TerminatedPhase 3

Study of Monovalent and Bivalent Recombinant Protein Vaccines Against COVID-19 in Adults 18 Years of Age and Older

Stopped: The study was terminated as per Sponsor decision

United States, Colombia, Ghana23,670 participantsStarted 2021-05-26

Plain-language summary

The purpose of this Phase III study is to assess the efficacy, safety, and immunogenicity of two CoV2 preS dTM-AS03 vaccines (monovalent and bivalent) as part of primary series vaccinations in a multi-stage approach, as well as a booster injection of a CoV2 preS dTM-AS03 vaccine, in adults 18 years of age and older. A total of approximately 21 046 participants are planned to be enrolled (5080 per study intervention group in Stage 1 and 5443 per study intervention group in Stage 2). Initial, double-blind, primary series study design is planned for 365 days post-last Initial injection (ie, approximately 386 days total) for each participant. Based on decisions of the Study Oversight Group, Stage 1 and Stage 2 participants will be invited to participate in an unblinded Crossover / Booster study design with duration as follows: * For participants who initially received vaccine: 12 months post-booster (ie, approximately 18 to 24 months) * For participants who initially received placebo: ≥ 4 months post-last dose of the primary series + 12 months post-booster (ie, approximately 28 to 34 months) * For participants who do not consent to continue in the unblinded Crossover / Booster part of the study, all study procedures will be stopped and participants will be discontinued from the study.

Who can participate

Age range

18 Years

Sex

ALL

See this in plain English?

AI-rewrites the medical criteria so a patient or caregiver can understand them. Always confirm with the trial site.

Inclusion Criteria: * Aged 18 years or older on the day of inclusion. * For persons living with human immunodeficiency virus (HIV), stable HIV infection determined by participant currently on antiretrovirals with CD4 count \> 200/mm3. * SARS-CoV-2 rapid serodiagnostic test performed at the time of enrollment to detect presence of SARS-CoV-2 antibodies. * Does not intend to receive an authorized/approved COVID-19 vaccine despite encouragement by the Investigator to receive the authorized vaccine available to them at the time of enrollment. * Informed consent form has been signed and dated * Able to attend all visits and to comply with all study procedures * Covered by health insurance, only if required by local, regional or national regulations * A female participant is eligible to participate if she is not pregnant or breastfeeding and one of the following conditions applies: * is of non-childbearing potential. To be considered of non-childbearing potential, a female must be post-menopausal for at least 1 year or surgically sterile, or * is of childbearing potential and agrees to use an effective contraceptive method or abstinence from at least 4 weeks prior to the first study intervention administration until at least 12 weeks after the second study intervention administration. A participant of childbearing potential must have a negative highly sensitive pregnancy test (urine or serum as required by local regulation) within 25 hours before any dose of study interventi…

Questions worth asking your doctor

Bring these to your next appointment. They're a starting point for a shared conversation — not a sign you qualify or a recommendation to enrol.

1Based on my diagnosis and history, is this trial worth exploring for me — or is there a standard treatment we should try first?
2What does this trial's phase tell us about how much is already known about its safety and benefit?
3What would taking part actually involve for me — visits, tests, time, and travel?
4What are the known and possible risks or side effects I should weigh, and how would they be monitored?
5If this trial isn't the right fit, what other options or trials would you suggest I look into?

Generated to help you prepare — always confirm anything about your own eligibility and care with the study team and your doctor.

Questions for the trial coordinator

The trial coordinator is the person who runs the study day to day. These cover the practical side — logistics, costs, and what taking part would actually mean for your life. The study team confirms whether you meet the criteria; these are questions to ask, not a sign you qualify.

1What does taking part actually involve week to week — how many visits, where, and how long does each one take?
2What costs are covered by the study, and what might I have to pay for myself, including travel, parking, or time off work?
3What happens during screening, and what happens if the study team confirms I don't meet the criteria after those tests?
4Who pays for the scans, blood work, and other tests the trial requires — the study, my insurance, or me?
5How will being in the trial affect my regular care, and will my own doctor stay informed and involved?
6Can I leave the trial at any point if I change my mind, and what would happen to my care if I do?

A starting point for the conversation — always confirm anything about your own eligibility, costs, and care with the study team and your doctor.

What they're measuring

Stage 1 and Stage 2: Number of Participants With Onset of Symptomatic Coronavirus Disease 2019 (COVID-19) Episode

Timeframe: From Day 36 up to Day 387

Stage 1 and Stage 2: Number of Participants With Solicited Injection Site and Systemic Reactions

Timeframe: Up to 7 days after each vaccination (post-dose on Days 1 and 22)

Stage 1 and Stage 2: Number of Participants With Unsolicited Non-Serious Adverse Events (AEs)

Timeframe: Up to 21 days after each vaccination (post-dose on Days 1 and 22)

Stage 1 and Stage 2: Number of Participants With Immediate Adverse Events

Timeframe: Up to 30 minutes after each vaccination (post-dose on Days 1 and 22)

Stage 1 and Stage 2: Number of Participants With Medically Attended Adverse Events (MAAE), Serious Adverse Events (SAE), and Adverse Events of Special Interest (AESI)

Timeframe: From first dose of study vaccine administration (Day 1) up to 387 days

Stage 1 and Stage 2: Percentage of Participants With Virologically-Confirmed SARS-CoV-2 Infection and/or Symptomatic COVID-19

Timeframe: From first dose of study vaccine administration (Day 1) up to 387 days

Trial details

NCT IDNCT04904549

SponsorSanofi Pasteur, a Sanofi Company

Sponsor typeINDUSTRY

Study typeINTERVENTIONAL

Primary completion2024-08-31

Results submitted2025-08-29

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