CompletedPhase 2

Immunogenicity of COVID-19 Vaccine on Heterologous Schedule

Taiwan100 participantsStarted 2021-09-15

Plain-language summary

This is a prospective, single blinded randomized homologous/heterologous prime-boost vaccine clinical study, designed to assess the immunogenicity of heterologous prime-boost immunization with AZD1222 and MVC-COV1901 in adults. Participants will be healthy adults at the age of 20-70 years who have had their first dose of COVID-19 vaccine, AZD1222. All eligible participants of 2 prime-boost interval strata (28 to 42, 56 to 70 days) will be 1:1 randomly assigned to receive a single dose of either: * Homologous group: Intramuscular injection the same vaccine as their prime dose AZD1222 * Heterologous group: Medigen COVID-19 vaccine MVC-COV1901. The treatment phase of this study will be conducted in a single-blind fashion such that the subject will not know the identity of the subjects' study treatment assignment. After receiving the treatment, the participants will remain on study for 168 days following the boost vaccination. For the study primary objective, immunogenicity will be assessed during the duration of the study, including serologic neutralizing antibody titer against SARS-CoV-2, serological quantification of binding antibody to SARS-CoV-2 antigen, SARS-CoV-2 antigen specific B cell and T cell frequencies and cytokine levels. And Safety will be assessed during the duration of the study as follows: * Solicited adverse events (AEs; local and systemic) will be assessed for 7 days following each vaccination (Day 0 through Day 7 for the boost vaccination). * Unsolicited AEs will be recorded for 28 days following the boost vaccination. * Serious adverse events (SAEs) will be recorded from signing of the informed consent form through Day 168. * Adverse events of special interest (AESIs) will be recorded from the boost vaccination through Day 168. This study is going to be conducted in a single medical center in Taiwan. An appropriate number of participants will be screened to achieve approximately 44 evaluable participants for each group. Participants in each group will be divided into two subgroups according to the intervals, 28-42 days and 56-70 days, between the prime and booster doses.

Who can participate

Age range

20 Years – 70 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

. Participant is willing and able to give written informed consent for participation in the trial.
. Male or Female, aged from 20 to 70 years
. Has received one dose of the AZD1222 within 28-70 days before randomization. Evidence of this will be gathered from medical history and/or medical records including the COVID-19 vaccine registration yellow card.
. Female participant must:
. Be either of non-childbearing potential, i.e. surgically sterilized (defined as having undergone hysterectomy and/or bilateral oophorectomy and/or bilateral salpingectomy; tubal ligation alone is not considered sufficient) or one year post-menopausal;
. Or, if of childbearing potential, be abstinent or agree to use medically effective contraception on enrolment continuously until 90 days after boost immunization of study intervention.

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.

1This trial tested mixing different COVID-19 vaccines in a heterologous schedule — could that approach be relevant to my own vaccination history, and is there anything in the results my doctor thinks is worth knowing?
2Since this was a Phase 2 trial focused on immunogenicity, meaning it measured antibody responses rather than long-term protection or safety in large populations, what does my doctor think we still don't know from a study at this stage?
3The trial measured neutralizing antibodies against SARS-CoV-2 as its main outcome — how does my doctor interpret what a strong or weak neutralizing antibody response actually means for real-world protection?
4Now that this trial is completed, has my doctor seen or read any published results, and do the findings change their recommendations about how I should approach COVID-19 vaccination?
5Given that this study enrolled healthy participants, would my doctor consider its findings applicable to my specific health situation, or are there reasons my immune response might differ from what was studied?

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

Immunogenicity: Neutralizing antibody against SARS-CoV-2

Timeframe: Day 28 after booster dose

Trial details

NCT IDNCT05054621

SponsorChang Gung Memorial Hospital

Sponsor typeOTHER

Study typeINTERVENTIONAL

Primary completion2022-08-31

View on ClinicalTrials.gov More Covid-19 trials

Plain-language summary

Who can participate

Age range

20 Years – 70 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

. Participant is willing and able to give written informed consent for participation in the trial.
. Male or Female, aged from 20 to 70 years
. Has received one dose of the AZD1222 within 28-70 days before randomization. Evidence of this will be gathered from medical history and/or medical records including the COVID-19 vaccine registration yellow card.
. Female participant must:
. Be either of non-childbearing potential, i.e. surgically sterilized (defined as having undergone hysterectomy and/or bilateral oophorectomy and/or bilateral salpingectomy; tubal ligation alone is not considered sufficient) or one year post-menopausal;
. Or, if of childbearing potential, be abstinent or agree to use medically effective contraception on enrolment continuously until 90 days after boost immunization of study intervention.

Immunogenicity of COVID-19 Vaccine on Heterologous Schedule

Plain-language summary

Who can participate

Inclusion criteria

Questions worth asking your doctor

Questions for the trial coordinator

What they're measuring

Trial details

Immunogenicity of COVID-19 Vaccine on Heterologous Schedule

Plain-language summary

Who can participate

Inclusion criteria

Questions worth asking your doctor

Questions for the trial coordinator

What they're measuring

Trial details

Exclusion criteria