(Respiratory Syncytial Virus Vaccine)
Pregnancy Exposure Registry
There is a pregnancy exposure registry that monitors pregnancy outcomes in individuals exposed to ABRYSVO during pregnancy. Individuals who received ABRYSVO during pregnancy are encouraged to contact, or have their healthcare provider contact, 1-800-616-3791 to enroll in or obtain information about the registry.
Risk Summary
All pregnancies have a risk of birth defect, loss, or other adverse outcomes. In the US general population, the estimated background risk of major birth defects and miscarriages in clinically recognized pregnancies is 2% to 4%, and 15% to 20%, respectively, and the estimated background risk of fetal deaths after 20 weeks is 0.6%.
Study 1 enrolled 7,386 pregnant individuals who were randomized 1:1 and received ABRYSVO or placebo (0.5 mL dose, containing the same buffer ingredients in the same quantities as in a single dose of ABRYSVO [see Description (11)]) revealed no evidence for vaccine-associated increase in the risk of congenital anomalies or fetal deaths. Study 2 evaluated 115 pregnant individuals who received ABRYSVO and 117 who received placebo. A numerical imbalance in preterm births in ABRYSVO recipients was observed compared to placebo recipients in these two clinical studies. Available data are insufficient to establish or exclude a causal relationship between preterm birth and ABRYSVO [see Warnings and Precautions (5.2), Adverse Reactions (6.1), Clinical Considerations (8.1), Data (8.1) and Clinical Studies (14.1)].
A developmental toxicity study was performed in female rabbits administered a vaccine formulation containing two times the antigen content of a single human dose of ABRYSVO prior to and during gestation. The study showed no evidence of harm to the fetus or to postnatal survival, growth, or development (see Animal Data).
Maternal Adverse Reactions
In Study 1, 3,698 pregnant individuals received ABRYSVO and 3,687 received placebo. Local and systemic adverse reactions occurred with greater frequency in the ABRYSVO group. Serious adverse reactions observed in pregnant individuals at a higher rate in the ABRYSVO group compared to the placebo group included pre-eclampsia (1.8% versus 1.4%) and gestational hypertension (1.2% versus 1.1%) [see Adverse Reactions (6.1)].
ABRYSVO has not been studied in pregnant individuals less than 24 weeks gestational age, and those at increased risk for preterm birth.
Fetal/Neonatal Adverse Reactions
The infant safety population included 3,659 and 3,646 infants born to individuals in the ABRYSVO or placebo group, respectively. There were 10 (0.3%) fetal deaths in the ABRYSVO group and 9 (0.2%) in the placebo group. Among the infants born to individuals in the ABRYSVO group and in the placebo group, 207 (5.7%) and 172 (4.7%), respectively, were born preterm [see Warnings and Precautions (5.2), Adverse Reactions (6.1) and Clinical Studies (14.1)]. Low birth weight was observed in 5.1% of participants in the ABRYSVO group versus 4.3% in the placebo group, and neonatal jaundice was observed in 7.3% in the ABRYSVO group versus 6.9% in the placebo group. [see Adverse Reactions (6.1)]. For mortality in the neonatal period among infants born to pregnant individuals in Study 1, there were 3 deaths in the ABRYSVO group and 5 in the placebo group, and for overall mortality including after the neonatal period there were 8 deaths in the ABRYSVO group and 14 in the placebo group. Congenital abnormalities were reported in 5.6% in the ABRYSVO group and 6.7% in the placebo group.
Available data are insufficient to establish or exclude a causal relationship between preterm birth and ABRYSVO. To avoid the potential risk of preterm birth with use of ABRYSVO before 32 weeks of gestation, administer ABRYSVO as indicated in pregnant individuals at 32 through 36 weeks gestational age.
Data
Human Data
In Study 1, 3,698 pregnant individuals received ABRYSVO and 3,687 received placebo at 24 through 36 weeks’ gestation. The infant safety population included 3,659 and 3,646 infants born to individuals in the ABRYSVO or placebo group, respectively. Among the infants born to individuals in the ABRYSVO group and in the placebo group, 207 (5.7%) and 172 (4.7%), respectively, had adverse events of preterm birth and 205 (5.6%) and 245 (6.7%), respectively, had reported congenital malformations or anomalies. There were 10 (0.3%) fetal deaths in the ABRYSVO group and 9 (0.2%) in the placebo group.
A pre- and post-natal developmental toxicity study with an embryo-fetal developmental toxicity phase was performed in female New Zealand White rabbits. Rabbits were administered 4 doses by intramuscular injection: at 3 weeks and at 1 week prior to mating, and on gestation days 10 and 24. On each occasion, rabbits received 0.5 mL of a vaccine formulation containing twice the antigen content of F glycoproteins of RSV A and RSV B (120 mcg RSV preF A and 120 mcg RSV preF B), stabilized in prefusion conformation as contained in a single human dose of ABRYSVO [see Description (11)]. No adverse effects on mating, female fertility, or on embryo/fetal or post-natal survival, growth, or development were observed. There were no vaccine-related fetal malformations or variations.
Risk Summary
It is not known whether ABRYSVO is excreted in human milk. Data are not available to assess the effects of ABRYSVO on the breastfed infant or on milk production/excretion. The developmental and health benefits of breastfeeding should be considered along with the mother’s clinical need for ABRYSVO and any potential adverse effects on the breastfed child from ABRYSVO or from the underlying maternal condition. For preventative vaccines, the underlying maternal condition is susceptibility to disease prevented by the vaccine.
The safety and effectiveness of ABRYSVO to prevent RSV LRTD and severe RSV LRTD in infants born to individuals vaccinated at younger than 10 years of age have not been established.
The safety and effectiveness of ABRYSVO to prevent RSV LRTD in non-pregnant individuals younger than 18 years of age via active immunization have not been established.
ABRYSVO is approved for use in individuals 60 years of age and older. In Study 3 and Study 7, of the 18,681 recipients who received ABRYSVO 63% (n=11,695) were aged 60-69 years of age, 32% (n=5,958) were 70-79 years of age and 5% (n=1,027) were ≥80 years of age [see Adverse Reactions (6.1), Use in Specific Populations (8.6), and Clinical Studies (14.2)].
Study 7 Substudy B (NCT05842967) was a Phase 3 single‑arm, open‑label, multicenter study to assess the safety and immunogenicity of ABRYSVO in immunocompromised individuals ≥18 years of age. A total of 203 participants received one dose of ABRYSVO and 201 participants received a second dose of ABRYSVO one month later (an unapproved dosing regimen).
In Study 7, 46% of participants were male, 74% were White, 20% were Black or African American, 4% were Asian, and 5% were Hispanic/Latino. Forty‑seven percent (47%) were 18 through 59 years of age and 53% were ≥60 years of age. The median age of participants was 60 years. In this study, 48% had an autoimmune inflammatory disorder on active immunomodulator therapy, 37% had a history of solid organ transplant on maintenance immunosuppressive therapy, 15% had end‑stage renal disease on hemodialysis, and 3% were on therapy for advanced non‑small cell lung cancer.
Solicited local and systemic reactions that occurred within 7 days following study vaccination were collected. Unsolicited adverse events were collected for 1 month after dose 2 of study vaccination, and serious adverse events were collected for 6 months following dose 2 of study vaccination.
The reactogenicity profile in immunocompromised participants was similar to those observed in other studies [see Adverse Reactions (6.1)], with the following exceptions: Following vaccination with ABRYSVO, pain at the injection site (in up to 46.8% of participants) was the most frequently reported solicited local reaction. The percentages of participants 18 through 59 years of age and ≥60 years of age reporting any solicited local reaction were higher after dose 2 (46.8% and 34.3%, respectively) than dose 1 (26.0% and 19.6%, respectively). There were no severe solicited local reactions. In this study, at least one severe solicited systemic reaction, defined as those preventing daily routine activity (predominantly fatigue as well as headache, muscle pain, and joint pain), was reported in 2.1% and 4.7% of participants 18 through 59 years and ≥60 years of age, respectively, after dose 1 and reported in <1% of participants after dose 2.
One 66 year old participant reported atrial fibrillation and atrial flutter with onset of symptoms 15 days after dose 1. The currently available information on atrial fibrillation and atrial flutter is insufficient to determine a causal relationship to the vaccine [see Adverse Reactions (6.1)].
After a single dose of ABRYSVO, the seroresponse rates [defined as achieving a ≥4‑fold rise in neutralizing titers for RSV A and RSV B from baseline if the baseline measurement is above the lower limit of quantitation (LLOQ) or a post‑vaccination assay result ≥4 × LLOQ if the baseline measurement is below the LLOQ] in the overall study population were 70.2% (95% CI 63.1%, 76.6%) and 71.3% (95% CI 64.2%, 77.6%) for RSV A and RSV B, respectively, 1 month after vaccination. Seroresponse rates in the overall study population did not further increase with a second dose of ABRYSVO 1 month after the first dose [70.2% (95% CI 63.1%, 76.6%) and 71.3% (95% CI 64.2%, 77.6%) for RSV A and RSV B, respectively]. In the subgroup with a history of solid organ transplant, seroresponse rates were 58.2% (95% CI 45.5%, 70.2%) 1 month after the first dose for both RSV A and RSV B, and 65.7% (95% CI 53.1%, 76.8%) and 64.2% (95% CI 51.5%, 75.5%) 1 month after the second dose for RSV A and RSV B, respectively. The data from this study do not establish the effectiveness of ABRYSVO in immunocompromised individuals.
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