Zoetis, Kalamazoo, MI, USA.
The Veterinary Consultancy, Woodcliff Lake, NJ, USA.
Parasit Vectors. 2019 Jul 26;12(1):369. doi: 10.1186/s13071-019-3632-3.
The efficacy of an extended-release injectable moxidectin (0.5 mg/kg) suspension (ProHeart® 12) (PH 12) in preventing the development of Dirofilaria immitis in dogs for 12 months was investigated in laboratory and field studies in the USA.
In each of two laboratory studies, 20 dogs ≥ 12 months of age were randomly allocated to receive a subcutaneous injection of saline or PH 12 on Day 0 and were then inoculated with 50 D. immitis third-stage larvae (L) on Day 365. All dogs were necropsied ~ 5 months post-inoculation for adult worm counts. The field efficacy study included dogs ≥ 10 months of age from 19 veterinary clinics in the USA treated with either 20 monthly doses of Heartgard® Plus (HG Plus) (296 dogs) or two doses of PH 12 (297 dogs) on Days 0 and 365. Efficacy was determined on Days 365, 480 and 605 using adult HW antigen and microfilaria testing to assess adult HW infection.
PH 12 was 100% effective in preventing HW disease in all three of these studies. In the laboratory studies, no PH 12-treated dogs had any adult HWs, whereas all control dogs in both studies had adult HWs [geometric mean, 30.2 (range, 22-37) for Study 1 and 32.6 (22-44) for Study 2]. In the field study, all dogs treated with PH 12 tested negative for adult HW infection on all test days (Days, 365, 480 and 605), whereas four dogs receiving HG Plus (positive control) tested positive for HWs during the study (three dogs on Day 365 and one dog on Day 480). All four dogs treated with HG Plus that subsequently tested positive for HWs during the field study were from the lower Mississippi River Valley region, where HW resistance to macrocyclic lactone preventives has been confirmed to occur. PH 12 was significantly better than HG Plus in preventing heartworm disease in the field study (P = 0.0367). PH 12 was well-tolerated in both laboratory and field studies.
A single dose of ProHeart® 12 was 100% effective in preventing heartworm disease in dogs for a full year in both laboratory and field studies.
在实验室和美国的实地研究中，已对一种新型的延长释放型米尔贝肟（0.5mg/kg）混悬注射液（ProHeart®12，PH12）预防犬心丝虫病（Dirofilaria immitis）发展的疗效进行了研究，其预防效果可长达 12 个月。
在两项实验室研究中，将 20 只年龄≥12 个月的犬随机分为两组，分别于第 0 天接受皮下注射生理盐水或 PH12，并于第 365 天接种 50 条犬心丝虫第三期幼虫（L）。所有犬于接种后约 5 个月进行剖检，以计数成虫数。在包括美国 19 家兽医诊所的实地疗效研究中，将年龄≥10 个月的犬随机分为两组，分别于第 0 天和第 365 天接受每月 20 次的 Heartgard®Plus（HG Plus，296 只犬）或 PH12 两次（297 只犬）治疗。使用犬心丝虫抗原和微丝蚴检测在第 365、480 和 605 天评估成年心丝虫感染，以确定疗效。
在这三项研究中，PH12 对预防 HW 疾病的有效性均达到 100%。在实验室研究中，所有 PH12 治疗组的犬均未检出任何成年 HW，而两项研究中的所有对照犬均有成年 HW（研究 1 的几何均数为 30.2[范围 22-37]，研究 2 为 32.6[22-44]）。在实地研究中，所有接受 PH12 治疗的犬在所有检测日（第 365、480 和 605 天）均检测为成年 HW 感染阴性，而接受 HG Plus（阳性对照）治疗的 4 只犬在研究期间检测为 HW 阳性（3 只犬于第 365 天，1 只犬于第 480 天）。在实地研究期间，所有随后检测为 HW 阳性的接受 HG Plus 治疗的犬均来自密西西比河下游流域，该地区已确认存在大环内酯类驱虫药预防心丝虫病的耐药性。PH12 在预防实地研究中的心丝虫病方面明显优于 HG Plus（P=0.0367）。PH12 在实验室和实地研究中均具有良好的耐受性。
在实验室和实地研究中，单次使用 ProHeart®12 预防犬心丝虫病的效果均达到 100%，有效期长达 1 年。
