Bedinvetmab, an anti-NGF monoclonal antibody, persists up to 34 days in horses, complicating doping control.
Background
Acute and chronic pain management in animals and humans is a significant challenge, with current therapies often having side effects or limited efficacy. Monoclonal antibodies (mAbs) targeting Nerve Growth Factor (NGF) represent a novel, potent therapeutic approach by blocking a key mediator of pain signaling. However, the potential for these long-acting pain-masking agents to be misused in competitive equine sports raises serious welfare and integrity concerns, necessitating a clear understanding of their pharmacokinetic profiles in horses for effective doping control. This study addresses the gap in understanding the elimination kinetics of anti-NGF mAbs in equines.
Study Design
This study investigated the elimination profile of bedinvetmab, a canine anti-NGF monoclonal antibody, in three healthy geldings. Each horse received a single subcutaneous (SC) administration of bedinvetmab (dose not specified in abstract, but implied as a single therapeutic dose). Plasma samples were collected over 34 days post-administration. Bedinvetmab concentrations were quantified using a newly developed generic method involving affinity purification with Protein A magnetic beads, followed by tryptic digestion and identification of a proteotypic peptide via capillary flow high performance liquid chromatography coupled with high resolution tandem mass spectrometry (HPLC-HRMS).
Results
Significant interindividual variability in bedinvetmab plasma concentrations was observed among the three geldings. Maximum plasma concentrations (Cmax) ranged from approximately 0.97 to 6.0 μg/mL and were achieved between 1-2 days post-administration.
Bedinvetmab remained detectable in the plasma of two horses up to the last sampled time point of 34 days, with estimated concentrations of 1.9 and 1.7 μg/mL, respectively. In contrast, the third horse showed a much faster elimination, with bedinvetmab detectable only up to 5 days post-administration, at a concentration of 0.13 μg/mL. Although the precise mechanisms underlying this substantial interindividual variability were not elucidated, these results clearly demonstrate that monoclonal antibodies developed for use in other species can exhibit prolonged systemic exposure and effects in horses.
Key Findings
- Bedinvetmab, a canine anti-NGF mAb, was administered subcutaneously to three geldings.
- Maximum plasma concentrations ranged from 0.97 to 6.0 μg/mL, occurring 1-2 days post-administration.
- Bedinvetmab was detectable for up to 34 days in two horses (1.9 and 1.7 μg/mL).
- In a third horse, bedinvetmab was detectable for only 5 days (0.13 μg/mL).
- Significant interindividual variability in elimination profile was observed.
Why It Matters
This study provides crucial pharmacokinetic data for bedinvetmab in horses, directly impacting equine anti-doping strategies. The prolonged detectability of this anti-NGF mAb, up to 34 days in some individuals, means that a single administration could mask pain for an extended period, potentially compromising animal welfare and fair competition. Effective doping controls must account for this extended elimination profile, requiring sensitive detection methods and potentially longer withdrawal periods than previously assumed for such biologics. This research highlights the need for further studies to understand interindividual variability and establish robust regulatory guidelines for therapeutic mAbs in competitive equine sports, moving towards a usable protocol for detection.
bedinvetmab
monoclonal-antibody
anti-ngf
pain-management
equine
doping-control