Data from 57 abstracts will highlight Pfizer’s scientific progress targeting infectious diseases, including pneumococcal disease and RSV

Pfizer Inc. (NYSE:PFE) will present data from more than 50 company-sponsored, investigator-sponsored and collaborative research abstracts across its infectious disease pipeline and portfolio at the upcoming IDWeek 2026 congress, held in Washington, D.C., from October 21-24, 2026. Data across 12 oral presentations will showcase the Company’s advancements in the prevention and treatment of infectious diseases.

"At Pfizer, we address some of the most urgent challenges in infectious diseases, delivering vaccines and anti-infective therapies that protect and treat people today while pursuing innovations to expand their impact in the future. Our data at IDWeek 2026 reflects this commitment, with real-world and clinical data across our portfolio as well as important clinical milestones for our next-generation pediatric pneumococcal vaccine candidate and registrational Lyme vaccine candidate. Through these efforts, we are translating scientific advancements into meaningful benefits for communities around the world."

— Annaliesa Anderson, Ph.D., Senior Vice President and Chief Vaccines Officer, Pfizer

Key Highlights of Pfizer’s Presence at IDWeek 2026

Advancing Next-Generation Vaccines Across Infectious Diseases

Late-breaking presentation of immunogenicity, safety, and tolerability data from a Phase 2 study comparing Pfizer’s 25-valent pneumococcal conjugate vaccine candidate (PF-07872412; 25vPnC) with PREVNAR 20^® (Pneumococcal 20-valent Conjugate Vaccine) in healthy infants. Topline results from this study were announced in May 2026. These data support the potential of this next-generation vaccine candidate to broaden pneumococcal coverage while informing its ongoing pediatric Phase 3 program.

(Presentation Title: Immunogenicity of a 25-valent pneumococcal coverage vaccine compared with PCV20 in healthy infants: Evaluating a candidate to improve pneumococcal coverage in a Phase 2 trial)
Safety and immunogenicity data from a Phase 3 study evaluating a single 10-µg dose of Pfizer and BioNTech’s 2025-2026 formula of COMIRNATY^® (COVID-19 Vaccine, mRNA), targeting the LP.8.1 variant of SARS-CoV-2, in children 5-11 years of age at increased risk of severe COVID-19 due to underlying medical conditions. These results further support the safety and robust immunogenicity of the LP.8.1-adapted vaccine in at-risk children.

(Presentation Title: Safety and immunogenicity of LP.8.1-adapted BNT162b2 COVID-19 vaccine in children 5–11 years of age)
Phase 3 results from the VALOR study of PF-07307405 (LB6V) evaluating the efficacy and safety of LB6V, Pfizer and Valneva’s 6-valent OspA-based Lyme disease vaccine candidate, in healthy participants 5 years of age and older living in Lyme disease-endemic regions of North America and Europe. These results build upon the topline readout announced in March 2026; additionally, the European Medicines Agency (EMA) has started the review of the Marketing Authorization Application (MAA) as announced in August 2026. These findings support the potential to provide clinically meaningful antibody-associated protection of LB6V against Lyme disease.

(Presentation Title: Efficacy and safety of the LB6V Lyme disease vaccine candidate: Results from a Phase 3 study in participants ≥5 years of age)

Expanding Evidence of Vaccine Impact in Practice

Real-world retrospective cohort study evaluating the effectiveness of ABRYSVO^®(Respiratory Syncytial Virus Vaccine) vaccination against laboratory-confirmed RSV infection among Veteran Affairs nursing home residents across three RSV seasons. These results are the first available third-season data for this population and further support RSV vaccination in high-risk older adults while providing important insights into sustained vaccine effectiveness.

(Presentation Title: First available vaccine effectiveness of bivalent RSVpreF against laboratory-confirmed RSV infection in nursing home residents through 3 seasons after vaccination — 2025-2026)
Multicenter STREETON study evaluating the real-world effectiveness of maternal ABRYSVO vaccination against RSV-associated hospitalization in infants 6 months of age and younger, following the implementation of a national immunization program in Australia. These findings, which are also published in JAMA Pediatrics, support maternal ABRYSVO vaccination and demonstrate protection across infant age groups, disease severity, maternal vaccination characteristics, and RSV subtypes.

(Presentation Title: Maternal RSVpreF vaccine effectiveness against respiratory syncytial virus (RSV) in hospitalized infants by age, vaccination characteristics, and RSV subtype: A multicenter test-negative design study in Australia, 2025-2026 (STREETON Study))
Retrospective cohort analysis evaluating the effectiveness of PREVNAR 20 against all-invasive pneumococcal disease (all-IPD) due to any serotype and all-cause pneumonia (ACP) among U.S. adults 65 years of age and older, regardless of prior pneumococcal vaccination history. By demonstrating reductions in all-IPD and ACP, these real-world results underscore the substantial public health impact of PREVNAR 20 when implemented in routine vaccination practice for older adults.

(Presentation Title: 20-valent pneumococcal conjugate vaccine: Impact and effectiveness against all-cause outcomes among the general population of US older adults by age group, regardless of prior pneumococcal vaccine history)
Modeling study evaluating long-term immunogenicity following a two-dose series of PENBRAYA^® (Meningococcal Groups A, B, C, W, and Y Vaccine), administered to adolescents at extended intervals. These findings indicate that antibodies against meningococcal strain B (MenB) may persist for up to five years, and could offer prolonged protection for higher-risk adolescents alongside a streamlined vaccination schedule that can potentially improve uptake versus current three- or four-dose recommendations.

(Presentation Title: Long-term seroprotection following two-dose MenABCWY: Modeling supports benefits of extended dosing intervals)

IDWeek Presence Reinforces Pfizer’s Commitment to Addressing the Threat of Infectious Diseases

As infectious diseases remain a persistent cause of illness and death worldwide, Pfizer is focused on generating the evidence needed to bring effective vaccines and anti-infective therapies to as many people as possible. Our data at IDWeek reflect that strategy, concentrating innovation in disease areas with the greatest opportunity to impact public health globally, whether through large at-risk populations, the potential for longer-lasting protection, or both. Highlights include emerging data from late-stage investigational programs advancing next-generation vaccines, new analyses supporting established vaccines as standards of care, real-world evidence that deepens understanding of vaccine effectiveness across diverse populations, and several studies surrounding our current and investigational COVID-19 anti-infective therapies.

Detailed Presentation Information

Information on oral presentations led by Pfizer and its collaborators can be found in the table below. A complete list of presentations is available here.

Title/Abstract Number	Presenter	Date/Time (EDT)	Location
Early trends for invasive pneumococcal disease in children after the introduction of the 20-valent pneumococcal conjugate vaccine	Sheldon Kaplan, MD, Baylor College of Medicine/Texas Children’s Hospital	Oct. 22, 11:15 – 11:30 a.m.	103 AB
Post-acute sequelae following SARS-CoV-2, influenza, and RSV infection among adults in the prospective community-based Project PROTECTS cohort	Avantika Srivastava, MS, City University of New York (CUNY) Institute for Implementation Science in Population Health; Department of Epidemiology and Biostatistics, CUNY School of Public Health and Health Policy	Oct. 22, 2:00 – 2:15 p.m.	103 AB
Efficacy and safety of the LB6V Lyme disease vaccine candidate: Results from a Phase 3 study in participants ≥5 years of age	J.W.R. Hovius, MD, PhD, Amsterdam UMC Multidisciplinary Center for Lyme-borreliosis (AMLC), Amsterdam UMC	Oct. 22, 3:15 – 3:27 p.m.	102 AB
Quantifying lifetime risk of Lyme disease in the United States: A population-based modeling study	Riyadh H. Baksh, MS, Pfizer	Oct. 22, 3:51 – 4:03 p.m.	103 AB
Long-term seroprotection following two-dose MenABCWY: Modeling supports benefits of extended dosing intervals	Jessica Presa, MD, Pfizer	Oct. 22, 4:03 – 4:15 p.m.	102 AB
Improved virologic control in severely immunocompromised (SIC) adults with COVID-19 receiving extended duration Paxlovid therapy	Weihang Bao, PhD, Pfizer	Oct. 23, 3:27 – 3:39 p.m.	201
Prevalence of underlying medical conditions associated with increased risk for severe COVID-19 among children under 5 years of age in the United States	Laura D. Zambrano, PhD, MPH, Pfizer	Oct. 23, 3:51 – 4:03 p.m.	201
Impact of long COVID on medically vulnerable populations: Insights from the expanded ‘Attitudes about COVID and Community Engagement with Patients (ACCEPt)’ survey across 10 countries	Frank Spinelli, MD, Pfizer	Oct. 23, 4:15 – 4:27 p.m.	201
Maternal RSVpreF vaccine effectiveness against respiratory syncytial virus (RSV) in hospitalized infants by age, vaccination characteristics, and RSV subtype: A multicenter test-negative design study in Australia, 2025-2026 (STREETON Study)	Ushma Wadia, MBBS, Wesfarmers Centre for Vaccines and Infectious Diseases, The Kids Research Institute Australia/Fiona Stanley Hospital/Perth Children’s Hospital	Oct. 24, 10:45 – 11:00 a.m.	201
Interim safety of respiratory syncytial virus prefusion F (RSVpreF) vaccine exposure during pregnancy the first two United States vaccination seasons	Ashley Michnick, PharmD, PhD, Harvard Pilgrim Health Care Institute, Harvard Medical School	Oct. 24, 10:30 – 10:42 a.m.	206
First available vaccine effectiveness of bivalent RSVpreF against laboratory-confirmed RSV infection in nursing home residents through 3 seasons after vaccination — 2025-2026	Brigid Wilson, PhD, VA Northeast Ohio Healthcare	Oct. 24, 10:42 – 10:54 a.m.	206
Safety and immunogenicity of LP.8.1-adapted BNT162b2 COVID-19 vaccine in children 5–11 years of age	Philip Ponce, MD, Pfizer	Oct. 24, 11:06 – 11:18 a.m.	206
Immunogenicity of a 25-valent pneumococcal coverage vaccine compared with PCV20 in healthy infants: Evaluating a candidate to improve pneumococcal coverage in a Phase 2 trial	Laurence Flint, MD, MPH, MBA, FAAP, Pfizer	Oct. 24, 11:18 – 11:30 a.m.	206

Prescribing Information for Pfizer Medicines

Please see full Prescribing Information for ABRYSVO^® (Respiratory Syncytial Virus Vaccine) or visit https://abrysvoadult.pfizerpro.com/ and https://abrysvomaternal.pfizerpro.com/.

Please see full Prescribing Information for COMIRNATY^® (COVID-19 Vaccine, mRNA) or visit https://comirnatyhcp.com.

Please see full Prescribing Information for PAXLOVID^® (nirmatrelvir 150 mg tablets; ritonavir 100 mg tablets) or visit https://paxlovid.pfizerpro.com.

Please see full Prescribing Information for PENBRAYA^® (Meningococcal Groups A, B, C, W, and Y Vaccine) or visit https://penbraya.pfizerpro.com/.

Please see full Prescribing Information for PREVNAR 20^® (Pneumococcal 20-valent Conjugate Vaccine) or visit https://prevnar20.pfizerpro.com/.

About Pfizer: Breakthroughs That Change Patients’ Lives

At Pfizer, we apply science and our global resources to bring therapies to people that extend and significantly improve their lives. We strive to set the standard for quality, safety and value in the discovery, development and manufacture of health care products, including innovative medicines and vaccines. Every day, Pfizer colleagues work across developed and emerging markets to advance wellness, prevention, treatments and cures that challenge the most feared diseases of our time. Consistent with our responsibility as one of the world's premier innovative biopharmaceutical companies, we collaborate with health care providers, governments and local communities to support and expand access to reliable, affordable health care around the world. For more than 175 years, we have worked to make a difference for all who rely on us. We routinely post information that may be important to investors on our website at www.Pfizer.com. In addition, to learn more, please visit us on www.Pfizer.com and follow us on X at @Pfizer and @Pfizer_News, LinkedIn, YouTube and like us on Facebook at www.facebook.com/Pfizer/.

Pfizer Disclosure Notice

The information contained in this release is as of October 14, 2026. Pfizer assumes no obligation to update forward-looking statements contained in this release as the result of new information or future events or developments.

This release contains forward-looking information about Pfizer’s infectious disease pipeline, in-line products and product candidates, including their potential benefits, as well as Pfizer’s commitment to addressing the threat of infectious diseases, that involves substantial risks and uncertainties that could cause actual results to differ materially from those expressed or implied by such statements. Risks and uncertainties include, among other things, uncertainties regarding the commercial success of Pfizer’s infectious disease products and product candidates; the uncertainties inherent in research and development, including the ability to meet anticipated clinical endpoints, commencement and/or completion dates for our clinical trials, regulatory submission dates, regulatory approval dates and/or launch dates, as well as the possibility of unfavorable new clinical data and further analyses of existing clinical data; risks associated with initial, preliminary or interim data; the risk that clinical trial data are subject to differing interpretations and assessments by regulatory authorities; whether regulatory authorities will be satisfied with the design of and results from our clinical studies; whether and when any drug applications, biologics license applications and/or emergency use authorization applications may be filed in any jurisdictions for any potential indication for Pfizer’s product candidates; whether and when any such applications that may be pending or filed for any of Pfizer’s product candidates may be approved by regulatory authorities, which will depend on myriad factors, including making a determination as to whether the product's benefits outweigh its known risks and determination of the product's efficacy and, if approved, whether any such product candidates will be commercially successful; decisions by regulatory authorities impacting labeling, manufacturing processes, safety and/or other matters that could affect the availability or commercial potential of Pfizer’s products or product candidates, including development of products or therapies by other companies; manufacturing capabilities or capacity; risks and uncertainties related to changes to vaccine or other healthcare policy in the U.S.; uncertainties regarding the ability to obtain or maintain recommendations from vaccine advisory or technical committees and other public health authorities and uncertainties regarding the commercial impact of any such recommendations, including uncertainties related to the potential impact of narrowing recommended patient populations; challenges related to public vaccine confidence or awareness; risks and uncertainties related to issued or future executive orders or other new, or changes in, laws or regulations; uncertainties regarding the impact of COVID-19 on Pfizer’s business, operations and financial results; and competitive developments.

A further description of risks and uncertainties can be found in Pfizer’s Annual Report on Form 10-K for the fiscal year ended December 31, 2025 and in its subsequent reports on Form 10-Q, including in the sections thereof captioned "Risk Factors" and "Forward-Looking Information and Factors That May Affect Future Results", as well as in its subsequent reports on Form 8-K, all of which are filed with the U.S. Securities and Exchange Commission and available at www.sec.gov and www.pfizer.com.

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