Fuzeon 90 mg Injection

**Fuzeon (Enfuvirtide) Overview:**

**Classification:**
– **Type:** HIV Fusion Inhibitor (Entry Inhibitor)
– **Use:** Antiretroviral combination therapy for HIV-1 infection

**Mechanism of Action:**
– Enfuvirtide disrupts the fusion of the HIV-1 virus with CD4+ host cells by targeting **gp41**, a transmembrane protein vital for the virus’s fusion mechanism.
– By binding to **gp41**, enfuvirtide prevents the formation of an entry pore, halting the virus from injecting its genetic material into the host cell.

**Warnings and Precautions**
1. **Injection Site Reactions (ISRs):**
– Almost all patients (98%) report ISRs, such as pain, redness, nodules, and bruising.
2. **Biojector® 2000 Use:**
– Increased risks of neuralgia, bruising, hematomas, and bleeding (not recommended for patients on anticoagulants or with coagulation disorders).
3. **Pneumonia Risk:**
– Monitor for symptoms, particularly in patients with low CD4 counts or other predispositions.
4. **Hypersensitivity Reactions:**
– Discontinue immediately if signs of systemic hypersensitivity (rash, fever, respiratory symptoms) occur.
5. **Immune Reconstitution Syndrome:**
– Potential emergence of inflammatory conditions when immune function improves during combination therapy.

### **Common Side Effects**
– Local ISRs (e.g., pain, erythema)
– Diarrhea
– Nausea
– Fatigue

**Severe Adverse Reactions:**
– Rare hypersensitivity reactions
– Possible pneumonia

### **Drug Interactions**
– No dose adjustment required when combined with other antiretrovirals or non-antiretroviral drugs.

### **Use in Specific Populations**
1. **Pregnancy:**
– No evidence of fetal harm in animal studies; use only if necessary.
2. **Breastfeeding:**
– Avoid due to potential HIV transmission via breast milk.
3. **Pediatric Use:**
– Not established for children <6 years. Limited efficacy and safety data for those ≥6 years.
4. **Geriatric Use:**
– Insufficient data for patients aged ≥65 years.