A prospective, randomized, double-blind, placebo-controlled multisite, parallel-group field study in dogs with osteoarthritis conducted in the United States of America evaluating bedinvetmab, a canine anti-nerve growth factor monoclonal antibody.

OBJECTIVE: Bedinvetmab, a fully canine anti-nerve growth factor monoclonal antibody, was evaluated in dogs for control of osteoarthritis-related pain in a study conducted to support registration in the USA. STUDY DESIGN: Randomized, double-blind, placebo-controlled, multicenter, parallel-group study. ANIMALS: General practice client-owned dogs with osteoarthritis (n = 272). METHODS: Dogs were block randomized 1:1 to placebo (saline, n = 137) or bedinvetmab (n = 135; 0.5-1.0 mg kg-1) administered subcutaneously, once monthly. The primary end point, day 28 Canine Brief Pain Inventory (CBPI) treatment success (TS), required pain severity score (PSS; 0-10) decrease ≥1 and pain interference score (PIS; 0-10) decrease ≥ 2. CBPI TS rates [and number needed to treat (NNT)], change in scores [and standardized effect size (ES)], change in quality of life (QoL) and bedinvetmab half-life were calculated. RESULTS: Significant (p < 0.05) improvement with bedinvetmab over placebo occurred (days 28, 42, 56, 84) for CBPI TS. Of cases evaluable for day 28 CBPI TS (placebo, n = 131; bedinvetmab, n = 128), success rates were 36.6% and 47.4%, respectively (p = 0.0410) (NNT, 9.3; PSS and PIS ES, 0.3). CBPI TS increased after the second dose in both groups, plateaued for bedinvetmab at day 42 and decreased for placebo beginning day 84. Day 84 NNT (4.3), PSS (0.4) and PIS (0.5) showed continued improvement with monthly dosing. After the first dose, mean (± standard deviation) bedinvetmab half-life was 19.1 (8.3) days. Adverse events were similar between groups and not considered treatment-related. There was a significant effect of bedinvetmab versus placebo on all CBPI components (PIS, PSS, QoL). CONCLUSIONS AND CLINICAL RELEVANCE: These results corroborated those previously reported and provide further support of safety and effectiveness of bedinvetmab (0.5-1.0 mg kg-1) administered subcutaneously at monthly intervals to dogs for control of osteoarthritis-related pain.

Laboratory safety evaluation of lokivetmab, a canine anti-interleukin-31 monoclonal antibody, in dogs.

Lokivetmab (Cytopoint®, Zoetis) is a canine monoclonal antibody that specifically binds and neutralizes interleukin (IL)-31. Lokivetmab is approved for use in dogs for the treatment of atopic dermatitis (AD) and allergic dermatitis. The laboratory safety of lokivetmab was evaluated in 2 studies by adapting the science-based, case-by-case approach used for preclinical and early clinical safety evaluation of human biopharmaceuticals. The main objectives were to demonstrate the safety of lokivetmab in healthy laboratory Beagle dogs by using integrated clinical, morphologic, and functional evaluations. In Study 1, dogs were treated s.c. with saline or lokivetmab at 3.3 mg/kg (1X, label dose) or 10 mg/kg (3X intended dose) for 7 consecutive monthly doses, with terminal pathology and histology assessments. In Study 2, the functional immune response was demonstrated in naïve dogs using the T-cell dependent antibody response (TDAR) test with 2 different dose levels of unadjuvanted keyhole limpet hemocyanin (KLH) as the model immunogen. The primary endpoint was anti-KLH IgG antibody titer, and secondary endpoints were ex vivo IL-2 enzyme-linked immunospot (ELISpot) and peripheral blood mononuclear cell lymphoproliferation assays. Both studies included monitoring general health, periodic veterinary clinical evaluations, serial clinical pathology and toxicokinetics, and monitoring for anti-drug antibodies. In both studies, the health of dogs receiving lokivetmab was similar to controls, with no treatment-related changes uncovered. Extensive pathology evaluations of immune tissues (Study 1) revealed no lokivetmab-related morphologic changes, and in dogs treated at 10 mg/kg lokivetmab, immunization with the model antigen KLH did not impair the functional antibody or T-cell recall responses. There were no immunogenicity-related or hypersensitivity-related responses observed in either study. These studies in healthy laboratory dogs showed that lokivetmab was well-tolerated, did not produce any treatment-related effects, and had no effect on immune system morphology or its functional response. These studies also demonstrated the utility of a science-based case-by-case approach to the safety evaluation of a veterinary biopharmaceutical product.

A prospective, randomized, blinded, placebo-controlled multisite clinical study of bedinvetmab, a canine monoclonal antibody targeting nerve growth factor, in dogs with osteoarthritis.

OBJECTIVE: Bedinvetmab is a canine monoclonal antibody targeting nerve growth factor. This study evaluated the efficacy and safety of bedinvetmab for alleviation of pain associated with osteoarthritis in dogs. STUDY DESIGN: Double-blind, randomized, multicentre, placebo-controlled study. ANIMALS: Client-owned dogs (n = 287) with osteoarthritis. METHODS: Dogs were randomized (1:1) to subcutaneous injection with placebo (saline, n = 146) or bedinvetmab (0.5-1.0 mg kg-1, n = 141) administered monthly. After 3 months, 89 bedinvetmab-treated dogs that responded positively based on owner and veterinarian assessments were administered up to six additional doses of bedinvetmab in a single-armed open-label continuation phase. The primary efficacy end point was treatment success based on the owner-assessed canine brief pain inventory (CBPI) on day 28. Treatment success was defined as ≥ 1 reduction in pain severity score (0-10) and ≥ 2 in pain interference score (0-10). RESULTS: Percentage treatment success was significantly greater in the bedinvetmab group than in the placebo group from day 7 through all assessed time points (p ≤ 0.0025). On day 28, 43.5% of dogs achieved treatment success with bedinvetmab compared with placebo (16.9%) (p = 0.0017). Treatment success continued through days 56 (50.8%) and 84 (48.2%) in the bedinvetmab group and was < 25% in the placebo group at all time points. Sustained efficacy was demonstrated in the continuation phase. Adverse health events occurred at similar frequencies in both groups. They were considered typical for a population of dogs with osteoarthritis and not related to study treatment. Treatment with bedinvetmab demonstrated a significant effect on all three components of CBPI-pain interference, pain severity, quality of life. CONCLUSIONS AND CLINICAL RELEVANCE: This study demonstrated the effectiveness and safety of bedinvetmab administered monthly for up to 9 months at 0.5-1.0 mg kg-1 for alleviation of pain associated with canine osteoarthritis.

Pharmacokinetics and Immunogenicity of Frunevetmab in Osteoarthritic Cats Following Intravenous and Subcutaneous Administration.

Osteoarthritis and other degenerative joint diseases are common causes of chronic pain in cats. Frunevetmab is a felinized monoclonal antibody that binds to nerve growth factor (NGF) and provides relief from pain by blocking the receptor-mediated signaling cascade induced by NGF. Results from three studies were combined to provide an overview of frunevetmab pharmacokinetics (PK) and immunogenicity. The objective of the first study was to establish the pharmacokinetic parameters resulting from intravenous (IV) and subcutaneous (SC) administration of frunevetmab to the feline patient population at 3 mg/kg. Ten adult cats with naturally-occurring osteoarthritis were administered frunevetmab in a crossover design at 28 day intervals. Non-compartmental pharmacokinetic analysis of the plasma concentration-time data showed that the half-life was 10.1 ± 1.9 days after IV dosing and the SC bioavailability was 60.3 ± 15.8% with maximum drug levels observed at 3-7 days after dosing. Plasma samples were collected at ~28 days after dosing during two field safety and effectiveness studies of cats with degenerative joint disease. The doses ranged from 1.0 to 2.8 mg/kg; 2 or 3 doses were administered either SC/IV, SC/SC, or SC/SC/SC. The data from these studies along with the data from the laboratory pharmacokinetic study were analyzed using non-linear mixed-effects (NLME) modeling. The model closely predicted the trough concentrations from the two field studies, including the IV treatment in the pilot field study. The trough concentrations were predicted to be close to steady-state after 2 doses. A second objective was to determine the incidence and clinical relevance of frunevetmab immunogenicity. A three-tier anti-drug antibody assay (screen, confirm, titer) was developed and validated. Immunogenicity was assessed in 259 frunevetmab-treated animals enrolled in the two field studies. Only 4 of these animals (1.5%) appeared to develop immunogenicity to frunevetmab. None of the four exhibited adverse events attributed to immunogenicity and no impact on drug levels or efficacy was observed in three of the animals. In the placebo animals, 2.3% (3/131) appeared to develop treatment-emergent immunogenicity. Overall, frunevetmab administration resulted in a very low incidence of treatment-emergent immunogenicity with no safety findings and minimal effect on drug exposure and efficacy.

Onset and duration of action of lokivetmab in a canine model of IL-31 induced pruritus.

BACKGROUND: Interleukin (IL)-31 is a cytokine involved in allergic inflammation which induces pruritus across species including dogs. Using recombinant canine IL-31 we have developed a model of pruritus in the dog to evaluate onset of action and duration of effect of therapeutic drugs. OBJECTIVE: To assess the onset of action and duration of effect of lokivetmab (Cytopoint) in the IL-31-induced pruritus model. ANIMALS: Twenty-four purpose-bred beagle dogs (neutered males, spayed and intact females) 1.5-4.7 years old and weighing between 6 and14 kg. METHODS AND MATERIALS: Randomized, blinded, placebo-controlled studies were designed to evaluate the antipruritic properties of lokivetmab. Laboratory beagle dogs were given either placebo, 0.125, 0.5 or 2.0 mg/kg lokivetmab, subcutaneously. IL-31 then was administered to evaluate pruritus 3-5 h post-placebo or -lokivetmab administration as well as one, seven, 14, 28, 42 and 56 days post-dosing. Pruritus was evaluated over a 2 h window in animals by video monitoring and scored using a categorical scoring system. RESULTS: When animals were given 2.0 mg/kg lokivetmab, a significant reduction in pruritus was observed at 3-4, 4-5 and 3-5 h post-treatment (P ≤ 0.0001). When animals were given either 0.125, 0.5 or 2 mg/kg lokivetmab, the duration of effect was dose-dependent and statistically significant for 14, 28 and 42 days, respectively (P ≤ 0.0288). CONCLUSION: These data indicate that a single subcutaneous injection of 2 mg/kg lokivetmab produces a significant suppression of pruritus starting 3 h post-treatment that can be sustained for 42 days.

A blinded, randomized clinical trial evaluating the efficacy and safety of lokivetmab compared to ciclosporin in client-owned dogs with atopic dermatitis.

BACKGROUND: Lokivetmab is an injectable anti-canine-IL-31 monoclonal antibody to treat clinical manifestations of atopic dermatitis (AD) in dogs. HYPOTHESIS/OBJECTIVES: To characterize the efficacy and safety of lokivetmab, and to demonstrate its noninferiority to ciclosporin under field conditions. ANIMALS: Dogs with chronic AD (n = 274) were enrolled from 40 practices in Belgium, The Netherlands, France and Germany. METHODS: Animals were randomized (1:1) to oral ciclosporin (5 mg/kg/once daily) or monthly injectable lokivetmab (1-3.3 mg/kg) for three months. Eighty one animals that successfully completed the comparative phase were enrolled in a continuation phase receiving lokivetmab for an additional six months. Owners assessed pruritus on a Visual Analog Scale, skin lesions were assessed by veterinary investigators with a Canine AD Extent and Severity Index (CADESI-03) scale. RESULTS: Lokivetmab was noninferior to ciclosporin for pruritus reduction on Day 28 (51.90% versus 43.72%). For Day 28 CADESI-03 percentage reduction, noninferiority of lokivetmab (54.17) versus ciclosporin (56.86%) was not achieved. At none of the time points were mean CADESI-03 scores significantly different between groups. Continued efficacy towards pruritus and lesions was demonstrated in the continuation phase where 76.3% of animals (n = 45) were assessed as 'normal' for pruritus at study end. No abnormal health events associated with lokivetmab were observed during the initial three month phase (142 dogs) or during the subsequent six month phase (81 dogs). CONCLUSIONS AND CLINICAL IMPORTANCE: Lokivetmab at a minimum monthly dose of 1 mg/kg provided quick onset (within one day) of a lasting effect in reducing pruritus and skin lesions with a good safety profile.

A blinded, randomized, placebo-controlled trial of the safety of lokivetmab (ZTS-00103289), a caninized anti-canine IL-31 monoclonal antibody in client-owned dogs with atopic dermatitis.

BACKGROUND: Lokivetmab (ZTS-00103289) is a caninized anti-canine IL-31 monoclonal antibody that has demonstrated efficacy in reducing pruritus associated with atopic dermatitis (AD) in dogs in field trials. HYPOTHESIS/OBJECTIVES: This study evaluated the safety of lokivetmab in a randomized, double blind, placebo-controlled trial in client owned dogs with AD with minimal restrictions on concomitant medications and co-morbidities. ANIMALS: Clinicians at 14 veterinary clinics enrolled client owned dogs (n = 245) with chronic AD. METHODS: Dogs were randomized at a 2:1 ratio to receive either lokivetmab (1.0-3.3 mg/kg) or placebo administered subcutaneously on days 0 and 28. Clinicians examined dogs, and collected blood and urine for assessment of clinical pathology and immunogenicity (days 0, 28 and 42). RESULTS: There were no immediate hypersensitivity reactions (e.g. wheals, vomiting). Discomfort at administration occurred in 5.1% of dogs and was similar in frequency and severity between lokivetmab- and placebo-treated groups. Pruritus was reported as an adverse event during the study less frequently in the lokivetmab-treated group (4.9% and 19.3%, respectively); otherwise, adverse events occurred at a similar frequency between treatment groups. There were no clinically important differences between groups in clinical pathology results. Treatment-induced immunogenicity was found in 2.5% of lokivetmab treated dogs. A wide variety of concomitant medications were used with no clinically apparent adverse interactions. CONCLUSIONS AND CLINICAL IMPORTANCE: Among a diverse population of 162 client owned dogs with a clinical diagnosis of AD, treatment with two monthly doses of lokivetmab was safe, based on observed adverse events and clinical pathology results over a 42 day period.

A blinded, randomized, placebo-controlled, dose determination trial of lokivetmab (ZTS-00103289), a caninized, anti-canine IL-31 monoclonal antibody in client owned dogs with atopic dermatitis.

BACKGROUND: Pruritus is the hallmark clinical sign of atopic dermatitis (AD) in dogs. Lokivetmab, a caninized anti-canine IL-31 monoclonal antibody, reduced pruritus and associated inflammatory skin lesions in a proof-of-concept study in dogs with AD. HYPOTHESIS/OBJECTIVES: The objective was to describe lokivetmab dose response in a randomized, double blind, placebo-controlled trial. ANIMALS: Clinicians at 15 referral clinics enrolled 211 client owned dogs with a history of chronic AD. METHODS: Dogs were randomized to treatment with lokivetmab (0.125, 0.5 or 2.0 mg/kg) or placebo administered subcutaneously once on Day 0. Dog owners assessed visual analog scale (VAS) scores of pruritus on days 0, 1, 2, 3, 7, 14, 21, 28, 35, 42, 49 and 56. Clinicians assessed Canine AD Extent and Severity Index (CADESI-03) scores on days 0, 7, 14, 28, 42 and 56. RESULTS: Treatment with lokivetmab (2 mg/kg) resulted in a greater percentage reduction from baseline in owner assessed pruritus (days 1-49) and clinician assessed CADESI-03 scores (days 7-56) compared to placebo (P < 0.05); differences were achieved in lower dose groups but at later time points and for shorter duration for both owner assessed pruritus (0.5 mg/kg, days 2-35; 0.125 mg/kg, days 7-21) and clinician assessed CADESI-03 scores (0.5 mg/kg and 0.125 mg/kg, Day 14). CONCLUSIONS AND CLINICAL IMPORTANCE: Lokivetmab (0.5, 2.0 mg/kg) reduced pruritus compared to placebo for at least 1 month. Level and duration of response increased with increasing dose. Further studies are needed to better understand variability in individual responses across a broader population of dogs with AD.

Current cytochrome P450 phenotyping methods applied to metabolic drug-drug interaction prediction in dogs.

Recombinant cytochrome P450 (P450) phenotyping, different approaches for estimating fraction metabolized (f(m)), and multiple measures of in vivo inhibitor exposure were tested for their ability to predict drug interaction magnitude in dogs. In previous reports, midazolam-ketoconazole interaction studies in dogs have been attributed to inhibition of CYP3A pathways. However, in vitro phenotyping studies demonstrated higher apparent intrinsic clearances (CL(int,app)) of midazolam with canine CYP2B11 and CYP2C21. Application of activity correction factors and isoform hepatic abundance to liver microsome CL(int,app) values further implicated CYP2B11 (f(m) >or= 0.89) as the dog enzyme responsible for midazolam- and temazepam-ketoconazole interactions in vivo. Mean area under the curve (AUC) in the presence of the inhibitor/AUC ratios from intravenous and oral midazolam interaction studies were predicted well with unbound K(i) and estimates of unbound hepatic inlet inhibitor concentrations and intestinal metabolism using the AUC-competitive inhibitor relationship. No interactions were observed in vivo with bufuralol, although significant interactions with bufuralol were predicted with fluoxetine via CYP2D and CYP2C pathways (>2.45-fold) but not with clomipramine (<2-fold). The minor caffeine-fluvoxamine interaction (1.78-fold) was slightly higher than predicted values based on determination of a moderate f(m) value for CYP1A1, although CYP1A2 may also be involved in caffeine metabolism. The findings suggest promise for in vitro approaches to drug interaction assessment in dogs, but they also highlight the need to identify improved substrate and inhibitor probes for canine P450s.

Discovery of N-[(3R,5R)-1-azabicyclo[3.2.1]oct-3-yl]furo[2,3-c]pyridine-5-carboxamide as an agonist of the alpha7 nicotinic acetylcholine receptor: in vitro and in vivo activity.

A novel alpha7 nAChR agonist, N-[(3R,5R)-1-azabicyclo[3.2.1]oct-3-yl]furo[2,3-c]pyridine-5-carboxamide (3a, PHA-709829), has been identified for the potential treatment of cognitive deficits in schizophrenia. The compound shows potent and selective alpha7 in vitro activity, excellent brain penetration, good rat oral bioavailability and robust in vivo efficacy in a rat auditory sensory gating model.

Design, synthesis, structure-activity relationship, and in vivo activity of azabicyclic aryl amides as alpha7 nicotinic acetylcholine receptor agonists.

A novel set of azabicyclic aryl amides have been identified as potent and selective agonists of the alpha7 nAChR. A two-pronged approach was taken to improve the potential hERG liability of previously disclosed alpha7 nAChR agonist, PNU-282,987, while maintaining the compound's other desirable pharmacological properties. The first approach involved further exploration of the aryl carboxylic acid fragment of PNU-282,987, while the second approach focused on modification of the azabicyclic amine portion of PNU-282,987. The best compounds from each series are characterized by rapid brain penetration, good oral bioavailability in rat, and demonstrate in vivo efficacy in a rat P50 auditory sensory gating assay. At least one analog from each series (1h, 1o, 2a, 9a, and 18a) shows an improved hERG safety profile over PNU-282,987.

Discovery of N-[(3R)-1-azabicyclo[2.2.2]oct-3-yl]furo[2,3-c]pyridine-5-carboxamide, an agonist of the alpha7 nicotinic acetylcholine receptor, for the potential treatment of cognitive deficits in schizophrenia: synthesis and structure--activity relationship.

N-[(3R)-1-Azabicyclo[2.2.2]oct-3-yl]furo[2,3-c]pyridine-5-carboxamide (14, PHA-543,613), a novel agonist of the alpha7 neuronal nicotinic acetylcholine receptor (alpha7 nAChR), has been identified as a potential treatment of cognitive deficits in schizophrenia. Compound 14 is a potent and selective alpha7 nAChR agonist with an excellent in vitro profile. The compound is characterized by rapid brain penetration and high oral bioavailability in rat and demonstrates in vivo efficacy in auditory sensory gating and, in an in vivo model to assess cognitive performance, novel object recognition.