Table 3.

Arithmetic mean tick counts and percent efficacy relative to placebo for dogs following one oral treatment with Simparica Trio™ with existing Dermacentor variabilis infestations and after subsequent weekly re-infestations

Study	Tick strain	Daya	Placebob		Simparica Trio™b		% Efficacy	Test statistic
			Mean	Range	Mean	Range
5	Oklahoma State Universityc	2	34.0	20–44	0.1	0–1	99.7	t(9.02) = 11.57, P < 0.0001
		7	39.8	29–50	0.4	0–3	99.0	t(9) = 20.32, P < 0.0001
		14e	39.1	30–46	0.1	0–1	99.7	t(8.06) = 23.79, P < 0.0001
		21e	30.4	16–42	1.1	0–6	96.4	t(8.06) = 11.16, P < 0.0001
		28e	31.2	23–42	2.3	0–19	92.6	t(8.59) = 15.04, P < 0.0001
		35e	31.6	24–41	4.2	0–27	86.7	t(8.68) = 10.59, P < 0.0001
6	Ecto Services Incd	2	26.8	16–42	0.3	0–2	98.9	t(9.17) = 11.91, P < 0.0001
		7	19.7	14–31	0.2	0–1	99.0	t(9.09) = 10.55, P < 0.0001
		14	28.7	10–48	0.5	0–2	98.3	t(9) = 8.16, P < 0.0001
		21	30.4	20–38	0	0–0	100	t(9) = 17.67, P < 0.0001
		28	31.1	22–41	0	0–0	100	t(9) = 14.56, P < 0.0001
		35	28.0	12–51	0.4	0–2	98.6	t(9) = 7.79, P < 0.0001

^aFirst infestation on Day -2. Subsequent infestations on Day 5, 12, 19, 26 and 33. Tick counts were conducted at 48 hours post-treatment and weekly re-infestation

^bTreatment with placebo or Simparica Trio™ (minimum dose 1.2 mg/kg sarolaner, 24 µg/kg moxidectin and 5 mg/kg pyrantel (as pamoate salt)) occurred on Day 0

^cColony originated from ticks field-collected in Stillwater, OK, USA, in 1972 and was last supplemented with wild-caught ticks the same year as the study started

^dColony started from ticks field-collected in Stillwater, OK, USA, in 2015 (one year prior to study start)

^eStudy 5: Time-points with missing observations (Days 14–35) used least squares means and corresponding % efficacies