CaliciX™ Max is a high-strength systemic antiviral capsule formulated for cats suffering from severe, refractory, or high-viral-load feline calicivirus (FCV) infections, where standard-dose therapy is insufficient.
Each capsule contains: 30 mg of pure EIDD-1931
The active antiviral metabolite of molnupiravir, designed for systemic viral suppression in advanced disease states.
This formulation is intended for use under veterinary supervision in cats requiring higher antiviral exposure due to disease severity, body weight, or poor response to conventional therapy.
Indications & Target ConditionsCaliciX™ Max is designed to support treatment of severe FCV-associated diseases, including:
Severe Oral & Oropharyngeal Disease.
- Severe Feline Chronic Gingivostomatitis (FCGS)
- Caudal Stomatitis with extensive caudal oral inflammation
- Ulcerative Stomatitis unresponsive to dental extractions
- Deep Lingual Ulceration (Viral Glossitis)
- Multifocal Buccal, Labial, and Palatal Ulcers
These conditions are characterized by:
- Extreme oral pain
- Profuse drooling (ptyalism)
- Difficulty eating or swallowing (dysphagia)
- Weight loss and cachexia
- Persistent halitosis and oral bleeding
Systemic & Virulent FCV Disease
CaliciX™ Max may be considered in cases with evidence of high systemic viral burden, including:
Virulent Systemic Feline Calicivirus (VS-FCV)
FCV-associated fever and severe lethargy
Facial or limb edema
Lameness
Pulmonary involvement or pneumonia
Hepatic or pancreatic enzyme elevation
Severe inflammatory response with rapid clinical decline
Refractory or Relapsing Disease
Cats with persistent FCV shedding
Post-extraction FCGS with incomplete response
Chronic stomatitis with repeated relapse after steroids or immunosuppressive therapy
Large or obese cats requiring higher per-dose antiviral exposure
Why High-Strength CaliciX?
CaliciX's EIDD-1931 is the active antiviral form of molnupiravir and demonstrates:
Substantially higher intrinsic antiviral potency than its prodrug
Predictable systemic exposure without reliance on metabolic conversion
Broad activity against RNA viruses, including calicivirus
In severe FCV disease, higher systemic concentrations may be required to:
Rapidly reduce viral replication
Suppress ongoing mucosal and systemic viral injury
Support recovery in cats with advanced inflammation and pain
The 30 mg strength allows veterinarians to achieve these targets with fewer capsules per dose, improving accuracy, compliance, and treatment feasibility.
Designed for Severe Cases & Larger Cats
CaliciX™ Max is particularly suited for:
Cats weighing ≥5 kg with severe disease
Patients requiring 4–6 mg/kg BID dosing
Situations where multiple low-strength capsules would otherwise be required
This strength supports step-up antiviral therapy while maintaining precise dosing control.
Precision Antiviral Therapy, When It matters most CaliciX™ Max represents the highest-potency option in the CaliciX™ antiviral line, offering veterinarians a systemic antiviral tool for the most challenging calicivirus cases.When standard dosing is no longer enough, CaliciX™ Max provides a controlled, high-strength antiviral option designed to support stabilization, recovery, and improved quality of life in cats with severe FCV disease.
CaliciX™ Max – High-Potency EIDD-1931 for Severe Feline Calicivirus Disease
1. Active Ingredient
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EIDD-1931 (β-D-N4-hydroxycytidine) – 30 mg
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Active antiviral metabolite of molnupiravir (EIDD-2801)
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RNA-dependent RNA polymerase (RdRp) mutagenic nucleoside analogue
2. Pharmacological Class
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Direct-acting antiviral (DAA)
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Broad-spectrum RNA virus inhibitor
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Viral error catastrophe inducer
Active Ingredient
- EIDD-1931 (β-D-N4-hydroxycytidine) – 30 mg per capsule
- Pharmacologically equivalent to ~133 mg molnupiravir (EIDD-2801)
3. Mechanism of Action
EIDD-1931 is intracellularly phosphorylated to its active triphosphate form and incorporated into viral RNA during replication. This results in:
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Accumulation of transition mutations
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Loss of viral genome integrity
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Suppression of productive viral replication
This mechanism is host-independent, does not rely on viral proteases, and has a high genetic barrier to resistance.
4. Indications
CaliciX™ Max is intended for use in cats with severe or refractory feline calicivirus (FCV)–associated disease, including:
Severe Oral Disease
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Severe Feline Chronic Gingivostomatitis (FCGS)
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Caudal stomatitis with extensive caudal oral inflammation
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Ulcerative stomatitis unresponsive to dental extractions
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Viral glossitis with deep lingual ulceration
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Multifocal buccal, labial, and palatal ulcers
Systemic & Virulent FCV Disease
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Virulent systemic feline calicivirus (VS-FCV)
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FCV-associated fever and lethargy
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Facial and limb edema
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Lameness
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Pneumonia or respiratory compromise
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Hepatic or pancreatic inflammatory involvement
Refractory / High-Risk Cases
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Post-extraction FCGS with incomplete response
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Persistent FCV shedding
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Relapsing disease following corticosteroids or immunosuppressants
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Large-body-weight cats requiring higher antiviral exposure
5. Clinical Signs Targeted
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Severe oral pain
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Drooling (ptyalism)
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Dysphagia and anorexia
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Oral bleeding and ulceration
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Halitosis
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Weight loss and cachexia
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Fever and systemic inflammation
6. Dosage & Administration
Recommended Systemic Dosing (Veterinary-Directed)
Administration: Oral
Frequency: Twice daily (q12h)
Standard High-Dose Range: 4–6 mg/kg BID
7. Pharmacokinetics
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Good oral bioavailability
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Rapid systemic absorption
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Intracellular activation independent of host viral enzymes
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Distribution into oral mucosa, salivary tissues, and inflamed tissues
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Predictable exposure without reliance on prodrug conversion
Note: Formal feline PK studies for EIDD-1931 are ongoing; dosing is based on translational data and clinical experience.
8. Safety & Precautions
Contraindications
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Pregnancy or breeding animals
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Known hypersensitivity to nucleoside analogues
Use With Caution
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Hepatic impairment
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Renal disease (especially if combined with NSAIDs)
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Long-term use beyond 12 weeks without monitoring
Monitoring Recommendations
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CBC every 2–4 weeks during prolonged therapy
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Liver enzymes (ALT/AST) if combined with other systemic drugs
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Body weight and appetite monitoring
Potential Adverse Effects
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Mild gastrointestinal upset
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Transient lethargy
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Dose-dependent effects with prolonged exposure
9. Drug Interactions
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No known major CYP-mediated interactions
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Compatible with:
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Analgesics (e.g., buprenorphine)
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NSAIDs (with renal monitoring)
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Antibiotics for secondary infection
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Supportive oral care
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10. Regulatory Status
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Not currently licensed for feline use
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Intended for off-label veterinary application under professional supervision
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Use requires informed consent from the animal owner
11. Storage
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Store below 25 °C
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Protect from moisture and light
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Keep in original packaging until use
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