A blinded, randomized, placebo-controlled trial of the safety of oclacitinib 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.

Oclacitinib therapy in two cats with refractory proliferative and necrotising otitis externa

Feline proliferative and necrotising otitis externa (PNOE) is a rare immune-mediated condition, usually self-limiting or responsive to immunosuppressants such as topical tacrolimus. This case report describes two cats with refractory PNOE that responded successfully to oclacitinib. One cat also had middle ear involvement and the other cat had extra-auricular dermatitis.

A Scoping Review on Tyrosine Kinase Inhibitors in Cats: Current Evidence and Future Directions

Tyrosine kinase inhibitors (TKIs) have become invaluable in the treatment of human and canine malignancies, but their role in feline oncology is less defined. While toceranib phosphate and masitinib mesylate are licensed for use in dogs, no TKI is yet approved for cats. This review systematically maps the research conducted on the expression of tyrosine kinases in neoplastic and non-neoplastic domestic feline tissues, as well as the in vitro/in vivo use of TKIs in domestic cats. We identify and discuss knowledge gaps and speculate on the further research and potential indications for TKI use in cats. A comprehensive search of three electronic databases and relevant paper reference lists identified 139 studies meeting the inclusion criteria. The most commonly identified tumors were mast cell tumors (MCTs), mammary and squamous cell carcinomas and injection-site sarcomas. Based on the current literature, toceranib phosphate appears to be the most efficacious TKI in cats, especially against MCTs. Exploring the clinical use of TKIs in mammary carcinomas holds promise. Despite the progress, currently, the evidence falls short, underscoring the need for further research to discover new indications in feline oncology and to bridge the knowledge gaps between human and feline medicine.

Efficacy of oclacitinib for the control of feline atopic skin syndrome: correlating plasma concentrations with clinical response

OBJECTIVES

The aim of this study was to assess the efficacy of a new therapeutic regimen of oclacitinib for the control of feline atopic skin syndrome (FASS) and to correlate plasma levels of this drug with clinical effects.

METHODS

Twenty-eight client-owned cats with a clinical diagnosis of FASS were recruited. Oclacitinib was administered at 1 mg/kg q12h for 2 weeks and then at 1 mg/kg q24h for a further 2 weeks. At the study outset (D0), and 7 (D7) and 28 (D28) days after starting treatment, clinical lesions were assessed using a validated scoring system (SCORing Feline Allergic Dermatitis [SCORFAD]) and pruritus was graded via an adapted visual analogue scale (PVAS). At the same time points, plasma oclacitinib levels and haematological variables were measured.

RESULTS

Among 18 cats completing the study, PVAS and SCORFAD improved by ⩾50% in 61% and 88% of animals, respectively. Mean PVAS decreased significantly between D0 and D7 and between D0 and D28 (both P <0.001) but not between D7 and D28. Likewise, mean SCORFAD values decreased significantly between D0 and D7 and between D0 and D28 (both P <0.001) but not between D7 and D28. On D7 and D28, plasma oclacitinib concentrations varied widely from 0 to 1443.2 ng/ml and from from 0 to 1177.7 ng/ml, respectively. Oclacitinib concentrations showed no correlation with clinical effects (SCORFAD and PVAS).

CONCLUSIONS AND RELEVANCE

Oclacitinib emerged as being safe and effective to control clinical signs of FASS. A mean dose of 1 mg/kg, even without extending twice-daily treatment beyond the first 2 weeks, could be a suitable therapeutic regimen. Plasma drug levels did not seem useful to predict clinical response during treatment.

Fatal disseminated toxoplasmosis in a feline immunodeficiency virus‐positive cat receiving oclacitinib for feline atopic skin syndrome

Toxoplasma gondii is a ubiquitous protozoan, for which felids are the definitive host. Immunocompromised individuals are susceptible to recrudescent toxoplasmosis. This case describes a 6‐year‐old, feline immunodeficiency virus‐positive domestic short hair cat with feline atopic skin syndrome that developed fatal toxoplasmosis after treatment with oclacitinib for five months.

The JAK/STAT signaling pathway: from bench to clinic

The Janus kinase/signal transducer and activator of transcription (JAK/STAT) signaling pathway was discovered more than a quarter-century ago. As a fulcrum of many vital cellular processes, the JAK/STAT pathway constitutes a rapid membrane-to-nucleus signaling module and induces the expression of various critical mediators of cancer and inflammation. Growing evidence suggests that dysregulation of the JAK/STAT pathway is associated with various cancers and autoimmune diseases. In this review, we discuss the current knowledge about the composition, activation, and regulation of the JAK/STAT pathway. Moreover, we highlight the role of the JAK/STAT pathway and its inhibitors in various diseases.

The JAK/STAT signaling pathway: from bench to clinic

The Janus kinase/signal transducer and activator of transcription (JAK/STAT) signaling pathway was discovered more than a quarter-century ago. As a fulcrum of many vital cellular processes, the JAK/STAT pathway constitutes a rapid membrane-to-nucleus signaling module and induces the expression of various critical mediators of cancer and inflammation. Growing evidence suggests that dysregulation of the JAK/STAT pathway is associated with various cancers and autoimmune diseases. In this review, we discuss the current knowledge about the composition, activation, and regulation of the JAK/STAT pathway. Moreover, we highlight the role of the JAK/STAT pathway and its inhibitors in various diseases.

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.

Idiopathic ulcerative dermatitis in a cat with feline infectious peritonitis

A 1-year-old, castrated, male, domestic short-haired cat with pruritic, multifocal, crusted ulceration of the skin over the dorsal aspect of the neck and scapulae was presented. The cat also had a history of depression and anorexia. A causative agent for the lesion was not identified on a general dermatological examination. Histopathology revealed diffuse epidermal ulceration and loss with replacement by neutrophilic inflammation and necrotic debris. Idiopathic ulcerative dermatitis (IUD) was diagnosed based on history, physical examination and histopathology. To prevent self-trauma and secondary bacterial infection, light bandages and glucocorticoid ointment were applied. After a month of management, the lesions markedly improved. Approximately 3 months after the initial presentation, the cat died; necropsy confirmed an IUD and non-effusive (dry form) feline infectious peritonitis (FIP). This report describes a rare case of IUD in a cat with concurrent FIP. However, no association between IUD and FIP was found.