Atopic dermatitis (AD) is the most frequent allergic disease in dogs. AD can be treated using allergenspecific immunotherapy as well as symptomatic antipruritic treatment including the use of lokivetmab - caninized anti-interleukine-31 antibody.

The aim of the study was to evaluate the effectiveness of lokivetmab over 12 weeks of treatment. Studies have been carried out in 89 dogs. In all affected animals, the severity of lesions was assessed using the CADESI 04 and the pruritus was assessed using the VAS.

After the first dose of lokivetmab, both CADESI 04 and VAS statistical decreased by 4 weeks from 40.48 to 20.31, and from 7.42 to 2.48, respectively (p = 0.0000001) maintained significantly decresed values during the whole treatment period (CADESI 04 15.64, 15.07 after 8 and 12 weeks, respectively, PVAS 2.03, 1.95 after 8 and 12 weeks, respectively).

Lokivetmab leads to a significant reduction of CADESI 04 and pruritus, within four weeks and maximum effect is achived after the second dose.

Studies on serum interleukin (IL)-31 levels in dogs with atopic dermatitis (AD) and their correlation with disease severity are limited. To the author’s knowledge, there are no studies that measured serum IL-31 in dogs treated with lokivetmab injections, a selective inhibitor of this key cytokine in pruritus. The aim of the study was to evaluate serum IL-31 levels in dogs treated with lokivetmab and correlate it with the severity of canine atopic dermatitis using the pruritus visual analog scale (pVAS) and canine atopic dermatitis extent and severity index (CADESI-04). Ten client-owned dogs diagnosed with AD received two injections of lokivetmab four weeks apart. Disease severity was assessed using the pVAS and CADESI-04 scores before and after both injections. In addition, canine serum IL-31 levels were measured at the same moments. Serum IL-31 was detected in all dogs in the study. There was a significant reduction in pVAS scores and serum IL-31 after administrations. However, there was no difference in CADESI-04 scores, and there was no significant correlation between CADESI-04 scores and serum IL-31 in dogs diagnosed with AD. Nonetheless, a significant positive correlation was observed between the pVAS scores and serum IL-31 levels with lokivetmab therapy, which reinforces the role of IL-31 in the pathogenesis of pruritus in dogs with AD. The data presented here provide further evidence that IL-31 is directly involved in pruritus pathogenesis in dogs with AD. In addition, blocking IL-31 has a significant antipruritic effect, but has no influence on skin lesion severity and extension.