Safety, tolerability, and pharmacokinetics of 6-month daily dosing of an oral formulation of cyclosporine (ATOPICA for cats®) in cats

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.

Pharmacokinetics of a single orally administered therapeutic dosage of cyclosporine A in healthy cats

This study aimed to determine a pharmacokinetic profile for a single dosage of cyclosporine A (CsA) clinically used for immunosuppression in cats. Blood-CsA-concentrations were measured before and 1, 2, 4, 6, 8, 12 and 24 h after oral administration of 7 mg/kg body weight (BW) CsA (Atopica® oral solution) to 8 healthy adult cats using high-performance liquid chromatography coupled to mass spectrometry. Pharmacokinetic parameters were calculated using WinNonLin software based on a 1-compartment-model. The median maximum plasma-concentration of 1466 ng/ml (530-2235 ng/ml; minimum-maximum) was reached after 2.0 h (1.0-4.7 h). The area under the curve was 12,568 h x ng/ml (5732-20,820 h x ng/ml) and the apparent total clearance of the drug from plasma was 557 ml/h/kg (336-1221 ml/h/kg). Half-life of absorption into the central compartment was 0.6 h (0.4-2.6 h), half-life of elimination from the central compartment was 4.6 h (1.4-7.5 h).

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.

Cyclosporine Treatment in Cats with Presumed Chronic Pancreatitis-A Retrospective Study

Simple Summary

Chronic pancreatitis (CP) is a common disease in middle-aged to older cats. Cyclosporine, an immunosuppressive drug, has been suggested as an alternative treatment when other drugs that suppress inflammation are ineffective or unsuitable. However, no published studies have investigated its efficacy in cats with CP. The aim of this retrospective study was to evaluate the efficacy of cyclosporine as a treatment for pancreatitis in cats with presumed CP. All cats had a history and clinical signs suggestive of CP and blood samples showed abnormally high concentrations of feline pancreas-specific lipase (Spec fPL) on at least two occasions. This is common in CP. All cats were treated with cyclosporine for at least three weeks. Nineteen cats, aged 6.9–17.5 years, were included. Daily treatment with cyclosporine resulted in an improvement of serum Spec fPL concentrations which indicates that the pancreatic inflammation likely had improved. The study has several limitations, including different treatment durations and doses, lack of biopsies to confirm CP and the treatment effect was not compared with an untreated control group. Despite the limitations, our results suggest that cyclosporine treatment decreases serum Spec fPL concentrations and may be effective in the management of feline chronic pancreatitis.

Abstract

Chronic pancreatitis (CP) is a common disease in middle-aged to older cats. Cyclosporine has been suggested as an alternative treatment when other immunosuppressive treatments are insufficient or contraindicated. However, no published studies have investigated its efficacy on feline CP. The aim of this retrospective study was to evaluate the efficacy of cyclosporine on supranormal serum feline pancreas-specific lipase (Spec fPL) concentrations in cats with presumed CP. Inclusion criteria were history and clinical signs suggestive of CP, serum Spec fPL concentrations above 5.3 μg/L (reference range 0–3.5 μg/L, equivocal range 3.6–5.3 μg/L) on at least two occasions and treatment with cyclosporine for at least three weeks. Serum Spec fPL was analyzed at Idexx Laboratories, Kornwestheim, Germany. Nineteen cats, aged 6.9–17.5 years (median 11.6), were included. No pancreatic biopsies were available. Median (range) serum Spec fPL concentration was 14.2 μg/L (6.1–43.3) at baseline and 6.7 μg/L (0.9–23.6) at follow-up. Cyclosporine treatment (5.0–7.9 mg/kg orally SID) was associated with a significant reduction in serum Spec fPL concentrations (p < 0.001) at follow-up after 23–206 days (median 35). Body weight decreased significantly between inclusion and follow-up (p = 0.013). Significant improvement of clinical signs could not be measured (p = 0.781). This study has several limitations, including unstandardized treatment length and dose, no control group and lack of pancreatic biopsies. Despite the limitations, our results suggest that cyclosporine treatment reduces supranormal serum Spec fPL concentrations in cats with presumed CP.

Treatment of the feline atopic syndrome - a systematic review

BACKGROUND

Feline allergic skin disease and asthma occur regularly in small animal practice.

OBJECTIVES

To provide evidence-based recommendations for small animal practitioners on the treatment of feline atopic syndrome (FAS).

METHODS AND MATERIALS

The authors reviewed the literature available before February 2020, prepared a detailed evidence-based literature review and made recommendations based on the evaluated evidence.

RESULTS

Sixty-six papers and abstracts were identified describing treatment interventions for FAS and evaluated to establish treatment recommendations. For many treatment options, the papers were retrospective, open studies or case reports.

CONCLUSION AND CLINICAL RELEVANCE

In this review, there was good evidence for the efficacy of systemic glucocorticoids and ciclosporin, and limited evidence for the efficacy of topical glucocorticoids, oclacitinib and allergen-specific immunotherapy in feline atopic skin syndrome. Evidence pointed to low-to-moderate efficacy for antihistamines, fatty acids and palmitoyl ethanolamide. In feline asthma, there was good evidence for the efficacy of oral and inhaled glucocorticoids, and limited evidence of moderate efficacy for allergen-specific immunotherapy. Evidence supported low-to-moderate efficacy of mesenchymal stem cells, inhaled lidocaine and oclacitinib as treatments for feline asthma. For almost all therapeutic options (with the exception of glucocorticoids and ciclosporin), more randomised controlled trials are needed.

Feline non-regenerative anemia: Diagnostic and treatment recommendations

PRACTICAL RELEVANCE

Non-regenerative anemia, or anemia with reticulocytopenia, is a daily diagnosis in feline practice.

CLINICAL CHALLENGES

The disease processes underlying non-regenerative anemia are many and diverse. A major diagnostic evaluation may be required to correctly diagnose and treat the underlying cause.

AUDIENCE

All veterinarians caring for cats will face the diagnostic and therapeutic challenge of non-regenerative anemia. Readers will benefit from the review of diagnostic testing and therapeutic options for non-regenerative anemia.

EVIDENCE BASE

This review summarizes the currently available literature informing diagnostic and treatment recommendations related to non-regenerative anemia. The evidence available to support the recommendations in this review is graded as low and includes predominantly expert opinion, case reports and cases series, on which the authors' interpretation/consensus is based.

Ciclosporin and the cat: Current understanding and review of clinical use

Practical relevance: Ciclosporin (CsA) is a systemic immuno-modulatory drug widely used to treat immune-mediated diseases in humans and veterinary species. CsA was registered for use in cats in the USA and Europe in 2011, and is indicated for the treatment of chronic allergic dermatitis at a recommended daily dose of 7 mg/kg PO.

AUDIENCE

This review will be of interest to all veterinarians working with cats, given the wide range of potential applications of CsA and its safety profile. Although the drug is currently only licensed to treat chronic allergic dermatitis in cats, a small number of reports describe its use in non-dermatological conditions. Evidence base: This article reviews the mechanism of action, pharmacokinetics, drug interactions, adverse effects and clinical use of CsA, both for the licensed indication and for off-label use in the feline patient. Information presented has been summarised from the existing literature on CsA, with specific interest in studies carried out in cats. For its licensed indication, chronic allergic dermatitis, evidence provided includes randomised, placebo or prednisolone-controlled studies (EBM grade I) and prospective or retrospective open trials.

Felis Catus Gammaherpesvirus 1 DNAemia in Whole Blood from Therapeutically Immunosuppressed or Retrovirus-Infected Cats

Gammaherpesviruses are major co-pathogens of human immunodeficiency virus (HIV) infection, making the interactions between feline immunodeficiency virus (FIV) and Felis catus gammaherpesvirus 1 (FcaGHV1) pertinent to both human and veterinary medical research. FIV-infected cats are at increased risk of FcaGHV1 DNAemia and consistently harbor higher FcaGHV1 loads than FIV-uninfected cats. Whether immune deficiencies unrelated to FIV are associated with similar risks is unknown. Using whole blood FcaGHV1 qPCR, we found no difference in the frequency of DNAemia or DNA load in therapeutically immunosuppressed (P1, n = 18) or feline leukemia virus (FeLV)-infected (P2, n = 57) patients compared with age- and sex-matched controls (C1, n = 58; C2, n = 57). In contrast, FIV/FeLV-co-infected cats (P3, n = 5) were at increased risk of FcaGHV1 DNAemia compared to retrovirus uninfected controls (C3, n = 39; p = 0.0068), and had a higher median FcaGHV1 DNA load, although the latter was not significant. FIV/FeLV-co-infected cats (P3) had a similar frequency of FcaGHV1 DNAemia reported compared to FIV-infected controls (C4). In conclusion, we found no evidence that cats with therapeutic immunosuppression or FeLV infection were at greater risk of FcaGHV1 DNAemia or had higher FcaGHV1 DNA load in whole blood. The risk of DNAemia in FIV/FeLV-co-infected cats was similar to that documented previously in cats infected with FIV alone.

Confirmatory field study for the evaluation of ciclosporin at a target dose of 7.0 mg/kg (3.2 mg/lb) in the control of feline hypersensitivity dermatitis

Objectives This study was designed to confirm the efficacy and tolerability of a daily dose of 7.0 mg/kg (3.2 mg/lb) ciclosporin (CsA) in the treatment of feline hypersensitivity dermatitis (HD), as this includes some of the most frequently suspected skin diseases in cats and recent publications have reported the successful use of CsA in the treatment of feline HD. Methods In total, 217 cats with feline HD were treated daily for 42 days with a target dose of 7 mg/kg CsA (n = 144) or a placebo control (n = 73) administered either in the food or directly in the mouth following feeding. Clinical and dermatological evaluations were conducted on days 0, 21 and 42, or study exit. Safety was evaluated through physical examinations, clinical pathology and the monitoring of adverse events (AEs). Results Administration of CsA at 7.0 mg/kg produced a significant improvement in the total lesion score ( P <0.0001). The average reduction from visit 1 to visit 3 was 65.1% in the CsA group (9.2% for the placebo). In addition, owners assessed 78.3% of the cases in the CsA group as a success. Statistically significant recoveries were also seen in extent of lesions, investigator assessment of overall improvement, and mean improvement in both the investigators' and owners' assessment of pruritus. Mild gastrointestinal disorders were the most common AEs but did not require cessation of therapy. Conclusions and relevance Results confirm that 7.0 mg/kg CsA dosed daily in food or orally for up to 6 weeks is effective and well tolerated by cats with feline HD.

Clinical efficacy and safety following dose tapering of ciclosporin in cats with hypersensitivity dermatitis

Objectives This study was designed to evaluate the efficacy and safety of reducing ciclosporin (CsA) dosing frequency from daily to every other day (EOD) or twice a week (TW) according to clinical response in cats with hypersensitivity dermatitis (HD) and treated with CsA. Methods One hundred and ninety-one cats with HD were given 7 mg/kg CsA daily for at least 4 weeks. Depending on clinical response, the dosing frequency was tapered from daily to EOD over the next 4 weeks and further to TW for an additional 4 weeks. Safety was evaluated through physical examinations, clinical pathology and the monitoring of adverse events (AEs). Results The majority of cats were able to have their dose of CsA tapered to either EOD (15.5%) or TW (62.9%) according to the clinical response. Observed AEs were most frequently mild and self-limiting vomiting and diarrhea. A higher percentage of AEs occurred with daily administration (73%) compared with other dosing regimens (27%). Conclusions and relevance Following 4 weeks of daily dosing at 7 mg/kg, CsA may be tapered to EOD or TW while maintaining the desired therapeutic response in cats with HD. Additionally, CsA appears to be well tolerated with fewer AEs at EOD or TW dosing. Establishing the lowest effective dosing frequency of CsA improves the drug's safety profile.

Update in feline therapeutics: clinical use of 10 emerging therapies

PRACTICAL RELEVANCE

The field of veterinary medicine is constantly evolving. New medications are being introduced into clinical practice, and novel uses for established medications are frequently being discovered as new information comes to light.

CLINICAL CHALLENGES

Therapeutic options for our feline patients can be restricted based on inadequate clinical evidence, adverse effects and patient compliance concerns. Additionally, with the reduced availability of commonly used medications in some regions, clinicians are forced to utilize alternatives with which they may have limited experience.

AUDIENCE

This review article is directed towards primary care veterinarians working with feline patients. The selection of medications discussed is based on many of the clinical challenges commonly encountered in practice.

EVIDENCE BASE

The evidence for use of some of these medications is limited due to their novelty. Known mechanisms of action, pharmacokinetic and pharmacodynamics data, adverse effects and clinical uses are reviewed where possible, with clinical recommendations made based on the evidence of data available.

Effect of high-dose ciclosporin on the immune response to primary and booster vaccination in immunocompetent cats

Ciclosporin (Atopica oral solution for cats 100 mg/ml; Novartis Animal Health) was recently approved for use in cats with feline hypersensitivity dermatitis. The immunosuppressant effect of ciclosporin on the ability of cats to mount an immune response following vaccination was determined. Thirty-two healthy, immunocompetent adult cats (16 cats/group) were treated with either ciclosporin for 56 days at a dose of 24 mg/kg once daily or sham dosed. Prior to treatment, cats had an adequate antibody response to primary vaccination against feline calicivirus (FCV), feline herpesvirus-1 (FHV-1), feline panleukopenia virus (FPV), feline leukemia virus (FeLV) and rabies. Booster vaccination or novel vaccination with feline immunodeficiency virus (FIV) was administered 28 days after initiation of treatment with ciclosporin. There were no differences between the ciclosporin-treated and control cats for FCV and FPV antibody titers following booster vaccination. There were delays/reductions in antibody response to FHV-1, FeLV and rabies in treated cats; however, adequate protection was achieved in response to all booster vaccinations. Following primary vaccination with FIV, control cats showed a response, but treated cats showed no antibody production. Adverse events commonly associated with ciclosporin treatment, including diarrhea/loose stool, vomiting, salivation and regurgitation, were reported. In adult cats treated with 24 mg/kg/day of ciclosporin (more than three times the therapeutic dose), vaccine titer levels were adequate for protection following booster vaccination. In contrast, treated cats failed to mount a humoral response to a novel (FIV) vaccination, suggesting that memory B-cell immune responses remain intact during repeated high-dose ciclosporin administration in cats, but that primary immune responses are impaired.