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 L₃ (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是一种局部杀菌剂，掺有6 mg / kg的selamectin和1 mg / kg的sarolaner，已批准用于猫中，以预防丝虫病。赛拉菌素的功效先前尚未针对猫中任何抗大环内酯（ML）的丝虫菌株进行评估，以预防丝虫病。在这项研究中，塞拉菌素的实验组合制剂（6毫克/千克）加sarolaner（2毫克/千克）进行了评估，用于防止的ML-抗性菌株的发展犬恶丝虫在猫。

使用了40只7至9个月大的家养短毛猫（20例雄性； 20例雌性），并且在纳入研究前心丝虫抗原呈阴性。在第-30天，给猫接种100 D. L ₃炎症（ZoeMO毒株）腹股沟皮下注射。将猫随机分配至以下四个具有相关给药方案的治疗方案之一：T01（在第0、28和56天接受车辆治疗的对照），T02（仅在第0天接受单剂量的selamectin加sarolaner组合），T03（selamectin）加上第0、28和56天的sarolaner组合）或T04（仅限第0天的单剂量塞拉菌素）。所有治疗均以基于异丙醇的制剂局部给药。分离和组合制剂均以6 mg / kg的剂量施用Selamectin。Sarolaner的剂量为2 mg / kg。在〜145天（感染后〜175天）对猫进行尸检，并计数成虫。

对照组（T01）的十只猫中有九只被成虫感染（范围1-23；几何平均值3.5）。相反，T03中的所有猫的心丝虫为零。T02（0-3; 0.2）中只有两只猫，而T04（0-1; 0.1）中只有一只猫患有丝虫。与T01（对照组猫）相比，所有处理过的猫的蠕虫负担均显着降低（p <0.0001），治疗效率分别为100％（T03），93.5％（T02）和98％（T04）。

将塞拉菌素（6 mg / kg）与sarolaner（2 mg / kg）局部联合使用时，连续三个月治疗，可预防猫对ML耐药的D.炎性线虫（ZoeMO）菌株的发展。单一剂量很高（93.5％），但效果不完全。