FDA Shows Confidence in Pfizer’s Maternal RSV Shot Ahead of Panel
BIOMARKER
1. Pfizer's investigational vaccine for respiratory syncytial virus (RSV), Abrysvo, has shown safety and effectiveness in the pediatric setting, according to the FDA's briefing document.
2. The FDA's Vaccines and Related Biological Products Advisory Committee (VRBPAC) will meet to evaluate Abrysvo's risk-benefit profile.
3. Pfizer has provided data from five clinical trials, involving over 4,100 mothers, to support Abrysvo's Biologics License Application.
4. Abrysvo demonstrated a vaccine efficacy of 81.1% against severe lower respiratory tract infection (MA-LRTI) through 90 days after birth, and 69.4% by day 180.
5. Mild or moderate adverse reactions were observed in inoculated mothers, with rare serious adverse events, stillbirths, and fetal deaths.
6. Infants receiving Abrysvo showed similar rates of adverse effects as the placebo group, including preterm birth, low birth weight, and developmental delays.
7. Pfizer believes Abrysvo has a favorable benefit/risk profile and can potentially reduce global infant mortality due to RSV.
8. The FDA flagged an imbalance in premature births in one study, with a 1% difference between the Abrysvo and placebo groups.
9. The safety data overall support vaccine administration, with potential uncertainty related to the numerical imbalance in premature deliveries.
10. The VRBPAC will consider this data uncertainty as they vote on the favorable risk analysis of Abrysvo.