Introduction & Objective: Diabetes is associated with an increased risk for severe COVID-19. A subanalysis of a retrospective observational cohort study was conducted to evaluate the relative vaccine effectiveness (rVE) of 2 previously approved bivalent vaccines that target the ancestral SARS-CoV-2 and the omicron BA.4/BA.5 variant, mRNA-1273.222 (Moderna, Inc.) and BNT162b2 bivalent (Pfizer-BioNTech), in US adults with diabetes. Methods: The study used a US electronic health record dataset (Veradigm) linked with medical claims data of adults aged ≥18 years with ≥1 underlying medical condition associated with increased risk of severe COVID-19 who received a dose of mRNA-1273.222 or BNT162b2 bivalent vaccines between August 31, 2022, and February 28, 2023. The current analysis included a subgroup of individuals with type 1 or type 2 diabetes identified in the dataset by ICD-10 diagnostic code. The rVE was measured against COVID-19-related hospitalizations and COVID-19-related outpatient visits. Follow-up started 7 days after vaccination until May 31, 2023. Propensity score weighting was used to adjust for baseline differences between groups. Results: Of 639,868 individuals with diabetes included in the analysis, 252,635 received mRNA-1273.222, and 387,233 received BNT162b2 bivalent (post-weighting). After weighting, no variables had an SMD >0.1 therefore no adjustments were made to rVE estimates. The adjusted rVEs of mRNA-1273.222 versus BNT162b2 bivalent vaccine against COVID-19-related hospitalizations and outpatient visits were 15.1% (95% CI, 8.7%-21.0%) and 3.7% (95% CI, 1.2%-6.2%), respectively. Conclusion: We found greater effectiveness of mRNA-1273.222 compared with the BNT162b2 bivalent vaccine in preventing COVID-19—related hospitalizations in this cohort of individuals with diabetes. This study emphasizes the importance of assessing COVID-19 vaccine formulations in high-risk adults, including those with diabetes. Disclosure H. Kopel: Employee; Moderna, Inc. Stock/Shareholder; Moderna, Inc. V. Nguyen: Employee; VHN Consulting Inc. Other Relationship; Moderna, Inc. A. Bogdanov: Employee; Veradigm. Other Relationship; Moderna, Inc. I. Winer: Employee; Veradigm. Other Relationship; Moderna, Inc. C. Boileau: Employee; VHN Consulting Inc. Other Relationship; Moderna, Inc. T. Ducruet: Employee; VHN Consulting Inc. Other Relationship; Moderna, Inc. N. Zeng: Employee; Veradigm. Other Relationship; Moderna, Inc. M. Bausch-Jurken: Employee; Moderna, Inc. Stock/Shareholder; Moderna, Inc. D.B. Esposito: Employee; Moderna, Inc. Stock/Shareholder; Moderna, Inc. E. Beck: Employee; Moderna, Inc. Stock/Shareholder; Moderna, Inc. M. Bonafede: Employee; Veradigm. Other Relationship; Moderna, Inc. J.A. Mansi: Employee; Moderna, Inc. Stock/Shareholder; Moderna, Inc.

e23057 Background: Despite the decline in COVID-19–related hospitalizations and mortality during the period of omicron predominance, immunocompromised individuals, including those with cancer, remain at an increased risk for severe COVID-19 outcomes. A subanalysis of a retrospective observational cohort study assessed the relative vaccine effectiveness (rVE) of 2 previously approved bivalent vaccines targeting the ancestral SARS-CoV-2 and the omicron BA.4/BA.5 variant, mRNA-1273.222 (Moderna, Inc., Cambridge, MA, USA) and BNT162b2 bivalent (Pfizer Inc., New York, NY, USA; BioNTech GmbH, Mainz, Germany), in immunocompromised adults in the United States. Methods: The study used a US electronic health record dataset (Veradigm) linked with medical and pharmacy claims data of adults aged ≥18 years with at least 1 underlying medical condition associated with increased risk of severe COVID-19 who received a dose of mRNA-1273.222 or BNT162b2 bivalent vaccines between August 31, 2022, and February 28, 2023. A subgroup analysis was conducted among an immunocompromised population, encompassing cancer patients, organ or stem cell transplant recipients, individuals with primary immunodeficiency, individuals with HIV, and individuals receiving immunosuppressing medications. Comorbid conditions were based on prior medical encounters in the 365 days before vaccination. The outcomes measured were rVE of the two bivalent mRNA vaccines against COVID-19-related hospitalizations (primary outcome) and outpatient visits (secondary outcome). Follow-up started 7 days after vaccination until May 31, 2023 (end of available claims data). Propensity score weighting was used to adjust for baseline differences between groups. Results: The subanalysis included 427,260 immunocompromised individuals, of which 250,573 (58.6%) were identified as having cancer. In the overall weighted immunocompromised population, 169,509 individuals received mRNA-1273.222, and 257,751 received BNT162b2 bivalent. The adjusted rVEs of mRNA-1273.222 versus BNT162b2 bivalent vaccine against COVID-19–related hospitalizations and outpatient visits were 15.0% (95% CI, 7.2%-22.0%; P< 0.001) and 4.8% (95% CI, 1.8%-7.7%; P= 0.002), respectively. Conclusions: In this study, the mRNA-1273.222 vaccine offered greater protection against COVID-19–related hospitalization compared with the BNT162b2 bivalent vaccine among immunocompromised individuals. This study emphasizes the importance of assessing COVID-19 vaccine formulations and optimizing protection, especially in immunocompromised adults, including those with cancer.

Background/Objectives: This retrospective cohort study evaluated the relative vaccine effectiveness (rVE) of two bivalent (original/Omicron BA.4/BA.5) vaccines mRNA-1273.222 versus the BNT162b2 Bivalent in preventing COVID-19-related outcomes in adults with underlying medical conditions associated with increased risk for severe COVID-19. Methods: In a linked electronic health record/claims dataset, US adults (≥18 years) with ≥1 underlying medical condition of interest who received either the bivalent vaccine between 31 August 2022 and 28 February 2023 were identified. The inverse probability of treatment weighting was used to adjust for cohort differences. Cohorts were followed up for COVID-19-related hospitalizations and outpatient encounters until 31 May 2023. Hazard ratios and rVEs were estimated using Cox regression. Subgroup analyses were performed on individuals with pre-specified comorbid conditions. Results: 757,572 mRNA-1273.222 and 1,204,975 BNT162b2 Bivalent recipients were identified. The adjusted rVE over a median follow-up of 198 days was 10.9% (6.2%–15.2%) against COVID-19-related hospitalization and 3.2% (1.7%–4.7%) against COVID-19-related outpatient encounters. rVE estimates for COVID-19 hospitalizations among subgroups with comorbid conditions were as follows: diabetes 15.1% (8.7%–21.0%), cerebro- and cardiovascular disease 14.7% (9.0%–20.1%), chronic lung disease 11.9% (5.1%–18.2%), immunocompromised 15.0% (7.2%–22.2%), chronic kidney disease 8.4% (0.5%–15.7%). Conclusions: Overall, among adults with underlying medical conditions, mRNA-1273.222 was more effective than BNT162b2 Bivalent, especially in preventing COVID-19-related hospitalizations.

Background The emergence of Omicron variants coincided with declining vaccine-induced protection against SARS-CoV-2 infection and other COVID-19-related outcomes. Two bivalent mRNA vaccines, mRNA-1273.222 (Moderna) and BNT162b2 Bivalent (Pfizer-BioNTech) were developed to provide greater protection against the predominate circulating variants by including the mRNA that encodes both the ancestral (original) strain and BA.4/BA.5. We estimated their relative vaccine effectiveness (rVE) in preventing COVID-19-related outcomes in the US.Methods We conducted a retrospective cohort study using a US nationwide dataset linking primary care electronic health records (EHR) and pharmacy/medical claims data. The adult study population (aged ≥18 years) received either mRNA-1273.222 or BNT162b2 Bivalent vaccination between August 31, 2022, and February 28, 2023. We used a propensity score weighting based on the inverse probability of treatment to adjust for the baseline differences in age, sex, race, ethnicity, geographic region, vaccination week, and health status between groups. Outcomes evaluated were rVE of the two bivalent mRNA vaccines against COVID-19-related hospitalizations (primary outcome) and outpatient visits (secondary). We weighted the vaccine groups prior to analysis and estimated adjusted hazard ratios (HR) using multivariable Cox regression models. We calculated rVE as (1−HR) × 100.Results We evaluated outcomes for 1,034,538 mRNA-1273.222 and 1,670,666 BNT162b2 Bivalent vaccine recipients. The adjusted rVE of mRNA-1273.222 versus BNT162b2 Bivalent vaccines against COVID-19-related hospitalization was 9.8% (95% confidence interval: 2.6%–16.4%). The adjusted rVE against COVID-19-related outpatient visits was 5.1% (95% CI: 3.2%–6.9%). When evaluated by age group, the incremental relative effectiveness was greater. Among adults ≥ 65, rVE against COVID-19-related hospitalizations and outpatient visits was 13.5% (95% CI: 5.5%–20.8%) and 10.7% (8.2%–13.1%), respectively.Conclusion We found greater effectiveness of mRNA-1273.222 compared with the BNT162b2 Bivalent vaccine in preventing COVID-19-related hospitalizations and outpatient visits, with increased benefits in older adults.### Competing Interest StatementAlthough not remunerated for work on this study, SHV has received a prior speaker honorarium from Moderna, Inc. SG received honorarium or consulted for Moderna, Pfizer, Seqirus, GlaxoSmithKline, Novavax, Janssen, Vaxart, Icosavax, and Reviral. Grants from Pfizer, Sanofi, Genentech, CDC, NIH. HK, DE, DM, AR, NVV and JAM are employees of Moderna, Inc. and may hold stock/stock options in the company. AB, NZ, IW, and MB work for Veradigm, VHN, CB, and TD are employees of VHN Consulting. Both companies were contracted by Moderna and received fees for data management and statistical analyses. ### Funding StatementThis work was supported by Moderna Inc.### Author DeclarationsI confirm all relevant ethical guidelines have been followed, and any necessary IRB and/or ethics committee approvals have been obtained.YesThe details of the IRB/oversight body that provided approval or exemption for the research described are given below:The retrospective observational study was designed, implemented, and reported in accordance with Good Pharmacoepidemiological Practice, applicable local regulations, and the ethical principles laid down in the Declaration of Helsinki. Approval by an institutional review board and patient consent were not necessary as the study was a noninterventional, retrospective cohort using a certified HIPAA-compliant deidentified research databaseI confirm that all necessary patient/participant consent has been obtained and the appropriate institutional forms have been archived, and that any patient/participant/sample identifiers included were not known to anyone (e.g., hospital staff, patients or participants themselves) outside the research group so cannot be used to identify individuals.YesI understand that all clinical trials and any other prospective interventional studies must be registered with an ICMJE-approved registry, such as ClinicalTrials.gov. I confirm that any such study reported in the manuscript has been registered and the trial registration ID is provided (note: if posting a prospective study registered retrospectively, please provide a statement in the trial ID field explaining why the study was not registered in advance).YesI have followed all appropriate research reporting guidelines, such as any relevant EQUATOR Network research reporting checklist(s) and other pertinent material, if applicable.YesIndividual-level data reported in this study are not publicly shared. Upon request, and subject to review, Veradigm may provide the de-identified aggregate-level data that support the findings of this study. Deidentified data (including participant data as applicable) may be shared upon approval of an analysis proposal and a signed data access agreement. Individual-level data reported in this study shared fully with regulatory agencies.

The emergence of Omicron variants coincided with declining vaccine-induced protection against SARS-CoV-2. Two bivalent mRNA vaccines, mRNA-1273.222 (Moderna) and BNT162b2 Bivalent (Pfizer-BioNTech), were developed to provide greater protection against the predominate circulating variants by including mRNA that encodes both the ancestral (original) strain and BA.4/BA.5. We estimated their relative vaccine effectiveness (rVE) in preventing COVID-19-related outcomes in the US using a nationwide dataset linking primary care electronic health records and pharmacy/medical claims data. The study population (aged ≥18 years) received either vaccine between 31 August 2022 and 28 February 2023. We used propensity score weighting to adjust for baseline differences between groups. We estimated the rVE against COVID-19-related hospitalizations (primary outcome) and outpatient visits (secondary) for 1,034,538 mRNA-1273.222 and 1,670,666 BNT162b2 Bivalent vaccine recipients, with an adjusted rVE of 9.8% (95% confidence interval: 2.6–16.4%) and 5.1% (95% CI: 3.2–6.9%), respectively, for mRNA-1273.222 versus BNT162b2 Bivalent. The incremental relative effectiveness was greater among adults ≥ 65; the rVE against COVID-19-related hospitalizations and outpatient visits in these patients was 13.5% (95% CI: 5.5–20.8%) and 10.7% (8.2–13.1%), respectively. Overall, we found greater effectiveness of mRNA-1273.222 compared with the BNT162b2 Bivalent vaccine in preventing COVID-19-related hospitalizations and outpatient visits, with increased benefits in older adults.

Abstract Background Older age ( > 65 years) and underlying chronic medical conditions are risk factors associated with severe COVID-19 outcomes. In this study, we evaluated the relative vaccine effectiveness (rVE) of a primary series of mRNA-1273 (2 doses) versus BNT162b2 (2 doses) or Ad26.COV2.S (1 dose) and rVE of monovalent mRNA boosters - against medically attended (outpatient and hospitalizations cases), outpatient, and hospitalization cases due to COVID-19 in adults ≥ 18 years with at least one underlying medical condition and by age groups. Methods Data from a U.S. electronic health records system linked with medical claims data were used to evaluate rVE in patients with at least one underlying medical condition (such as immunosuppression, diabetes, chronic lung diseases, cardiovascular diseases, and renal diseases). Part 1 of the study evaluated the rVE of the primary series (February to October 2021), and Part 2 evaluated the rVE of a single monovalent mRNA booster dose (October 2021 to January 2022). Individuals were matched by sex, geographic region, age group, and race. Results In Part 1, mRNA-1273 prevented more medically-attended COVID-19 cases than BNT162b2 and Ad26.COV2.S, with rVEs of 24% (95% confidence interval [CI]: 22–25%) and 51% (49–52%), respectively. Similarly, mRNA-1273 also prevented more outpatient and hospitalized COVID-19 cases than the two comparator vaccines (Table 1). Findings were consistent across age groups. In Part 2, rVE of mRNA-1273 vs. BNT162b2 against medically-attended COVID-19 cases was 14% (95% CI: 9-19%). Importantly, following a booster dose, mRNA-1273 prevented more hospitalizations than BNT162b2 with an rVE of 22% (95% CI: 3–37%) in the overall study population and increased with age, with estimates of 32% (13–47%) and 46% (19–65%) in adults ≥ 50 years and ≥ 65 years, respectively. Conclusion In this study, a primary series of mRNA-1273 was more effective than BNT162b2 or Ad26.COV2.S in preventing medically-attended COVID-19 in individuals at higher risk for severe COVID-19 outcomes. Moreover, a booster dose of mRNA-1273 was more effective compared with BNT162b2, with additional significant benefits against COVID-19-related hospitalizations in older adults. Disclosures Van Hung Nguyen, MPH, Moderna, Inc.: Advisor/Consultant|VHN Consulting Inc.: Salary Catherine Boileau, PhD, Moderna, Inc.: Advisor/Consultant|VHN Consulting Inc.: Salary Alina Bogdanov, MA, Moderna, Inc.: Advisor/Consultant|Veradigm: Salary Ni Zeng, PhD, Moderna, Inc.: Advisor/Consultant|Veradigm: Salary Mac Bonafede, PhD, Moderna, Inc.: Advisor/Consultant|Veradigm: Salary Thierry Ducruet, MSc, Moderna, Inc.: Advisor/Consultant|VHN Consulting Inc.: Salary Andrew M. Rosen, PhD, Moderna, Inc.: Salary|Moderna, Inc.: Stocks/Bonds David Martin, MD, MPH, Moderna, Inc.: Salary|Moderna, Inc.: Stocks/Bonds Daina Esposito, PhD, MPH, Moderna, Inc.: Salary|Moderna, Inc.: Stocks/Bonds Nicolas Van de Velde, PhD, Moderna, Inc.: Salary|Moderna, Inc.: Stocks/Bonds Hagit Kopel, PhD, Moderna, Inc.: Salary|Moderna, Inc.: Stocks/Bonds James Mansi, Moderna, Inc.: Salary|Moderna, Inc.: Stocks/Bonds

Background Few head-to-head comparisons have been performed on the real-world effectiveness of coronavirus disease 2019 (COVID-19) booster vaccines. We evaluated the relative effectiveness (rVE) of a primary series of mRNA-1273 vs BNT162b2 and Ad26.COV2.S and a homologous mRNA booster against any medically attended, outpatient, and hospitalized COVID-19. Methods A data set linking primary care electronic medical records with medical claims data was used for this retrospective cohort study of US patients age & GE;18 years vaccinated with a primary series between February and October 2021 (Part 1) and a homologous mRNA booster between October 2021 and January 2022 (Part 2). Adjusted hazard ratios (HRs) were derived from 1:1 matching adjusted across potential covariates. rVE was (1 - HRadjusted) x 100. Additional analysis was performed across regions and age groups. Results Following adjustment, Part 1 rVE for mRNA-1273 vs BNT162b2 was 23% (95% CI, 22%-25%), 23% (95% CI, 22%-25%), and 19% (95% CI, 14%-24%), while the rVE for mRNA-1273 vs Ad26.COV2.S was 50% (95% CI, 48%-51%), 50% (95% CI, 48%-52%), and 57% (95% CI, 53%-61%) against any medically attended, outpatient, and hospitalized COVID-19, respectively. The adjusted rVE in Part 2 for mRNA-1273 vs BNT162b2 was 14% (95% CI, 10%-18%), 13% (95% CI, 8%-17%), and 19% (95% CI, 1%-34%) against any medically attended, outpatient, and hospitalized COVID-19, respectively. rVE against medically attended COVID-19 was higher in adults age & GE;65 years (35%; 95% CI, 24%-47%) than in those age 18-64 years (13%; 95% CI, 9%-17%) after the booster. Conclusions In this study, mRNA-1273 was more effective than BNT162b2 or Ad26.COV2.S following a primary series during the Delta-dominant period and more effective than BNT162b2 as a booster during the Omicron-dominant period.

Abstract Background Higher rates of influenza-related morbidity and mortality occur in individuals with underlying medical conditions. To improve vaccine effectiveness, cell-based technology for influenza vaccine manufacturing has been developed. Cell-derived inactivated quadrivalent influenza vaccines (cIIV4) may improve protection in seasons in which egg-propagated influenza viruses undergo mutations that affect antigenicity. This study aimed to estimate the relative vaccine effectiveness (rVE) of cIIV4 versus egg-derived inactivated quadrivalent influenza vaccines (eIIV4) in preventing influenza-related medical encounters in individuals with underlying medical conditions putting them at high risk of influenza complications during the 2018–2019 US influenza season. Methods An integrated dataset, linking primary care electronic medical records with claims data, was used to conduct a retrospective cohort study among individuals aged ≥4 years, with ≥1 health condition, vaccinated with cIIV4 or eIIV4 during the 2018–2019 season. Adjusted odds ratios (ORs) were derived using a doubly robust inverse probability of treatment-weighting (IPTW) model, adjusting for age, sex, race, ethnicity, geographic region, vaccination week, and health status. Relative vaccine effectiveness was estimated by (1 − OR) × 100 and presented with 95% confidence intervals (CIs). Results The study cohort included 471 301 cIIV4 and 1 641 915 eIIV4 recipients. Compared with eIIV4, cIIV4 prevented significantly more influenza-related medical encounters among individuals with ≥1 health condition (rVE, 13.4% [95% CI, 11.4%–15.4%]), chronic pulmonary disease (rVE, 18.7% [95% CI, 16.0%–21.3%]), and rheumatic disease (rVE, 11.8% [95% CI, 3.6%–19.3%]). Conclusions Our findings support the use of cIIV4 in individuals ≥4 years of age at high risk of influenza complications and provide further evidence supporting improved effectiveness of cIIV4 compared with eIIV4.

MF59®-adjuvanted trivalent inactivated influenza vaccine (aIIV3) and high-dose trivalent inactivated influenza vaccine (HD-IIV3) elicit an enhanced immune response in older adults compared to standard, quadrivalent inactivated influenza vaccines (IIV4). We sought to determine the relative vaccine effectiveness (rVE) of aIIV3 versus IIV4 and HD-IIV3 in preventing influenza-related medical encounters in this retrospective cohort study involving adults ≥65 years with ≥1 health condition during the 2017–2018 and 2018–2019 influenza seasons. Data were obtained from primary and specialty care electronic medical records linked with pharmacy and medical claims. Adjusted odds ratios (OR) were derived from an inverse probability of treatment-weighted sample adjusted for age, sex, race, ethnicity, geographic region, vaccination week, and health status. rVE was determined using the formula (% rVE = 1 − ORadjusted) × 100. Analysis sets included 1,755,420 individuals for the 2017–2018 season and 2,055,012 for the 2018–2019 season. Compared to IIV4, aIIV3 was 7.1% (95% confidence interval 3.3–10.8) and 20.4% (16.2–24.4) more effective at preventing influenza-related medical encounters in the 2017–2018 and 2018–2019 seasons, respectively. Comparable effectiveness was observed with HD-IIV3 across both seasons. Our results support improved effectiveness of aIIV3 vs IIV4 in a vulnerable population of older adults at high risk of influenza and its complications.