ArticleParasites & vectors2026
Comparative efficacy of six monthly doses of Simparica Trio
Article in Parasites & vectors, 2026. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Not yet cited in PubMed.
What it found
Each row is one number read from the abstract, on the scale the paper reported it, with its interval. Left of the dashed line favours the treatment, right favours the comparator. Under each row is the sentence it came from. New to these charts? A ten-minute tutorial.
The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.
The trial behind it
Trials whose registry record cites this paper, or whose number appears in the abstract. A trial that started after this paper was published is citing it as background, not reporting it.
Neither the registry nor the abstract names a trial number. If this is a trial report, that itself is worth knowing.
Who cites it
0 citing papers in PubMed.
No citing paper in PubMed yet.
Corrections and comments
PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.
Authors and funding
8 authors.
Funding
No grant is acknowledged in the PubMed record.
Abstract
backgroundThe emergence of macrocyclic lactone (ML)-resistant Dirofilaria immitis highlights the need for informed and considered use of currently available heartworm preventives. Moxidectin provides robust protection against multiple ML-resistant D. immitis isolates, with efficacy dependent upon both the dosage and the number of monthly treatments administered. In this study the efficacy of six monthly treatments of Simparica Trio
methodsA total of 24 dogs were randomly allocated to negative control, NexGard Plus, or Simparica Trio groups. Each dog was inoculated with 50 ML-resistant D. immitis L3 larvae (ZoeLA isolate) on day -30. All dogs were dosed orally on days 0, 30, 60, 90, 120, and 150. Upon study completion (day 237), all adult worms were recovered and counted.
resultsMean moxidectin dosages administered to each group were 17.6 ± 1.6 µg/kg for NexGard Plus and 37.9 ± 8.4 µg/kg for Simparica Trio. Geometric mean (GM) adult worm counts in both NexGard Plus (0.7) and Simparica Trio (0.2) groups were significantly lower than negative control (P < 0.0001), with NexGard Plus and Simparica Trio providing 98.1% and 99.5% efficacy, respectively. However, D. immitis adult worms were recovered in 6/8 (75%) NexGard Plus-treated dogs compared with 2/8 (25%) Simparica-Trio-treated dogs, and the GM worm counts were significantly lower (P = 0.0316) in Simparica-Trio-treated dogs. Additionally, four (50%) dogs treated with NexGard Plus were positive for D. immitis antigen, and one of these four was microfilaremic. In contrast, in the Simparica-Trio-treated group, a single dog was positive for D. immitis antigen, and all eight dogs were amicrofilaremic.
conclusionsSix consecutive administrations of the higher label dosage of moxidectin delivered by Simparica Trio (24-48 µg/kg) protected more dogs from infection with the ML-resistant D. immitis isolate ZoeLA than the lower label dosage of moxidectin provided by NexGard Plus (12 - 24 µg/kg).
Indexed as
Identifiers
What OpenQuestion holds
Registered trials
Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.