Home Drug Guide Fostemsavir Tromethamine

Drug Guide

Generic Name

Fostemsavir Tromethamine

Brand Names Rukobia

Classification

Therapeutic: Antiretroviral agent for HIV-1 infection

Pharmacological: Entry inhibitor (gp120 binding inhibitor)

FDA Approved Indications

  • Treatment of HIV-1 infection in heavily treatment-experienced adults with multidrug-resistant HIV-1 infection failing their current antiretroviral regimen

Mechanism of Action

Fostemsavir is a prodrug that is converted into the active moiety, temsavir, which binds directly to the gp120 subunit of the HIV-1 envelope glycoprotein. This prevents the virus from attaching and entering CD4+ T cells, thereby inhibiting viral entry.

Dosage and Administration

Adult: 600 mg twice daily taken with food

Pediatric: Not established

Geriatric: No specific dose adjustment provided, use with caution

Renal Impairment: No specific dose adjustment recommended, but monitor closely

Hepatic Impairment: No specific dose adjustment provided, use with caution

Pharmacokinetics

Absorption: Rapidly absorbed, food increases absorption

Distribution: Wide distribution, binds to plasma proteins

Metabolism: Primarily hepatic via CYP3A enzymes

Excretion: Primarily fecal and urinary pathways

Half Life: Approximately 7 hours

Contraindications

  • Known hypersensitivity to fostemsavir or any component of the formulation

Precautions

  • Use with caution in patients with hepatic impairment, monitor for signs of hepatic toxicity
  • Potential for drug interactions, especially with CYP3A inducers or inhibitors

Adverse Reactions - Common

  • Nausea (≥10%)
  • Headache (≥10%)
  • Fatigue (≥10%)

Adverse Reactions - Serious

  • Liver enzyme elevations (Less common)
  • Hypersensitivity reactions (Rare)
  • Drug interactions leading to virologic failure (Serious but less common)

Drug-Drug Interactions

  • CYP3A inducers (e.g., rifampin, carbamazepine) decrease fostemsavir levels
  • CYP3A inhibitors (e.g., ketoconazole, clarithromycin) increase levels

Drug-Food Interactions

  • No significant interactions reported

Drug-Herb Interactions

  • No formal data, caution advised when combining with herbal supplements

Nursing Implications

Assessment: Monitor for adverse effects, hepatic function, and potential drug interactions

Diagnoses:

  • Risk for infection due to HIV
  • Potential for drug interactions

Implementation: Administer with food, educate patient on importance of adherence and monitoring for adverse effects

Evaluation: Assess virologic response, adverse reactions, and liver function tests periodically

Patient/Family Teaching

  • Take medication with food as directed
  • Report any signs of allergic reactions or severe side effects immediately
  • Maintain regular follow-up appointments for lab monitoring
  • Use contraception if applicable, as directed by provider

Special Considerations

Black Box Warnings:

  • No black box warnings at this time

Genetic Factors: No specific genetic considerations identified

Lab Test Interference: May affect hepatic function tests and viral load assessments

Overdose Management

Signs/Symptoms: Potential for gastrointestinal symptoms, hypersensitivity reactions, or other adverse effects

Treatment: Supportive care, monitor vitals, and provide symptomatic management; no specific antidote

Storage and Handling

Storage: Store at room temperature, 20°C to 25°C (68°F to 77°F)

Stability: Stable for at least 24 months when stored properly

🛡️ 5 Critical Medication Safety Tips for Nurses

1

Triple-Check High-Risk Medications

Always have another nurse verify insulin, heparin, warfarin, and chemotherapy drugs. These "high-alert" medications cause the most serious errors. Check concentration, dose calculation, and pump settings twice.

2

Know Look-Alike, Sound-Alike Drugs

Common mix-ups: hydromorphone/morphine, Celebrex/Celexa, Zyprexa/Zyrtec. Always use BOTH generic and brand names, read labels twice, and use barcode scanning when available. One wrong letter can be fatal.

3

Assess Before AND After Giving Meds

Check vitals before cardiac meds, pain levels before analgesics, and blood glucose before insulin. Always reassess within 30 minutes to evaluate effectiveness and watch for adverse reactions.

4

Watch for Drug Interactions

Common dangerous combinations: warfarin + aspirin (bleeding), ACE inhibitors + potassium (hyperkalemia), digoxin + diuretics (toxicity). Always check drug interactions before administering new medications.

5

Educate Your Patients

Teach patients medication names, purposes, major side effects, and what to report. Informed patients catch errors and improve compliance. Always encourage questions - an educated patient is a safer patient.

⚡ Remember: When in doubt, don't give it out! It's always safer to double-check than regret later.

⚠️ Medical Disclaimer

This drug guide is for educational purposes only and is NOT intended for clinical use. Always consult current prescribing information, healthcare providers, and institutional protocols before administering any medication. Do not use this information for patient care decisions.