Booster dose of SARS-CoV-2 vaccine to patients with suboptimal response to previous doses.

REVACCINATION OF IMMUNOSUPPRESSED PATIENTS WITH POOR/NO SARS-COV-2 VACCINE RESPONSE.

Status

Active, not recruiting

Phases

Phase 4

Study type

Interventional

Source

EU CTR

Registry ID

EUCTR2021-003618-37-NO

Enrollment

11000

Registered

2021-06-28

Start date

2021-06-30

Completion date

Unknown

Last updated

2025-09-15

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Patients with immune deficiency without proper response to previous SARS-CoV-2 vaccine doses. MedDRA version: 20.0 Level: HLGT Classification code 10003816 Term: Autoimmune disorders System Organ Class: 10021428 - Immune system disorders MedDRA version: 20.0 Level: PT Classification code 10074555 Term: Transplantation complication System Organ Class: 10022117 - Injury, poisoning and procedural complications MedDRA version: 20.0 Level: HLT Classification code 10003921 Term: B-cell unclassifiab

Interventions

Trade Name: Comirnaty Product Name: SARS-CoV-2 mRNA Pharmaceutical Form: Concentrate for dispersion for injection Trade Name: Spikevax Product Name: SARS-CoV-2 mRNA Pharmaceutical Form: Concentrate a

Eligibility

Sex/Gender

All

Inclusion criteria

Inclusion criteria: • Patients already included in one of the following ongoing vaccine observational subprotocols: • SARS-CoV-2 cellular and humoral immune response following vaccination of kidney transplant recipients and healthy controls • SARS-CoV-2 serological vaccine response in patients at Oslo University Hospital • Vaccine responses in MS: Nevrovax. • A Norwegian study of vaccine response to COVID-19 vaccines in patients using immunosuppressive medication within rheumatology and gastroenterology – The Nor-vaC study • Immunological response to Covid-19 vaccination in Lymphoma patients treated with Rituximab and in Bone marrow Transplanted patients. • Patients with an interval between the first and second vaccine dose according to drug label; 3 weeks for Comirnaty and 4 weeks for SpikeVax. • Patients with no or impaired humoral immune response more than 3 weeks after two doses of SARS-CoV-2 mRNA vaccine (SARS-CoV-2 SPIKE IgG =100 AU). • Available for vaccination at a few centralized centers (OUS, AHUS, Diakonhjemmet Hospital, HUS). • Not participating in therapeutical intervention studies. • Adult patients (=18 years). • For fourth dose: Solid organ transplant recipients with no or impaired humoral immune response 4 weeks after three doses of SARS-CoV-2 mRNA vaccine (SARS-CoV-2 SPIKE IgG =100 AU). Are the trial subjects under 18? no Number of subjects for this age range: F.1.2 Adults (18-64 years) yes F.1.2.1 Number of subjects for this age range 6500 F.1.3 Elderly (>=65 years) yes F.1.3.1 Number of subjects for this age range 4500

Exclusion criteria

Exclusion criteria: • The second/third vaccine dose less than 4 weeks prior to vaccination with the third/fourth dose. • Pregnant patients or women of childbearing potential (WOCBP) not on highly effective contraception (not acceptable methods: progesterone-only oral hormonal contraception, male/female condom without spermicide or cap, diaphragm or sponge with spermicide). • Solid organ transplant recipients transplanted less than 6 months before the third dose vaccination. • Serious side effect of previous SARS-CoV-2 vaccination. • Allergic to any vaccine excipients. • Acute febrile illness or acute infection. • Received any vaccination against other infectious diseases within the last four weeks prior to the third dose. • Have experienced breakthrough SARS-CoV-2 infection during or following primary vaccination. • Participation in other vaccine studies.

Design outcomes

Primary

Measure	Time frame
Main Objective: To investigate the immune response of a third SARS-CoV-2 mRNA vaccine dose in immunosuppressed patients with no or suboptimal vaccine response after the second dose. To investigate adverse events potentially linked to the third/fourth vaccine dose.;Secondary Objective: To investigate the immune response of a fourth SARS-CoV-2 mRNA vaccine dose in solid organ transplant recipients with no or suboptimal vaccine response after the third dose and to investigate the sustained immune response long-term.;Primary end point(s): Efficacy: SARS-CoV-2 SPIKE/RBD IgG antibody levels 4 weeks after administration of the third vaccine dose. Safety: Hospital admissions or deaths due to vaccine adverse events 6 weeks after the third/fourth dose. ;Timepoint(s) of evaluation of this end point: 4 weeks after administration of the third vaccine dose for the efficacy end point. 6 weeks after administration of the third vaccine dose for the safety end point.	—

Measure

Time frame

Main Objective: To investigate the immune response of a third SARS-CoV-2 mRNA vaccine dose in immunosuppressed patients with no or suboptimal vaccine response after the second dose. To investigate adverse events potentially linked to the third/fourth vaccine dose.;Secondary Objective: To investigate the immune response of a fourth SARS-CoV-2 mRNA vaccine dose in solid organ transplant recipients with no or suboptimal vaccine response after the third dose and to investigate the sustained immune response long-term.;Primary end point(s): Efficacy: SARS-CoV-2 SPIKE/RBD IgG antibody levels 4 weeks after administration of the third vaccine dose. Safety: Hospital admissions or deaths due to vaccine adverse events 6 weeks after the third/fourth dose. ;Timepoint(s) of evaluation of this end point: 4 weeks after administration of the third vaccine dose for the efficacy end point. 6 weeks after administration of the third vaccine dose for the safety end point.

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Secondary

Measure	Time frame
Secondary end point(s): SARS-CoV-2 SPIKE/RBD IgG antibody levels 4 weeks after administration of the fourth vaccine dose. Humoral immune response at 3- and 6-months and sustained response up to 1 year after the third/fourth dose. Cellular immune responses at 4 weeks, 3- and 6 months and sustained response up to 1 year after the third/fourth dose in a subset of patients. Length of sustained humoral immune response following three versus two doses or four versus two doses. ;Timepoint(s) of evaluation of this end point: Up to 1 years after the third/fourth vaccine doses.	—

Measure

Time frame

Secondary end point(s): SARS-CoV-2 SPIKE/RBD IgG antibody levels 4 weeks after administration of the fourth vaccine dose. Humoral immune response at 3- and 6-months and sustained response up to 1 year after the third/fourth dose. Cellular immune responses at 4 weeks, 3- and 6 months and sustained response up to 1 year after the third/fourth dose in a subset of patients. Length of sustained humoral immune response following three versus two doses or four versus two doses. ;Timepoint(s) of evaluation of this end point: Up to 1 years after the third/fourth vaccine doses.

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Countries

Norway

Contacts

Public ContactJohn Torgils Vaage

Oslo University Hospital

jtvaage@ous-hf.no4723070000

Outcome results

None listed

Source: EU CTR (via WHO ICTRP) · Data processed: Feb 4, 2026