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 nucleoside analog compound with targeted antiviral activity against feline coronavirus (FCoV), the pathogen that causes feline infectious peritonitis (FIP) in domestic cats. Its antiviral action is specifically directed at FCoV’s RNA-dependent RNA polymerase, a critical enzyme for viral replication and proliferation in feline host cells. As a structural analog of natural nucleosides, GS-441524 is competitively incorporated into the viral RNA synthesis process by the viral polymerase. Unlike natural nucleosides that enable RNA chain extension, GS-441524 lacks the functional groups required for further chain growth, acting as a potent RNA chain terminator that effectively halts FCoV replication. This inhibition reduces the viral load in the cat’s body, prevents the virus from spreading to healthy cells, and mitigates the severe inflammatory response associated with FIP.
As the main active metabolite of the antiviral prodrug remdesivir, GS-441524 exhibits stable pharmacokinetic properties in mammalian species, with a half-life of 24 hours. This extended half-life ensures that the drug maintains an effective concentration in the cat’s bloodstream and tissues for an extended period, providing sustained antiviral inhibition and reducing the need for frequent dosing. In FIP treatment, GS-441524 acts directly on FCoV-infected cells, suppressing viral replication and allowing the cat’s immune system to recover from the virus-induced immune dysregulation. By restoring the immune system’s ability to fight the virus, GS-441524 facilitates the clearance of FCoV from the body and the resolution of clinical signs associated with FIP.
About Feline Infectious Peritonitis (FIP)
Feline Infectious Peritonitis (FIP) is a severe, systemic, and potentially fatal viral disease exclusive to domestic cats, caused by the mutation of virulent strains of feline coronavirus (FCoV). FCoV is a highly contagious virus that is widespread in cat populations worldwide, with transmission primarily occurring through the fecal-oral route. Infected cats shed the virus in their feces, and susceptible cats become infected by ingesting contaminated material or by contacting contaminated surfaces, food, water, or bedding. The virus can survive on environmental surfaces for extended periods, increasing the risk of transmission in multi-cat settings such as catteries, animal shelters, and multi-cat households.
FIP develops only in cats with a compromised immune system that is unable to control FCoV replication. The majority of FIP cases occur in kittens between 6 and 16 weeks of age, due to their immature immune systems and high exposure rates in breeding environments. Other risk factors include chronic stress, malnutrition, concurrent infections (such as FIV or FeLV), and any condition that suppresses the immune system. In these immunocompromised cats, FCoV undergoes genetic mutations that allow it to escape intestinal mucosal immunity, invade the mononuclear phagocyte system, and spread systemically via the bloodstream. This systemic spread triggers a dysregulated immune response that leads to the characteristic pathological changes and clinical signs of FIP.
Clinically, FIP is classified into two primary forms: effusive (wet) and non-effusive (dry), with some cats presenting with a mixed form. Effusive FIP is the most common form, accounting for approximately 60-70% of cases, and is characterized by the accumulation of a thick, yellowish exudate in the abdominal cavity, thoracic cavity, or both. Clinical signs of wet FIP include progressive abdominal distension, dyspnea, persistent fever unresponsive to antibiotic therapy, lethargy, loss of appetite, and rapid weight loss. Non-effusive FIP is less common and is marked by the formation of granulomatous lesions in one or more organs, including the liver, kidneys, spleen, lungs, lymph nodes, and central nervous system. The clinical signs of dry FIP are variable and depend on the organs affected, but commonly include fever, weight loss, lethargy, jaundice, and organ-specific dysfunction such as kidney failure, respiratory distress, or neurological signs (ataxia, seizures, vision loss).
Diagnosing FIP is challenging due to the non-specific nature of its clinical signs and the lack of a definitive rapid diagnostic test. A presumptive diagnosis is made by combining the cat’s epidemiological history, clinical examination findings, laboratory test results, and imaging studies. Key laboratory abnormalities that support a diagnosis of FIP include elevated total globulin levels, a low albumin-to-globulin ratio, lymphopenia, and elevated liver enzyme levels. For effusive cases, analysis of abdominal or thoracic fluid is a key diagnostic step, with the fluid typically showing high protein content, low nucleated cell count, and the presence of FCoV nucleic acid. Histopathological examination of tissue samples showing characteristic granulomas and FCoV is the gold standard for definitive diagnosis. Currently, there is no universally effective vaccine for FIP, and prevention strategies focus on reducing FCoV exposure, minimizing stress, and supporting immune health in cats through optimal nutrition, regular veterinary care, and proper hygiene.
Application and Dosage of GS-441524
GS-441524 is an antiviral injectable solution used off-label in veterinary medicine for the treatment of feline infectious peritonitis, with proven efficacy in both effusive and non-effusive forms of the disease, including cases with ocular and neurological involvement. The drug is manufactured in China and is available in three packaging sizes (6ml, 8ml, 10ml vials) with two active strengths (20mg, 30mg), providing veterinarians with the flexibility to select the appropriate formulation for each cat based on body weight, treatment needs, and disease severity.
The dosage of GS-441524 is determined by the cat’s body weight and the clinical form of FIP, with higher doses indicated 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. Treatment is typically continued until all clinical signs resolve, viral load is undetectable by molecular testing, and laboratory values return to normal ranges. Veterinary monitoring throughout the treatment period is essential to assess the cat’s response to therapy, adjust the dosage as needed, and monitor for any potential adverse effects.
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
