Cyclosporine decreases skin lesions and pruritus in dogs with atopic dermatitis: a blinded randomized prednisolone-controlled trial

During the last decade, oral cyclosporin (CsA) has proven to be effective, in randomized controlled trials, for the treatment of atopic dermatitis (AD) in human patients. The purpose of this blinded randomized controlled trial was to test the hypothesis that CsA was successful in reducing the gravity of clinical signs of AD in dogs. Thirty dogs with nonseasonal AD were randomly allocated to receive an oral solution of either NEORAL CsA (5 mg kg-1) or prednisolone (0.5 mg kg-1) once daily for 6 weeks. Before, and 3 and 6 weeks after therapy, skin lesions were graded by clinicians using the Canine AD Extent and Severity Index (CADESI). Pruritus was assessed by the owners using a visual analog scale (PVAS). In both groups, CADESI and PVAS values were significantly lower at 6 weeks post treatment than before the initiation of therapy (Friedman test, P < 0.0004). The percentage reductions in CADESI and PVAS values from baseline were not statistically different between groups (Mann-Whitney test, P > 0.3). In this experiment, the tolerability and safety of oral CsA and prednisolone appeared similar. One-fifth of dogs given oral CsA occasionally developed diarrhoea or soft stools. One dog that was given CsA developed a generalized papillomatous skin eruption during the second half of the trial. Our study provides randomized controlled trial evidence that CsA reduces the severity of clinical signs in dogs with nonseasonal AD. Moreover, the anti-allergic efficacy of CsA appears comparable with that of prednisolone. We propose that oral CsA should be considered as a valuable alternative to glucocorticoid therapy in dogs with AD.     

Treatment of localized lesions of canine atopic dermatitis with tacrolimus ointment: a blinded randomized controlled trial

This investigator-blinded randomized controlled trial was designed to determine whether tacrolimus ointment (Protopic, Fujisawa Healthcare) decreased the severity of localized lesions of canine atopic dermatitis (AD). Twenty dogs with AD were enrolled if they exhibited lesions on both front metacarpi. Each foot was randomized to be treated with 0.1% tacrolimus or placebo (vaseline) ointment twice daily for 6 weeks. Before, and every 2 weeks during the study, erythema, lichenification, oozing and excoriations each were graded on a 10-point scale (maximal total score: 40). The primary outcome measures were the percentage reduction from baseline of lesional scores and the number of subjects whose scores had decreased by 50% or greater at study end. Intention-to-treat analyses were used. At study onset, lesional scores were not significantly different between sites treated with tacrolimus or placebo. After 6 weeks, the percentage reduction from baseline scores was higher for tacrolimus-treated sites (median: 63%; 95% confidence interval: 39-67) than for placebo-treated feet (median: 3%; confidence interval: -2-13) (Wilcoxon test; P = 0.0003). When tacrolimus was applied, lesions decreased by 50% or greater in 15/20 dogs (75%); these dogs were those that completed the study. In contrast, this benchmark was not reached for any placebo-treated feet (Fisher's test; P < 0.0001). Adverse drug events consisted of minor irritation in some lesional areas treated with tacrolimus. Results of this trial suggest that the application of 0.1% tacrolimus ointment is useful for reducing the severity of localized skin lesions of canine AD.     

P‐48 Treatment of localized lesions of canine atopic dermatitis with tacrolimus ointment: a blinded,randomized, controlled trial

The purpose of this study was to determine whether tacrolimus ointment (Protopic) decreased the severity of localized lesions of canine atopic dermatitis (AD). Twenty dogs with AD were enrolled if they exhibited skin lesions localized to both front metacarpi. Each foot was randomized to be treated either with 0.1% tacrolimus or placebo (vaseline) ointment twice daily for 6 weeks. The nature of treatment for each foot lesion was concealed from the clinician. Before, and every 2 weeks during the study, erythema, lichenification, oozing and excoriations each were graded on a 10‐point scale (maximal total score: 40). The primary outcome measures consisted of the percentage reduction from baseline of lesional scores, and the number of subjects whose scores had decreased by 50% or greater by the end of the study. Intent‐to‐treat analyses were used. At the beginning of the study, lesional scores were not significantly different between treatment groups. After 6 weeks, the percentage reduction from baseline scores was higher for tacrolimus‐treated sites [median: 63% (95% CI: 39–67)] than for placebo‐treated feet [3% (‐2‐13)] (paired t‐test; P < 0.0001). When tacrolimus was applied, lesions decreased by 50% or greater in 15 dogs (75%), while this benchmark was not reached for any placebo‐treated feet (Fisher's exact test; P < 0.0001). Adverse drug events consisted of minor irritation in some dogs treated with tacrolimus. Results of this randomized, controlled trial suggest that the daily application of 0.1% tacrolimus ointment is useful for reducing the severity of localized skin lesions of canine AD. Funding: Self‐funded.     

FC‐39 Successful management of canine atopic dermatitis using a plant extract: a randomized,double‐blinded,placebo‐controlled trial

This study evaluated the efficacy of Phytopica^TM, a proprietary blend of standardised plant extracts, in canine atopic dermatitis (AD). One hundred twenty dogs with perennial AD were recruited on the basis of history and clinical signs, and a positive intradermal allergen test or rFcεRIα serology to perennial allergens. Other pruritic dermatoses were eliminated by antimicrobial treatment, skin scrapings, Sarcoptes serology, flea control and a 6‐week food trial. Exclusion criteria included antimicrobial therapy within 7 days, antihistamines within 14 days, oral/topical glucocorticoids or cyclosporin within 28 days, and parenteral glucocorticoids, essential fatty acids or immunotherapy within 56 days of entry into the study. Dogs [minimum Canine Atopic Dermatitis Extent and Severity Index (CADESI) = 25] were randomly allocated to receive placebo, 100, 200 or 400 mg/kg Phytopica^TM daily for 12 weeks. Their CADESI was assessed every 4 weeks. A modified intention‐to‐treat population was analysed. The mean reductions in CADESI scores at the end of treatment compared to baseline were 4.4% (100 mg/kg; n = 30), 23.4% (200 mg/kg; n = 29, P < 0.01), 8.5% (400 mg/kg; n = 29) and 3.9% (placebo; n = 29). For more severely affected dogs (minimum CADESI ≥ 50 at baseline), there was significant reduction in mean CADESI score (29.3%, P = 0.038) only in the 200 mg/kg treatment group (n = 14). In conclusion, this study demonstrates that Phytopica^TM is an effective nonsteroidal treatment for canine AD. Funding: Phytopharm plc.     

Intradermal injection of heat-killed Mycobacterium vaccae in dogs with atopic dermatitis: a multicentre pilot study

Canine atopic dermatitis (cAD) is a common disease with a multifactorial aetiology associated with impaired immunoregulation. The immunopathogenesis has similarities to that of human atopic dermatitis. Clinical signs of allergic disease in humans and mice are reduced by administration of saprophytic mycobacteria that amplify regulatory cytokines and hence the effect of Mycobacterium vaccae on the clinical severity of cAD was investigated. Sixty-two dogs with cAD, selected according to strict criteria, were treated with a single intradermal injection and evaluated monthly for 3 months in a placebo-controlled double-blind clinical trial. Clinical severity was quantified using standardized scores and by owner assessment of pruritus. A single injection of a heat-killed suspension of M. vaccae was found to be well tolerated and effective in treating mild to moderate cases of cAD demonstrable for 3 months, but was insignificant in more severely affected dogs.     

Common allergens of atopic dermatitis in dogs: comparative findings based on intradermal tests

Intradermal tests were performed on 58 dogs diagnosed with atopic dermatitis from 2004~2008 at the Veterinary Medical Teaching Hospital of Konkuk University, Korea. To compare the allergen distribution observed in the present investigation to the results from other studies conducted in Korea and elsewhere, the allergens were grouped according to their kinds. There was no significant difference in gender distribution among the dogs. The most common breeds among the 58 dogs were Maltese (n = 11) and Shih-tzu (n = 11). The average age was 4.8 years. The most frequently produced a positive reaction on the intradermal tests was mold (67.3%) followed by house dust (54.5%) and house dust mites (49.1%). The present study found a low distribution of dogs allergic to various outdoor allergens compared to studies performed in other countries; this may reflect differences in living conditions for dogs living in Korea.     

Masitinib for the treatment of canine atopic dermatitis: a pilot study

There is an on-going need to identify medications suitable for the long-term treatment of canine atopic dermatitis (CAD). Masitinib mesilate is a potent and selective tyrosine kinase inhibitor of the c-KIT receptor. A strong relationship exists between the SCF/c-KIT pathway and pathogenesis of CAD, suggesting that masitinib may potentially fulfil the above role. This study reports on an uncontrolled pilot study of masitinib in CAD. Masitinib was administered orally to 11 dogs at a mean dose of 11.0 ± 1.83 mg/kg/day (free base) for 28 days. Treatment response was assessed by evolution of clinical appearance according to a modified version of the Canine Atopic Dermatitis Extent and Severity Index (mCADESI), pruritus scale and surface area of lesions. Masitinib improved CAD with a mean reduction in mCADESI of 50.7 ± 29.8% (95% C.I. = 29.4–72.0; p = 0.0004) at day 28 relative to baseline, with 8/10, 8/10 and 4/10 dogs showing improvement of ≥33%, ≥40% and ≥50%, respectively. Improvement was further evidenced by a decrease in pruritus score and the surface area of lesions. No serious or severe adverse events occurred during this trial, although 6/11 dogs presented with mild to moderate treatment related adverse events. There is sufficient compelling evidence to warrant further investigation.