CHMP Recommends Extended H5N1 Vaccine Use for Adults

October 19, 2026 by Lila Morgan

European regulators recommended expanding AstraZeneca’s intranasal H5N1 pandemic flu vaccine to include adults, removing an upper age limit that previously restricted the live attenuated spray to children and adolescents aged 12 months to younger than 18 years.

The Committee for Medicinal Products for Human Use adopted a positive opinion on 15 October 2026. This recommendation proposes changes to the marketing authorization for Pandemic influenza vaccine H5N1 AstraZeneca, according to European Medicines Agency disclosures.

The product, manufactured by AstraZeneca AB, has held conditional EU authorization since May 2016.

Regulatory Evolution of the Intranasal Formula

In the event of an officially declared pandemic, the current H5N1 strain in the formulation would be swapped out for an attenuated version of whatever viral strain is actively circulating. The vaccine carries a live attenuated reassortant strain built on the same structural components as the seasonal nasal spray Fluenz Tetra.

Originally recommended by the CHMP under the name Pandemic influenza vaccine H5N1 MedImmune in March 2016, the vaccine received conditional marketing authorization from the European Commission two months later. That initial approval covered prophylaxis among individuals aged 12 months to under 18.

The authorization covers all European Union member states. The vaccine remains under additional monitoring requirements.

Clinical Data Supporting Adult Authorization

Because regulators note that a new pandemic live attenuated vaccine cannot ethically be tested in children ahead of an actual outbreak, no phase 3 efficacy trial has tested the H5N1 vaccine directly.

Global Regulatory Status and Safety Profile

Licensed H5N1 vaccines in Japan rely instead on inactivated, injectable formulations. Despite its European standing, the vaccine lacks authorization from the US Food and Drug Administration, as well as from regulators across Asia and South America.

European regulators noted that while the live vaccine might slightly increase wheezing in children aged one to two years, that risk remains acceptable during an officially declared pandemic. Reported adverse events commonly include decreased appetite, headache, nasal congestion, and malaise.

Contraindications feature severe allergies to gelatin, gentamicin, or egg proteins. Regulatory guidance allows for administration during a pandemic if emergency medical care is immediately accessible.