Loyal’s experimental drug is an injection designed to be given every three to six months by a veterinarian. The drug is meant to lower levels of a hormone called IGF-1, which is involved in growth and metabolism and has been linked to dog size. Large dogs have a genetic variant that leads to high levels of IGF-1 and small dogs have a different variant that results in lower levels.
Inhibiting this hormone has been shown to increase lifespan in worms, flies, and rodents. In humans, both very high and very low levels increase mortality risk, while a midrange is associated with the lowest mortality.
In early studies, Loyal dosed 130 research dogs with its investigational drug. Halioua says the company has shown that it can reduce IGF-1 levels in large dogs to those seen in medium-size dogs. Two dogs had loose stools for a day or two after receiving the injection, but beyond that, Halioua says, no major side effects have been observed.
To determine the drug’s effect on lifespan, the company is planning a bigger study that will start in 2024 or 2025, and enroll about 1,000 large and giant breed companion dogs that are at least 7 years old. Each will receive either the experimental drug or a placebo.
3:59 PM 01/29/24
