A Phase 3 Study to Assess the Safety and Immunogenicity of High-dose Influenza Vaccine in Adults ≥ 60 years of Age

Overview

Sponsor-declared trial summary

Key facts

Sponsor

Abbott Biologicals B.V.

Participant type

Healthy volunteers

Age range

18-64 years, 65+ years

Gender

Male and Female

Therapeutic area

Diseases [C] - Virus Diseases [C02]

Trial duration

20 Oct 2025 → ongoing

Decision date (initial)

2025-06-17

Transition trial

No

Low-intervention

No

Rare-disease indication

No

Vulnerable population

No

Funding sources

Abbott Biologicals B.V.

Trial design

CTIS Part I — objectives, methods, condition coding

Main objective

Scope: Others, Safety

To demonstrate in adults ≥ 60 years of age the noninferiority of Abbott’s candidate trivalent high-dose (TIV-HD) vaccine with respect to the postvaccination hemagglutination-inhibition (HI) antibody titers compared with Efluelda® 28 days after the first vaccination.

Secondary objectives 4

1. 1. To describe for each vaccination group the induced humoral immunogenicity after the first vaccination and the revaccination as measured by the HI and the virus neutralization (VN) assay.
2. 2. To describe for each vaccination group the induced cell-mediated immunity (CMI) after the first vaccination and the revaccination.
3. 3. To compare for each vaccination group the induced humoral and CMI immunogenicity after revaccination with that after the first vaccination.
4. 4. To compare the reactogenicity and safety of TIV-HD vaccine with that of Efluelda® and Influvac®.

Conditions and MedDRA coding

Influenza immunisation

Regulatory references

Scientific advice from competent authorities

Medicines Evaluation Board, European Medicines Agency

Plan to share IPD

No

Eligibility criteria

Principal inclusion / exclusion criteria as submitted by sponsor

Inclusion criteria 4

1. 1. Willing and able to give informed consent and able to adhere to all protocol-required study procedures.
2. 2. Adults ≥ 60 years of age who are overall healthy in the clinical judgment of the investigator based on the medical history and clinical assessment (including physical examination, vital signs, clinical laboratory tests). Subjects may have underlying illnesses as long as their symptoms/signs are controlled. If on regular prescribed medication for a condition, the medication dose must have been stable for at least 3 months preceding study vaccination.
3. 3. Female subjects must be postmenopausal, defined as female subjects with at least 1 year of absence of menstruation or follicle-stimulating hormone and luteinizing hormone values of ovarian suppression.
4. 4. Ability to comply with study requirements, including the use of an application on a personal device (i.e., smartphone, tablet, etc.) or a provisioned device to record solicited events and other per-protocol required data.

Exclusion criteria 20

1. 1. History of allergy to egg or chicken proteins, or history of any reaction or hypersensitivity to a previous dose of influenza vaccine components.
2. 11. Chronic systemic administration (defined as more than 14 days) of immunosuppressant or immune-modifying medication (such as monoclonal antibodies) for five elimination half-lives or the proposed time in Appendix 16.5, whichever is longer, prior to the first study vaccination or planned use thereof during the study.
3. 12. Receipt of blood or blood products within 3 months preceding enrollment.
4. 13. Being a solid organ or bone marrow/stem cell transplant recipient.
5. 14. Use of cytotoxic drugs, anticancer chemotherapy, or radiation therapy within 36 months before the day of study vaccination.
6. 15. Receipt of another investigational agent within 30 days prior to study vaccination, or planned use during the entire study period.
7. 16. Known drug or alcohol abuse.
8. 17. Planned surgery requiring a general anesthetic, or planned surgery requiring inpatient hospitalization for at least 24 hours during the entire study period.
9. 18. Being an employee of the Sponsor/CRO conducting this study, personnel of the study site or placed in an institution by regulatory or legal ordinance.
10. 19. Any concurrent condition that in the opinion of the investigator would pose a health risk to the subject if enrolled or could interfere with the evaluation of the study vaccine including (but not limited to) bleeding disorder, immunodeficiency, seizure disorder, or acute or progressive hepatic, renal, neurological, neuromuscular, or psychiatric disease.
11. 20. Any other reason that, in the investigator’s opinion, prohibits the inclusion of the subject into the study.
12. 2. History of serious adverse reaction to any influenza vaccine.
13. 3. History of Guillain-Barré syndrome.
14. 4. Laboratory confirmed influenza infection or vaccination against influenza in the 6 months preceding enrollment.
15. 5. Receipt of any vaccine within the preceding 4 weeks of study vaccination or planned vaccination within the 4-week period following each study vaccination.
16. 7. Having fever and/or acute disease or infection on the day of the first study vaccination (enrollment can be deferred for up to 2 weeks, provided the subject remains otherwise eligible). - Fever is defined as body temperature ≥ 38.0°C (measured by oral method). - Subjects with a minor illness (such as mild diarrhea, mild upper respiratory infection) without fever may be enrolled at the discretion of the investigator.
17. 8. Immunocompromising condition or immunosuppressive therapy within 6 months preceding enrollment.
18. 9. Thrombocytopenia or bleeding disorder contraindicating intramuscular vaccination.
19. 10. Chronic use of systemic corticosteroids at a dose ≥ 20 mg/day of prednisone or equivalent for 14 consecutive days or more, prior to the first study vaccination or planned use thereof during the study. Topical use of corticosteroids (e.g., cream, ocular drops, inhalation and intranasal sprays), within the dosage noted on the product label, is allowed.
20. 6. Planned administration of any influenza vaccine (other than the study vaccine) for the entire study period.

Endpoints

Primary and secondary outcome measures (English text)

Primary endpoints 1

1. Postvaccination HI GMTs for each of the three strains 28 days (Day 29) after the first vaccination.

Secondary endpoints 8

1. 1. Postvaccination HI GMTs for each of the three strains after the revaccination.
2. 2. Postvaccination VN GMTs for each of the three strains after the first and the revaccination.
3. 3. Postvaccination HI and VN geometric mean fold increases (GMFIs) and seroconversion rates after the first and the revaccination.
4. 4. Postvaccination reverse cumulative distribution (RCD) curves for HI and VN titers for each of the three strains after the first and the revaccination.
5. 5. Postvaccination CMI values.
6. 6. Unsolicited (i.e., spontaneously reported) AEs within 28 days following each vaccination, including SAEs, AESIs, MAEs, and NCIs.
7. 7. Serious adverse events, AESIs, MAEs, and NCIs from Day 29 to Month 6 postvaccination (first vaccination only).
8. 8. Solicited (i.e., prelisted in subject eDiary) injection site adverse reactions and systemic adverse reactions within 7 days following each vaccination. The following adverse reactions will be assessed (injection site): erythema, swelling, induration, pain, and ecchymosis, and (systemic): fever, headache, fatigue, malaise, myalgia, arthralgia, sweating, and shivering.

Investigational products

Investigational medicinal products (IMPs), comparators, placebo, auxiliary

Test 1

Comparator 2

Sponsors and contacts

Sponsor organisations, regulatory contacts, third parties

Abbott Biologicals B.V.

Sponsor organisation

Abbott Biologicals B.V.

Address

C. J. Van Houtenlaan 36

City

Weesp

Postcode

1381 CP

Country

Netherlands

Scientific contact point

Organisation

Abbott Biologicals B.V.

Contact name

Global Clinical Director

Public contact point

Organisation

Abbott Biologicals B.V.

Contact name

Global Clinical Director

Third parties 4

Locations

5 EU/EEA countries · 45 investigational sites

By country

Investigational sites

Country notifications

Trial-start, recruitment-start, end and early-termination notifications submitted per Member State

Results and documents

Annex IV summary of results, Annex V layperson summary, and all documents registered in CTIS for this trial

Documents 155 files

Public protocol annexes, IB summaries, regulatory submissions and post-authorisation documents registered in CTIS.

Application history

4 submissions — initial application plus substantial / non-substantial modifications