic effect on IL-4 enhanced CCL26 production. Dexamethasone, IFN-, and the p38 mitogen-activated protein kinase inhibitor SB202190 inhibited IL-4 enhanced CCL26 production. IL-4 enhanced production of CCL26 was inhibited by leflunomide and JAK inhibitor 1, but not by JAK3 inhibitor, which indicates that it is mediated by JAK1-STAT6-dependent pathway. This result also strongly suggests the involvement of the type 2 IL-4 receptor in IL-4 enhanced production of CCL26. These results suggest that keratinocytes are involved in the migration of CC chemokine receptor 3 positive cells such as eosinophils in a Th2-dominant situation like atopic dermatitis. [source]


Treatment options for hydroxyurea-refractory disease complications in myeloproliferative neoplasms: JAK2 inhibitors, radiotherapy, splenectomy and transjugular intrahepatic portosystemic shunt

EUROPEAN JOURNAL OF HAEMATOLOGY, Issue 3 2010
Elena Mishchenko
Abstract Clinical care of patients with polycythemia vera, essential thrombocythemia and myelofibrosis (MF) requires not only a broad understanding of general treatment principles but also familiarity with the management of hydroxyurea-refractory disease complications. The latter include progressive splenomegaly, symptomatic portal hypertension (e.g. ascites, variceal bleeding), pulmonary hypertension, bone pain, intractable pruritus, constitutional symptoms (e.g. fatigue, night sweats) and cachexia (i.e. loss of lean body mass, general ill health, poor appetite). Some of these symptoms are directly or indirectly related to extramedullary hematopoiesis (EMH) and others to proinflammatory cytokine excess. Results from recent clinical trials of JAK inhibitors suggest remarkable activity in MF-associated constitutional symptoms, cachexia, pruritus and hydroxyurea-refractory splenomegaly. Involved-field radiotherapy is best utilized in the setting of EMH-associated symptoms, including ascites, bone (extremity) pain and pulmonary hypertension. Splenectomy is indicated in the presence of drug-refractory splenomegaly and frequent red cell transfusion requirement. Transjugular intrahepatic portosystemic shunt is used to alleviate symptoms of portal hypertension. [source]