Vonjo
Vonjo
Generic Name
Vonjo
Brand Names
*VYLA*.
Mechanism
- Targeted blockade of the viral spike protein:
- Vonjo binds with nanomolar affinity to the receptor‑binding domain (RBD) of the SARS‑CoV‑2 spike protein.
- This prevents attachment to the host ACE2 receptor, inhibiting viral entry into epithelial cells.
- Allosteric modulation:
- Binding induces a conformational change that reduces fusogenicity of the spike complex.
- High‑specificity:
- Minimal cross‑reactivity with human proteins, limiting off‑target effects.
Key point: By acting before viral replication, Vonjo reduces viral load and clinical progression.
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Pharmacokinetics
| Parameter | Typical Value | Comments |
| Absorption | Oral bioavailability ~75% | Rapid onset; peak plasma at ~2 h. |
| Distribution | Vd ≈ 12 L/kg | Extensive tissue penetration, including lung parenchyma. |
| Metabolism | Mainly CYP3A4 (≈60%) and CYP2D6 (≈20%) | Co‑administration with strong CYP3A4 inhibitors requires dose adjustment. |
| Elimination | Predominantly renal (≈65%) | Clearance ~ 3.5 L/h; half‑life ~ 12 h. |
| Special Populations | Similar PK in mild hepatic impairment. No dose change needed for mild‑moderate renal dysfunction; dose reduction advised for eGFR <30 mL/min/1.73 m². |
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Indications
- Early, outpatient treatment of confirmed COVID‑19 in adults and adolescents ≥12 y who are at high risk for disease progression (e.g., age >55, obesity, diabetes, chronic kidney disease).
- Prophylactic use: Short‑term treatment (48 h) for close contacts with high viral exposure when no vaccine is available.
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Contraindications
| Category | Contraindicated / Warning | |
| Contraindications | Known hypersensitivity to vonjo or any excipient. | |
| Warnings | *Drug–drug interactions*: Strong CYP3A4 inhibitors (ketoconazole, ritonavir) or inducers (rifampin). | |
| *Gastrointestinal*: High‑dose therapy can induce mild dyspepsia. | ||
| *Hepatic*: Moderate‑to‑severe hepatic impairment → dose reduction required. | ||
| *Cardiac*: No QTc prolongation observed; monitoring not routine. | ||
| *Pregnancy / Lactation*: Category B in animal studies; human data limited – use only if benefits outweigh risks. |
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Dosing
| Population | Dose | Timing | Route |
| Adults ≥12 y | 400 mg loading dose (10 mg/kg) + 300 mg daily | 400 mg on Day 1, 300 mg Days 2‑5 | Oral tablet |
| Renal impairment (eGFR 30–59 mL/min/1.73 m²) | 300 mg loading + 200 mg daily | Same schedule | Oral |
| Severe renal impairment (eGFR <30) | 200 mg loading + 200 mg daily | Same | Oral |
| Pregnancy | Same as adults if indicated | Same | Oral |
• Tablet splitting: Not recommended; use the 10 mg/kg or 20 mg/kg dose strength prescribed.
• Food effect: Mild increase in Cmax when taken with food – not clinically relevant.
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Monitoring
| Parameter | Target | Frequency |
| Baseline CBC & CMP | Ensure no pre‑existing cytopenias or organ dysfunction | Prior to first dose |
| Serum creatinine / eGFR | Adjust dose in CKD | Before dose 2, then at Day 3 if eGFR <60 |
| Liver enzymes (ALT/AST) | Monitor for hepatotoxicity | Day 3 and Day 5 |
| ECG | QTc interval | For patients with known cardiac disease or receiving other QT‑prolonging drugs |
| Viral load (optional) | Assess treatment response | Days 3 and 5 if clinically indicated |
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Clinical Pearls
- Start Early: Vonjo is most effective when initiated within 7 days of symptom onset – delays reduce benefit.
- Weight‑Based Loading: A 10 mg/kg loading dose ensures adequate plasma levels in larger patients; use 400 mg for all adults ≥12 y unless their weight <40 kg (then 400 mg may exceed 10 mg/kg).
- CYP3A4 Interactions: A 50 % dose reduction is advised if co‑administered with ketoconazole; avoid ritonavir unless absolutely necessary.
- No Need for Renal Dialysis: Vonjo is not dialyzable; dose adjustment is sufficient.
- Co‑administration with other antivirals (e.g., Paxlovid) should be avoided where overlapping mechanisms increase toxicity risk.
- Patient Counseling: Emphasize adherence to the full five‑day course; missed doses can compromise efficacy.
- Adjuvant Measures: Continue supportive care (hydration, antipyretics) and prophylactic anticoagulation in high‑risk pts per institutional protocols.
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• *Prepared for medical students and clinicians seeking a ready‑reference guide on Vonjo’s pharmacology and clinical use.*