FluMist (influenza vaccine, live, intranasal) / AstraZeneca - LARVOL DELTA

Replication in human cells supersedes serum antigenic match for the in vivo efficacy of an A/H1N1pdm09 LAIV virus. (PubMed, NPJ Vaccines) - "For FluMist®/Fluenz live attenuated influenza vaccine (LAIV), efficient virus replication in human nasal epithelial cells (hNEC) is an important factor in vaccine effectiveness (VE). LAIVH1.opt was also found to be more immunogenic in ferrets than LAIVH1.par, generating superior anti-HA and anti-NA antibody responses. We conclude that efficient virus replication can supersede antigenic match for high LAIV efficacy."

Journal • Preclinical • Infectious Disease • Influenza • Respiratory Diseases

Live-attenuated influenza virus vaccine strain with an engineered temperature-sensitive and genetically stable viral polymerase variant. (PubMed, J Virol) - "The only licensed live-attenuated influenza vaccine that has been proven safe and effective is FluMist. In this study, we isolated an attenuated influenza mutant virus with a Lys471 single amino acid substitution in PB1, which displayed a temperature-sensitive and a low-pathogenicity phenotype. By applying the PB1-Lys471 substitution to the vaccine mother strain or the circulating influenza virus using reverse genetic technology, a high-performance and safe live-attenuated vaccine carrying the viral antigens of the vaccine-targeted strain can be developed."

Journal • Infectious Disease • Influenza • Respiratory Diseases

PRISM: Revealing Protective Immunity to Influenza Using Systems Immunology (clinicaltrials.gov) - P4 | N=51 | Completed | Sponsor: Emory University | Recruiting ➔ Completed | Trial completion date: Feb 2027 ➔ Apr 2025 | Trial primary completion date: Feb 2027 ➔ Apr 2025

Trial completion • Trial completion date • Trial primary completion date • Infectious Disease • Influenza • Respiratory Diseases

Ingredient Transparency Required for Identifying Alpha-gal Safe Vaccines (ACAAI 2025) - "For influenza, Flumist should not be recommended, as it contains gelatin. Manufacturers are encouraged to embrace ingredient transparency and collaborate with independent portals to facilitate selection of alpha-gal safe vaccines. This case is one of over 5000 AGS related medication inquiries received by Pill Clarity in 2025."

Infectious Disease • Influenza • Novel Coronavirus Disease • Respiratory Diseases

Antiviral drugs for seasonal influenza for 2025-2026. (PubMed, Med Lett Drugs Ther) - No abstract available

Journal • Infectious Disease • Influenza • Respiratory Diseases

Influenza vaccines for 2025-2026. (PubMed, Med Lett Drugs Ther) - No abstract available

Journal • Hepatitis B • Infectious Disease • Influenza • Novel Coronavirus Disease • Respiratory Diseases • Respiratory Syncytial Virus Infections

Pharmacovigilance-based 12-year post-marketing safety analysis of quadrivalent influenza vaccines in children: a VAERS surveillance study. (PubMed, Front Pediatr) - "We conducted a comprehensive 12-year pharmacovigilance analysis utilizing data from the Vaccine Adverse Event Reporting System (VAERS) for individuals under 18 years receiving six FDA-approved QIVs between 2013 and 2024, representing three distinct platforms: four egg-based inactivated vaccines (Afluria, Fluarix, FluLaval, Fluzone), one cell culture-based inactivated vaccine (Flucelvax), and one live-attenuated intranasal vaccine (FluMist). This pharmacovigilance analysis demonstrates generally favorable safety profiles for pediatric QIVs, with cell culture formulations showing superior safety characteristics. The extremely low absolute risk of Guillain-Barré syndrome supports continued routine pediatric influenza vaccination while highlighting the importance of platform-specific safety monitoring."

Adverse events • Journal • P4 data • Infectious Disease • Influenza • Novel Coronavirus Disease • Pediatrics • Respiratory Diseases

EVax-3: Characterizing the Human Airway Immune Response to FluMist Vaccination (clinicaltrials.gov) - P4 | N=30 | Recruiting | Sponsor: Washington University School of Medicine

New P4 trial • Infectious Disease • Influenza • Respiratory Diseases

Prevention and Control of Seasonal Influenza with Vaccines: Recommendations of the Advisory Committee on Immunization Practices - United States, 2025-26 Influenza Season. (PubMed, MMWR Morb Mortal Wkly Rep) - "Updates for the 2025-26 season include 1) antigenic composition of 2025-26 U.S. seasonal influenza vaccines, 2) Food and Drug Administration (FDA) approval of FluMist (LAIV3) for self-administration or caregiver administration, 3) FDA approval of a change in age indication for Flublok (RIV3) from ≥18 years to ≥9 years, and 4) a new ACIP recommendation that children aged ≤18 years, pregnant women, and all adults receive seasonal influenza vaccines only in single-dose formulations that are free of thimerosal as a preservative. A comprehensive summary of recommendations, including those discussed in this report, as well as previous recommendations concerning topics not addressed in this report and that remain unchanged for the 2025-26 season, is available at Influenza; ACIP Recommendations for Vaccination. Additional background information also is available at Prevention and Control of Seasonal Influenza with Vaccines."

Clinical guideline • Journal • Infectious Disease • Influenza • Respiratory Diseases

Local B-cell immunity and durable memory following live-attenuated influenza intranasal vaccination of humans. (PubMed, bioRxiv) - "An intranasally administered, live-attenuated influenza vaccine designed to stimulate mucosal immunity, FluMist, is the sole intranasal vaccine approved in the United States. These findings have implications for improving influenza vaccines and for mucosal vaccination against other respiratory pathogens. Longitudinal nasopharyngeal sampling reveals local influenza-specific B cell responses following intranasal but not intramuscular vaccination."

Journal • Infectious Disease • Influenza • Respiratory Diseases • CD21 • CD27

Association between tick-bite history and safety of gelatin-containing vaccines: Analysis of a large database of the United States. (PubMed, Ticks Tick Borne Dis) - "Vaccines were classified into two categories: (1) gelatin-containing vaccines (live intranasal influenza [FluMist], varicella, measles/mumps/rubella [MMR], oral typhoid, rabies [RabAvert], and yellow fever vaccines [YF-VAX]) and (2) gelatin-free vaccines...While tick bites are associated with AGS, a history of tick bites is not a contraindication for most gelatin-containing vaccines, including MMR, oral typhoid, rabies, and yellow fever vaccines. Further investigations are warranted to evaluate the safety of intranasal influenza and varicella vaccines in this population."

Journal • Allergy • Immunology • Infectious Disease • Influenza • Measles • Mumps • Respiratory Diseases • Rubella • Varicella Zoster

SmokeyFlu: Woodsmoke Exposure, Influenza Infection, and Nasal Immunity (clinicaltrials.gov) - P4 | N=112 | Suspended | Sponsor: University of North Carolina, Chapel Hill | Trial completion date: Dec 2027 ➔ Dec 2028 | Initiation date: Mar 2025 ➔ Oct 2026 | Not yet recruiting ➔ Suspended | Trial primary completion date: Dec 2027 ➔ Dec 2028

Trial completion date • Trial initiation date • Trial primary completion date • Trial suspension • Infectious Disease • Influenza • Otorhinolaryngology • Respiratory Diseases

Responses to Live Attenuated Influenza Virus (LAIV) in Chronic Obstructive Pulmonary Disease (COPD) (clinicaltrials.gov) - P1 | N=40 | Recruiting | Sponsor: University of North Carolina, Chapel Hill | Trial completion date: Mar 2025 ➔ Mar 2026 | Trial primary completion date: Mar 2025 ➔ Mar 2026

Trial completion date • Trial primary completion date • Chronic Obstructive Pulmonary Disease • Immunology • Infectious Disease • Influenza • Pulmonary Disease • Respiratory Diseases

Disruption of the commensal microbiota impairs the maintenance of antigen specific memory T cells. (IMMUNOLOGY 2025) - "We also found that AB-treated mice failed to maintain lung tissue-resident CD4+ and CD8+ memory T cells generated by immunization with a live-attenuated influenza vaccine (FluMist). Collectively, these finds support the requirement of an intact commensal microbiota for the maintenance of CD4+ memory T cells generated upon infection and vaccination. The mechanisms mediating this effect of the commensal microbiota in memory T cell maintenance are currently under active investigation.Keywords: Cells T Cells; Infections Viral; Processes Memory; Tissues Lung Mucosa"

Clinical • Infectious Disease • Influenza • Respiratory Diseases • CD4 • CD8

Broadly active intranasal influenza vaccine with a nanocomplex particulate adjuvant targeting mast cells and toll-like receptor 9. (PubMed, J Control Release) - "Flumist is the only FDA-approved intranasal influenza vaccine. MP12W-CpG NPs provided similar protection in an influenza challenge model. This study demonstrates the potential of this novel intranasal nanocomplex for vaccination."

Journal • Immunology • Infectious Disease • Inflammation • Influenza • Respiratory Diseases • TLR9

AstraZeneca showcases innovation in infectious disease protection at ESCMID Global 2025 (AstraZeneca Press Release) - "AstraZeneca will share new data across its Vaccines & Immune Therapies portfolio at the 2025 Congress of the European Society of Clinical Microbiology and Infectious Diseases (ESCMID Global 2025) in Vienna, Austria, from 11-15 April 2025. With 13 abstracts, including two oral presentations and two late-breaking poster presentations, the Company will highlight progress in advancing novel immunisations against bacterial and viral infectious diseases and share real-world evidence showing the burden of respiratory viral infections and the continued need for protection."

Clinical data • Preclinical • Bronchiectasis • Infectious Disease • Influenza • Respiratory Diseases

SmokeyFlu: Woodsmoke Exposure, Influenza Infection, and Nasal Immunity (clinicaltrials.gov) - P4 | N=112 | Not yet recruiting | Sponsor: University of North Carolina, Chapel Hill

New P4 trial • Infectious Disease • Influenza • Otorhinolaryngology • Respiratory Diseases

In brief: FluMist influenza vaccine for self-administration. (PubMed, Med Lett Drugs Ther) - No abstract available

Journal • Infectious Disease • Influenza • Respiratory Diseases

PRISM: Revealing Protective Immunity to Influenza Using Systems Immunology (clinicaltrials.gov) - P4 | N=50 | Recruiting | Sponsor: Emory University | Not yet recruiting ➔ Recruiting

Enrollment open • Infectious Disease • Influenza • Respiratory Diseases

An Open Label Study of IgG Fc Glycan Composition in Human Immunity (clinicaltrials.gov) - P1 | N=129 | Terminated | Sponsor: Rockefeller University | Phase classification: P=N/A ➔ P1 | Active, not recruiting ➔ Terminated; Inadequate enrollment

Phase classification • Trial termination

Influenza vaccine for 2024-2025. (PubMed, Med Lett Drugs Ther) - No abstract available

Journal • Hepatitis B • Infectious Disease • Influenza • Respiratory Diseases • Respiratory Syncytial Virus Infections

PRISM: Revealing Protective Immunity to Influenza Using Systems Immunology (clinicaltrials.gov) - P4 | N=50 | Not yet recruiting | Sponsor: Emory University

New P4 trial • Infectious Disease • Influenza • Respiratory Diseases

Responses to Live Attenuated Influenza Virus (LAIV) in Chronic Obstructive Pulmonary Disease (COPD) (clinicaltrials.gov) - P1 | N=40 | Recruiting | Sponsor: University of North Carolina, Chapel Hill | Trial primary completion date: Dec 2024 ➔ Mar 2025 | Trial completion date: Dec 2024 ➔ Mar 2025

Trial completion date • Trial primary completion date • Chronic Obstructive Pulmonary Disease • Immunology • Infectious Disease • Influenza • Pulmonary Disease • Respiratory Diseases • IFNG

VAXXAIR: Vaccine Pandemic Preparedness Through Airway Immunology Characterization (clinicaltrials.gov) - P1 | N=60 | Not yet recruiting | Sponsor: Chronic Obstructive Pulmonary Disease Trial Network, Denmark | Trial completion date: Dec 2025 ➔ Apr 2026 | Initiation date: Jan 2024 ➔ May 2024 | Trial primary completion date: Dec 2025 ➔ Apr 2026

Trial completion date • Trial initiation date • Trial primary completion date • Infectious Disease • Influenza • Respiratory Diseases • CD4 • CD8

Immune Response To Intranasal Influenza Vaccination (clinicaltrials.gov) - P=N/A | N=300 | Active, not recruiting | Sponsor: University of Bergen | Trial completion date: Dec 2022 ➔ Dec 2030 | Trial primary completion date: Dec 2022 ➔ Dec 2025

Trial completion date • Trial primary completion date • Infectious Disease • Influenza • Otorhinolaryngology • Respiratory Diseases