Bioequivalence study between two formulations of ciclosporin A (Cyclavance® oral solution and Atopica® soft capsules) following a single oral administration to dogs

Preparation of altrenogest soft capsules and their bioequivalence in gilts

Introduction

Altrenogest (ALT) is widely used to regulate the estrous cycle of sows and mares; however, currently used oral solutions of ALT are deficient in terms of dose accuracy and stability during use. To resolve these problems, we aimed to prepare softgel capsules of ALT with a unit dose equal to the clinically administered dose.

Method

The shell of the softgel capsule was mainly composed of gelatin and glycerol, with titanium dioxide and red iron oxide as masking agents. Using the shake flask method, the contents were screened for ethyl acetate as a lipophilic solubilizing carrier based on soya bean oil. The contents were automatically filled and compressed into softgel capsules by a softgel capsule machine. The quality of the prepared softgel capsules was evaluated through a drug content test, an in vitro release test, and stability studies. Furthermore, bioequivalence studies were conducted with atrenogest oral solution.

Results

The content is an ALT concentration of 2% oil solution and the specification of the softgel is 20 mg/capsule. In in vitro dissolution experiments, the softgel capsules were rapidly disintegrated and released in three different pH buffers, with a cumulative release rate of nearly 100% at 1 h. The softgel capsules were stable at high temperature and under strong light for 10 days, and the concentration of ALT was >99% in the 6-month accelerated and long-term tests. In the bioequivalence study, Tmax of the softgel capsules was 2.20 ± 0.77 h, t 1/2 was 6.36 ± 1.74 h, and C max was 64.65 ± 20.69 ng/ml. The main pharmacokinetic parameters T max, C max, AUC 0-t, and AUC 0-∞, did not differ significantly between the softgel capsules and the commercially available ALT oral solution (P > 0.05), and bioequivalence was demonstrated within the 90% confidence interval.

Conclusion

The prepared softgel capsules have the advantages of higher content, ease of use with accurate dosing, good stability, and equivalence to ALT oral solution, implying that our softgels are ready for clinical use.

Pharmacology of drugs used in autoimmune dermatopathies in cats and dogs: A narrative review

Immunosuppressive drugs are the mainstay of treatment for many feline and canine autoimmune skin diseases, either as monotherapy or in combination with other drugs. Treatment with these drugs is often lifelong and may have long-term consequences on the affected animal's overall quality-of-life. Clinicians need to understand the pharmacology of immunosuppressants in planning and executing the treatment regimen for the best possible clinical outcome, as well as reducing the risk of adverse effects. This review paper will focus on the mechanism of action, pharmacokinetics and pharmacodynamics, clinical uses and adverse effects of immunosuppressive drugs used to treat autoimmune dermatoses in cats and dogs. These include glucocorticoids, ciclosporin A, azathioprine, chlorambucil, mycophenolate mofetil, oclacitinib and Bruton's tyrosine kinase inhibitors.

Comparison of whole blood concentrations of oral human generic modified ciclosporin capsules with microemulsified ciclosporin capsules approved for canine atopic dermatitis following a single oral administration to healthy dogs

BACKGROUND

There have been no comparative bioavailability studies between the microemulsified ciclosporin formulation, approved for the treatment of canine atopic dermatitis (cAD), and the generic modified formulation of ciclosporin for humans.

OBJECTIVES

To compare whole blood ciclosporin concentrations of oral generic modified ciclosporin (Treatment A; Teva Pharmaceuticals) and ciclosporin brand Atopica (Treatment B; Elanco Animal Health) in healthy dogs at 1 and 1.5 h following a single oral administration.

METHODS

Whole blood concentrations were evaluated at 1 and 1.5 h post-oral administration of treatments A and B in a randomised, blinded, cross-over study with an 8-day wash-out, after a single administration at 4.4-5.3 mg/kg/day in eight healthy, male-castrated research beagle dogs. Ciclosporin blood concentrations were measured through the Auburn University Clinical Pharmacology Laboratory.

RESULTS

Ciclosporin blood concentrations were below the detection limit before the start of treatment for both groups. Blood ciclosporin concentrations for Treatment A (median 1192 ng/ml) were significantly higher at 1 h post-oral administration than those for Treatment B (median 499 ng/ml; p = 0.001). However, no significant differences (p = 0.75) in ciclosporin values were observed at 1.5 h post-administration between treatments A (median 945 ng/ml) and B (median 809 ng/ml).

CONCLUSIONS AND CLINICAL RELEVANCE

Generic modified ciclosporin achieved higher blood concentrations at 1 h post-administration than Atopica after a single oral administration in healthy dogs; no difference was noted at 1.5 h. Further clinical studies using generic modified ciclosporin in client-owned dogs affected with cAD are advocated to confirm its therapeutic efficacy.

Pharmacokinetics and bioequivalence of two cyclosporine oral solution formulations in cats

The pharmacokinetic profiles and bioequivalence of two cyclosporine oral solutions were investigated in cats. Twenty-four cats were randomly allocated to two equally sized treatment groups in a randomized four-cycle, and dual-sequence cross-over design. Test and reference articles were orally administered in a single dose of 7 mg/kg Bodyweight. Serial blood samples were collected, and blood cyclosporine concentration was determined by ultra-performance liquid chromatography-mass spectrometry (UPLC-MS/MS). No significant differences were present in the major pharmacokinetic parameters (Cmax, AUC0−last,) between the two formulations. The blood profiles of cyclosporine following the administration of both formulations were similar. The findings of the study suggested that the two articles were bioequivalent for cyclosporine oral solution.

Clinical Guidelines for the Use of Antipruritic Drugs in the Control of the Most Frequent Pruritic Skin Diseases in Dogs

Pruritus is a common clinical sign in many skin disorders and is currently the main complaint in canine dermatology. Pruritic skin diseases can affect the quality of life of dogs and their owners. Several families of antipruritic drugs are available to help control pruritus in dogs. The aim of this review is to help practitioners select the most appropriate symptomatic treatment in the most frequent situations of dermatological pruritus in dogs. The molecules reviewed here are systemic and topical glucocorticoids, antihistamines, ciclosporin, oclacitinib and lokivetmab. A level of evidence (1, 2 or 3) has been established according to a detailed algorithm for each individual study in the literature published between 1990 and March 2021. The guidelines result from evidence grading using the strength of recommendation taxonomy (SoRT) and clinical recommendations using a thorough methodology.

Comparative study to evaluate the voluntary acceptance of two liquid oral formulations of ciclosporin in dogs

Background

The purpose of this study was to determine and compare the voluntary acceptance of two oral liquid formulations of ciclosporin, investigational Atopica® oral solution (Elanco Animal Health) and Cyclavance® Oral Solution (Virbac), when given orally via syringe or offered freely after mixing with food to dogs.

Twenty-five adult mixed breed dogs were selected for this two-phase study. In Phase 1, 12 (Group I) and 13 (Group II) dogs received Atopica® oral solution and Cyclavance® Oral Solution, respectively, daily for 7 days via an oral syringe. After a 3-day washout period, the dosing was switched for a further 7 days. For Phase 2, dosing was by acceptance from freely offered test article mixed in a small amount of food, approximately 6 h after the routine morning feeding. During the first part of this phase, normal daily ration of food offered in the morning was continuously left in the cage. Group I was offered Atopica® oral solution and Group II was offered Cyclavance® Oral Solution mixed with ~ 25 g of food for 3 days. After another 2-day washout period, the test articles were switched for another 3 days but the animals received food for only 1 h in the morning. Five hours after the food was removed, the test articles with food were offered in the same manner as in the first part of Phase 2. Animals were also monitored for adverse events (AEs).

Results

During Phase I, voluntary acceptance rates of 100 and 98.9% were noted for Atopica® oral solution and Cyclavance® Oral Solution, respectively. The corresponding immediate prehension rates during Phase 2 (Period 1) were 61.1 and 56.4%, respectively. During Phase 2 (Period 2), the immediate prehension rates were 69.2, 69.4 and 92.0% for Atopica® oral solution, Cyclavance® Oral Solution and the positive control (DYNE®; High Calorie Liquid Dietary Supplement), respectively. Two adverse events of diarrhea and vomiting, with a probable relationship to the test articles, were reported.

Conclusion

There was no significant difference in acceptance of the two oral ciclosporin solutions, the investigational Atopica® oral solution (Elanco) and Cyclavance® (Virbac) for dogs.

Electronic supplementary material

The online version of this article (10.1186/s13620-018-0138-9) contains supplementary material, which is available to authorized users.

The Diabetic Dog as a Translational Model for Human Islet Transplantation

The dog model has served as the primary method for early development of many diabetes therapies, including pancreatic islet transplantation techniques and immunosuppressive protocols. Recent trends towards the use of monoclonal antibody therapies for immunosuppression in human islet transplantation have led to the increasing use of primate models with induced diabetes. In addition to induced-disease models in large animals, scientists in many fields are considering the use of naturally-occurring disease models in client-owned pets. This article will review the applicability of naturally-occurring diabetes in dogs as a translational model for developing islet transplantation in the human diabetic patient.

A comparison of liquid chromatography-tandem mass spectrometry (LC-MS/MS) and enzyme-multiplied immunoassay technique (EMIT) for the determination of the cyclosporin A concentration in whole blood from Chinese patients

Cyclosporin A (CyA) is an immunosuppressive agent widely used in clinical therapy. In the therapeutic process, the blood concentration of CyA should be monitored to avoid or prevent rejection and toxicity. The objectives of this study were to compare the correlation of liquid chromatography-tandem mass spectrometry (LC-MS/MS) and enzyme-multiplied immunoassay technique (EMIT) for the determination of the CyA concentration in human blood and to provide evidence for the rational usage of EMIT in clinical practice. Blood samples collected from 132 patients undergoing a liver or kidney transplant or patients with aplastic anemia at Qilu Hospital of Shandong University were tested using the two methods. The calibration curve was linear from 25-500 ng·mL^-1 for LC-MS/MS and from 50-450 ng·mL^-1 for EMIT. The inter- and intra-day RSDs were less than 15%. The CyA blood concentration according to EMIT was 3.5 ng·mL^-1 more than that according to LC-MS/MS. The 95% confidence interval was -10.0~16.9 ng·mL^-1. The CyA blood concentration according to the two methods did not differ significantly (p > 0.05). LC-MS/MS and EMIT were suitable methods for determining the CyA blood concentration. The two methods were closely correlated (r² = 0.969), but the CyA blood concentration according to EMIT was slightly higher than that according to LC-MS/MS. The clinical significance of this finding needs to be further evaluated.

Cyclosporine A disposition, hepatic and renal tolerance in Wistar rat

Cyclosporine A, a potent calcineurin inhibitor, has been widely used in organ transplantation and in the treatment of autoimmune diseases. It has, however, been shown to induce serious renal and hepatic side effects. The drug is also used in preclinical studies, but with little published information on the optimal dose and route of administration in rodents. Objectives of this study were to identify efficient and safe doses of cyclosporine A in rodent and to assess its effects on hepatic and renal functions. For this purpose, we tested the effects of different doses and administration routes of cyclosporine A (5, 2.5 and 1 mg/kg) administered during 28 days intraperitoneally, or by gastric feeding on Wistar rats. Our data indicate that rats injected intraperitoneally with 5 mg/kg/2d (every two days) exhibited trough cyclosporine A levels within known therapeutic range in human, but were subject to blood cyclosporine A accumulation, whereas the 5 mg/kg/d gavage resulted in only a small cyclosporine A accumulation over time. In both cases this accumulation was not deleterious to renal and hepatic functions, as shown by transaminase, urea, creatinine and bilirubin measurements.