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Marsh AE, Lakritz J. Reflecting on the past and fast forwarding to present day anthelmintic resistant Ancylostoma caninum-A critical issue we neglected to forecast. Int J Parasitol Drugs Drug Resist 2023; 22:36-43. [PMID: 37229949 PMCID: PMC10229760 DOI: 10.1016/j.ijpddr.2023.04.003] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2022] [Revised: 04/28/2023] [Accepted: 04/29/2023] [Indexed: 05/27/2023]
Abstract
Reports of anthelmintic resistance in Ancylostoma caninum are increasing in frequency in the United States of America (USA). In the last few years in vitro and in vivo studies characterized individual isolates, demonstrating multiple anthelmintic drug resistance (MADR). In 2021, the American Association of Veterinary Parasitologists initiated a hookworm task force to address this issue. The first report of drug resistant A. caninum occurred in 1987 in Australian racing Greyhounds. In the last five years multiple case reports and investigations show drug resistant A. caninum is becoming a much greater problem in the USA and now extends beyond racing Greyhounds into the general companion animal dog population. The literature, regarding drug resistance in livestock and equine nematodes, provides helpful guidance along with diagnostic methods to better understand the evolution and selection of canine MADR hookworms; however, there are limitations and caveats due to A. caninum's unique biology and zoonotic potential. Mass drug administration (MDA) of anthelminthic drugs to humans to reduce morbidity associated with human hookworms (Necator americanus) should consider the factors that contributed to the development of MADR A. caninum. Finally, as Greyhound racing undergoes termination in some regions and the retired dogs undergo subsequent rehoming, drug resistant parasites, if present, are carried with them. Drug resistant A. caninum requires greater recognition by the veterinary community, and small animal practitioners need to be aware of the spread into current pet dog populations. The current understanding of anthelmintic resistance, available treatments, and environmental mitigation for these drug resistant A. caninum isolates must be monitored for horizontal spread. A major goal in this emerging problem is to prevent continued dissemination.
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Affiliation(s)
| | - Jeffrey Lakritz
- Veterinary Clinical Sciences, The Ohio State University, USA
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Vercelli C, Bertolotti L, Gelsi E, Gazza C, Re G. Evaluation of Side Effects and Long-Term Protection of a Sustained-Release Injectable Moxidectin Formulation against Dirofilaria immitis Infection in Dogs: An Observational—In Field Multicentric Study. Vet Sci 2022; 9:vetsci9080408. [PMID: 36006323 PMCID: PMC9415797 DOI: 10.3390/vetsci9080408] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2022] [Revised: 07/25/2022] [Accepted: 08/02/2022] [Indexed: 11/16/2022] Open
Abstract
Simple Summary The sustained-release moxidectin formulation of Afilaria SR is labelled to prevent Dirofilaria immitis infection in dogs for a period of six months. An observational—in field multicentric study was design to evaluate the tolerability and the long-term prevention of Afilaria SR in Italy. A total of 583 dogs were recruited from 2018 to 2021, receiving the drug annually and monitored by veterinary practitioners after each administration. Antigenic tests were performed 210, 365, 730, and 1095 days after the administration of the drug. None of the enrolled dogs was detected as positive, since it was possible to establish that 100% of protection was achieved. Afilaria SR was well tolerated since only the 13% of dogs demonstrated mild reaction in the injection site and only two dogs out of 583 demonstrated anaphylactoid or angioneurotic reactions. These data support the high prevention rate against Dirofilaria immitis disease in all enrolled dogs and indicate the high safety profile of the product, considering the low number and the low grade of side effects. Abstract The sustained-release moxidectin formulation Afilaria SR is a relatively new product and has been labelled to prevent Dirofilaria immitis infection in dogs for a six months-period. An observational, in field multicentric study was performed, aiming to evaluate the tolerability and the long-term prevention of Afilaria SR in Italy, a country where filariasis is endemic. The study was designed to include not less than 300 dogs, older than 6 months, of any breed. Side effects were recorded by veterinarians and antigenic tests were performed after 210, 365, 730, and 1095 days after the administration of the drug. A total of 583 dogs were recruited from 2018 to 2021 and all of them were negative with respect to antigenic tests at all time points, indicating that 100% of protection was achieved. Ranking of adverse reactions and correlation to patient features were analyzed using descriptive statistics and χ2 square test, respectively. Afilaria SR was well tolerated: 13% of dogs experienced mild reactions and only two dogs out of 583 (0.3%) demonstrated anaphylactoid/angioneurotic reactions, resolved administering corticosteroids. These data support that Afilaria SR prevented Dirofilaria immitis disease in all enrolled dogs and the low number and the low grade of side effects indicate the high safety profile of the product.
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Affiliation(s)
- Cristina Vercelli
- Department of Veterinary Science, University of Turin, Largo Paolo Braccini 2, 10095 Grugliasco, TO, Italy
- Correspondence: ; Tel.: +39-011-670-9710
| | - Luigi Bertolotti
- Department of Veterinary Science, University of Turin, Largo Paolo Braccini 2, 10095 Grugliasco, TO, Italy
| | - Elisa Gelsi
- Azienda Terapeutica Italiana A.T.I. s.r.l., Fatrogroup, Via Emilia, 285, 40064 Ozzano dell’Emilia, BO, Italy
| | - Carlo Gazza
- Azienda Terapeutica Italiana A.T.I. s.r.l., Fatrogroup, Via Emilia, 285, 40064 Ozzano dell’Emilia, BO, Italy
| | - Giovanni Re
- Department of Veterinary Science, University of Turin, Largo Paolo Braccini 2, 10095 Grugliasco, TO, Italy
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Savadelis MD, McTier TL, Kryda K, Maeder SJ, Woods DJ. Moxidectin: heartworm disease prevention in dogs in the face of emerging macrocyclic lactone resistance. Parasit Vectors 2022; 15:82. [PMID: 35277180 PMCID: PMC8915515 DOI: 10.1186/s13071-021-05104-7] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2020] [Accepted: 11/18/2021] [Indexed: 12/04/2022] Open
Abstract
Heartworm (Dirofilaria immitis) disease continues to increase and spread, remaining one of the most important and pathogenic parasitic diseases of dogs, despite the regular use of macrocyclic lactones (MLs) in preventive products. Dogs harboring strains of D. immitis resistant to MLs, the only drug class available for heartworm prevention in the United States, have been documented and proven. As no new products are available utilizing a novel drug class for the prevention of this disease, the only options for combating ML resistance include increasing the dose and/or changing the dosage regime of current MLs, or by optimizing the formulations of MLs currently available. Moxidectin provides a unique opportunity for optimization of the dose and formulation, which may provide improved efficacy against ML-resistant strains. Currently there are oral, topical, and injectable moxidectin products approved for heartworm prevention in the USA. Two new products (ProHeart® 12 and Simparica Trio®), available in many countries around the world including the USA, take advantage of the unique attributes of moxidectin for providing robust heartworm prevention against the strains of heartworm to which most dogs in the USA will likely be exposed. Both products have demonstrated 100% preventive efficacy in laboratory studies against recently collected field strains of heartworm, and also in large field studies, where the majority of dogs were living in the southern USA in areas where ML resistance has been confirmed to occur, therefore under elevated heartworm challenge. Based on the data summarized here, these products offer important advances in heartworm prevention and provide additional options for veterinarians and pet owners to protect their dogs from developing heartworm disease.
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McCrea AR, Edgerton EB, Oliver GT, O'Neill FM, Nolan TJ, Lok JB, Povelones M. A novel assay to isolate and quantify third-stage Dirofilaria immitis and Brugia malayi larvae emerging from individual Aedes aegypti. Parasit Vectors 2021; 14:30. [PMID: 33413579 PMCID: PMC7789620 DOI: 10.1186/s13071-020-04529-w] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2020] [Accepted: 12/07/2020] [Indexed: 11/11/2022] Open
Abstract
Background Mosquitoes transmit filarial nematodes to both human and animal hosts, with worldwide health and economic consequences. Transmission to a vertebrate host requires that ingested microfilariae develop into infective third-stage larvae capable of emerging from the mosquito proboscis onto the skin of the host during blood-feeding. Determining the number of microfilariae that successfully develop to infective third-stage larvae in the mosquito host is key to understanding parasite transmission potential and to developing new strategies to block these worms in their vector. Methods We developed a novel method to efficiently assess the number of infective third-stage filarial larvae that emerge from experimentally infected mosquitoes. Following infection, individual mosquitoes were placed in wells of a multi-well culture plate and warmed to 37 °C to stimulate parasite emergence. Aedes aegypti infected with Dirofilaria immitis were used to determine infection conditions and assay timing. The assay was also tested with Brugia malayi-infected Ae. aegypti. Results Approximately 30% of Ae. aegypti infected with D. immitis and 50% of those infected with B. malayi produced emerging third-stage larvae. Once D. immitis third-stage larvae emerged at 13 days post infection, the proportion of mosquitoes producing them and the number produced per mosquito remained stable until at least day 21. The prevalence and intensity of emerging third-stage B. malayi were similar on days 12–14 post infection. Increased uptake of D. immitis microfilariae increased the fitness cost to the mosquito but did not increase the number of emerging third-stage larvae. Conclusions We provide a new assay with an associated set of infection conditions that will facilitate assessment of the filarial transmission potential of mosquito vectors and promote preparation of uniformly infectious third-stage larvae for functional assays. The ability to quantify infection outcome will facilitate analyses of molecular interactions between vectors and filariae, ultimately allowing for the establishment of novel methods to block disease transmission. ![]()
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Affiliation(s)
- Abigail R McCrea
- Department of Pathobiology, School of Veterinary Medicine, University of Pennsylvania, Philadelphia, PA, 19104, USA
| | - Elizabeth B Edgerton
- Department of Pathobiology, School of Veterinary Medicine, University of Pennsylvania, Philadelphia, PA, 19104, USA
| | - Genevieve T Oliver
- Department of Pathobiology, School of Veterinary Medicine, University of Pennsylvania, Philadelphia, PA, 19104, USA
| | - Fiona M O'Neill
- Department of Pathobiology, School of Veterinary Medicine, University of Pennsylvania, Philadelphia, PA, 19104, USA
| | - Thomas J Nolan
- Department of Pathobiology, School of Veterinary Medicine, University of Pennsylvania, Philadelphia, PA, 19104, USA
| | - James B Lok
- Department of Pathobiology, School of Veterinary Medicine, University of Pennsylvania, Philadelphia, PA, 19104, USA
| | - Michael Povelones
- Department of Pathobiology, School of Veterinary Medicine, University of Pennsylvania, Philadelphia, PA, 19104, USA.
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Muñoz AAF, Martinez AR, Pinilla JC. Prevalence of Dirofilaria immitis in shelter dogs in Bucaramanga metropolitan area, Colombia. VETERINARY PARASITOLOGY- REGIONAL STUDIES AND REPORTS 2020; 22:100489. [PMID: 33308715 DOI: 10.1016/j.vprsr.2020.100489] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/23/2020] [Revised: 10/23/2020] [Accepted: 10/30/2020] [Indexed: 11/25/2022]
Abstract
The heartworm Dirofilaria immitis is the causative agent of cardiopulmonary dirofilariosis in dogs and cats and also infects humans. The current knowledge about this parasite in South America is scarce compared to North America and Europe. Nevertheless, this parasite has been reported in some regions of Colombia. The objective of this study was to determine the prevalence and risk factors associated with D. immitis infection in shelter dogs from Bucaramanga metropolitan area. We performed a cross-sectional study using blood samples from shelter dogs. Microfilariae testing of whole blood included a blood smear and modified Knott's test. Antigen testing of serum was performed using the Anigen Rapid HW Ag Test Kit 2.0 ®. A descriptive analysis and univariable logistic regression analysis were applied. A total of 207 whole blood samples, from 7 shelters dogs in the Bucaramanga metropolitan area, were utilized. The overall prevalence of D. immitis observed in shelter dogs in the Bucaramanga metropolitan area by blood smears and modified Knott's test was 6.3% (13/ 207) and 0.5% (1/207) by immunochromatography test kit. Regarding the prevalence by municipalities, there was a statistical association (P < .05), indicating that the prevalence was higher in dogs in Girón municipality. Likewise, there was a statistical association (P < .05) between the prevalence with respect to heartworm knowledge and mosquito control. For prevalence by gender, age group, dog breed, and hair length, there was no statistical association (P > .05). For Girón municipality there was a 7.1 times (OR = 7.1; CI95% 0.8-59.2; P < .05) increased infection risk. This study provides current data and the first known report of the prevalence of D. immitis microfilaremia and antigenemia in shelter dogs in the Bucaramanga metropolitan area, and these results could be useful for designing new control measures for this infection. We observed that the prevalence of both microfilaremia and antigenemia was significantly lower in these sampled dogs compared to previous reports.
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Affiliation(s)
- Angel Alberto Florez Muñoz
- Facultad de Ciencias Exactas, Naturales y Agropecuarias, Universidad de Santander, Grupo de Investigación en Ciencias Agropecuarias-GICA, Campus lagos del Cacique, CP 680006 Bucaramanga, Colombia.
| | - Ariel Rosas Martinez
- Escuela Medicina Veterinaria y Zootecnia, Instituto Universitario de la Paz, Barrancabermeja CP 687037, Colombia.
| | - Juan Carlos Pinilla
- Facultad de Ciencias Exactas, Naturales y Agropecuarias, Universidad de Santander, Grupo de Investigación en Ciencias Agropecuarias-GICA, Campus lagos del Cacique, CP 680006 Bucaramanga, Colombia.
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Alberigi B, Fernandes JI, Paiva JP, Mendes-de-Almeida F, Knackfuss F, Merlo A, Labarthe N. Efficacy of semi-annual therapy of an extended-release injectable moxidectin suspension and oral doxycycline in Dirofilaria immitis naturally infected dogs. Parasit Vectors 2020; 13:503. [PMID: 33023664 PMCID: PMC7539499 DOI: 10.1186/s13071-020-04380-z] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2020] [Accepted: 09/24/2020] [Indexed: 11/21/2022] Open
Abstract
Background Dirofilaria immitis is a life-threatening nematode spreading globally. Arsenical treatment is currently recommended for removal of adult worms. However, arsenical treatment is not available in some countries, and there are dogs that cannot tolerate the rapid kill of adult worms; therefore, alternative adulticide slow-kill treatments are needed. Criticisms against the use of these alternative protocols include the potential for allowing disease to progress and for the development of ML-resistant worms. Methods The efficacy of a protocol that includes semi-annual doses (i.e. every 6 months) of commercially available extended-release injectable moxidectin suspension (ProHeart® SR-12) with 30-day oral administration of doxycycline was studied in 20 dogs with naturally occurring D. immitis infections. Each dog received treatment with ProHeart® SR-12 (0.5 mg moxidectin/kg) by subcutaneous injection and oral doxycycline (10 mg/kg/bid × 30 days) every 6 months until two consecutive negative antigen test results were obtained. Pulmonary and cardiac evaluations were performed by radiographic and echocardiographic parameters. Physical examinations, complete blood counts, clinical chemistry profiles, microfilariae and antigen tests were performed periodically. Results At enrollment, all dogs were positive for D. immitis antigen and 18 were microfilaremic. On day 30, microfilaremia counts decreased, and all dogs became amicrofilaremic by day 150. On day 180, 11 dogs were antigen-negative, and 7 more became negative by day 360. The two remaining antigen-positive dogs converted to negative by day 540 or 810. All antigen tests performed 180 days after the first negative test were negative. There was no decline in cardiac performance of the dogs throughout the study. Overall, pulmonary clinical conditions, presence of worms by echocardiography, and enlargement of caudal and main pulmonary arteries improved after treatment. Physical examinations, complete blood count results, and clinical chemistry profiles were within normal reference values. Respiratory conditions were improved, no damage to the heart was observed, and the treatment protocol was well tolerated by the animals. Conclusions This alternative adulticide treatment was efficacious and well tolerated in naturally infected dogs. The injectable formulation provides the advantage of having veterinarians able to administer, monitor, and assess the efficacy and condition of the dog throughout the treatment and post-treatment periods.![]()
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Affiliation(s)
- Bruno Alberigi
- Programa de Pós-Graduação em Medicina Veterinária, Universidade Federal Rural do Rio de Janeiro, Rio de Janeiro, Brazil.
| | - Julio I Fernandes
- Departamento de Medicina e Cirurgia Veterinária, Instituto de Veterinária, Universidade Federal Rural do Rio de Janeiro, Rio de Janeiro, Brazil
| | - Jonimar P Paiva
- Departamento de Medicina e Cirurgia Veterinária, Instituto de Veterinária, Universidade Federal Rural do Rio de Janeiro, Rio de Janeiro, Brazil
| | - Flavya Mendes-de-Almeida
- Departamento de Patologia e Clínica Veterinária, Universidade Federal Fluminense - UFF, Niterói, RJ, Brazil
| | - Fabiana Knackfuss
- Universidade do Grande Rio - UNIGRANRIO, Duque de Caxias, RJ, Brazil
| | - Alexandre Merlo
- Technical Services for Companion Animals, Zoetis, São Paulo, Brazil
| | - Norma Labarthe
- Programa de Pós-Graduação em Bioética, Ética Aplicada e Saúde Coletiva. Escola Nacional de Saúde Pública, Fundação Oswaldo Cruz, Rio de Janeiro, Brazil
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McTier TL, Six RH, Pullins A, Chapin S, Kryda K, Mahabir SP, Woods DJ, Maeder SJ. Preventive efficacy of oral moxidectin at various doses and dosage regimens against macrocyclic lactone-resistant heartworm (Dirofilaria immitis) strains in dogs. Parasit Vectors 2019; 12:444. [PMID: 31506088 PMCID: PMC6737633 DOI: 10.1186/s13071-019-3685-3] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2019] [Accepted: 08/23/2019] [Indexed: 11/14/2022] Open
Abstract
Background Moxidectin has previously shown limited efficacy (≤ 44.4%) against confirmed macrocyclic lactone (ML)-resistant Dirofilaria immitis strains at 3 µg/kg after single and multiple oral dosages. Three studies were conducted to evaluate higher oral moxidectin doses for efficacy against confirmed ML-resistant D. immitis strains. Methods Dogs were inoculated with 50 D. immitis L3 and randomly allocated to treatments. Study 1: 6 groups of dogs (n = 8) were inoculated with JYD-34 (Day − 30) and treated as follows: T01, negative control; T02–T05, moxidectin at 3, 6, 12 or 24 µg/kg, respectively, on Day 0 only; T06, moxidectin at 3 µg/kg on Days 0, 30 and 60. Study 2: 10 groups of dogs (n = 5) were inoculated (Day − 30) with either JYD-34 (T01, T03–05) or ZoeLA (T02, T06–T10) and treated as follows: T01 and T02, negative controls; T03–T05, moxidectin at 24, 40 or 60 µg/kg, respectively, on Days 0, 28 and 56; T06 and T09, moxidectin at 3 or 60 µg/kg on Day 0 only; T07, T08 and T10, moxidectin at 24, 40 or 60 µg/kg, respectively, on Days 0, 28 and 56. Study 3: 5 groups of dogs (n = 5) were inoculated with ZoeMO (Day − 28) and treated as follows: T01, negative control; T02, moxidectin at 3 µg/kg moxidectin on Day 0 only; T03–T05, moxidectin at 24, 40 or 60 µg/kg, respectively, on Days 0, 28 and 56. All dogs were necropsied for adult heartworm recovery ~ 4–5 months post-inoculation. Results All moxidectin-treated dogs showed significantly lower worm counts than controls. The efficacy of moxidectin administered once at 3 µg/kg was 19% (JYD-34), 44.4% (ZoeLA) and 82.1% (ZoeMO). Increasing both the dose and the number of dosages of moxidectin improved efficacy, with 100% protection obtained using three dosages of moxidectin at either 40 µg/kg (JYD-34, ZoeMO) or 60 µg/kg (ZoeLA). Three dosages of 24 µg/kg were also highly effective, providing ≥ 98.8% efficacy for all three strains. Conclusions Increasing both the dose and number of consecutive monthly dosages of moxidectin improved the efficacy against ML-resistant heartworms. Based on these data and other technical considerations, the 24 µg/kg dose was considered the optimal dose for further commercial development.
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Affiliation(s)
- Tom L McTier
- Zoetis, Veterinary Medicine Research and Development, 333 Portage St, Kalamazoo, MI, 49007, USA.
| | - Robert H Six
- Zoetis, Veterinary Medicine Research and Development, 333 Portage St, Kalamazoo, MI, 49007, USA
| | - Aleah Pullins
- Zoetis, Veterinary Medicine Research and Development, 333 Portage St, Kalamazoo, MI, 49007, USA
| | - Sara Chapin
- Zoetis, Veterinary Medicine Research and Development, 333 Portage St, Kalamazoo, MI, 49007, USA
| | - Kristina Kryda
- Zoetis, Veterinary Medicine Research and Development, 333 Portage St, Kalamazoo, MI, 49007, USA
| | - Sean P Mahabir
- Zoetis, Veterinary Medicine Research and Development, 333 Portage St, Kalamazoo, MI, 49007, USA
| | - Debra J Woods
- Zoetis, Veterinary Medicine Research and Development, 333 Portage St, Kalamazoo, MI, 49007, USA
| | - Steven J Maeder
- Zoetis, Veterinary Medicine Research and Development, 333 Portage St, Kalamazoo, MI, 49007, USA
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Kryda K, Six RH, Walsh KF, Holzmer SJ, Chapin S, Mahabir SP, Myers M, Inskeep T, Rugg J, Cundiff B, Pullins A, Ulrich M, McCall JW, McTier TL, Maeder SJ. Laboratory and field studies to investigate the efficacy of a novel, orally administered combination product containing moxidectin, sarolaner and pyrantel for the prevention of heartworm disease (Dirofilaria immitis) in dogs. Parasit Vectors 2019; 12:445. [PMID: 31506094 PMCID: PMC6737634 DOI: 10.1186/s13071-019-3702-6] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2019] [Accepted: 09/04/2019] [Indexed: 12/17/2022] Open
Abstract
BACKGROUND Dirofilaria immitis is a filarial parasite of dogs that can cause serious or fatal cardiopulmonary disease. Three studies were conducted to evaluate the efficacy and safety of monthly treatment with moxidectin in a chewable tablet product in combination with sarolaner and pyrantel to prevent heartworm disease in dogs after experimental challenge and in a clinical field study in the USA. METHODS In two laboratory studies, dogs (8 per group) that had been inoculated 30 days prior with 50 third-stage D. immitis larvae were randomized to treatment on Day 0 with placebo or combination product, at the minimum dose of 24 µg/kg moxidectin, 2 mg/kg sarolaner and 5 mg/kg pyrantel (as pamoate salt). Study 2 also included groups treated with tablets containing moxidectin-alone (24 µg/kg) or sarolaner-alone (2 mg/kg). Efficacy was evaluated ~ 5 months after inoculation by adult heartworm counts at necropsy. In the field study, 410 dogs ≥ 8 weeks-old from 23 USA veterinary clinics were treated for 11 months with either combination product at 24-48 µg/kg moxidectin, 2-4 mg/kg sarolaner and 5-10 mg/kg pyrantel (n = 272) or Heartgard® Plus (ivermectin/pyrantel) at the label recommended dose rate (n = 138). Efficacy was evaluated on Day 330 using antigen and microfilaria testing to assess adult heartworm infection. RESULTS In the laboratory studies, there were no heartworms recovered from any dog treated with the combination product or moxidectin alone and all dogs treated with placebo or sarolaner-alone were infected with 20-44 adult heartworms. In the field study, all dogs treated with the combination product tested negative for heartworm infection on Day 330, whereas two dogs treated with Heartgard® Plus tested positive. The Heartgard® Plus-treated dogs that tested heartworm positive were from the lower Mississippi River Valley region, where heartworm resistance has been confirmed to occur. The combination product was well tolerated in all studies. CONCLUSIONS In laboratory studies, no heartworms were recovered from dogs treated with a single dose of the novel combination product containing moxidectin, sarolaner and pyrantel. Additionally, in the field study no dog tested positive for adult heartworm infection when dosed with the combination product monthly for 11 months, while two dogs treated with Heartgard® Plus tested positive.
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Affiliation(s)
- Kristina Kryda
- Veterinary Medicine Research and Development, Zoetis, Inc., 333 Portage St, Kalamazoo, MI 49007 USA
| | - Robert H. Six
- Veterinary Medicine Research and Development, Zoetis, Inc., 333 Portage St, Kalamazoo, MI 49007 USA
| | - Kelly F. Walsh
- Veterinary Medicine Research and Development, Zoetis, Inc., 333 Portage St, Kalamazoo, MI 49007 USA
| | - Susan J. Holzmer
- Veterinary Medicine Research and Development, Zoetis, Inc., 333 Portage St, Kalamazoo, MI 49007 USA
| | - Sara Chapin
- Veterinary Medicine Research and Development, Zoetis, Inc., 333 Portage St, Kalamazoo, MI 49007 USA
| | - Sean P. Mahabir
- Veterinary Medicine Research and Development, Zoetis, Inc., 333 Portage St, Kalamazoo, MI 49007 USA
| | - Melanie Myers
- Veterinary Medicine Research and Development, Zoetis, Inc., 333 Portage St, Kalamazoo, MI 49007 USA
| | - Tammy Inskeep
- Veterinary Medicine Research and Development, Zoetis, Inc., 333 Portage St, Kalamazoo, MI 49007 USA
| | - Jady Rugg
- Veterinary Medicine Research and Development, Zoetis, Inc., 333 Portage St, Kalamazoo, MI 49007 USA
| | - Blair Cundiff
- Veterinary Medicine Research and Development, Zoetis, Inc., 333 Portage St, Kalamazoo, MI 49007 USA
| | - Aleah Pullins
- Veterinary Medicine Research and Development, Zoetis, Inc., 333 Portage St, Kalamazoo, MI 49007 USA
| | - Michael Ulrich
- Cheri-Hill Kennel and Supply Inc., 17190 Polk Road, Stanwood, MI 49346 USA
| | | | - Tom L. McTier
- Veterinary Medicine Research and Development, Zoetis, Inc., 333 Portage St, Kalamazoo, MI 49007 USA
| | - Steven J. Maeder
- Veterinary Medicine Research and Development, Zoetis, Inc., 333 Portage St, Kalamazoo, MI 49007 USA
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McTier TL, Kryda K, Wachowski M, Mahabir S, Ramsey D, Rugg D, Mazaleski M, Therrien C, Adams E, Wolff T, Bowman DD. ProHeart® 12, a moxidectin extended-release injectable formulation for prevention of heartworm (Dirofilaria immitis) disease in dogs in the USA for 12 months. Parasit Vectors 2019; 12:369. [PMID: 31349867 PMCID: PMC6660952 DOI: 10.1186/s13071-019-3632-3] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2019] [Accepted: 07/20/2019] [Indexed: 12/17/2022] Open
Abstract
BACKGROUND 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. METHODS 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 (L3) 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. RESULTS 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. CONCLUSIONS 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.
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Affiliation(s)
| | | | | | | | | | | | | | | | - Eric Adams
- Northern Biomedical Research, Spring Lake, MI USA
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10
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Gomez SA, Picado A. Systemic insecticides used in dogs: potential candidates for phlebotomine vector control? Trop Med Int Health 2017; 22:755-764. [PMID: 28326655 DOI: 10.1111/tmi.12870] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Zoonotic visceral leishmaniasis (ZVL) is a public health problem endemic in some countries. Current control measures, in particular culling infected dogs, have not reduced ZVL incidence in humans. We evaluated the use of five systemic insecticides (spinosad, fluralaner, afoxolaner, sarolaner and moxidectin) currently used in dogs for other purposes (e.g. tick, flea control) in controlling ZVL transmission. The anti-phlebotomine capacity of these compounds confirmed in experimental studies makes their use in ZVL control programmes very promising. Limitations and benefits of using this new control tool are compared to current practices.
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Affiliation(s)
| | - Albert Picado
- Barcelona Institute for Global Health, Barcelona, Spain
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11
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Courtman N. Cytology of a subcutaneous mass in a dog. Aust Vet J 2016; 94:81-2. [PMID: 26914954 DOI: 10.1111/avj.12406] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2014] [Revised: 05/16/2015] [Accepted: 05/31/2015] [Indexed: 11/26/2022]
Affiliation(s)
- N Courtman
- Faculty of Veterinary Science, University of Melbourne, Werribee, Victoria, Australia.
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12
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Animal Health Markets and Opportunities: Companion Animal Landscape. ADVANCES IN DELIVERY SCIENCE AND TECHNOLOGY 2013. [DOI: 10.1007/978-1-4614-4439-8_2] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/05/2022]
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13
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Elimination of Dirofilaria (syn. Nochtiella) repens microfilariae in dogs with monthly treatments of moxidectin 2.5%/imidacloprid 10% (Advocate, Bayer) spot-on. Parasitol Res 2010; 106:1141-9. [PMID: 20165873 DOI: 10.1007/s00436-010-1783-4] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2009] [Accepted: 01/19/2010] [Indexed: 10/19/2022]
Abstract
Elimination of microfilaria in dogs infected with zoonotic Dirofilaria repens would be desirable to reduce further spread. Moxidectin has demonstrated efficacy against microfilariae and safety in dogs infected with Dirofilaria immitis and could be an option for controlling D. repens microfilariae. A field study with 64 dogs previously confirmed positive for D. repens microfilaria was conducted in Hungary, in which a spot-on product (Advocate, Bayer) was tested. Treatments were applied to 44 dogs once a month for 3 months (five dogs) or 6 months (22 dogs), alternatively every 2 weeks for 6 months (17 dogs). Twenty dogs remained untreated. Microfilaria counts were performed once a month and for a further 6 months following the last treatment. Two weeks after the first treatment, 38 of 44 dogs were microfilaria negative. Four weeks after the initial treatment, one dog still showed a low microfilaria count. Following the second treatment, all treated dogs were negative. This status was maintained during the 6-month observation period after the last treatment. These data demonstrate the successful long-lasting elimination of microfilariae. Moreover, it may be supposed that adult D. repens were killed based on the observation that no further microfilariae were seen up to 6 months after the end of the treatment period.
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14
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Sanchez Bruni SF, Jones DG, McKellar QA. Pharmacological approaches towards rationalizing the use of endoparasitic drugs in small animals. J Vet Pharmacol Ther 2006; 29:443-57. [PMID: 17083448 DOI: 10.1111/j.1365-2885.2006.00806.x] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
Parasitic diseases are an important health concern to small animal veterinarians worldwide, and their zoonotic potential is also of relevance to human medicine. The treatment and control of such conditions relies heavily on pharmaceutical intervention using a range of antiparasitic drugs and/or their biologically active metabolites. Broad spectrum agents have been produced, although narrow and even monospecific drugs are used in some situations. Their efficacy may depend on dosage, the target pathogen(s), the host species and/or the site of infection. Optimal use of antiparasitics requires a detailed consideration of the pharmacokinetic and pharmacodynamic properties of the drugs in specific clinical contexts. This review summarizes the present status of knowledge on the metabolism, and physicochemical and pharmacological properties of the major antiparasitic drugs currently used in small animal veterinary practice. In addition, data relevant to therapeutic dosage, efficacy and clinical indication/contraindication, particularly in relation to combination drug therapy, are included.
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Affiliation(s)
- S F Sanchez Bruni
- Pharmacology Laboratory, Veterinary Medicine Faculty, Universidad Nacional del Centro, Tandil (7000), Argentina.
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15
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Cunningham CP, Brown JM, Jacobson GA, Brandon MR, Martinod SR. Evaluation of a covered-rod silicone implant containing ivermectin for long-term prevention of heartworm infection in dogs. Am J Vet Res 2006; 67:1564-9. [PMID: 16948602 DOI: 10.2460/ajvr.67.9.1564] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
OBJECTIVE To evaluate use of covered-rod (CR) silicone implants containing ivermectin for long-term prevention of infection with Dirofilaria immitisin dogs. ANIMALS 145 adult male and female dogs. PROCEDURES Dogs received implants of different sizes, and ivermectin concentrations and serum ivermectin concentrations were monitored for 16, 57, and 56 weeks, respectively, in 3 preclinical dose selection studies. Ability of implants to prevent infection with D immitis was evaluated in 2 further studies; dogs were challenged with 50 infective third-stage larvae 52 weeks after implant administration and necropsied 145 days after challenge, and the total number of adult heartworms was counted. A field study was then undertaken in which client-owned dogs received an implant and plasma samples were collected at intervals until week 52 for ivermectin analysis and heartworm antigen determination. RESULTS Use of the implants resulted in maintenance of an ivermectin concentration > or = 0.2 ng/mL for 12 months. In challenge studies, no treated dogs had adult heartworms, in contrast to untreated dogs, which all had adult heartworms at necropsy. In the field study, dogs treated with an implant had negative results of heartworm antigen testing for 12 months. CONCLUSIONS AND CLINICAL RELEVANCE The CR silicone implant containing 7.3 mg of ivermectin was 100% effective in preventing experimental infection with D immitislarvae and resulted in negative results for heartworm antigen in a field trial. This product has the potential to alleviate poor owner compliance with monthly prevention regimens.
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Affiliation(s)
- Craig P Cunningham
- Smart Drug Systems Inc, Ste 102, 181 S Broad St, Pawcatuck, CT 06379, USA
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16
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Heaney K, Lindahl RG. Safety evaluation of moxidectin sustained-release injectable in 10-week-old puppies. Vet Parasitol 2005; 133:227-31. [PMID: 16171949 DOI: 10.1016/j.vetpar.2005.04.003] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
A study was conducted to evaluate the safety of a commercial formulation of moxidectin sustained-release injectable for dogs (ProHeart 6, Fort Dodge Animal Health) administered as a single subcutaneous dose to 10-week-old puppies. Twelve male and 12 female purpose-bred beagles 10 weeks of age were blocked by weight within gender and randomly allocated to three treatment groups. Puppies in two groups were treated with moxidectin sustained-release injectable for dogs at three or five times the labeled dose rate of 0.17 mg moxidectin/kg. The third group was treated with saline solution as controls. Physical and neurologic status, hematologic parameters, clinical chemistries, urine samples, body weight, and food consumption were evaluated before and up to 12 weeks after treatment. When compared to controls, mild depression of erythropoiesis, characterized by reduced hemoglobin, reticulocytes, erythrocytes, and hematocrit, was noted in puppies treated with five times the label dose of moxidectin sustained-release injectable. Values for these parameters remained within normal ranges and increased during the study, but at a reduced rate relative to saline-treated controls. Other parameters evaluated remained within normal limits for all treatment groups. Based on results of this study, the no observed adverse effect level for moxidectin sustained-release injectable (ProHeart 6) treatment in 10-week-old puppies was determined to be three times the recommended rate.
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Affiliation(s)
- Kathleen Heaney
- Fort Dodge Animal Health, P.O. Box 5366 Princeton, NJ 08543, USA.
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Lok JB, Washabau RJ, Heaney K, Nolan TJ, Hendrick MJ, Neumann NR, Ulrich M. Six-month prophylactic efficacy of moxidectin sustained release (SR) injectable for dogs against experimental heartworm infection in growing puppies. Vet Parasitol 2005; 133:233-41. [PMID: 16085364 DOI: 10.1016/j.vetpar.2005.06.019] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
The purpose of this study was to assess the efficacy of moxidectin sustained release injectable for dogs (moxidectin SR, Fort Dodge Animal Health) in protecting growing puppies from experimental infection with the heartworm, Dirofilaria immitis, six months after treatment. The study involved 27 puppies, approximately 12 weeks of age at the beginning of the study, with nine puppies in each of three size classes. The small breed class included eight Pekingese and one purpose-bred small breed mongrel; the medium breed class included nine purpose-bred mongrels, and the large breed class included nine puppies with an anticipated adult weight >or=30-35 kg. Both genders were included with no attempt made to have equal numbers of male and female puppies. Puppies were blocked by weight within each size class and randomly assigned to three treatment groups of nine dogs. On Day 0, pups in two groups were injected subcutaneously with moxidectin SR, dosed to deliver 0.17 mg moxidectin/kg b.w. The third group was injected with sterile saline. Personnel making observations were blinded to the treatment status of the animals. Following treatment, puppies were observed for signs of adverse local and systemic reactions. Puppy weights and serum moxidectin levels were also monitored. On Day 180, puppies in all treatment groups were inoculated subcutaneously with 50 third-stage larvae of D. immitis. On Days 348 and 349, puppies were euthanatized and necropsied. Hearts and lungs were examined for adult heartworms. All animals in the saline control group were infected with an arithmetic mean of 39.22 adult heartworms each. Seventeen of 18 dogs in the moxidectin SR-treated groups were uninfected. One treated puppy was infected with a single adult heartworm. This infected individual was from the large breed size class and had the second highest percent increase in body weight. Based on arithmetic means, the heartworm recovery from all treated puppies represents a 99.86% reduction relative to the saline control. There were no adverse local or systemic reactions to treatment in any animal.
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Affiliation(s)
- James B Lok
- Department of Pathobiology, School of Veterinary Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA.
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18
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Bianciardi P, Otranto D. Treatment of dog thelaziosis caused by Thelazia callipaeda (Spirurida, Thelaziidae) using a topical formulation of imidacloprid 10% and moxidectin 2.5%. Vet Parasitol 2005; 129:89-93. [PMID: 15817208 DOI: 10.1016/j.vetpar.2004.12.020] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2004] [Revised: 12/02/2004] [Accepted: 12/13/2004] [Indexed: 10/25/2022]
Abstract
Canine thelaziosis caused by Thelazia callipaeda infects dogs, cats, foxes, rabbits, and humans resulting in conjunctivitis, pain and excessive lacrimation. T. callipaeda live in the eyes under the nictitating membrane and females release first stage larvae which are ingested by flies which act as intermediate hosts. Control of canine thelaziosis is currently based on the removal of nematodes directly from the eyes of affected dogs or on the local instillation of antiparasitic drugs. With the aim of evaluating the efficacy against T. callipaeda of an association of imidacloprid 10% and moxidectin 2.5% by spot-on formulation administered via dermal application, three groups of naturally infected animals were selected: i.e. group A (21 dogs) received a single dose of imidacloprid 10% and moxidectin 2.5% by spot-on; group B (21 dogs) received a single dose of imidacloprid 10% by spot-on and group C (20 dogs) were left untreated. The efficacy of treatments was established by eye inspection and parasite viability and vitality after 1, 5 and 9 days after animal treatments (groups A and B) and after 9 days only in untreated animals (group C). Imidacloprid 10% and moxidectin 2.5% in spot-on formulation showed to be effective with regards the control of dog thelaziosis within 5 (90.47%) to 9 (95.23%) days after treatment. Only one dog from group A presented nematodes after treatment. The presence of parasites in the eyes of dogs from groups B (imidacloprid 10%) and C confirm that the anthelmintic efficacy against T. callipaeda in animal from group A (imidacloprid 10% and moxidectin 2.5%) was most likely attributable to moxidectin 2.5%. The spot-on formulation containing imidacloprid 10% and moxidectin 2.5% is very easy to apply and helps overcome problems linked to the mechanical removal of parasites or to the restraining of the animals for the local instillation of drugs in the eyes.
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Lok JB, Knight DH, Nolan TJ, Grubbs ST, Cleale RM, Heaney K. Efficacy of an injectable, sustained-release formulation of moxidectin in preventing experimental heartworm infection in mongrel dogs challenged 12 months after administration. Vet Parasitol 2005; 128:129-35. [PMID: 15725542 DOI: 10.1016/j.vetpar.2004.11.010] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 11/04/2004] [Indexed: 11/26/2022]
Abstract
The objective of this study was to ascertain the ability of a single subcutaneous injection of a sustained-release (SR) formulation of moxidectin to protect dogs against challenge inoculation with infective Dirofilaria immitis larvae 364 days after administration. Twenty four purpose-bred adult mixed-breed dogs were grouped into three blocks of eight based on weight and sex. Saline solution (0.9% NaCl) or a moxidectin SR formulation at volumes designed to deliver 0.17 or 0.27 mg moxidectin/kg b.w. was injected subcutaneously on day 0. Throughout the post-treatment period, injection sites of all dogs were periodically examined visually and by palpation. Palpable swellings were characterized as to size, consistency and the presence of associated pain or erythema. On day 364, each dog was inoculated subcutaneously with 50 D. immitis L3. On days 510 and 511, dogs were euthanatized, and their hearts, lungs and thoracic cavities were inspected for the presence of adult heartworms. number, sex and viability of recovered heartworms were determined. The mean number of heartworms recovered from dogs that had received the saline control injection was 35.7. No heartworms were recovered from any dog treated with either 0.17 or 0.27 mg moxidectin/kg b.w. For variable periods of time following treatment, small (1-4 mm diameter), firm, subcutaneous swellings could be palpated at the injection sites of dogs treated with 0.17 or 0.27 mg moxidectin/kg b.w. These swellings contracted progressively and eventually disappeared except for the case of one animal treated with 0.27 mg/kg, in which the swelling persisted for the entire study period. At no time during the study was pain or erythema noted at the injection site of any dog, and no dog exhibited any adverse systemic reaction related to treatment. We conclude that under conditions pertaining in this study, a single subcutaneous injection of a moxidectin SR formulation at dosing rates of either 0.17 or 0.27 mg/kg b.w. can safely protect adult dogs against experimental challenge inoculation with infective heartworm larvae for a period of 12 months.
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Affiliation(s)
- James B Lok
- Department of Pathobiology, School of Veterinary Medicine, University of Pennsylvania, Philadelphia, PA 19104-6050, USA.
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Holm-Martin M, Atwell R. Evaluation of a single injection of a sustained-release formulation of moxidectin for prevention of experimental heartworm infection after 12 months in dogs. Am J Vet Res 2005; 65:1596-9. [PMID: 15566101 DOI: 10.2460/ajvr.2004.65.1596] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
OBJECTIVE To evaluate the efficacy of a single injection of a sustained-release formulation of moxidectin in preventing heartworm (Dirofilaria immitis) infection for 12 months in dogs. ANIMALS 14 healthy dogs. PROCEDURE Group A (nontreated control dogs; n = 6) received sterile vehicle administered SC, and group B (treated dogs; n = 6) received a sustained-release formulation of moxidectin administered SC. All dogs were housed in a heartworm-endemic area for 11.5 months, and heartworm antigen and modified Knott tests were performed monthly. All dogs (including 2 additional control dogs [group C]) were then inoculated with infective-stage larvae (L3) of D. immitis, and 4.5 months later, all dogs were euthanatized and post-mortem examinations were performed. Adult D. immitis were counted and measured, and their age was estimated. RESULTS All dogs in groups A and C were infected with young (4- to 4.5-month old) adult male and female D. immitis. No dogs in group B were infected with heartworms. CONCLUSIONS AND. CLINICAL RELEVANCE The age of heartworms recovered suggests that infection was the result of experimental inoculation and not natural exposure to mosquitoes during the 11.5-month period the dogs resided in a heartworm-endemic area. A single SC injection of a sustained-release formulation of moxidectin was effective in providing protection against heartworm infection after 12 months in dogs. This formulation is a convenient method of heartworm prophylaxis that could eliminate the problem of poor owner compliance.
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Affiliation(s)
- Merete Holm-Martin
- Fort Dodge Australia Pty Ltd, PO Box 6024, Baulkham Hills BC, NSW, 2153, Australia
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Lia RP, Traversa D, Agostini A, Otranto D. Field efficacy of moxidectin 1 per cent against Thelazia callipaeda
in naturally infected dogs. Vet Rec 2004; 154:143-5. [PMID: 14979443 DOI: 10.1136/vr.154.5.143] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Affiliation(s)
- R P Lia
- Dipartimento di Sanità e Benessere degli Animali, Facoltà di Medicina Veterinaria, Strada Provinciale per Casamassima Km 3, 70010 Valenzano, Bari, Italy
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Rossi L, Ferroglio E, Agostini A. Use of an injectable, sustained-release formulation of moxidectin to prevent canine subcutaneous dirofilariosis. Vet Rec 2004; 154:26-7. [PMID: 14725427 DOI: 10.1136/vr.154.1.26] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Affiliation(s)
- L Rossi
- Dipartimento di Produzioni Animali, Epidemiologia ed Ecologia, Università degli Studi di Torino, Via Leonardo da Vinci 44, 10095 Grugliasco, Italy
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Abstract. Vet Rec 2004. [DOI: 10.1136/vr.154.1.27] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
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Genchi C, Rossi L, Cardini G, Kramer LH, Venco L, Casiraghi M, Genchi M, Agostini A. Full season efficacy of moxidectin microsphere sustained release formulation for the prevention of heartworm (Dirofilaria immitis) infection in dogs. Vet Parasitol 2002; 110:85-91. [PMID: 12446092 DOI: 10.1016/s0304-4017(02)00325-4] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
The authors report the efficacy of an injectable, moxidectin sustained release (SR) formulation for the prevention of canine heartworm infection in endemic areas in northern and central Italy. Three field trials were carried out on a total of 324 dogs. Two hundred forty-three dogs were treated with moxidectin SR 6 months apart and 81 dogs (positive controls) with moxidectin tablets given monthly for 5 consecutive months during the risk season each year throughout the study. Results of testing for microfilariae and circulating adult female antigens were negative for all the experimentally treated dogs at the 6, 7, 11 and 19 months after the last injection. No adverse reactions to moxidectin SR were observed but a moderate pain at palpation and swelling (5-6 cm) at the injection site after the first treatment. In the study areas, prevalence of Dirofilaria immitis infection calculated by testing dogs which had no preventive treatment in the previous transmission season ranged from 33 to 63%. This study confirms the efficacy and safety of injectable, moxidectin SR formulation in the prevention of heartworm infection in dogs and demonstrates that the prophylactic efficacy lasts for the full season and strongly suggests that the product gives 1-year protection.
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Affiliation(s)
- Claudio Genchi
- Dipartimento di Patologia Veterinaria, Igiene e Salute Pubblica Veterinaria, Università degli Studi, via Celoria 10, 20133 Milan, Italy.
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