Product Description
| Product Name |
GS-441524 |
| Expiry Date |
1 Year From The Date Of Manufacture |
| Storage Condition |
Room Temperature |
| CAS Number |
1191237-69-0 |
| Core Function |
Treatment For Cat FIP |
| Dosage Form |
Injection |
| Country of Manufacture |
China |
| Packaging Specs |
6ml/vial, 8ml/vial, 10ml/vial |
| Active Strength |
20mg, 30mg |
GS-441524 is a synthetic nucleoside analog that exhibits specific and potent antiviral activity against feline coronavirus (FCoV), the causative agent of feline infectious peritonitis (FIP). Its mechanism of action is based on the selective inhibition of FCoV’s RNA-dependent RNA polymerase, an enzyme that is essential for the virus to replicate its genetic material and produce new viral particles in feline host cells. GS-441524 mimics the structure of natural nucleosides, the building blocks of RNA, and is therefore recognized and utilized by the viral polymerase during RNA synthesis. Once incorporated into the viral RNA chain, it acts as a chain terminator, preventing further elongation of the RNA molecule and effectively halting FCoV replication. This inhibition of viral replication reduces the viral load in the cat’s body and stops the virus from spreading to healthy cells and tissues.
As the primary active metabolite of remdesivir, GS-441524 has a favorable pharmacokinetic profile in mammals, with a half-life of 24 hours. This long half-life ensures that the drug remains active in the cat’s body for an extended period after administration, providing sustained antiviral effect and reducing the frequency of dosing required for effective treatment. In the management of FIP, GS-441524 not only inhibits viral replication but also alleviates the severe inflammatory response that is responsible for the majority of clinical signs and tissue damage in FIP. By reducing viral load and inflammation, GS-441524 allows the cat’s immune system to recover its normal function and mount an effective response to clear the virus, leading to the resolution of clinical signs and improved outcomes for infected cats.
About Feline Infectious Peritonitis (FIP)
Feline Infectious Peritonitis (FIP) is a severe systemic viral disease that affects domestic cats, caused by the mutation of pathogenic strains of feline coronavirus (FCoV). FCoV is a highly prevalent virus in cat populations, with transmission occurring primarily through the fecal-oral route. The virus is shed in the feces of infected cats and can survive on environmental surfaces for several weeks, making it easy to spread in multi-cat environments such as catteries, animal shelters, and households with multiple cats. Direct contact with infected cats and contact with contaminated food bowls, litter boxes, and bedding are the main routes of transmission for susceptible cats.
The development of FIP is closely linked to the cat’s immune status—FIP only occurs in cats with a compromised or immature immune system that is unable to control FCoV replication. Kittens are the most susceptible group, as their immune systems are not fully developed, and they are often exposed to FCoV at a young age in breeding environments. Other risk factors for FIP include chronic stress, malnutrition, concurrent viral or bacterial infections, and underlying health conditions that suppress the immune system. In these immunocompromised cats, FCoV undergoes genetic mutations that allow it to escape intestinal immunity, invade the mononuclear phagocyte system, and spread systemically throughout the body, leading to the development of FIP.
FIP presents in two main clinical forms: effusive (wet) and non-effusive (dry), with each form having distinct pathological and clinical features. Effusive FIP is characterized by the accumulation of a protein-rich exudate in the abdominal cavity, thoracic cavity, or both, which is caused by increased vascular permeability due to the virus-induced inflammatory response. Clinical signs of wet FIP include progressive abdominal distension, difficulty breathing, persistent fever, lethargy, loss of appetite, and weight loss. Non-effusive FIP is characterized by the formation of granulomatous lesions in various organs, including the liver, kidneys, spleen, lungs, and central nervous system. The clinical signs of dry FIP are more variable and depend on the organs affected, but commonly include fever, weight loss, lethargy, jaundice, and organ-specific dysfunction such as kidney failure or neurological signs.
Diagnosing FIP is a significant challenge in veterinary medicine due to the non-specific nature of its clinical signs and the lack of a simple, definitive diagnostic test. Veterinarians typically make a presumptive diagnosis based on a combination of the cat’s history, clinical examination, laboratory tests, and imaging studies. Key laboratory findings that support a diagnosis of FIP include elevated globulin levels, a low albumin-to-globulin ratio, lymphopenia, and elevated liver enzymes. For effusive cases, analysis of abdominal or thoracic fluid is a critical diagnostic step, with the fluid showing high protein content, low cell count, and the presence of FCoV. Molecular testing for FCoV nucleic acid in fluid or tissue samples can also support the diagnosis. At present, there is no effective vaccine for FIP, and prevention focuses on reducing FCoV exposure, minimizing stress, and supporting immune health in cats through optimal nutrition and veterinary care.
Application and Dosage of GS-441524
GS-441524 is an antiviral injectable solution used off-label in veterinary clinical practice for the treatment of feline infectious peritonitis, with demonstrated effectiveness in treating both effusive and non-effusive forms of the disease, including cases with ocular and neurological involvement. The drug is available in three packaging sizes (6ml, 8ml, 10ml vials) and two active strengths (20mg, 30mg), providing veterinarians with flexibility in dosing to meet the needs of individual cats of different weights and treatment requirements.
The dosage of GS-441524 is based on the cat’s body weight and the clinical form of FIP, with higher doses required for cats with dry FIP, ocular/neurological involvement, or recurrent disease. The drug is administered via subcutaneous or intraperitoneal injection, and the treatment course is individualized based on the cat’s clinical response. Most cats require continuous treatment until all clinical signs resolve, viral load is undetectable, and laboratory values return to normal. Veterinary monitoring throughout treatment is essential to assess the cat’s response, adjust the dosage as needed, and ensure the safety and efficacy of the treatment.
Recommended Dosage Regimen:
- FIP (Wet type): 0.3ml/kg of body weight + 0.1ml residue, injectable administration
- FIP (Dry type): 0.4ml/kg of body weight + 0.1ml residue, injectable administration
- FIP with ocular/neurological involvement: 0.5ml/kg of body weight + 0.1ml residue, injectable administration
- Recurrent FIP cases: 0.6ml/kg of body weight + 0.1ml residue, injectable administration
