A pharmacokinetic and clinical assessment of tofacitinib for the treatment of rheumatoid arthritis

Effect of P. corylifolia on the pharmacokinetic profile of tofacitinib and the underlying mechanism

This work aimed to explore the mechanisms underlying the interaction of the active furanocoumarins in P. corylifolia on tofacitinib both in vivo and in vitro. The concentration of tofacitinib and its metabolite M8 was determined using UPLC-MS/MS. The peak area ratio of M8 to tofacitinib was calculated to compare the inhibitory ability of furanocoumarin contained in the traditional Chinese medicine P. corylifolia in rat liver microsomes (RLMs), human liver microsomes (HLMs) and recombinant human CYP3A4 (rCYP3A4). We found that bergapten and isopsoralen exhibited more significant inhibitory activity in RLMs than other furanocoumarins. Bergapten and isopsoralen were selected to investigate tofacitinib drug interactions in vitro and in vivo. Thirty rats were randomly allocated into 5 groups (n = 6): control (0.5% CMC-Na), low-dose bergapten (20 mg/kg), high-dose bergapten (50 mg/kg), low-dose isopsoralen (20 mg/kg) and ketoconazole. 10 mg/kg of tofacitinib was orally intervented to each rat and the concentration level of tofacitinib in the rats were determined by UPLC-MS/MS. More imporrantly, the results showed that bergapten and isopsoralen significantly inhibited the metabolism of tofacitinib metabolism. The AUC(0-t), AUC(0-∞), MRT(0-t), MRT(0-∞) and Cmax of tofacitinib increased in varying degrees compared with the control group (all p < 0.05), but CLz/F decreased in varying degrees (p < 0.05) in the different dose bergapten group and isopsoralen group. Bergapten, isopsoralen and tofacitinib exhibit similar binding capacities with CYP3A4 by AutoDock 4.2 software, confirming that they compete for tofacitinib metabolism. P. corylifolia may considerably impact the metabolism of tofacitinib, which can provide essential information for the accurate therapeutic application of tofacitinib.

Hair Growth Effect of DN106212 in C57BL/6 Mouse and Its Network Pharmacological Mechanism of Action

Centipeda minima (CMX) has been widely investigated using network pharmacology and clinical studies for its effects on hair growth via the JAK/STAT signaling pathway. Human hair follicle papilla cells exhibit hair regrowth through the expression of Wnt signaling-related proteins. However, the mechanism of action of CMX in animals has not been elucidated fully. This study examined the effect of induced hair loss and its side-effects on the skin, and observed the mechanism of action of an alcoholic extract of CMX (DN106212) on C57BL/6 mice. Our results showed that DN106212 was more effective in promoting hair growth than dimethyl sulfoxide in the negative control and tofacitinib (TF) in the positive control when mice were treated with DN106212 for 16 days. We confirmed that DN106212 promotes the formation of mature hair follicles through hematoxylin and eosin staining. We also found that the expression of vascular endothelial growth factor (Vegfa), insulin-like growth factor 1 (Igf1), and transforming growth factor beta 1 (Tgfb1) is related to hair growth using PCR. DN106212-treated mice had significantly higher expression of Vegfa and Igf1 than TF-treated ones, and inhibiting the expression of Tgfb1 had similar effects as TF treatment. In conclusion, we propose that DN106212 increases the expression of hair growth factors, promotes the development of hair follicles, and promotes hair growth. Although additional experiments are needed, DN106212 may serve as an experimental basis for research on natural hair growth-promoting agents.

Therapeutics in rheumatology and the kidney

The field of rheumatology has advanced significantly in recent years to provide rheumatologists with an extensive array of medications to combat rheumatic joint conditions. In contrast to an older era, when NSAIDs and other nephrotoxic agents were the mainstay of treatment, modern DMARDs vary considerably in their nephrotoxic potential and their use is not always precluded in populations with pre-existing chronic kidney disease (CKD). This review will explore in detail the safety and efficacy profiles of medications used to treat rheumatologic disease, specifically in the setting of CKD. Specifically, we discuss both traditional agents used, i.e. NSAIDs, CSs and conventional synthetic DMARDs, as well as novel biologic DMARDs and targeted synthetic DMARDs. Anti-gout prescribing in CKD is also reviewed. We aim to provide practical guidance to rheumatologists, nephrologists and general physicians when prescribing these medications in the setting of CKD.

Mass balance study of [14C]SHR0302, a selective and potent JAK1 inhibitor in humans

SHR0302, a selective JAK1 inhibitor developed by Jiangsu Hengrui Pharmaceutical Co., was intended for the treatment of rheumatoid arthritis. In this study, we evaluated the pharmacokinetics, mass balance, and metabolism of SHR0302 in six healthy Chinese male subjects after a single 8 mg (80 µCi) oral dose of [¹⁴C]SHR0302.SHR0302 was absorbed rapidly (T_max = 0.505 h), and the average t_1/2 of the SHR0302-related components in plasma was approximately 9.18 h. After an oral dose was administered, the average cumulative excretion of the radioactive components was 100.56% ± 1.51%, including 60.95% ± 11.62% in urine and 39.61% ± 10.52% in faeces.A total of 16 metabolites were identified. In plasma, the parent drug SHR0302 accounted for 90.42% of the total plasma radioactivity. In urine, SHR161279 was the main metabolite, accounting for 33.61% of the dose, whereas the parent drug SHR0302 only accounted for 5.1% of the dose. In faeces, the parent drug SHR0302 accounted for 23.73% of the dose, and SHR161279 was the significant metabolite, accounting for 5.67% of the dose. In conclusion, SHR0302-related radioactivity was mainly excreted through urine (60.95%) and secondarily through faeces (39.61%).The metabolic reaction of SHR0302 in the human body is mainly through mono-oxidation and glucuronidation. The main metabolic location of SHR0302 in the human body is the pyrrolopyrimidine ring.

Effects of Isosakuranetin on Pharmacokinetic Changes of Tofacitinib in Rats with N-Dimethylnitrosamine-Induced Liver Cirrhosis

Tofacitinib, a Janus kinase 1 and 3 inhibitor, is used to treat rheumatoid arthritis. It is mainly metabolized by the cytochromes p450 (CYP) 3A1/2 and CYP2C11 in the liver. Chronic inflammation eventually leads to cirrhosis in patients with rheumatoid arthritis. Isosakuranetin (ISN), a component of Citrus aurantium L., has hepatoprotective effects in rats. This study was performed to determine the effects of ISN on the pharmacokinetics of tofacitinib in rats with N-dimethylnitrosamine-induced liver cirrhosis (LC). After intravenous administration of 10 mg/kg tofacitinib to control (CON), LC, and LC treated with ISN (LC-ISN) rats, the total area under the plasma concentration-time curves (AUC) from time zero to infinity increased by 158% in LC rats compared to those in CON rats; however, the AUC of LC-ISN rats decreased by 35.1% compared to that of LC rat. Similar patterns of AUC changes were observed in the LC and LC-ISN rats after oral administration of 20 mg/kg tofacitinib. These results can be attributed to decreased non-renal clearance (CL_NR) and intestinal intrinsic clearance (CL_int) in the LC rats and increased intestinal and hepatic CL_int in the LC-ISN rats. Our findings imply that ISN treatment in LC rats restored the decrease in either CL_NR or CL_int, or both, through increased hepatic and intestinal expression of CYP3A1/2 and CYP2C11, which is regulated by the induction of pregnane X receptor (PXR) and constitutive androstane receptor (CAR).

Bridging Efficacy of Tofacitinib Immediate-Release to Extended-Release Formulations for Treatment of Ulcerative Colitis: Application of a Model-Informed Drug Development Approach

Tofacitinib is an oral, small molecule Janus kinase inhibitor for the treatment of ulcerative colitis (UC). We report a model‐informed drug development approach for bridging efficacy from immediate‐release (IR) to extended‐release (XR) tofacitinib formulations in patients with UC. IR‐XR efficacy bridging was supported by exposure‐response analysis of phase 3 induction/maintenance studies of the IR formulation in UC to identify exposure metrics relevant for efficacy. Pharmacokinetic studies in healthy subjects were used to confirm similarity of relevant exposure metrics of tofacitinib IR 5 mg twice daily to XR 11 mg once daily, and tofacitinib IR 10 mg twice daily to XR 22 mg once daily, thereby bridging efficacy between IR and XR formulations. Food effect was evaluated at both XR formulation dose levels. Exposure‐response analysis demonstrated that area under the plasma concentration–time curve (average plasma concentration) was a relevant predictor of efficacy. Pharmacokinetic studies demonstrated that area under the plasma concentration–time curve was equivalent between formulations under single‐dose and steady‐state conditions, and other exposure metrics were also similar. These results also supported bridging of safety data for IR‐XR formulations. Food had no impact on tofacitinib XR exposure. These data support efficacy/safety bridging of IR‐XR formulations in patients with UC.

PK, PD, and interactions: the new scenario with JAK inhibitors and S1P receptor modulators, two classes of small molecule drugs, in IBD

INTRODUCTION

Inflammatory bowel diseases (IBDs) are immune-mediated chronic inflammatory disorders of the gastrointestinal tract whose pathogenesis is not yet fully understood. Despite the advent of biological agents, there are still unmet needs for IBD patients, due to suboptimal rate of sustained remission achieved. Small molecule drugs (SMDs), the next generation of selective drugs in IBD, show promising results in ongoing trials.

AREAS COVERED

We describe the pharmacodynamics and pharmacokinetic features of novel SMDs and their main differences with biologic agents.

EXPERT OPINION

Small molecule drugs are a promising class of drugs for the treatment of ulcerative colitis and Crohn's disease with good results in inducing and maintaining remission. Hence, over the next few years physicians will have numerous options of small molecule drugs for the treatment of patients with IBD. This group of drugs are potentially easier to use over biological agents due to pharmacokinetic features such as oral administration, short half-life, high volume of distribution, and lack of immunogenicity. On the other hand, drug-drug interactions can happen with small-molecule drugs, principally due to competitive metabolic and clearance mechanisms.

Design, synthesis and evaluation of (R)-3-(7-(methyl(7H-pyrrolo[2,3-d]pyrimidin-4-yl)amino)-5-azaspiro[2.4]heptan-5-yl)-3-oxopropanenitrile as a JAK1-selective inhibitor

Based on (R)-N-methyl-N-(5-azaspiro[2.4]heptan-7-yl)-7H-pyrrolo[2,3-d]pyrimidin-4-amine as a core scaffold, we identified (R)-3-(7-(methyl(7H-pyrrolo[2,3-d]pyrimidin-4-yl)amino)-5-azaspiro[2.4]heptan-5-yl)-3-oxopropanenitrile [(R)-6c] as a JAK1 selective inhibitor. The structural design was based on the combination of tofacitinib's 7-deazapurine and 5-azaspiro[2.4]heptan-7-amine. Compound (R)-6c exhibited an IC50 value of 8.5 nM against JAK1 with a selectivity index of 48 over JAK2. To optimize (R)-6c as a lead compound, we performed in vitro ADME, hERG, kinase profiling, and pharmacokinetic tests. Mouse and rat in vivo studies verified that (R)-6c exhibited desired efficacies in CIA and AIA models.

Emerging treatments for ulcerative colitis: a systematic review

OBJECTIVES

Various investigational medicinal products have been developed for ulcerative colitis (UC). Our aim was to systematically evaluate novel pharmacological therapeutic agents for the treatment of UC.

MATERIAL AND METHODS

Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) recommendations were followed. A search of the medical literature was conducted in the MEDLINE database for original research papers published between 01 January 2010 and 31 October 2014.

RESULTS

Twenty one studies, including 11,524 adults were analyzed. Thirteen different novel therapeutic drug options were identified. Vedolizumab and golimumab were superior to placebo as induction and maintenance therapy. Tofacitinib showed dose related efficacy for induction therapy. Etrolizumab showed higher clinical remission rates compared to placebo. Phosphatidylcholine led to an improved clinical activity index. HMPL-004 may become a mesalamine alternative for mild to moderate UC. PF00547,659 was well tolerated. Statins were not beneficial for acute exacerbations of UC. Abatacept, rituximab and visilizumab did not lead to improved outcomes compared to placebo. Higher concentration of BMS 936557 was associated with improved efficacy compared to placebo. Basiliximab did not enhance corticosteroid efficacy.

CONCLUSIONS

Patients with UC might achieve clinical response or remission by utilizing some of these agents with a favorable side effect profile. Further studies are needed to evaluate their short- and long-term efficacy and safety.

Bortezomib followed by autologous stem cell transplantation in a patient with rheumatoid arthritis: A case report and review of the literature

RATIONALE AND PATIENTS CONCERNS

Despite the introduction of varied disease-modifying antirheumatic drugs and biological agents, a substantial proportion of patients remain untreatable. We report a 56-year-old Chinese female patient with a case of refractory rheumatoid arthritis (RA) complicated with multiple myeloma (MM) who was treated successfully with Bortezomib followed by autologous stem cell transplantation (ASCT).

DIAGNOSIS AND INTERVENTIONS

We report a 56-year-old Chinese female patient who was diagnosed as RA complicating with MM. She received 4 cycles of Bortezomib-based chemotherapy followed by ASCT. The response of her RA and MM were evaluated after every cycle of Bortezomib-based chemotherapy.

INTERVENTIONS AND OUTCOMES

After the first Bortezomib-based chemotherapy cycle, this patient's symptoms were significantly alleviated and thereafter the RA activity continued to improve. After the 4 courses of Bortezomib-based chemotherapy, the C-reactive protein was <0.5 mg/dL and the disease activity score 28-erythrocyte sedimentation rate was 2.0. No hematological or nonhematological side effects were observed during the treatment of Bortezomib.

LESSONS

Bortezomib might be a new safe and promising drug for refractory RA patients.

Single- and multiple-dose pharmacokinetics of tofacitinib in healthy Chinese volunteers

Tofacitinib is an oral Janus kinase inhibitor. The objective of this phase 1, open-label study was to characterize the single- and multiple-dose pharmacokinetics (PK) of tofacitinib in 12 healthy, adult Chinese volunteers. Eligible subjects received oral tofacitinib 10 mg once daily on days 1 and 6 and twice daily on days 2-5. Blood samples were collected on day 1 predose and over 24 hours postdose (day 2 predose), predose on days 3-6, and over 12 hours postdose on day 6. PK parameters were calculated using noncompartmental analysis. Mean concentration-time profiles for days 1 and 6 were similar, with median time to peak concentration of 0.5 hours on both days. Plasma concentrations declined rapidly following attainment of peak concentrations, with a mean terminal half-life of 3.3 hours on day 1 (single dose) and 2.5 hours on day 6 (multiple dose). No accumulation in plasma occurred with twice-daily administration: accumulation ratio of 1.04. The rapid absorption, elimination, and systemic exposures (peak and area under the concentration-time curve) observed in healthy Chinese volunteers in this study are similar to those previously reported in white subjects.

Analysis of patents on anti-rheumatoid arthritis therapies issued in China

INTRODUCTION

The etiology of rheumatoid arthritis (RA) is complex and diverse. Chronic inflammatory processes with joint dysfunction can cause permanent disability. Therefore, the development of new drugs and therapies for RA is very important.

AREAS COVERED

This review analyzes the existing patents on anti-RA products in China to help pharmaceutical companies and individuals patent potential candidate drugs for RA treatment.

EXPERT OPINION

Three hundred and seventeen patents were analyzed, including 172 patents for Traditional Chinese Medicines (TCMs, 54.2%), 65 for synthetic compounds (20.5%), 55 for biological products (17.4%) and 25 patents for the drug preparation process (7.9%). Among the TCM patents, 73.8% were of various preparations for different Chinese medicines, 23.8% were of herbal extracts and 2.3% were of herbal extract derivatives. Synthetic compounds were involved in more than 30 targets, some small-molecule drugs that target signaling kinases such as p38 MAPK, Janus kinase may become important directions in the management of RA. Biological disease-modifying antirheumatic drugs (bDMARDs) are the most efficacious drugs for RA treatment. As the classic therapeutic target in RA, TNF-α has the largest number of bDMARD patents. In addition, it is expected that new targets such as high-mobility group protein B1, thioredoxin domain-containing protein 5 (TXNDC5) and B lymphocyte stimulator (BlyS) will play a significant role in RA as potential targets for new treatments. The largest number of all the published patent applications are claiming TCMs, which may provide substantial new information for anti-RA drug development. The largest number of all the published patent applications are claiming TCMs, which may provide huge information for anti-RA drug development.

Efficacy and safety of tofacitinib for treatment of rheumatoid arthritis

Tofacitinib is the first in a new class of nonbiologic disease-modifying antirheumatic drugs (DMARDs), a targeted, synthetic DMARD, approved for the treatment of rheumatoid arthritis (RA) as monotherapy or in combination with methotrexate or other non-biologic DMARD. Tofacitinib, an orally administered Janus kinase (JAK) inhibitor, decreases T-cell activation, pro-inflammatory cytokine production, and cytokine signaling by inhibiting binding of type I cytokine receptors family and γ-chain cytokines to paired JAK1/JAK3 receptors. The net effect of tofacitinb’s mechanism of action is decreased synovial inflammation and structural joint damage in RA patients. To date, six phase 3 trials have been conducted to evaluate the safety and efficacy of tofacitinib under the oral rheumatoid arthritis triaLs (ORAL) series. This review describes the pharmacology of the novel agent, tofacitinib, and details the safety and efficacy data of the ORAL trials.

Atacicept as an investigated therapy for rheumatoid arthritis

INTRODUCTION

Rheumatoid arthritis (RA) is a chronic, painful and debilitating autoimmune disease. Although the outcome for patients with RA has improved markedly in the past decades, adequate disease control cannot be achieved in a substantial proportion of patients. Since RA is a syndrome with different biological subsets, new drugs with a novel mechanism of action may represent a valuable addition to the current armamentarium.

AREAS COVERED

This review focuses on the pharmacodynamics and pharmacokinetics of atacicept . Furthermore, the article both summarises and comments on the drug's efficacy and safety profile in RA patients.

EXPERT OPINION

Atacicept is designed to neutralise B-lymphocyte stimulator (BLyS) and a proliferation-inducing ligand, two cytokines involving B-cell function and survival. Two recent Phase II studies have demonstrated that atacicept was not effective in RA patients with an inadequate response to methotrexate or TNF antagonists. However, atacicept displayed significant biological activity, including reduction of Ig and rheumatoid factor levels. Adverse events were slightly more frequent among patients treated with atacicept compared with placebo. In contrast to patients with systemic lupus erythematosus, RA patients receiving atacicept did not show an increased susceptibility to infections. In view of its important impact on immunoglobulin-secreting cells, this drug might be a rational therapy for hematological diseases.

Unmet needs in the treatment of autoimmunity: from aspirin to stem cells

As rheumatologic diseases became understood to be autoimmune in nature, the drugs used to treat this group of conditions has evolved from herbal or plant derived anti-inflammatory agents, such as salicylates, quinine and colchicine to the many recently approved biological response modifiers. These new drugs, especially the anti-tumor necrosis factor agents, have shown remarkable efficacy in autoimmune diseases, and there are new agents under investigation that will provide additional treatment options. In between, the world was introduced to cortisone and all of its derivatives, as chemical synthesis led to better, more efficacious drugs with lesser side effects. Disease modifying anti-rheumatic agents have actually been around since the first half of the 20th century, but only began to be used in the treatment of autoimmune diseases in the 1970s and 1980s. One advantage is that they have been invaluable in their ability to offer "steroid sparing" to decrease the adverse effects of steroids. Research over the past decade has resulted in a new class of drugs that influence cytokine regulatory pathways such as the Janus associated kinase inhibitors. The promise of personalized medicine now permeates current research into new pharmacological agents for the treatment of autoimmune disease. The new appreciation for the gene-environment interaction in the pathogenesis of most diseases especially those as heterogeneous as autoimmune diseases, has led to our focus on targeted therapies. Add to that the new knowledge of epigenetics and how changes in DNA and histone structure affect expression of genes that can play a role in immune signaling, and we now have a new exciting frontier for cutting edge drug development. The history of treatment of autoimmune diseases is really only a little over a century, but so much has changed, leading to increasing lifespans and improved quality of life of those who suffer from these ailments.

Clinical utility of the oral JAK inhibitor tofacitinib in the treatment of rheumatoid arthritis

Immune/inflammatory cells act in rheumatoid arthritis (RA)-affected patients by synthesizing several inflammatory mediators, including cytokines that initiate intracellular signaling. Recently, small molecule inhibitors of transduction and transcription signals that influence the intracellular pathways (such as the Janus kinase [JAK] family of tyrosine kinases) have been tested for RA treatment. Four members of the JAK family are known: JAK1, JAK2, JAK3, and TyK2. JAK1/JAK3 constitutively binds to the cytoplasmic portion of the cytokine receptor – the common gamma chain – that represents a common subunit of several cytokines involved in T-cell and natural killer cell development, as well as in B-cell activation. Tofacitinib is an oral JAK inhibitor that is now available and effective in RA treatment, as shown in multiple Phase II and Phase III clinical trials. However, long-term safety data and comparisons with other disease-modifying antirheumatic drugs and small molecule inhibitors are necessary to better determine the role of tofacitinib in RA.

The effectiveness of tofacitinib, a novel Janus kinase inhibitor, in the treatment of rheumatoid arthritis: a systematic review and meta-analysis

The aim of the present study was to conduct a meta-analysis of the effectiveness of tofacitinib, a novel oral Janus kinase inhibitor, recently approved for the treatment of active rheumatoid arthritis in patients who have failed previous treatment with methotrexate (MTX) or other disease-modifying antirheumatic drugs (DMARDs). A systematic literature search was conducted in PubMed, EMBASE, Cochrane Library, and other databases till 3 May 2013. All included studies were analyzed with the use of the Review Manager 5.1.0. software according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) Statement protocol. Nine randomized controlled trials (RCTs) comparing tofacitinib with placebo were identified. Two of them additionally provided the comparison with adalimumab. However, only eight RCTs met the inclusion criteria for the meta-analysis. The overall results of the meta-analysis showed that tofacitinib provided a statistically significant improvement according to the response criteria (ACR20/50/70) after 12 weeks of treatment when compared to placebo (p < 0.00001). Moreover, it was demonstrated that tofacitinib was significantly superior to adalimumab in achieving the ACR50 response criteria at week 12 (p = 0.003). For the safety analysis, there were no statistically significant differences between tofacitinib-, adalimumab-, and placebo-treated patients in respect to the risk of serious adverse events or treatment discontinuation due to adverse reactions (p > 0.05). The findings of this systematic review with meta-analysis indicate that tofacitinib monotherapy or with background methotrexate provides early statistically significant and clinically important improvement in rheumatoid arthritis symptoms and has an acceptable safety profile comparable to that of placebo. The results of the present meta-analysis show that the frequency of serious adverse events was not increased after tofacitinib treatment. In addition, tofacitinib might provide an effective treatment option compared to intravenous or subcutaneous biological DMARDs, as suggested by the result of the comparison made regarding tofacitinib vs. adalimumab ACR50 response rate.