Slower Elimination of Tofacitinib in Acute Renal Failure Rat Models: Contribution of Hepatic Metabolism and Renal Excretion

Rational approach to the prescription of anti-rheumatic drugs in rheumatoid arthritis: a product leaflet-based strategy in Italy

The treatment of patients with rheumatoid arthritis (RA) has dramatically changed in the past 30 years. Currently, numerous conventional, biologic, and targeted synthetic DMARDs have been licensed and used following recommendations provided by international and national scientific societies. However, the availability of biosimilars and the increasing necessity of savings impacted on the local/national prescription of these drugs. The information provided by data sheet of every single drug is a decisive factor on the choice of a certain treatment merged with the patient's profile. Thus, our purpose was to construct a rational algorithm for the treatment strategy in RA according to costs and the product leaflet of the biologic and targeted-synthetic DMARDs currently licensed in Italy. We used the most recent available recommendations and then we performed a review of the literature considering all the factors that are known to influence drug safety/effectiveness. All these factors were considered in the context of the data sheets of currently available originators and biosimilars.

The Impact of Baohuoside I on the Metabolism of Tofacitinib in Rats

Purpose

To study the potential drug-drug interactions between tofacitinib and baohuoside I and to provide the scientific basis for rational use of them in clinical practice.

Methods

A total of eighteen Sprague-Dawley rats were randomly divided into three groups: control group, single-dose group (receiving a single dose of 20 mg/kg of baohuoside I), and multi-dose group (receiving multiple doses of baohuoside I for 7 days). On the seventh day, each rat was orally administered with 10 mg/kg of tofacitinib 30 minutes after giving baohuoside I or vehicle. Blood samples were collected and determined using UPLC-MS/MS. In vitro effects of baohuoside I on tofacitinib was investigated in rat liver microsomes (RLMs), as well as the underlying mechanism of inhibition. The semi-inhibitory concentration value (IC50) of baohuoside I was subsequently determined and its inhibitory mechanism against tofacitinib was analyzed. Furthermore, the interactions between baohuoside I, tofacitinib and CYP3A4 were explored using Pymol molecular docking simulation.

Results

The administration of baohuoside I orally has been observed to enhance the area under the concentration-time curve (AUC) of tofacitinib and decrease the clearance (CL). The observed disparity between the single-dose and multi-dose groups was statistically significant. Furthermore, our findings suggest that the impact of baohuoside I on tofacitinib metabolism may be a mixture of non-competitive and competitive inhibition. Baohuoside I exhibit an interaction with arginine (ARG) at position 106 of the CYP3A4 enzyme through hydrogen bonding, positioning itself closer to the site of action compared to tofacitinib.

Conclusion

Our study has demonstrated the presence of drug-drug interactions between baohuoside I and tofacitinib, which may arise upon pre-administration of tofacitinib. Altogether, our data indicated that an interaction existed between tofacitinib and baohuoside I and additional cares might be taken when they were co-administrated in clinic.

Safety and Effectiveness of Tofacitinib in Treating Polyarticular Course Juvenile Idiopathic Arthritis

Polyarticular course juvenile idiopathic arthritis (pcJIA) is a form of arthritis that affects at least five joints at a time and presents before the age of 16. Its most common symptoms are pain, swelling, redness, and a limited range of motion, making it incredibly difficult for patients diagnosed to function in daily life. Historically, the leading treatment options have consisted of non-steroidal anti-inflammatory drugs (NSAIDs) and disease-modifying antirheumatic drugs (DMARDs) such as methotrexate. However, these drugs have serious toxic side effects associated with long-term use in addition to being ineffective in refractory cases. Recently, small molecule biologics have emerged as an alternate treatment to pcJIA. Tofacitinib is a small molecule JAK inhibitor that blocks the JAK/STAT cascade and decreases the transcription of genes responsible for immune function. We conducted a risk-benefit analysis to determine the viability of tofacitinib as a treatment for pcJIA. In our review, we found the side effect profile of tofacitinib to be relatively mild, with many of the serious adverse side effects occurring in those immunocompromised and those with impaired renal and hepatic metabolism. Overall, we have determined that tofacitinib has the potential to be effective in reducing flare-ups and lowering erythrocyte sedimentation rate (ESR) in immunocompetent patients with pcJIA. Additionally, our review has found that tofacitinib has the potential to be effective in patients who are refractory to traditional treatment. However, large-scale clinical trials are needed to determine if this effect holds true in younger pediatric populations, as limited data surrounds this demographic.

Effects of Hyperlipidemia on the Pharmacokinetics of Tofacitinib, a JAK 1/3 Inhibitor, in Rats

Tofacitinib, an inhibitor of Janus kinases (JAKs) 1 and 3, has been shown to be effective in the treatment of rheumatoid arthritis. The incidence of hyperlipidemia has been found to be higher in patients with rheumatoid arthritis. The present study therefore investigated the pharmacokinetics of tofacitinib after its intravenous (10 mg/kg) or oral (20 mg/kg) administration in poloxamer-407-induced hyperlipidemic (PHL) rats. The area under the plasma concentration-time curve from zero to infinity (AUC0-∞) after intravenous administration of tofacitinib was 73.5% higher in PHL than in control rats, owing to slower time-averaged nonrenal clearance (CLNR) in the former. Evaluation of in vitro metabolism showed that the intrinsic clearance (CLint) of tofacitinib was 38.6% lower in PHL than in control rats, owing to the decreased protein expression of hepatic cytochrome P450 (CYP) 3A1/2 and CYP2C11 in PHL rats. Similar results were observed in PHL rats after oral administration of tofacitinib. These results were likely due to the decreased CLNR, CLint, and P-glycoprotein (P-gp) expression in the intestines of PHL compared to control rats. Overall, these findings indicated that hyperlipidemia slowed the metabolism of tofacitinib, increasing its plasma concentrations, and that this reduced metabolism was due to alterations in expression of the proteins CYP3A1/2, CYP2C11, and P-gp in the liver and/or intestines of PHL rats.

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).

Effects of Dextran Sulfate Sodium-Induced Ulcerative Colitis on the Disposition of Tofacitinib in Rats

Tofacitinib, a Janus kinase 1 and 3 inhibitor, is mainly metabolized by CYP3A1/2 and CYP2C11 in the liver. The drug has been approved for the chronic treatment of severe ulcerative colitis, a chronic inflammatory bowel disease. This study investigated the pharmacokinetics of tofacitinib in rats with dextran sulfate sodium (DSS)-induced ulcerative colitis. After 1-min of intravenous infusion of tofacitinib (10 mg/kg), the area under the plasma concentration-time curves from time zero to time infinity (AUC) of tofacitinib significantly increased by 92.3%. The time-averaged total body clearance decreased significantly by 47.7% in DSS rats compared with control rats. After the oral administration of tofacitinib (20 mg/kg), the AUC increased by 85.5% in DSS rats. These results could be due to decreased intrinsic clearance of the drug caused by the reduction of CYP3A1/2 and CYP2C11 in the liver and intestine of DSS rats. In conclusion, ulcerative colitis inhibited CYP3A1/2 and CYP2C11 in the liver and intestines of DSS rats and slowed the metabolism of tofacitinib, resulting in increased plasma concentrations of tofacitinib in DSS rats.

Pharmacokinetic Drug Interaction between Tofacitinib and Voriconazole in Rats

Fungal infections are prevalent in patients with immune diseases. Voriconazole, a triazole antifungal drug, inhibits the cytochromes CYP3A4 and CYP2C, and tofacitinib, a Janus kinase inhibitor for the treatment of rheumatoid arthritis, is metabolized by CYP3A4 and CYP2C19 in humans. Here, we investigated their interaction during simultaneous administration of both drugs to rats, either intravenously or orally. The area under the plasma concentration–time curve from time zero to time infinity (AUC) of tofacitinib was significantly greater, by 166% and 171%, respectively, and the time-averaged non-renal clearance (CL_NR) of tofacitinib was significantly slower (59.5%) than that for tofacitinib alone. An in vitro metabolism study showed non-competitive inhibition of tofacitinib metabolism in the liver and intestine by voriconazole. The concentration/apparent inhibition constant (K_i) ratios of voriconazole were greater than two, indicating that the inhibition of tofacitinib metabolism could be due to the inhibition of the CYP3A1/2 and CYP2C11 enzymes by voriconazole. The pharmacokinetics of voriconazole were not affected by the co-administration of tofacitinib. In conclusion, the significantly greater AUC and slower CL_NR of tofacitinib after intravenous and oral administration of both drugs were attributable to the non-competitive inhibition of tofacitinib metabolism via CYP3A1/2 and CYP2C11 by voriconazole in rats.