What is the recommended dosage of Shingrix (zoster vaccine recombinant) for preventing shingles?

Shingrix (Recombinant Zoster Vaccine) Dosage Recommendations

The recommended dosage of Shingrix for preventing shingles is two doses (0.5 mL each), with the second dose administered 2-6 months after the first dose for immunocompetent adults aged 50 years and older, and 1-2 months apart for immunocompromised individuals. 1

Standard Dosing Schedule

• Immunocompetent adults aged ≥50 years:

  • First dose: 0.5 mL intramuscularly at Month 0
  • Second dose: 0.5 mL intramuscularly at Month 2-6 2, 1

• Immunocompromised adults aged ≥18 years:

  • First dose: 0.5 mL intramuscularly at Month 0
  • Second dose: 0.5 mL intramuscularly at Month 1-2 1

Special Populations

Immunocompromised Patients

For patients with immunocompromising conditions (including those with chronic lymphocytic leukemia, HIV, cancer, autoimmune conditions, or organ transplant recipients), a shortened dosing interval is recommended:

• Two doses administered 1-2 months apart 2, 1
• This accelerated schedule helps ensure protection before potentially starting immunosuppressive treatments 1

Previously Vaccinated with Zostavax (ZVL)

• Patients previously vaccinated with Zostavax should still receive the full two-dose series of Shingrix
• Minimum interval after Zostavax: at least 2 months 1

Importance of Completing the Series

Real-world data shows that approximately 70% of patients complete the two-dose series within 6 months, and 80% complete it within 12 months 3. Completing the full series is crucial as:

• Two-dose effectiveness: 70.1% in real-world studies 4
• Single-dose effectiveness: 56.9% 4

While this effectiveness is lower than the >90% reported in clinical trials 5, it still demonstrates significant protection, particularly when both doses are received.

Administration Notes

• Shingrix must be reconstituted before administration by combining the lyophilized component with the adjuvant suspension
• After reconstitution, administer immediately or store refrigerated and use within 6 hours 1
• Can be administered with other vaccines such as influenza or pneumococcal vaccines 1

Efficacy Considerations

The recombinant zoster vaccine (Shingrix) demonstrates superior efficacy compared to the older live vaccine (Zostavax):

• 97.2% efficacy in adults 50+ years
• 91.3% efficacy in adults 70+ years 1

Key Clinical Pearls

1. Second-dose timing flexibility: While the recommended interval is 2-6 months for immunocompetent adults, evidence suggests that second doses administered beyond 6 months still provide effective protection 4

2. Post-shingles vaccination: There is no need to wait after a shingles episode before receiving Shingrix, as long as the acute episode has completely resolved 1

3. Autoimmune conditions: Shingrix is effective and recommended for patients with autoimmune conditions 1, 6

4. Cardiovascular risk reduction: Vaccination against herpes zoster in patients with inflammatory arthritis may reduce the risk of venous thromboembolic events that can occur 60-90 days after herpes zoster infection 6

By following these dosing recommendations, patients can achieve optimal protection against herpes zoster and its complications, including post-herpetic neuralgia.