Zoetis, Veterinary Medicine Research and Development, 333 Portage Street Kalamazoo, MI 49007, USA.
Zoetis, Veterinary Medicine Research and Development, 333 Portage Street Kalamazoo, MI 49007, USA.
Vet Parasitol. 2020 Jun;282:109122. doi: 10.1016/j.vetpar.2020.109122. Epub 2020 May 11.
Revolution®/Stronghold® Plus, a topical endectocide incorporating 6 mg/kg selamectin plus 1 mg/kg sarolaner, is approved for use in cats to prevent heartworm disease. The efficacy of selamectin has not previously been evaluated against any macrocyclic lactone (ML)-resistant heartworm strains in cats for prevention of heartworm disease. In this study, an experimental combination formulation of selamectin (6 mg/kg) plus sarolaner (2 mg/kg) was assessed for preventing the development of a ML-resistant strain of Dirofilaria immitis in cats. Forty purpose-bred domestic shorted-haired cats (20 males; 20 females) from 7-9 months of age and negative for heartworm antigen prior to study inclusion were used. On Day -30, cats were inoculated with 100 D. immitis L (ZoeMO strain) subcutaneously in the inguinal area. Cats were randomly allocated to one of the following four treatments with associated dosing regimens: T01 (vehicle-treated control on Days 0, 28, and 56), T02 (single dose of selamectin plus sarolaner combination on Day 0 only), T03 (selamectin plus sarolaner combination on Days 0, 28, and 56) or T04 (single dose of selamectin on Day 0 only). All treatments were administered topically in an isopropyl alcohol-based formulation. Selamectin was administered at 6 mg/kg in both standalone and combination formulations. Sarolaner was administered at 2 mg/kg. Cats were necropsied on Day ∼145 (∼175 days post infection) and adult worms were counted. Nine of ten cats in the control group (T01) were infected with adult worms (range, 1-23; geometric mean, 3.5). In contrast, all cats in T03 had zero heartworms. Only two cats in T02 (0-3; 0.2) and a single cat in the T04 (0-1; 0.1) had heartworms. Compared to T01 (control cats), all treated cats had significantly (p < 0.0001) reduced worm burdens, with treatment efficacies of 100% (T03), 93.5% (T02) and 98% (T04). A topical combination of selamectin (6 mg/kg) plus sarolaner (2 mg/kg) was 100% efficacious in preventing the development of an ML-resistant strain of D. immitis (ZoeMO) in cats when administered as three consecutive monthly treatments. A single dose was highly (93.5%) but incompletely effective.
Revolution®/Stronghold® Plus 是一种局部用的驱虫药，包含 6 毫克/千克的塞拉菌素和 1 毫克/千克的萨罗拉纳，获批用于预防猫的心脏蠕虫病。塞拉菌素的疗效以前并未针对猫的任何大环内酯类（ML）耐药性心脏蠕虫菌株进行过评估，以预防心脏蠕虫病。在这项研究中，评估了一种塞拉菌素（6 毫克/千克）加萨罗拉纳（2 毫克/千克）的实验组合配方，以预防猫的 ML 耐药性犬恶丝虫感染。40 只专门饲养的家养短毛猫（20 只雄性；20 只雌性），年龄在 7-9 个月，在研究开始前均为心脏蠕虫抗原阴性。在第-30 天，将 100 条犬恶丝虫 L（ZoeMO 株）皮下接种到腹股沟区域。猫被随机分配到以下四种治疗组之一，并进行相关剂量方案治疗：T01（第 0、28 和 56 天给予安慰剂）、T02（第 0 天给予塞拉菌素加萨罗拉纳组合的单剂量）、T03（第 0、28 和 56 天给予塞拉菌素加萨罗拉纳组合）或 T04（第 0 天给予塞拉菌素的单剂量）。所有治疗均以异丙醇为基础的制剂进行局部给药。塞拉菌素在单独使用和组合制剂中的剂量均为 6 毫克/千克。萨罗拉纳的剂量为 2 毫克/千克。猫在大约 145 天（感染后大约 175 天）进行尸检，计数成虫。对照组（T01）中的 10 只猫中有 9 只（范围为 1-23；几何平均值为 3.5）感染了成虫。相比之下，T03 组中的所有猫均未发现心虫。T02 组中只有 2 只猫（0-3；0.2）和 T04 组中的 1 只猫（0-1；0.1）有心虫。与 T01（对照组猫）相比，所有接受治疗的猫的蠕虫负担均显著（p<0.0001）降低，治疗效果分别为 100%（T03）、93.5%（T02）和 98%（T04）。当作为连续三个月的三次治疗时，塞拉菌素（6 毫克/千克）加萨罗拉纳（2 毫克/千克）的局部联合使用对预防猫的 ML 耐药性犬恶丝虫（ZoeMO）的发生具有 100%的疗效。单次剂量的疗效非常高（93.5%）但不完全。
