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1.
Preprint en Inglés | medRxiv | ID: ppmedrxiv-22276354

RESUMEN

ImportanceCOVID-19 vaccination is recommended during pregnancy for the protection of the mother. Little is known about the immune response to booster vaccinations during pregnancy. ObjectiveTo measure immune responses to COVID-19 primary and booster mRNA vaccination during pregnancy and transplacental antibody transfer to the newborn. DesignProspective cohort study of pregnant participants enrolled from July 2021 to January 2022, with follow up through and up to 12 months after delivery. SettingMulticenter study conducted at 9 academic sites. ParticipantsPregnant participants who received COVID-19 vaccination during pregnancy and their newborns. Exposure(s)Primary or booster COVID-19 mRNA vaccination during pregnancy. Main Outcome(s) and Measure(s)SARS-CoV-2 binding and neutralizing antibody (nAb) titers after primary or booster COVID-19 mRNA vaccination during pregnancy and antibody transfer to the newborn. Immune responses were compared between primary and booster vaccine recipients in maternal sera at delivery and in cord blood, after adjusting for days since last vaccination. ResultsIn this interim analysis, 167 participants received a primary 2-dose series and 73 received a booster dose of mRNA vaccine during pregnancy. Booster vaccination resulted in significantly higher binding and nAb titers, including to the Omicron BA.1 variant, in maternal serum at delivery and cord blood compared to a primary 2-dose series (range 0.55 to 0.88 log10 higher, p<0.0001 for all comparisons). Although levels were significantly lower than to the prototypical D614G variant, nAb to Omicron were present at delivery in 9% (GMT ID50 12.7) of Pfizer and 22% (GMT ID50 14.7) of Moderna recipients, and in 73% (GMT ID50 60.2) of boosted participants (p<0.0001). Transplacental antibody transfer was efficient regardless of vaccination regimen (median transfer ratio range: 1.55-1.77 for binding IgG and 1.00-1.78 for nAb). Conclusions and RelevanceCOVID-19 mRNA vaccination during pregnancy elicited robust immune responses in mothers and efficient transplacental antibody transfer to the newborn. A booster dose during pregnancy significantly increased maternal and cord blood antibody levels, including against Omicron. Findings support continued use of COVID-19 vaccines during pregnancy, including booster doses. Trial Registrationclinical trials.gov; Registration Number: NCT05031468; https://clinicaltrials.gov/ct2/show/NCT05031468 Key PointsO_ST_ABSQuestionC_ST_ABSWhat is the immune response after COVID-19 booster vaccination during pregnancy and how does receipt of a booster dose impact transplacental antibody transfer to the newborn? FindingsReceipt of COVID-19 mRNA vaccines during pregnancy elicited robust binding and neutralizing antibody responses in the mother and in the newborn. Booster vaccination during pregnancy elicited significantly higher antibody levels in mothers at delivery and cord blood than 2-dose vaccination, including against the Omicron BA.1 variant. MeaningCOVID-19 vaccines, especially booster doses, should continue to be strongly recommended during pregnancy.

2.
Preprint en Inglés | medRxiv | ID: ppmedrxiv-22268599

RESUMEN

PurposeWe investigated SARS-CoV-2 mRNA vaccine-induced binding and live-virus neutralizing antibody response in NSCLC patients to the SARS-CoV-2 wild type strain and the emerging Delta and Omicron variants. Methods82 NSCLC patients and 53 healthy adult volunteers who received SARS-CoV-2 mRNA vaccines were included in the study. Blood was collected longitudinally, and SARS-CoV-2-specific binding and live-virus neutralization response to 614D (WT), B.1.617.2 (Delta), B.1.351 (Beta) and B.1.1.529 (Omicron) variants were evaluated by Meso Scale Discovery (MSD) assay and Focus Reduction Neutralization Assay (FRNT) respectively. We determined the longevity and persistence of vaccine-induced antibody response in NSCLC patients. The effect of vaccine-type, age, gender, race and cancer therapy on the antibody response was evaluated. ResultsBinding antibody titer to the mRNA vaccines were lower in the NSCLC patients compared to the healthy volunteers (P=<0.0001). More importantly, NSCLC patients had reduced live-virus neutralizing activity compared to the healthy vaccinees (P=<0.0001). Spike and RBD-specific binding IgG titers peaked after a week following the second vaccine dose and declined after six months (P=<0.001). While patients >70 years had lower IgG titers (P=<0.01), patients receiving either PD-1 monotherapy, chemotherapy or a combination of both did not have a significant impact on the antibody response. Binding antibody titers to the Delta and Beta variants were lower compared to the WT strain (P=<0.0001). Importantly, we observed significantly lower FRNT50 titers to Delta (6-fold), and Omicron (79-fold) variants (P=<0.0001) in NSCLC patients. ConclusionsBinding and live-virus neutralizing antibody titers to SARS-CoV-2 mRNA vaccines in NSCLC patients were lower than the healthy vaccinees, with significantly lower live-virus neutralization of B.1.617.2 (Delta), and more importantly, the B.1.1.529 (Omicron) variant compared to the wild-type strain. These data highlight the concern for cancer patients given the rapid spread of SARS-CoV-2 Omicron variant.

3.
Preprint en Inglés | medRxiv | ID: ppmedrxiv-21267805

RESUMEN

The Omicron variant of SARS-CoV-2 is raising concerns because of its increased transmissibility and potential for reduced susceptibility to antibody neutralization. To assess the potential risk of this variant to existing vaccines, serum samples from mRNA-1273 vaccine recipients were tested for neutralizing activity against Omicron and compared to neutralization titers against D614G and Beta in live virus and pseudovirus assays. Omicron was 41-84-fold less sensitive to neutralization than D614G and 5.3-7.4-fold less sensitive than Beta when assayed with serum samples obtained 4 weeks after 2 standard inoculations with 100 {micro}g mRNA-1273. A 50 {micro}g boost increased Omicron neutralization titers and may substantially reduce the risk of symptomatic vaccine breakthrough infections.

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