Cytochrome P450 3A and P-glycoprotein drug-drug interactions with voclosporin

Clinical Pharmacokinetics and Pharmacodynamics of Voclosporin

Voclosporin is an approved option for the long-term treatment of lupus nephritis. We aimed to provide a narrative review of the pharmacokinetics and pharmacodynamics of voclosporin. In addition, we derived values for pharmacokinetic and pharmacodynamic parameters by graphical analysis of published diagrams. Compared with cyclosporin, low-dose voclosporin is associated with a lower nephrotoxicity risk and, compared to tacrolimus, with a lower diabetes risk. After repetitive dosing of 23.7 mg twice daily and at target trough concentrations of 10-20 ng/mL, the dominant or effect-indicative half-life is estimated at 7 hours. Compared with the pharmacodynamics of cyclosporin, the potency of voclosporin is stronger, with a lower concentration CE₅₀ of 50 ng/mL already producing the half-maximum immunosuppressive effect. The Hill coefficient can be predicted to be low at H = 1.3, indicating a concentration-dependent effect on the immune system. The corresponding effect bisection time of 10 hours allows for dosing every 12 hours. Accordingly, the trough concentration will be above the threshold concentration that produces 5% of the maximum effect of 5.2 ng/mL for immunosuppression but below both the predicted threshold of 30 ng/mL for nephrotoxicity and the predicted threshold of 40 ng/mL for new-onset diabetes. The pharmacokinetic and pharmacodynamic properties suggest the use of low-dose voclosporin combined with mycophenolate and low-dose glucocorticoids for immunosuppressive maintenance therapy.

Voclosporin: a novel calcineurin inhibitor for the treatment of lupus nephritis

INTRODUCTION

Lupus nephritis (LN) is a severe manifestation of systemic lupus erythematosus. Standard-of-care immunosuppressive therapies achieve poor complete renal response (CRR) rates, with considerable toxicity. This article reviews voclosporin, a novel oral calcineurin inhibitor (CNI) approved for treatment of adults with active LN by the US Food and Drug Administration (the FDA) in January 2021.

AREAS COVERED

: This review summarizes the chemical properties, pharmacokinetics, and pharmacodynamics of voclosporin, and its efficacy and safety in LN, based on literature review covering PubMed searches, manufacturers' websites and documents produced by the FDA.

EXPERT OPINION

: Voclosporin is a CNI with a consistent pharmacokinetic-pharmacodynamic relationship resulting from enhanced calcineurin binding and reduced drug and metabolite load. This profile permits therapeutic efficacy in LN at a dose associated with relatively low calcineurin inhibition, and therefore a potentially improved safety profile. Pivotal trials demonstrated a significant benefit of adding voclosporin to standard therapy, with rapid reduction in proteinuria, and a clinically meaningful and significantly higher CRR rate at 1 year. At approved doses for LN, potential advantages of voclosporin versus historical experience with CNIs include lack of need for therapeutic drug monitoring, benign metabolic, lipid and electrolyte profile, and no impact on mycophenolate mofetil levels.

2021 FDA TIDES (Peptides and Oligonucleotides) Harvest

From the medical, pharmaceutical, and social perspectives, 2021 has been a year dominated by the COVID-19 pandemic. However, despite this global health crisis, the pharmaceutical industry has continued its endeavors, and 2021 could be considered an excellent year in terms of the drugs accepted by the US Food and Drug Administration (FDA). Thus, during this year, the FDA has approved 50 novel drugs, of which 36 are new chemical entities and 14 biologics. It has also authorized 10 TIDES (8 peptides, 2 oligonucleotides), in addition to 2 antibody-drug conjugates (ADCs) whose structures contain peptides. Thus, TIDES have accounted for about 24% of the approvals in the various drug categories. Importantly, this percentage has surpassed the figure in 2020 (10%), thus reflecting the remarkable success of TIDES. In this review, the approved TIDE-based drugs are analyzed on the basis of their chemical structure, medical target, mode of action, administration route, and adverse effects.

Voclosporin: a novel calcineurin inhibitor for the management of lupus nephritis

INTRODUCTION

Kidney survival rates in lupus nephritis (LN) remain suboptimal, with 10-20% of patients progressing to end-stage kidney disease by 10-20 years. Recently, the landscape of LN management has changed with the advent of new molecules that have demonstrated safety and efficacy in clinical trials.

AREAS COVERED

In this review, we approach the current state of LN management, the unmet therapeutic needs, and deep dive into voclosporin, a novel calcineurin inhibitor (CNI) that has demonstrated improved efficacy when added to a mycophenolate mofetil (MMF) and glucocorticoid regimen, without an increase in adverse events. We focus on the characteristics of this new CNI and the studies that led to its approval by the US FDA.

EXPERT OPINION

Voclosporin adds to therapeutic options for LN. This drug offers potential advantages over other CNIs. The addition of voclosporin to a standard-of-care regimen of MMF/glucocorticoids demonstrated higher and faster response rates. As other regimens, a combination of CNI, MMF, and glucocorticoids must be individualized and is not appropriate for all patients. Some questions remain to be answered for this regimen, such as the length of treatment, the tapering schedule, and its long-term safety and efficacy for preserving kidney function.

Voclosporin: First Approval

Voclosporin (Lupkynis^™) is an oral calcineurin inhibitor immunosuppressant that is being developed by Aurinia Pharmaceuticals. In January 2021, based on positive results from the pivotal phases II and III trials, oral voclosporin received its first approval in the USA for use in combination with a background immunosuppressive therapy regimen for adults with active lupus nephritis. Voclosporin is also being explored for the novel coronavirus disease 2019 (COVID-19) in kidney transplant recipients. This article summarizes the milestones in the development of voclosporin leading to this first approval for lupus nephritis.

Fentanyl Enhances Hepatotoxicity of Paclitaxel via Inhibition of CYP3A4 and ABCB1 Transport Activity in Mice

Fentanyl, a potent opioid analgesic that is used to treat cancer pain, is commonly administered with paclitaxel in advanced tumors. However, the effect of fentanyl on the hepatotoxicity of paclitaxel and its potential mechanism of action is not well studied. The purpose of this study was to investigate the effect of fentanyl on the hepatotoxicity of paclitaxel and its potential mechanisms of action. Pharmacokinetic parameters of paclitaxel were tested using reversed phase high-performance liquid chromatography (RP-HPLC). Aspartate transaminase (AST), alanine aminotransferase (ALT), and mouse liver histopathology were examined. Moreover, the cytotoxicity of anti-carcinogens was examined using 1-(4, 5-dimethylthiazol-2-yl)-3,5-diphenylformazan (MTT), and the intracellular accumulation of doxorubicin and rhodamine 123 was detected by flow cytometry. Furthermore, the expression of ABCB1 and the activity of ABCB1 ATPase and CYP3A4 were also examined. In this study, the co-administration of fentanyl and paclitaxel prolonged the half-life (t_1/2) of paclitaxel from 1.455 hours to 2.344 hours and decreased the clearance (CL) from 10.997 ml/h to 7.014 ml/h in mice. Fentanyl significantly increased the levels of ALT in mice to 88.2 U/L, which is more than 2-fold higher than the level detected in the control group, and it increased the histological damage in mouse livers. Furthermore, fentanyl enhanced the cytotoxicity of anti-carcinogens that are ABCB1 substrates and increased the accumulation of doxorubicin and rhodamine 123. Additionally, fentanyl stimulated ABCB1 ATPase activity and inhibited CYP3A4 activity in the liver microsomes of mice. Our study indicates that the obvious hepatotoxicity during this co-administration was due to the inhibition of CYP3A4 activity and ABCB1 transport activity. These findings suggested that the accumulation-induced hepatotoxicity of paclitaxel when it is combined with fentanyl should be avoided.