Age- and breed-matched retrospective cohort study of malignancies and benign skin masses in 660 dogs with allergic dermatitis treated long-term with versus without oclacitinib

Potential applications of JAK inhibitors, clinically approved drugs against autoimmune diseases, in cancer therapy

Disturbances in immunoregulation may lead to both cancer and autoimmune diseases. Many therapeutic drugs for autoimmune diseases also display anti-tumor efficacy. The Janus kinase/signal transducer and activator of transcription signaling pathways are involved in the secretion of more than 50 distinct cytokines, which have critical roles in inducing autoimmune diseases and tumorigenesis. Thus, Janus kinases have become classical immunotherapeutic targets for immune disease. More than 70 Janus kinase inhibitors have been approved as immunomodulatory drugs for clinical use, of which 12 are used in the treatment of autoimmune diseases. This systematic review aims to elucidate the anti-tumor role of clinically approved Janus kinase inhibitors that were primarily designed for the treatment of autoimmune diseases and their potential for clinical translation as cancer treatments.

The use of oclacitinib compared to azathioprine in the management of canine pemphigus foliaceus: A retrospective analysis

BACKGROUND

Oclacitinib (Apoquel; Zoetis) has been reported to be beneficial for treating immune-mediated disorders.

HYPOTHESIS/OBJECTIVES

This retrospective study evaluates in which group of dogs [oclacitinib (OC) or azathioprine (AZ)] remission of pemphigus foliaceus (PF) was more effectively achieved with matched induction dosing of glucocorticoids; it further evaluates which group had a higher glucocorticoid-sparing effect.

ANIMALS

Review of 30 medical records of dogs diagnosed with PF presented to a private practice dermatological service.

MATERIALS AND METHODS

Retrospective analysis of dogs diagnosed with PF and treated with OC or AZ in combination with glucocorticoids.

RESULTS

There was no significant difference in the ability to induce remission between AZ and OC groups. In the AZ group, 13 of 15 dogs went into some type of remission (partial or complete), compared with 11 of 15 in the OC group. There was no significant difference between the two groups for the glucocorticoid-sparing effect. The AZ group had an average reduction of 77.9% from the induction glucocorticoid dose, and OC group had an average reduction of 64.4%. One of 15 patients in the AZ group and three of 15 patients in the OC group had a 100% reduction of the glucocorticoid dose.

CONCLUSIONS AND CLINICAL RELEVANCE

These results indicate that OC can be considered as a treatment option for canine PF.

A review of cutaneous hypersensitivity reactions in dogs: A diagnostician's guide to allergy

Allergic dermatoses are common in people and domestic animals. Resultant lesions are routinely biopsied and submitted for histological examination to confirm a diagnosis or rule out diseases with overlapping or atypical clinical features. Diagnostic pathologists and clinicians are often faced with the difficult task of determining whether an allergic reaction pattern is present on both the microscopic and macroscopic levels and correlating histopathologic findings with clinical and historical data to achieve a precise clinical diagnosis. The bulk of the current veterinary literature on allergic dermatoses focuses on atopic dermatitis in dogs, distantly followed by cats, horses, and other animals. The objectives of this review are to demonstrate the key histopathologic and clinical diagnostic features of the various allergy-mediated reaction patterns, and to provide diagnosticians with a practical guide for clinicopathological correlations. Current concepts in the pathophysiology of immediate hypersensitivity reactions, with a focus on atopic dermatitis, are discussed. Points of potential histopathologic overlap between the "classic" allergic reaction pattern and less common inflammatory, predominately eosinophilic, conditions that may mimic this pattern will be discussed with the goal of highlighting the critical need for collaboration between pathologists and clinicians in furthering patient care.

Effective treatment of canine chronic cutaneous lupus erythematosus variants with oclacitinib: Seven cases

BACKGROUND

The treatment of canine chronic cutaneous lupus erythematosus (CCLE) variants generally requires immunosuppression, which often results in potentially severe adverse effects. Janus kinase inhibitors, like oclacitinib, might be a valuable treatment option due to their rapid inhibition of the action of interferons known to be relevant in the pathogenesis of CCLE.

OBJECTIVES

To report the efficacy and safety of oral oclacitinib for the treatment of canine CCLE variants.

ANIMALS

Seven dogs were diagnosed with CCLE based on clinical signs and compatible histopathological findings.

MATERIALS AND METHODS

Oclacitinib was administered at the induction dosage of 0.45 mg/kg twice daily to 1.8 mg/kg once daily. The response to treatment was graded as 'good' when there was ≥50% lesion reduction, or as 'complete remission' if all active lesions had resolved. Complete blood counts were performed at variable intervals.

RESULTS

A complete remission of all lesions was obtained in the dog with exfoliative cutaneous lupus erythematosus, both dogs with mucocutaneous lupus erythematosus and three of four dogs with facial discoid lupus erythematosus (FDLE); a good response was seen in the remaining dog with FDLE. The first visible improvement of signs was seen within 2-to-3 weeks, while the time to complete remission was around 2 months. Clinical adverse effects were not seen, and haematological parameters remained within the reference range.

CONCLUSIONS AND CLINICAL RELEVANCE

Oclacitinib may be considered an effective treatment option for different variants of canine CCLE.

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.

Prolonged twice-daily administration of oclacitinib for the control of canine atopic dermatitis: a retrospective study of 53 client-owned atopic dogs

BACKGROUND

Oclacitinib administered at the licensed dose twice daily for two weeks and then once daily as required is recommended for the treatment of atopic dogs. In some cases, the once-daily regimen is insufficient to control the clinical signs.

OBJECTIVES

To provide preliminary safety and efficacy data on the prolonged twice-daily administration of oclacitinib in atopic dogs.

ANIMALS

Fifty-three client-owned atopic dogs.

METHODS AND MATERIALS

The medical records of dogs with atopic dermatitis treated with oclacitinib twice daily for more than two weeks were reviewed retrospectively. Animal details, treatment dose and duration, concurrent diseases, adjunctive medications and possible adverse events were recorded. Treatment efficacy was assessed retrospectively and, when available, the selected blood parameters before and during the treatment were compared. Statistical analyses of the collected data were performed.

RESULTS

The median treatment duration was 113 days. Excellent-to-good efficacy was observed in 38 dogs (72%), including 24 of 33 dogs that failed to respond to the once-daily regimen. Eight dogs showed a poor response despite the addition of systemic glucocorticoids. Pyoderma, gastrointestinal signs and otitis externa were the most frequent adverse events recorded whilst on treatment. Blood tests performed in 35 dogs showed slightly decreased leucocyte, neutrophil, eosinophil and monocyte counts that remained within the reference ranges in most cases. Three dogs developed hypercholesterolemia.

CONCLUSIONS AND CLINICAL RELEVANCE

Prolonged twice-daily administration of oclacitinib generally was well-tolerated and was effective in most of the treated dogs. Regular clinical evaluation and blood tests are advisable for this treatment regimen.

Immunomodulatory effect of long-term oclacitinib maleate therapy in dogs with atopic dermatitis

BACKGROUND

Canine atopic dermatitis (cAD) is a chronic disease characterised by hypersensitivity to environmental allergens. Oclacitinib maleate selectively inhibits pro-inflammatory mediators associated with cAD. However, the impact of chronic oclacitinib use on immunocompetence requires further investigation.

OBJECTIVES

Herein, we examined the potential immunomodulatory effects of prolonged oclacitinib treatment in dogs.

ANIMALS

Thirteen privately owned dogs with cAD, treated with 0.4-0.6 mg/kg oclacitinib for 12 months.

METHODS AND MATERIALS

Pruritus level was evaluated using a pruritus Visual Analog Scale (pVAS) and the canine atopic dermatitis extent and severity index, 4^th iteration (CADESI IV). Peripheral blood samples were collected for routine laboratory assays and lymphocyte subtypes were analysed using flow cytometry. Antigen-specific intracellular cytokine production from CD4+ and CD8+ T lymphocytes was analysed following in vitro stimulation by Dermatophagoides farinae antigens.

RESULTS

Oclacitinib treatment significantly reduced pVAS and CADESI-04 scores, by 51% and 86.7%, respectively. Flow cytometric analysis revealed increased CD4+ and CD14+ lymphocyte populations. The cytokine profile at 360 days after treatment initiation was similar to that before treatment and was not associated with clinical relapse.

CONCLUSION

Oclacitinib, when administered at the currently labelled dose for one year, is associated with a significant increase in circulating CD4+ T cells, but does not alter cytokine production from antigen-stimulated T cells. The results reported do not support evidence for immunosuppression mediated by the mechanisms evaluated in this study.