Now available in commercial quantities in Australia and New Zealand, Suprelorin, the world's first pet contraceptive, is implanted under the skin between the shoulders to reduce a male dog's testosterone levels to zero and cease reproductive function for six months. Inserted with an implanter similar to those used for microchipping, Suprelorin slowly releases deslorelin, a hormone similar to those used to treat human prostate cancer. The low, continuous dose of deslorelin prevents the produc­tion of sex hormones. The biocompatible implant disappears over time.

Soon pet owners may be able to prevent their male dogs from breeding without castrating them thanks to Suprelorin, a canine birth control implant developed in Australia. "Some male owners, particularly those with 'macho' breeds of dogs, are not keen to castrate their pets," said Dr. Tim Trigg, managing director for Peptech Animal Health (Sydney, Australia), which markets Suprelorin.

"A quick and easy implant gives them a more humane, costeffective choice that leaves their dogs intact but is equally efficacious. The same benefits apply to dogs being shown, of course." In addition to preventing reproduction, the implant treats testosterone related behavioral problems.

It also is approved to treat benign prostatic hyperplasia, a non cancerous enlargement of the prostate gland common in older dogs that have not been neutered.

He said trials showed suprelorin is also effective in controlling populations of elephants, lions, cheetahs, monkeys, dolphins, seals, koalas and kangaroos.

Peptech was the first Australian biotechnology company to take a product from development to Food and Drug Administration approval in the United States with its original animal health product, Ovuplari. "Given our experience, we are positioned perfectly to launch Suprelorin, and I have a very high degree of confi­dence in gaining FDA and European approval," said Mel Bridges, Peptech's executive chairman. At press time, Peptech had met with regulatory authorities in the United States and Europe to start the registra­tion process.