BRAVECTO^® PROFESSIONAL RESOURCES

Abstract

Background: Fluralaner is a novel systemic ectoparasiticide for dogs providing immediate and persistent flea, tick and mite control after a single oral dose. Ivermectin has been used in dogs for heartworm prevention and at off label doses for mite and worm infestations. Ivermectin pharmacokinetics can be influenced by substances affecting the p-glycoprotein transporter, potentially increasing the risk of ivermectin neurotoxicity. This study investigated ivermectin blood plasma pharmacokinetics following concurrent administration with fluralaner.

Findings: Ten Beagle dogs each received a single oral administration of either 56 mg fluralaner (Bravecto™), 0.3 mg ivermectin or 56 mg fluralaner plus 0.3 mg ivermectin/kg body weight. Blood plasma samples were collected at multiple post-treatment time points over a 12-week period for fluralaner and ivermectin plasma concentration analysis.

Ivermectin blood plasma concentration profile and pharmacokinetic parameters C_max, t_max, AUC_∞ and t½ were similar in dogs administered ivermectin only and in dogs administered ivermectin concurrently with fluralaner, and the same was true for fluralaner pharmacokinetic parameters.

Conclusions: Concurrent administration of fluralaner and ivermectin does not alter the pharmacokinetics of either compound. Based on the plasma pharmacokinetic profile and the clinical observations, there is no evident interaction between fluralaner and ivermectin, and co-administration does not increase the risk of ivermectin associated neurotoxicity.

Keywords: Fluralaner, Bravecto™, Ivermectin, Dog, Pharmacokinetic, P-glycoprotein, MDR1

Abstract

Background: Fluralaner is a novel systemic insecticide and acaricide. The purpose of these studies was to investigate the pharmacokinetic properties of fluralaner in Beagle dogs following single oral or intravenous (i.v.) administration.

Methods: Following the oral administration of 12.5, 25 or 50 mg fluralaner/kg body weight (BW), formulated as chewable tablets or i.v. administration of 12.5 mg fluralaner/kg BW, formulated as i.v. solution to 24 Beagles, plasma samples were collected until 112 days after treatment. Plasma concentrations of fluralaner were measured using HPLC-MS/MS. Pharmacokinetic parameters were calculated by non-compartmental methods.

Results: After oral administrarion, maximum plasma concentrations (C) were reached within 1 day on average. Fluralaner was quantifiable in plasma for up to 112 days after single oral and i.v. treatment. The apparent half-life of fluralaner was 12–15 days and the mean residence time was 15–20 days. The apparent volume of distribution of fluralaner was 3.1 L/kg, and clearance was 0.14 L/kg/day.

Conclusions: Fluralaner is readily absorbed after single-dose oral administration, and has a long elimination half-life, long mean residence time, relatively high apparent volume of distribution, and low clearance. These pharmacokinetic characteristics help to explain the prolonged activity of fluralaner against fleas and ticks on dogs after a single oral dose.

Keywords: Fluralaner, Pharmacokinetics, Dog, Oral, Intravenous

Abstract

Background: Fluralaner is a novel systemic ectoparasiticide for dogs providing long-acting flea- and tick-control after a single oral dose. The pharmacokinetics of orally administered drugs may be influenced by feeding. This study investigated the influence of concurrent feeding on fluralaner pharmacokinetics.

Methods: Twelve fasted or fed beagles received a single oral administration of 25 mg fluralaner/kg body weight in a chewable tablet. Plasma samples were collected at multiple post-treatment time points for fluralaner concentration analysis. Clinical observations were performed on all dogs at regular intervals throughout the study.

Results: Fluralaner was readily absorbed in fasted and fed dogs administered at a dose of 25 mg/kg BW with a similar mean t_max for both groups. In fed dogs, AUC and C_max were increased compared to fasted dogs by a factor of 2.5 and 2.1 respectively. The difference in AUC and C_max between the fed and fasted groups was statistically significant. No adverse events were observed following oral fluralaner administration to fasted and fed dogs.

Conclusions: Fluralaner is absorbed to a considerable extent in fasted and fed dogs. Administration of fluralaner chewable tablets with food significantly increases bioavailability.

Keywords: Fluralaner, Dog, Pharmacokinetics, Food effect, Fasted

Abstract

Background: Fluralaner is a potent insecticide and acaricide with rapid and persistent efficacy. This study measured the efficacy of fluralaner flavored chews (Bravecto^®, Merck Animal Health) administered to dogs against adult Ctenocephalides felis felis and egg production.

Methods: Twelve purpose-bred dogs were randomly allocated to two groups of six dogs each. Dogs in treatment group 1 were administered a single fluralaner flavored chew to achieve a minimum dose of at least 25 mg/kg while treatment group 2 served as untreated controls. On Days −2, 28, 56, 84, 91, 98, 105, 112, and 120 post-treatment, each dog was infested with approximately 200 unfed cat fleas, C. felis felis (KS1 strain). Forty-eight hours after treatment and 48 h after each infestation, eggs were collected over a 3-h period, counted and viability determined. Dogs were combed to remove any remaining fleas.

Results: Treatment of dogs with oral fluralaner provided a 100 % reduction in flea counts 48 h after treatment and within 48 h of every post-treatment infestation through Day122. Egg production from fluralaner treated dogs was reduced by 99.9 % (two eggs from one dog) within 48 h after treatment and not a single egg (100 % efficacy) was thereafter collected from treated dogs. Adult flea counts and egg production from the fluralaner-treated dogs were significantly lower than for non-treated controls at all post-treatment evaluations (P < 0.001). The two eggs collected from the single treated dog 48 h after treatment did not produce any adult fleas. As no additional eggs were collected from treated dogs, no viability assessment was performed.

Conclusions: A single oral dose of fluralaner flavored chews provided 100 % efficacy against repeated flea infestations on dogs for 4 months. Fluralaner reduced egg production of activity reproducing female fleas by 99.9 % and then killed every single female flea before any eggs could be produced following each subsequent re-infestation for the entire 122-day evaluation period.

Keywords: Flea, Ctenocephalides felis felis, Cat flea, Dogs, Fluralaner, Egg production, Adulticide activity, Contro

Abstract

Background: The novel isoxazoline molecule fluralaner provides 12 weeks activity against fleas and 8 to 12 weeks against tick infestations according to label claims.

Methods: This blinded, multi-center study in client-owned dogs evaluated the flea control provided by a single oral fluralaner treatment (25–56 mg/kg; Bravecto™, Merck Animal Health) compared to a control group administered three oral spinosad (30 – 60 mg/kg; Comfortis®, Elanco) treatments at 4-week intervals together with an amitraz collar (9%, Preventic®, Virbac). Households were randomized (3:1 ratio) to either fluralaner (224 dogs, 118 households) or control (70 dogs, 39 households). Within households, one primary dog with at least 10 live fleas at enrollment was randomly selected for whole body flea counts every 4 weeks through Week 12; all dogs were followed for safety until Week 12. Fluralaner dogs received two additional doses at Weeks 12 and 24 for further safety and palatability observations through Week 26.

Results: Geometric mean flea count reductions from baseline for the fluralaner group at Weeks 4, 8, and 12 were 99.7%, 99.8%, and 99.8%, respectively; and 96.1%, 99.5%, and 99.6% for the spinosad controls. Percentages of flea-free primary dogs at Weeks 4, 8, and 12 were 91.1%, 95.4%, and 95.3% for the fluralaner group; and 44.7%, 88.2%, and 84.4% for the controls; the differences were significant at Weeks 4 (P < 0.0001) and 12 (P = 0.0370). Improvements in veterinarian assessed flea allergy dermatitis (FAD) were observed in both groups. Fluralaner tablets were accepted free choice in over 90% of doses. The most common adverse event was vomiting, occurring in 7.1% of the fluralaner group and 14.3% of the controls. No treatment related serious adverse events were reported.

Conclusions: A single treatment of dogs with the palatable fluralaner flavored chewable tablet provides a safe and effective option for 12 weeks of flea control at least equivalent to that of 3 sequential treatments with spinosad tablets. Linked to the high level of flea control was a substantial alleviation of associated signs of FAD.

Keywords: Fluralaner, Fleas, Spinosad, Efficacy, Safety, Field study

Abstract

Background: Fluralaner, a novel isoxazoline, has both acaricidal and insecticidal activity through potent blockage of GABA- and L-glutamate-gated chloride channels. This study investigated the in vitro and in vivo effects of fluralaner exposure on flea (Ctenocephalides felis) reproduction.

Methods: Blood spiked with sub-insecticidal fluralaner concentrations (between 0.09 and 50.0 ng/mL) was fed to fleas for 10 days using a membrane system. Cessation of reproduction in exposed fleas was assessed using flea survival, egg hatchability, and control of oviposition, pupae, and flea emergence. Fluralaner efficacy for in vivo Ctenocephalides (C.) felis control on dogs was assessed using a simulated flea-infested home environment. During a pre-treatment period, dogs were infested twice on days −28 and −21 with 100 adult unfed fleas to establish a thriving population by day 0 of the study. On day 0, one group of dogs was treated with fluralaner (Bravecto™; n = 10), while another group served as negative control (n = 10). Following treatment, dogs were infested three times with 50 fleas on days 22, 50 and 78 to simulate new infestations. Live flea counts were conducted weekly on all dogs for 12 weeks starting 1 day before treatment.

Results: Fluralaner potently inhibited flea reproduction capacity in vitro. Oviposition ceased completely at concentrations as low as 25.0 ng/mL. While no ovicidal effect was observed, fluralaner exerted a larvicidal effect at exceptionally low concentrations (6.25 ng/mL). In the simulated flea-infested home environment, flea-control efficacy on fluralaner-treated dogs was >99% at every time point measured for 12 weeks. No adverse events were observed in fluralaner-treated dogs.

Conclusions: Fluralaner completely controls egg laying, larval development and flea reproduction even at subinsecticidal concentrations. Oral treatment of dogs with fluralaner is highly effective for eliminating fleas in a simulated flea-infested home environment.

Keywords: Ctenocephalides felis, Fluralaner, Flea efficacy, Insecticidal, Reproduction, Dog, Simulated home environment

Abstract

Background: Fluralaner (Bravecto™) is a novel systemic insecticide and acaricide that provides long persistent antiparasitic activity following a single administration at the minimum dose of 25 mg/kg body weight.

Methods: Three negative controlled, randomized studies were conducted in dogs to evaluate the start to kill (1 study) and the speed of flea kill (2 studies) of fluralaner. All dogs were infested prior to treatment with unfed adult C. felis fleas. Dogs in the treated groups were administered once orally with fluralaner at a minimum dose of 25 mg/kg body weight, while dogs in the control groups were not treated. Separate control and treatment groups were paired at each time point of flea assessment. Flea counts were performed by combing dogs at either 0.5, 1, 2, or 4 hours after fluralaner treatment to measure the start to kill. To evaluate the speed of flea kill over 12 weeks, flea counts were performed by combing dogs at either 4, 8, 12, or 24 hours after fluralaner treatment and then at 4, 8, 12, or 24 hours after each flea re-infestations performed at 4, 8, and 12 weeks following treatment.

Results: In the start to kill study, the fluralaner activity against fleas started already at 1 hour post-treatment (8% numerical efficacy). At 2 and 4 hours post-treatment, the flea reduction was significant with 36.7% and 88% efficacy, respectively. In the speed of kill studies, the efficacy against fleas after fluralaner treatment was 80.5% at 4 hours and remained ≥ 99.4% at 8, 12 and 24 hours. After flea re-infestations in weeks 4, 8 and 12, the efficacy at 4 hours was 96.8, 91.4, and 33.5%, respectively. Efficacy at 8, 12 and 24 hours after flea re-infestations was 98.0-100% for the 12 weeks of the study. Except for 4 hours after the 12-week flea re-infestation, flea reduction was significant for all time points after flea re-infestation.

Conclusions: Single oral fluralaner administration rapidly eliminates existing flea infestations and provides excellent protection against fleas over 12 weeks following treatment.

Keywords: Bravecto™, Chewable tablets, Fluralaner, Onset of activity, Start to kill, Speed of kill, Dog, Flea, Ctenocephalides felis, Efficacy

Abstract

Background: A study was conducted to evaluate and compare the effectiveness of two different oral flea and tick products to control flea infestations, reduce pruritus and minimize dermatologic lesions over a 12 week period on naturally infested dogs in west central FL USA.

Methods: Thirty-four dogs with natural flea infestations living in 17 homes were treated once with a fluralaner chew on study day 0. Another 27 dogs living in 17 different homes were treated orally with an afoxolaner chewable on day 0, once between days 28–30 and once again between days 54–60. All products were administered according to label directions by study investigators. Flea populations on pets were assessed using visual area counts and premise flea infestations were assessed using intermittent-light flea traps on days 0, 7, 14, 21, and once between days 28–30, 40–45, 54–60 and 82–86. Dermatologic assessments were conducted on day 0 and once monthly. Pruritus assessments were conducted by owners throughout the study. No concurrent treatments for existing skin disease (antibiotics, anti-inflammatories, anti-fungals) were allowed.

Results: Following the first administration of fluralaner or afoxolaner, flea populations on pets were reduced by 99.0 % and 99.3 %, respectively within 7 days. Flea populations on the fluralaner treated dogs were 0 (100 % efficacy) on days 54–60 and 82–86 after the administration of a single dose on day 0. Administration of 3 monthly doses of afoxolaner reduced flea populations by 100 % on days 82–86. Flea numbers in indoor-premises were markedly reduced in both treatment groups by days 82–86, with 100 % and 98.9 % reductions in flea trap counts in the fluralaner and afoxolaner treatment groups, respectively. Marked improvement was observed in FAD lesion scoring, Atopic Dermatitis lesions scoring (CADESI-4) and pruritus scores with both formulations.

Conclusions: In a clinical field investigation conducted during the summer of 2015 in subtropical Florida, a single administration of an oral fluralaner chew completely eliminated dog and premises flea infestations and markedly reduced dermatology lesions and pruritus. Three monthly doses of the afoxolaner chewable also eliminated flea infestations in dogs, markedly reduced premises’ flea populations and similarly improved dermatology lesions and pruritus.

Keywords: Ctenocephalides felis felis, Cat flea, Dogs, Field study, Fluralaner, Flea, Flea control, Afoxolaner, Flea Allergy Dermatitis, Flea Bite Dermatitis, Pruritus, Atopic Dermatitis

Abstract

Background: Adherence to a prescribed therapeutic regimen is a critical factor for achieving medication effectiveness and therefore treatment success. In the case of companion animal ectoparasite control, suboptimal owner adherence to medication recommendations is thought to be a common cause of treatment failure, and previous reports have found pet owners applying an average of 4.0–4.6 monthly flea and tick treatments per year to their dogs. This study investigated: US veterinary hospital self-reported flea and tick prevention recommendations; dog owner recollection of these recommendations; dog owner opinion on flea/tick recommendations and estimated owner flea and tick medication adherence based on veterinary hospital purchase records.

Results: Veterinarians at 24 veterinary hospitals in 4 United States regions provided their flea and tick prevention recommendations. Five hundred fifty-nine dog owners, clients of the 24 hospitals, completed a survey evaluating their recollection of the hospitals’ recommendations and their opinions regarding required treatment frequency. Almost all veterinary hospitals in this study recommended 12 months of flea and tick prevention but only 62% of participating dog owners recalled this recommendation. The average owner response was that their dogs require 10.5 months of flea and tick prevention annually. Owner opinions were significantly different among U.S. regions with pet owners in the northeast U.S. believing that they needed significantly less canine flea and tick protection than pet owners in other parts of the United States. The estimated actual flea and tick prevention coverage was 6.1 months based on owner medication purchases over a 12-month period.

Conclusions: In the United States, dog owner opinions and actions show that their flea and tick treatment adherence falls short of veterinarians' recommendations.

Keywords: Compliance, Adherence, Flea, Tick, Dog, Fluralaner, Ectoparasites

Abstract

Background: Fluralaner is a potent acaricide and insecticide effective against flea and tick (F/T) infestations on dogs and cats. Fluralaner for dogs can be administered orally as a flavored chew with up to a 12-week redosing interval, about three-fold less frequently than monthly F/T medications. This study surveyed dog owners who currently administer fluralaner to their dogs to determine their level of satisfaction with the product and its perceived benefits compared to monthly medications, including the potential for on-time administration compliance.

Methods: In the period April to June 2016, dog-owner clients from 25 veterinary practices in 16 U.S. states completed a 10-item survey questionnaire (n=559) that asked respondents about their experience with fluralaner and monthly medications. In multivariate analyses, predictors of treatment satisfaction and predictors of preference with fluralaner have been estimated by an ordered logistic regression and a logistic regression, respectively.

Results: Seventy-three percent of survey respondents had used monthly F/T medications prior to fluralaner. Respondents identified convenience (74%), the 12-week dosing interval (69%), and less-frequent dosing (68%) as the three most important benefits of using fluralaner. Sixty six percent were very satisfied and 30% were satisfied with fluralaner and 89% preferred fluralaner versus monthly F/T medications. Pet owners who used monthly F/T products, 65% thought that they were more likely to give the next fluralaner dose on time compared to doses of monthly F/T products, and 88% said that giving repeat doses of fluralaner was more convenient than giving monthly F/T products. In multivariable models, "12 weeks dosing/convenience" and "female gender" were positively associated with treatment satisfaction and preference with fluralaner (p<0.05).

Conclusions: In the United States, dog owner opinions and actions show that their flea and tick treatment adherence falls short of veterinarians' recommendations.

Keywords: Overall satisfaction with fluralaner and preference for fluralaner compared to monthly F/T medications were high. The most significant

Abstract

Background: Fluralaner is a new antiparasitic drug that was recently introduced as Bravecto™ chewable tablets for the treatment of tick and flea infestations in dogs. Most marketed tick products exert their effect via topical application and contact exposure to the parasite. In contrast, Bravecto™ delivers its acaricidal activity through systemic exposure. Tick exposure to fluralaner occurs after attachment to orally treated dogs, which induces a tick-killing effect within 12 h. The fast onset of killing lasts over the entire treatment interval (12 weeks) and suggests that only marginal uptake by ticks is required to induce efficacy. Three laboratory studies were conducted to quantify the extent of uptake by comparison of ticks’ weight and coxal index obtained from Bravecto™-treated and negative-control dogs.

Methods: Three studies were conducted using experimental tick infestation with either Ixodes ricinus or Ixodes scapularis after oral administration of fluralaner to dogs. All studies included a treated (Bravecto™ chewable tablets, MSD Animal Health) and a negative control group. Each study had a similar design for assessing vitality and weighing of ticks collected from dogs of both groups. Additionally, in one study the coxal index (I. ricinus) was calculated as a ratio of tick’s ventral coxal gap and dorsal width of scutum. Tick weight data and coxal indices from Bravecto™-treated and negative-control groups were compared via statistical analysis.

Results: Ticks collected from Bravecto™-treated dogs weighed significantly less (p ≤ 0.0108) than ticks collected from negative-control dogs, and their coxal index was also significantly lower (p < 0.0001). The difference in tick weights was demonstrated irrespective of the tick species investigated (I. ricinus, I. scapularis). At some assessments the mean tick weights of Bravecto™-treated dogs were significantly lower than those of unfed pre-infestation (baseline) ticks. The demonstrated tick-killing efficacy was in the range of 94.6 – 100 %.

Conclusions: Tick weights and coxal indices confirm that a minimal uptake results in a sufficient exposure of ticks to fluralaner (Bravecto™) and consequently in a potent acaricidal effect.

Keywords: Bravecto™ chewable tablets, Fluralaner, Dog, Tick weight, Coxal index, Ixodes ricinus, Ixodes scapularis, Efficacy

Abstract

Background: The preventive effect of fluralaner chewable tablets (Bravecto™) against transmission of Babesia canis by Dermacentor reticulatus ticks was evaluated.

Methods: Sixteen dogs, tested negative for B. canis by PCR and IFAT, were allocated to two study groups. On day 0, dogs in one group (n = 8) were treated once orally with a fluralaner chewable tablet according to label recommendations and dogs in the control group (n = 8) remained untreated. On days 2, 28, 56, 70 and 84, dogs were infested with 50 (±4) B. canis infected D. reticulatus ticks with tick in situ thumb counts 48 ± 4 h post-infestation. Prior to each infestation, the D. reticulatus ticks were confirmed to harbour B. canis by PCR analysis. On day 90, ticks were counted and removed from all dogs. Efficacy against ticks was calculated for each assessment time point. After treatment, all dogs were physically examined in conjunction with blood collection for PCR every 7 days, blood samples for IFAT were collected every 14 days and the dog’s rectal body temperature was measured thrice weekly. From dogs displaying symptoms of babesiosis or were PCR positive, a blood smear was taken, and, if positive, dogs were rescue treated and replaced with a replacement dog. The preventive effect was evaluated by comparing infected dogs in the treated group with infected dogs in the untreated control group.

Results: All control dogs became infected with B. canis, as confirmed by PCR and IFAT. None of the 8 treated dogs became infected with B. canis, as IFAT and PCR were negative throughout the study until day 112. Fluralaner chewable tablet was 100 % effective against ticks on days 4, 30, 58, and 90 and an efficacy of 99.6 % and 99.2 % was achieved on day 72 and day 86 after treatment, respectively. Over the 12-week study duration, a 100 % preventive effect against B. canis transmission was demonstrated.

Conclusions: A single oral administration of fluralaner chewable tablets effectively prevented the transmission of B. canis by infected D. reticulatus ticks over a 12-week period.

Keywords: Bravecto™, Babesia canis, Babesiosis, Chewable tablets, Fluralaner, Dermacentor reticulatus, Dog, Efficacy, Preventive effect, Tick, Tick-borne disease, Transmission blocking

Abstract

Background: Ixodes holocyclus ticks are a frequently fatal threat to dogs in eastern Australia. These ticks secrete a neurotoxin that can produce an ascending paralysis after 72 h attachment that can lead to death in affected animals. Fluralaner is a potent systemic acaricide with immediate and persistent efficacy for tick control including evidence of 100% efficacy against Ixodes ricinus ticks within 72 h. This study investigated the potential for oral fluralaner administration to control I. holocyclus infestation and the subsequent risk of host paralysis.

Methods: Healthy Foxhound and Foxhound cross dogs immunized against holocyclotoxin were randomly allocated to receive either a single fluralaner (at least 25 mg/kg) dose or no treatment. All dogs were penned individually and infested with 30 adult unfed female I. holocyclus 1 day before treatment and 14, 28, 42, 56, 70, 84, 112 and 140 days following treatment. Ticks were counted and assessed at 24, 48 and 72 h after the initial fluralaner treatment and after each subsequent infestation. Ticks were not removed at the 24 and 48 h assessments, but were removed after the 72 h assessments. On 112 and 140 days post treatment a new group of untreated control dogs was used.

Results: Fluralaner treatment efficacy against I. holocyclus was 100% at 72 h post treatment. Following re-infestations the efficacy remained at 100% at the 72 h assessments for 115 days and reached 95.7% at 143 days. The differences between mean live tick counts on treatment and control groups were significant (P < 0.00l) at all assessment time points for 143 days following treatment.

Conclusions: Oral fluralaner treatment can prevent Australian paralysis tick infestations for at least 115 days.

Keywords: Dog, Fluralaner, Tick, Paralysis, Australia, Ixodes holocyclus

Abstract

Background: Fluralaner is a novel isoxazoline eliciting both acaricidal and insecticidal activity through potent blockage of GABA- and glutamate-gated chloride channels. The aim of the study was to investigate the susceptibility of juvenile stages of common tick species exposed to fluralaner through either contact (Rhipicephalus sanguineus) or contact and feeding routes (Ornithodoros moubata).

Methods: Fluralaner acaricidal activity through both contact and feeding exposure was measured in vitro using two separate testing protocols. Acaricidal contact activity against Rhipicephalus sanguineus life stages was assessed using three minute immersion in fluralaner concentrations between 50 and 0.05 μg/mL (larvae) or between 1000 and 0.2 μg/mL (nymphs and adults). Contact and feeding activity against Ornithodoros moubata nymphs was assessed using fluralaner concentrations between 1000 to 10−4 μg/mL (contact test) and 0.1 to 10−10 μg/mL (feeding test). Activity was assessed 48 hours after exposure and all tests included vehicle and untreated negative control groups.

Results: Fluralaner lethal concentrations (LC₅₀, LC_90/95) were defined as concentrations with either 50%, 90% or 95% killing effect in the tested sample population. After contact exposure of R. sanguineus life stages lethal concentrations were (μg/mL): larvae - LC₅₀ 0.7, LC₉₀ 2.4; nymphs - LC₅₀ 1.4, LC₉₀ 2.6; and adults - LC₅₀ 278, LC₉₀ 1973. After exposure of O. moubata nymphs to fluralaner lethal concentrations were (μg/mL): contact exposure - LC₅₀ 720, LC₉₅ 1133; and feeding exposure- LC₅₀ 0.00007, LC95 0.09.

Conclusions: Fluralaner demonstrates potent in vitro acaricidal activity against all life stages of the brown dog tick, R.sanguineus. The testing of fluralaner contact and feeding routes using O. moubata nymphs demonstrates a high acaricidal activity in both exposure routes.

Keywords: Rhipicephalus sanguineus, Ornithodoros moubata, Fluralaner, Acaricidal activity, Tick life stages

Abstract

Background: Pathogens that are transmitted by ticks to dogs, such as Anaplasma phagocytophilum, Babesia spp., Borrelia burgdorferi sensu latu, and Ehrlichia canis, are an increasing problem in the world. One method to prevent pathogen transmission to dogs is to kill the ticks before transmission occurs. Fluralaner (Bravecto™) is a novel isoxazoline insecticide and acaricide that provides long persistent antiparasitic activity following systemic administration. This study investigated the speed of kill of fluralaner against Ixodes ricinus ticks on dogs.

Methods: A total of 48 dogs were randomized to 8 groups of 6 dogs and each dog was infested with 50 female and 10 male I. ricinus ticks. Two days later (day 0), 4 groups received a single treatment of 25 mg fluralaner/kg body weight as Bravecto™ chewable tablets; the dogs in the other 4 groups were left untreated. Separate control and treatment groups were paired at each time point (4, 8, 12, or 24 hours after treatment) for assessment of tick-killing efficacy. At 4, 8, and 12 weeks after treatment, all dogs were re-infested with 50 female I. ricinus ticks and subsequently assessed for live or dead ticks at either 4, 8, 12, or 24 hours after re-infestation. Efficacy was calculated for each assessment time point by comparison of the treatment group with the respective control group.

Results: Tick-killing efficacy was 89.6% at 4 hours, 97.9% at 8 hours, and 100% at 12 and 24 hours after treatment. Eight hours after re-infestation, efficacy was 96.8%, 83.5%, and 45.8% at 4, 8, and 12 weeks after treatment, respectively. At least 98.1% tick-killing efficacy was demonstrated 12 and 24 hours after re-infestation over the entire 12 week study period.

Conclusions: Fluralaner kills ticks rapidly after treatment at 4 hours, and over its entire 12-week period of efficacy, it achieves an almost complete killing effect within 12 hours after tick infestation. The rapid tick-killing effect together with the long duration of efficacy enables fluralaner to aid in the prevention of tick borne diseases.

Keywords: Bravecto™ chewable tablets, Fluralaner, Speed of kill, Dog, Tick, Ixodes ricinus, Tick-borne diseases, Efficacy

Abstract

Background: Adherence to a prescribed therapeutic regimen is a critical factor for achieving medication effectiveness and therefore treatment success. In the case of companion animal ectoparasite control, suboptimal owner adherence to medication recommendations is thought to be a common cause of treatment failure, and previous reports have found pet owners applying an average of 4.0–4.6 monthly flea and tick treatments per year to their dogs. This study investigated: US veterinary hospital self-reported flea and tick prevention recommendations; dog owner recollection of these recommendations; dog owner opinion on flea/tick recommendations and estimated owner flea and tick medication adherence based on veterinary hospital purchase records.

Results: Veterinarians at 24 veterinary hospitals in 4 United States regions provided their flea and tick prevention recommendations. Five hundred fifty-nine dog owners, clients of the 24 hospitals, completed a survey evaluating their recollection of the hospitals’ recommendations and their opinions regarding required treatment frequency. Almost all veterinary hospitals in this study recommended 12 months of flea and tick prevention but only 62% of participating dog owners recalled this recommendation. The average owner response was that their dogs require 10.5 months of flea and tick prevention annually. Owner opinions were significantly different among U.S. regions with pet owners in the northeast U.S. believing that they needed significantly less canine flea and tick protection than pet owners in other parts of the United States. The estimated actual flea and tick prevention coverage was 6.1 months based on owner medication purchases over a 12-month period.

Conclusions: In the United States, dog owner opinions and actions show that their flea and tick treatment adherence falls short of veterinarians' recommendations.

Keywords: Compliance, Adherence, Flea, Tick, Dog, Fluralaner, Ectoparasites

Abstract

Background: Fluralaner is a potent acaricide and insecticide effective against flea and tick (F/T) infestations on dogs and cats. Fluralaner for dogs can be administered orally as a flavored chew with up to a 12-week redosing interval, about three-fold less frequently than monthly F/T medications. This study surveyed dog owners who currently administer fluralaner to their dogs to determine their level of satisfaction with the product and its perceived benefits compared to monthly medications, including the potential for on-time administration compliance.

Methods: In the period April to June 2016, dog-owner clients from 25 veterinary practices in 16 U.S. states completed a 10-item survey questionnaire (n=559) that asked respondents about their experience with fluralaner and monthly medications. In multivariate analyses, predictors of treatment satisfaction and predictors of preference with fluralaner have been estimated by an ordered logistic regression and a logistic regression, respectively.

Results: Seventy-three percent of survey respondents had used monthly F/T medications prior to fluralaner. Respondents identified convenience (74%), the 12-week dosing interval (69%), and less-frequent dosing (68%) as the three most important benefits of using fluralaner. Sixty six percent were very satisfied and 30% were satisfied with fluralaner and 89% preferred fluralaner versus monthly F/T medications. Pet owners who used monthly F/T products, 65% thought that they were more likely to give the next fluralaner dose on time compared to doses of monthly F/T products, and 88% said that giving repeat doses of fluralaner was more convenient than giving monthly F/T products. In multivariable models, "12 weeks dosing/convenience" and "female gender" were positively associated with treatment satisfaction and preference with fluralaner (p<0.05).

Conclusions: In the United States, dog owner opinions and actions show that their flea and tick treatment adherence falls short of veterinarians' recommendations.

Keywords: Overall satisfaction with fluralaner and preference for fluralaner compared to monthly F/T medications were high. The most significant

Abstract

Background: Fluralaner (Bravecto™; Merck/MSD Animal Health) is a novel systemic ectoparasiticide for dogs providing long-acting flea and tick control after a single oral dose. Milbemycin oxime and praziquantel are routinely used to control Dirofilaria immitis and intestinal worm infections in dogs. The safety of concurrent use of fluralaner and a commercially available milbemycin oxime plus praziquantel combination tablet, in particular with regard to gastrointestinal symptoms, was investigated using oral doses at or above the maximum recommended rates.

Findings: Some minor and transient clinical findings were observed during the study period; however, none of these was considered to be related to concurrent treatment with fluralaner and milbemycin oxime plus praziquantel, or to the use of either product alone.

Conclusions: Concurrent treatment with fluralaner, milbemycin oxime and praziquantel is well tolerated in dogs.

Keywords: Bravecto™, Fluralaner, Dog, Safety, Milbemycin oxime, Praziquante

Abstract

Background: Bravecto™ (fluralaner; MSD Animal Health) is a novel systemic ectoparasiticide for dogs providing long-acting flea- and tick-control after a single oral dose. Scalibor™ Protectorband (deltamethrin; MSD Animal Health) is a collar often used to reduce sandfly feeding for leishmaniasis prevention. This study investigated the safety of the concurrent use of Bravecto™ and Scalibor™ Protectorband at the recommended dosage regimens.

Findings: Throughout the study period of 24 weeks, there were no clinical findings related to the concurrent treatment with Bravecto™ in dogs fitted with Scalibor Protectorband at the recommended dosage regimens.

Conclusions: Concurrent treatment with Bravecto™ in dogs fitted with Scalibor™ Protectorband is well tolerated.

Keywords: Bravecto™, Fluralaner, Dog, Safety, Scalibor™, Deltamethrin

Abstract

Background: Fluralaner is a novel systemic insecticide and acaricide that provides long acting efficacy in dogs after a single oral treatment. This study investigated the safety of oral administration of fluralaner in chewable tablets to dogs at the highest recommended treatment dose and at multiples of this dose.

Methods: Thirty-two (16 male and 16 female) healthy 8-week old Beagle dogs weighing 2.0 - 3.6 kg at first administration were included in the study. Fluralaner was administered on three occasions at 8-week intervals at doses of up to 56, 168, and 280 mg fluralaner/kg body weight, equivalent to 1, 3, and 5 times the highest recommended treatment dose of fluralaner; sham dosed dogs served as controls.

During the study, all dogs were clinically observed, and their health was carefully monitored including body weight development, food consumption and measurement of hematology, coagulation, clinical chemistry (including measurement of levels of ACTH and C-reactive protein) and urinalysis. Following euthanasia of the dogs, complete gross post mortem examination, including organ weight determination, and histopathological examination of multiple tissues were conducted.

Results: There were no clinical findings related to fluralaner treatment. Statistically significant differences between the treated groups and the control group were observed for some clinical pathology parameters and organ weights; none of these findings were considered to be of clinical relevance.

Conclusions: Oral administration of fluralaner at the highest recommended treatment dose (56 mg/kg) at 8-week intervals is well tolerated and has a safety margin of more than five in healthy dogs eight weeks of age or older and weighing at least 2 kg.

Keywords: Fluralaner, Dog, Safety, Bravecto™

Abstract

Background: Fluralaner is a novel systemic ectoparasiticide for dogs providing long-acting flea- and tick-control after a single oral dose. This study investigated the safety of oral administration of fluralaner at 3 times the highest expected clinical dose to Multi Drug Resistance Protein 1 (MDR1(−/−)) gene defect Collies.

Methods: Sixteen Collies homozygous for the MDR1 deletion mutation were included in the study. Eight Collies received fluralaner chewable tablets once at a dose of 168 mg/kg; eight sham dosed Collies served as controls. All Collies were clinically observed until 28 days following treatment.

Results: No adverse events were observed subsequent to fluralaner treatment of MDR1(−/−) Collies at three times the highest expected clinical dose.

Conclusions: Fluralaner chewable tablets are well tolerated in MDR1(−/−) Collies following oral administration.

Keywords: Fluralaner, Bravecto™, Dog, Safety, MDR1

Abstract

Background: Fluralaner, a new molecular entity of the isoxazoline class, has potent insecticidal and acaricidal activity and can be safely administered orally to dogs.

Methods: A randomized, investigator-blinded, multi-centered field study compared the flea- and tick-control efficacy for dogs over a 12-week period with either a single oral dose of Bravecto™ (fluralaner) formulated as a chewable tablet or with three sequential topical Frontline™ (fipronil) treatments. Individual dogs were the experimental unit for ticks and households were the experimental unit for fleas. A total of 108 tick-infested dogs were treated with Bravecto™ (fluralaner) and 54 tick-infested dogs were treated with Frontline™ (fipronil). Dogs in 115 flea-infested households received Bravecto™ (fluralaner) and dogs in 61 flea-infested households received Frontline™ (fipronil). Flea and tick counts were conducted on all dogs at weeks 2, 4, 8, and 12 following initial treatment and efficacy was calculated as the mean percent reduction in tick or flea count at each time point compared with the mean pretreatment initiation count for each treatment group. Additionally, the percentages of tick-free and flea-free households were determined.

Results: At weeks 2, 4, 8, and 12, Bravecto™ (fluralaner) flea-control efficacy in treated households was 99.2%, 99.8%, 99.8%, and 99.9% respectively, while Frontline™ (fipronil) efficacy was 94.1%, 93.0%, 96.0%, and 97.3%, respectively. Bravecto™ (fluralaner) tick-control efficacy on treated dogs at weeks 2, 4, 8, and 12 was 99.9%, 99.9%, 99.7%, and 100%, respectively, and Frontline™ (fipronil) tick efficacy was 97.6%, 93.8%, 100%, and 100%, respectively. Of dogs showing clinical flea allergy dermatitis (FAD) signs at the study start, 85.7% in the Bravecto™ (fluralaner)-treated group and 55.6% in the Frontline™ (fipronil)-treated group were evaluated at each time point as showing no clinical signs of FAD until study completion.

Conclusions: Bravecto™ (fluralaner) administered once orally to dogs in a chewable tablet was highly effective for 12 weeks against fleas and ticks on privately-owned dogs and was significantly non-inferior (ticks) and superior (fleas) in comparison with topical Frontline™ (fipronil) administered 3 times sequentially.

Keywords: Fleas, Ticks, Bravecto™ (fluralaner), Isoxazoline, Frontline™ (fipronil), Efficacy, Field study, Dog

Abstract

Background: A study was conducted to evaluate and compare the effectiveness of two different oral flea and tick products to control flea infestations, reduce pruritus and minimize dermatologic lesions over a 12 week period on naturally infested dogs in west central FL USA.

Methods: Thirty-four dogs with natural flea infestations living in 17 homes were treated once with a fluralaner chew on study day 0. Another 27 dogs living in 17 different homes were treated orally with an afoxolaner chewable on day 0, once between days 28–30 and once again between days 54–60. All products were administered according to label directions by study investigators. Flea populations on pets were assessed using visual area counts and premise flea infestations were assessed using intermittent-light flea traps on days 0, 7, 14, 21, and once between days 28–30, 40–45, 54–60 and 82–86. Dermatologic assessments were conducted on day 0 and once monthly. Pruritus assessments were conducted by owners throughout the study. No concurrent treatments for existing skin disease (antibiotics, anti-inflammatories, anti-fungals) were allowed.

Results: Following the first administration of fluralaner or afoxolaner, flea populations on pets were reduced by 99.0 % and 99.3 %, respectively within 7 days. Flea populations on the fluralaner treated dogs were 0 (100 % efficacy) on days 54–60 and 82–86 after the administration of a single dose on day 0. Administration of 3 monthly doses of afoxolaner reduced flea populations by 100 % on days 82–86. Flea numbers in indoor-premises were markedly reduced in both treatment groups by days 82–86, with 100 % and 98.9 % reductions in flea trap counts in the fluralaner and afoxolaner treatment groups, respectively. Marked improvement was observed in FAD lesion scoring, Atopic Dermatitis lesions scoring (CADESI-4) and pruritus scores with both formulations.

Conclusions: In a clinical field investigation conducted during the summer of 2015 in subtropical Florida, a single administration of an oral fluralaner chew completely eliminated dog and premises flea infestations and markedly reduced dermatology lesions and pruritus. Three monthly doses of the afoxolaner chewable also eliminated flea infestations in dogs, markedly reduced premises’ flea populations and similarly improved dermatology lesions and pruritus.

Keywords: Ctenocephalides felis felis, Cat flea, Dogs, Field study, Fluralaner, Flea, Flea control, Afoxolaner, Flea Allergy Dermatitis, Flea Bite Dermatitis, Pruritus, Atopic Dermatitis