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Today, the US Food and Drug Administration conditionally approved Varenzin-CA1 (molidustat oral suspension), the first drug for the control of non-regenerative anemia associated with chronic kidney disease (CKD) in cats. Non-regenerative anemia can be a fatal condition because the cat’s bone marrow is unable to produce enough red blood cells to replace the older or damaged red blood cells that are naturally removed from the blood, preventing the lungs from carrying oxygen throughout the body. .

CKD is a disease that requires daily management in cats, and non-regenerative anemia is a complication that often contributes to the death or euthanasia of affected cats due to poor quality of life. Cats can develop CKD at any age, but it is often diagnosed in older cats. It can be triggered by other diseases or malformations of the kidneys, bacterial or viral infections, kidney inflammation and associated damage (glomerulonephritis), cancers, or a buildup of protein in the kidneys (amyloidosis). Cats with CKD develop non-regenerative anemia when their kidneys produce less of a hormone called erythropoietin, which helps the bone marrow make red blood cells.

Current available treatments for non-regenerative anemia in cats with CKD include blood transfusions, iron supplementation therapy, and erythropoietin replacement. However, there are no erythropoietin treatments approved for use in cats. Varenzin-CA1 works by helping to increase the production of erythropoietin in the kidney, which in turn stimulates the bone marrow to produce more red blood cells.

“Varenzin-CA1 is the first drug to receive conditional approval for use in cats, providing access to a novel medicine for our feline companions suffering from non-regenerative anemia due to CKD,” said Tracey Forfa, director of the Center for Medicine. FDA Veterinary. “In addition, this is the first drug for cats with expanded conditional approval, a path to market that encourages the development of innovative treatments and increases options for treating animals with rare conditions, serious or life-threatening diseases, or diseases without the existence or adequate therapies.”

Under conditional approval, the FDA has concluded that the drug is safe for its intended purpose and has a reasonable expectation of being effective. This allows cats with the disease to receive the treatment while full effectiveness data is collected. The initial conditional approval is good for one year with the potential for four annual renewals. During this time, the animal drug sponsor must demonstrate active progress to demonstrate substantial evidence of effectiveness for full approval. If a sponsor does not meet the substantial evidence of effectiveness requirements at the five-year mark, the product may no longer be marketed.

Extended Conditional Approval The authority was granted to the FDA in the Animal Drug User Fee Act of 2018 and is for drugs that address a serious or life-threatening disease or condition, or unmet animal or human health need, and for which to demonstrate efficacy would require a complex or particularly difficult study or studies. The expanded conditional approval program will expire in 2028.

The reasonable expectation of effectiveness of Varenzin-CA1 was evaluated in a two-phase study. The first phase involved a multicenter, double-blind, randomized, placebo-controlled field safety and efficacy study. The second phase was an optional, unblinded continuation of the field study. The study enrolled 23 cats from 4 to 17 years of age of various breeds or mixed breeds diagnosed with non-regenerative anemia associated with CKD.

Varenzin-CA1 is a liquid that is given to the cat orally once daily for up to 28 days. Treatment can be repeated as necessary after a minimum break of seven days. Varenzin-CA1 is available only by prescription from a licensed veterinarian as professional expertise is required to properly diagnose CKD and non-regenerative anemia in cats.

Before prescribing the drug, veterinarians should educate cat owners about possible side effects, including vomiting, increased systolic blood pressure, and thromboembolism (blood clots). The FDA encourages cat owners to work with veterinarians to report adverse events or side effects potentially related to the use of any medication, including Varenzin-CA1.

The FDA has granted conditional approval of Varenzin-CA1 to Elanco US Inc.

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The FDA, an agency within the US Department of Health and Human Services, protects public health by ensuring the safety, efficacy, and security of human and veterinary drugs, vaccines, and other biological products for human use. and medical devices. The agency is also responsible for the safety and security of our nation’s food supply, cosmetics, dietary supplements, products that emit electronic radiation, and for regulating our nation’s tobacco products.