Felycin®-CA1 (sirolimus delayed-release tablets) Redefines Feline Cardiac Care

First-in-class oral management option for hypertrophic cardiomyopathy earns FDA conditional approval, changing the landscape of feline medicine

PENSACOLA, Fla., June 12, 2025 /PRNewswire/ -- Pegasus Laboratories/PRN Pharmacal has announced the addition of a new FDA conditionally approved drug, Felycin^®-CA1 (sirolimus delayed-release tablets), to their portfolio. This first-in-class therapy is designed to manage ventricular hypertrophy in cats with subclinical hypertrophic cardiomyopathy (HCM), representing a major milestone in feline medicine and offering new hope to owners of cats living with this progressive and often fatal disease.

HCM is a heart condition which causes the muscular walls of a cat's heart to become abnormally thick, reducing the heart's ability to pump blood efficiently. This can lead to heart failure and other complications, including sudden death. Many cats with HCM remain subclinical for years, while others may develop symptoms of congestive heart failure.

While the exact cause of the disease is not fully understood, HCM is more common in certain breeds, including British Shorthair, Chartreux, Maine Coon, Persian, Ragdoll, and Sphynx cats. Researchers have also identified mutations in various cardiac genes causing HCM in several of these breeds.

"Felycin-CA1 signals a turning point in feline medicine by providing veterinarians a much-needed option to help slow the progression of HCM beyond just managing the disease," said Dr. Heather Davis, DVM, PhD, DACVS-LA, Director of Clinical Affairs and Veterinary Services at Pegasus Laboratories. "It is a major step forward for cats and the people who care for them. For the first time, we're changing the conversation around what's possible in feline heart care."

FDA conditional approval of Felycin^®-CA1 follows results from a multi-center study demonstrating its ability to improve key cardiac outcomes, while also proving its ease of use in everyday veterinary practices.

"Veterinarians have long-needed options beyond palliative care when it comes to feline HCM," said Dr. Joshua Stern, DVM, PhD, DACVIM. "With Felycin-CA1, we can offer a therapy that has been shown in our initial clinical trial to stop progressive heart muscle thickening, slowing disease progression. We believe this management option marks the beginning of a new chapter where innovation in feline therapeutics becomes the rule, not the exception."

Felycin^®-CA1 is slated to be available beginning August 2025, in 0.4 mg, 1.2 mg, and 2.4 mg tablet strengths by prescription from a licensed veterinarian. Cats should be screened for pre-existing liver disease before starting the medication, and it should not be used in cats with pre-existing liver disease or diabetes mellitus.

About Pegasus Laboratories

Pegasus Laboratories, Inc., based in Pensacola Florida, is a pharmaceutical development and manufacturing organization focused on innovative products to treat chronic conditions in cats, dogs, and horses. Our products go to market under the PRN® Pharmacal brand. We also serve as a contract manufacturer for the Animal Health industry.  We were founded in 1985 and acquired by PBI-Gordon Companies, Inc. in 1999.

SOURCE Pegasus/PRN Pharmacal