Dan Gill / New York Times News ServiceSteven St. Peter, the chief executive of Aratana Therapeutics, a pet biotech company, says the pet biotech industry is “ripe for innovation.”

Judging by some of the heavy action in the world of biotechnology, one could easily conclude that the industry is going to the dogs. Or cats, maybe.

There are startups named Nexvet and VetDC, CanFel Therapeutics (as in canine and feline), and even Fetch Pharma.

It’s a new example of pack behavior: Entrepreneurs with pedigrees from companies like Genentech and Amgen are turning their attention to pets. They hope to develop the same kinds of innovative drugs for dogs and cats that have revolutionized the treatment of diseases like cancer and arthritis in people.

“We’ve been drugging ourselves for a long time and more recently we’ve been drugging our kids,” said Oleg Nodelman, an investor in and director of Kindred Biosciences, one of the new companies. “Why shouldn’t our pets have access to medicine?”

They do already, of course. Many of the big pharmaceutical companies have long had veterinary drug divisions.

But the new entrepreneurs say they will be more nimble and do what the big companies are not doing, just as the early human medicine biotech companies did.

The big companies focus more on livestock — edible animals as opposed to petable animals — said Dr. Steven St. Peter, chief executive of Aratana Therapeutics, a pet biotech company. Their offerings for pets are mainly vaccines and treatments for fleas, ticks and worms.

The new companies hope instead to treat diseases like cancer and arthritis.

“I was really a little struck by the fact that the biotechnology industry didn’t really participate in animal health at all,” St. Peter said. “There was this very large industry that was ripe for innovation.”

Investors seem to be biting, spurred in part by the interest generated by the huge initial public offering in early 2013 of Pfizer’s animal drug division, now called Zoetis. Since then both Aratana and Kindred have gone public, along with Phibro, which develops drugs for livestock, and Parnell, which sells both livestock and pet drugs. Funds like Adage Capital, Baupost, Fidelity and Wellington are investors in one or more pet drug companies.

The new companies say the time is right because people increasingly view pets as members of the family and are willing to spend thousands of dollars to treat a sick animal.

If the startups succeed, it might not be too long before established biotech companies form their own animal divisions. At least one company, Sorrento Therapeutics, recently announced it would do this.