COVID-19 VaccinationPhase 4NCT05057169
Randomized Trial of COVID-19 Booster Vaccinations (Cobovax Study)
A Phase 4 study testing BNT162b2 and CoronaVac in people with COVID-19 Vaccination, run by The University of Hong Kong at 1 site in Hong Kong.
Trial summary
Randomized comparison of 3rd dose with inactivated vaccine (CoronaVac) or mRNA vaccine (Comirnaty) in adults who previously received two doses of CoronaVac (Sinovac) or two doses of BNT162b2 (Comirnaty, BioNTech/Fosun Pharma) at least 6 months earlier. Read more about this study
- Who is it for?
- Ages 18 years and olderHealthy volunteers can take part
- Conditions the study is for
- COVID-19 Vaccination
- What is being tested?
- BNT162b2 and CoronaVac
- Type of treatment
- Vaccines, Injection or infusion
- Could I receive a placebo?
- No, everyone receives an active treatment
- How many people
- 451 participants
- Where
- 1 siteHong Kong
- Study dates
- 18 Nov 2021to 31 Dec 2025
- Phase
- Phase 4
- Are there results?
- None posted in the registry
Key requirements
Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.
- Ages 18 years and older
- All sexes
- Healthy volunteers accepted
- Adult, Older adult
Who may be able to join
- Aged 18 years or older at enrolment.
- Have received two doses of BNT162b2 OR two doses of CoronaVac, with the most recent dose at least six months prior to enrolment.
- Currently resident and planning to remain resident in Hong Kong during the duration of the study, i.e. for 12 months after enrolment.
- Agreement to refrain from blood donation during the course of the study.
- Willing to provide blood samples for all the required time points.
- The individual or their caregiver have a home phone or cellular or mobile phone for communications purpose.
- Capable of providing informed consent.
Who cannot join
- A history of laboratory-confirmed or clinically confirmed COVID-19 infection prior to enrolment.
- Have previously already received one or two doses of any COVID-19 vaccines except CoronaVac or BNT162b2, for example but not limited to BBIBP-CorV (inactivated vaccine, Sinopharm), AZD1222 (adenovirus vector-based vaccine, Oxford/AstraZeneca), Sputnik V (adenovirus vector-based vaccine, Gamaleya Research Institute) and Ad26.COV2.S (adenovirus vector-based vaccine, Johnson \& Johnson).
- Individuals who report any medical condition, or as determined by a clinician, not suitable to receive mRNA or inactivated COVID-19 vaccines, including but not limited to allergies to the active substance or other ingredients of the vaccine.
- Currently with diagnosed medical conditions related to their immune system.
- Use of medication that impairs immune system in the last 6 months, except topical steroids or short-term oral steroids (course lasting ≤ 14 days).
- Administration of immunoglobulins and/or any blood products within 90 days preceding the planned administration of the study vaccines.
- Pregnancy, lactation or intention to become pregnant in the coming 3 months.
Trial locations and contacts
1 site in 1 country.
About this study
Randomized comparison of 3rd dose with inactivated vaccine (CoronaVac) or mRNA vaccine (Comirnaty) in adults who previously received two doses of CoronaVac (Sinovac) or two doses of BNT162b2 (Comirnaty, BioNTech/Fosun Pharma) at least 6 months earlier.
Read the detailed description
Background: The accrual of population immunity to COVID-19 could allow life to return to pre- pandemic normality. Immunity can be acquired through natural infections or, preferably, by vaccination. An unprecedented global effort has succeeded in developing a number of COVID-19 vaccines. All vaccines against COVID-19 approved until now have originally been developed as either a single dose or following a homologous two-dose regimen. Inactivated COVID-19 vaccines have shown inferior immunogenicity compared to mRNA vaccines but there are no studies comparing the advantages of alternative booster doses in individuals who have previously received two doses of an inactivated COVID-19 vaccine or two doses of an mRNA vaccine.
Aims and primary objectives: The aims of this study are: (1) to compare the SARS-CoV-2 antibody responses to one dose of BNT162b2 (mRNA vaccine, Fosun/BioNTech) versus one dose of CoronaVac (inactivated vaccine, Sinovac) in individuals who have previously received two doses of COVID-19 vaccination using BNT162b2 (mRNA vaccine, Fosun/BioNTech) or CoronaVac (inactivated vaccine, Sinovac), and (2) to assess the reactogenicity and safety of one booster dose of BNT162b2 and CoronaVac. The specific primary objective of our study is to assess the vaccine (humoral) immunogenicity, proxied by SARS-CoV-2 serum neutralizing antibody titers, of one booster dose of BNT162b2 or CoronaVac at 28 days after the booster dose in individuals who have previously received two doses of a COVID-19 vaccine.
Study design: Randomized open label trial in adults aged 18 years of age or older (at enrolment). The duration of participation for each participant will be 12 months from the administration of the vaccination booster dose. The immune response and reactogenicity of one dose of BNT162b2 or CoronaVac will be investigated in individuals who previously received two doses of COVID-19 vaccine at least 6 months earlier. Participants will be enrolled shortly before receiving the booster dose of BNT162b2 (day 0), with blood collection at days 0, 28, 182 and 365 days after enrolment for analysis of humoral immune responses. A subset of 25% of participants will provide additional blood samples at day 0, 7 and 30 for assessment of cellular immune responses.
Main outcomes: The primary outcome is the vaccine (humoral) immunogenicity measured as SARS- CoV-2 serum neutralizing antibodies, evaluated as the geometric mean titer (GMT) at 28 days after the booster doses. The secondary outcomes include (1) a comparison of SARS-CoV-2 serum neutralizing antibodies as the geometric mean fold rise from baseline to each post-vaccination timepoint (i.e. at days 28, 182 and 365); (2) a comparison of cellular immune responses at day 7 and 30 compared to day 0; (3) descriptive analysis of the reactogenicity and safety profiles of the booster doses.
Target population: Adults aged 18 years or older
Number of subjects planned: 400 participants to be recruited in 2021-22
Study Duration: 12 months, from September 2021 through to March 2023
Potential implications: This study will provide important evidence into the comparative effects of using a dose of mRNA vaccine or inactivated vaccine to boost the immune response in individuals that had previously received two doses of COVID-19 vaccination. This information together with data collected on reactogenicity and safety could inform COVID-19 vaccination policy locally and internationally.
- Conditions
- COVID-19 Vaccination
- Being tested
- BNT162b2, CoronaVac
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
BNT162b2Biological
Also called Comirnaty
BNT162b2 is a nucleoside-modified mRNA encoding the trimerized SARS-CoV-2 spike glycoprotein. The vaccine is formulated in lipid nanoparticles that increase the efficiency of delivery of the mRNA into cells after intramuscular injection. BNT162b2 encodes the SARS- CoV-2 full-length spike, modified by two proline mutations to lock it in the prefusion conformation and more closely recreate the intact virus with which the elicited virus- neutralizing antibodies interact. mRNA vaccines use the pathogen's genetic code as the vaccine; hence they exploit the host cells to translate the code and generate the target spike protein. The protein then acts as an intracellular antigen to stimulate the immune response of the vaccinated individual. The mRNA is then degraded within days.
CoronaVacBiological
CoronaVac is a Vero cell-based, aluminium hydroxide-adjuvanted, β-propiolactone- inactivated vaccine based on the CZ02 strain. This strain of SARS-CoV-2 was isolated from the bronchoalveolar lavage of a hospitalized patient and is closely related to the 2019-nCoV- BetaCoV Wuhan/WIV04/2019 strain. Each 0.5 ml dose is composed of 3 μg of inactivated SARS-CoV-2 virus. The excipients are aluminium hydroxide, disodium hydrogen phosphate, sodium dihydrogen phosphate, sodium chloride, and water for injection.
| Study group | Role | What they receive |
|---|---|---|
| BNT162b2 third dose after two doses of BNT162b2 | Experimental | Not described Receives: Biological: BNT162b2 |
| CoronaVac third dose after two doses of BNT162b2 | Experimental | Not described Receives: Biological: CoronaVac |
| BNT162b2 third dose after two doses of CoronaVac | Experimental | Not described Receives: Biological: BNT162b2 |
| CoronaVac third dose after two doses of CoronaVac | Experimental | Not described Receives: Biological: CoronaVac |
What is being measured
The primary outcome is the main question the study is designed to answer.
Geometric mean titer (GMT) of SARS-CoV-2 serum neutralizing antibodies
The primary outcome measure is the vaccine (humoral) immunogenicity at 28 days after the booster dose, measured as geometric mean titer (GMT) of SARS-CoV-2 serum neutralizing antibodies using plaque reduction neutralization test (PRNT).
Measured: 28 days after vaccination
Secondary outcomes (5)
Geometric mean titer (GMT) of SARS-CoV-2 serum neutralizing antibodies
The GMT of SARS-CoV-2 serum PRNT titers after the booster dose at Days 182 and 365.
Measured: 182 and 365 days after vaccination
Geometric mean fold rise of SARS-CoV-2 serum neutralizing antibodies
The geometric mean fold rise (GMFR) of SARS-CoV-2 serum neutralizing antibody titers from baseline to each post-vaccination timepoint measured.
Measured: Day 28, 49, 182 and 365 after vaccination
T-cell responses to vaccination
Vaccine-specific IFN-γ+CD4+ and IFN-γ+CD8+ T-cell response at Day 7 and 28.
Measured: 7 and 28 days after vaccination
Reactogenicity
Incidence of solicited local and systemic adverse events after the booster dose of vaccination.
Measured: 7 days after vaccination or until symptoms resolve
Hospitalizations from any cause
Incidence of hospitalizations during the year after receipt of the booster dose.
Measured: One year after vaccination
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted27 Sep 2021
- Study start18 Nov 2021
- Primary completion31 Dec 2024
- Study completion31 Dec 2025
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Publications (2)Papers the sponsor has linked to this study.
- Other trials for COVID-19 VaccinationStudies of the same condition, open and under way.
- More trials run by The University of Hong KongThe sponsor's other registered studies.
- What the trial phases meanHow a treatment moves from first tests in people to approval.
More details
For doctors and researchers: how the study is designed, who runs it, and its registry IDs.
Study design
- Study type
- Interventional
- Phase
- Phase 4
- Primary purpose
- Prevention
- Allocation
- Randomised
- Intervention model
- Parallel groups
- Masking
- Triple blind
- Who is masked
- Participant, Investigator, Outcomes assessor
- Enrolment
- 451 participants (actual)
Sponsor and investigators
- Lead sponsor
- The University of Hong Kong
- Sponsor type
- University, hospital or other
- Responsible party
- Sponsor
- Investigators
- Benjamin J Cowling, PhD, Principal investigator, The University of Hong Kong
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT05057169
- Sponsor's protocol ID
- BJC053
- Status last verified
- Apr 2026
- First submitted
- 24 Sep 2021
- Last updated
- 15 May 2026
- Results posted
- No
- Data monitoring committee
- Yes
- FDA-regulated drug
- No
- FDA-regulated device
- No
- Individual data sharing
- Yes
Publications
Cohen CA, Leung NHL, Kaewpreedee P, Lee KWK, Jia JZ, Cheung AWL, Cheng SMS, Mori M, Ip DKM, Poon LLM, Peiris JSM, Cowling BJ, Valkenburg SA. Antibody Fc receptor binding and T cell responses to homologous and heterologous immunization with inactivated or mRNA vaccines against SARS-CoV-2. Nat Commun. 2024 Aug 27;15(1):7358. doi: 10.1038/s41467-024-51427-1.
PubMed 39191745Leung NHL, Cheng SMS, Cohen CA, Martin-Sanchez M, Au NYM, Luk LLH, Tsang LCH, Kwan KKH, Chaothai S, Fung LWC, Cheung AWL, Chan KCK, Li JKC, Ng YY, Kaewpreedee P, Jia JZ, Ip DKM, Poon LLM, Leung GM, Peiris JSM, Valkenburg SA, Cowling BJ. Comparative antibody and cell-mediated immune responses, reactogenicity, and efficacy of homologous and heterologous boosting with CoronaVac and BNT162b2 (Cobovax): an open-label, randomised trial. Lancet Microbe. 2023 Sep;4(9):e670-e682. doi: 10.1016/S2666-5247(23)00216-1. Epub 2023 Aug 4.
PubMed 37549680
Study at a glance
From the registry record, last updated by the sponsor on 15 May 2026. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- Randomized Trial of COVID-19 Booster Vaccinations (Cobovax Study)
- ClinicalTrials.gov ID
- NCT05057169
- Acronym / sponsor ID
- BJC053
- Conditions
- COVID-19 Vaccination
- Phase
- Phase 4
- Study type
- Interventional
- Recruitment status
- Completed
- Enrolment
- 451 participants (actual)
- Lead sponsor
- The University of Hong KongUniversity, hospital or other
- Study start
- 18 Nov 2021 (actual)
- Primary completion
- 31 Dec 2024 (actual)
- Study completion
- 31 Dec 2025 (actual)
- First posted
- 27 Sep 2021 (actual)
- Results
- Not posted in the source record
Clinical summary
The research question as the sponsor registered it. This describes what the study plans to test, not what it found.
Randomized comparison of 3rd dose with inactivated vaccine (CoronaVac) or mRNA vaccine (Comirnaty) in adults who previously received two doses of CoronaVac (Sinovac) or two doses of BNT162b2 (Comirnaty, BioNTech/Fosun Pharma) at least 6 months earlier.
Detailed description
Background: The accrual of population immunity to COVID-19 could allow life to return to pre- pandemic normality. Immunity can be acquired through natural infections or, preferably, by vaccination. An unprecedented global effort has succeeded in developing a number of COVID-19 vaccines. All vaccines against COVID-19 approved until now have originally been developed as either a single dose or following a homologous two-dose regimen. Inactivated COVID-19 vaccines have shown inferior immunogenicity compared to mRNA vaccines but there are no studies comparing the advantages of alternative booster doses in individuals who have previously received two doses of an inactivated COVID-19 vaccine or two doses of an mRNA vaccine.
Aims and primary objectives: The aims of this study are: (1) to compare the SARS-CoV-2 antibody responses to one dose of BNT162b2 (mRNA vaccine, Fosun/BioNTech) versus one dose of CoronaVac (inactivated vaccine, Sinovac) in individuals who have previously received two doses of COVID-19 vaccination using BNT162b2 (mRNA vaccine, Fosun/BioNTech) or CoronaVac (inactivated vaccine, Sinovac), and (2) to assess the reactogenicity and safety of one booster dose of BNT162b2 and CoronaVac. The specific primary objective of our study is to assess the vaccine (humoral) immunogenicity, proxied by SARS-CoV-2 serum neutralizing antibody titers, of one booster dose of BNT162b2 or CoronaVac at 28 days after the booster dose in individuals who have previously received two doses of a COVID-19 vaccine.
Study design: Randomized open label trial in adults aged 18 years of age or older (at enrolment). The duration of participation for each participant will be 12 months from the administration of the vaccination booster dose. The immune response and reactogenicity of one dose of BNT162b2 or CoronaVac will be investigated in individuals who previously received two doses of COVID-19 vaccine at least 6 months earlier. Participants will be enrolled shortly before receiving the booster dose of BNT162b2 (day 0), with blood collection at days 0, 28, 182 and 365 days after enrolment for analysis of humoral immune responses. A subset of 25% of participants will provide additional blood samples at day 0, 7 and 30 for assessment of cellular immune responses.
Main outcomes: The primary outcome is the vaccine (humoral) immunogenicity measured as SARS- CoV-2 serum neutralizing antibodies, evaluated as the geometric mean titer (GMT) at 28 days after the booster doses. The secondary outcomes include (1) a comparison of SARS-CoV-2 serum neutralizing antibodies as the geometric mean fold rise from baseline to each post-vaccination timepoint (i.e. at days 28, 182 and 365); (2) a comparison of cellular immune responses at day 7 and 30 compared to day 0; (3) descriptive analysis of the reactogenicity and safety profiles of the booster doses.
Target population: Adults aged 18 years or older
Number of subjects planned: 400 participants to be recruited in 2021-22
Study Duration: 12 months, from September 2021 through to March 2023
Potential implications: This study will provide important evidence into the comparative effects of using a dose of mRNA vaccine or inactivated vaccine to boost the immune response in individuals that had previously received two doses of COVID-19 vaccination. This information together with data collected on reactogenicity and safety could inform COVID-19 vaccination policy locally and internationally.
Study design
- Primary purpose
- Prevention
- Allocation
- Randomised
- Intervention model
- Parallel groups
- Masking
- Triple blind (participant, investigator, outcomes assessor)
- Number of arms
- 4
| Arm | Type | Receives |
|---|---|---|
| BNT162b2 third dose after two doses of BNT162b2 | Experimental | Biological: BNT162b2 |
| CoronaVac third dose after two doses of BNT162b2 | Experimental | Biological: CoronaVac |
| BNT162b2 third dose after two doses of CoronaVac | Experimental | Biological: BNT162b2 |
| CoronaVac third dose after two doses of CoronaVac | Experimental | Biological: CoronaVac |
Who may qualify
- Ages
- 18 years and older
- Sex
- All
- Healthy volunteers
- Accepted
- Age groups
- Adult, Older adult
Key inclusion criteria (7 listed)
- Aged 18 years or older at enrolment.
- Have received two doses of BNT162b2 OR two doses of CoronaVac, with the most recent dose at least six months prior to enrolment.
- Currently resident and planning to remain resident in Hong Kong during the duration of the study, i.e. for 12 months after enrolment.
- Agreement to refrain from blood donation during the course of the study.
- Willing to provide blood samples for all the required time points.
Key exclusion criteria (7 listed)
- A history of laboratory-confirmed or clinically confirmed COVID-19 infection prior to enrolment.
- Have previously already received one or two doses of any COVID-19 vaccines except CoronaVac or BNT162b2, for example but not limited to BBIBP-CorV (inactivated vaccine, Sinopharm), AZD1222 (adenovirus vector-based vaccine, Oxford/AstraZeneca), Sputnik V (adenovirus vector-based vaccine, Gamaleya Research Institute) and Ad26.COV2.S (adenovirus vector-based vaccine, Johnson \& Johnson).
- Individuals who report any medical condition, or as determined by a clinician, not suitable to receive mRNA or inactivated COVID-19 vaccines, including but not limited to allergies to the active substance or other ingredients of the vaccine.
- Currently with diagnosed medical conditions related to their immune system.
- Use of medication that impairs immune system in the last 6 months, except topical steroids or short-term oral steroids (course lasting ≤ 14 days).
Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.
Interventions
| Intervention | Type | Arms |
|---|---|---|
| BNT162b2Also: ComirnatyBNT162b2 is a nucleoside-modified mRNA encoding the trimerized SARS-CoV-2 spike glycoprotein. The vaccine is formulated in lipid nanoparticles that increase the efficiency of delivery of the mRNA into cells after intramuscular injection. BNT162b2 encodes the SARS- CoV-2 full-length spike, modified by two proline mutations to lock it in the prefusion conformation and more closely recreate the intact virus with which the elicited virus- neutralizing antibodies interact. mRNA vaccines use the pathogen's genetic code as the vaccine; hence they exploit the host cells to translate the code and generate the target spike protein. The protein then acts as an intracellular antigen to stimulate the immune response of the vaccinated individual. The mRNA is then degraded within days. | Biological | BNT162b2 third dose after two doses of BNT162b2, BNT162b2 third dose after two doses of CoronaVac |
| CoronaVacCoronaVac is a Vero cell-based, aluminium hydroxide-adjuvanted, β-propiolactone- inactivated vaccine based on the CZ02 strain. This strain of SARS-CoV-2 was isolated from the bronchoalveolar lavage of a hospitalized patient and is closely related to the 2019-nCoV- BetaCoV Wuhan/WIV04/2019 strain. Each 0.5 ml dose is composed of 3 μg of inactivated SARS-CoV-2 virus. The excipients are aluminium hydroxide, disodium hydrogen phosphate, sodium dihydrogen phosphate, sodium chloride, and water for injection. | Biological | CoronaVac third dose after two doses of BNT162b2, CoronaVac third dose after two doses of CoronaVac |
Primary outcome
Geometric mean titer (GMT) of SARS-CoV-2 serum neutralizing antibodies
Time frame: 28 days after vaccination
The primary outcome measure is the vaccine (humoral) immunogenicity at 28 days after the booster dose, measured as geometric mean titer (GMT) of SARS-CoV-2 serum neutralizing antibodies using plaque reduction neutralization test (PRNT).
5 secondary outcomes
Geometric mean titer (GMT) of SARS-CoV-2 serum neutralizing antibodies
Time frame: 182 and 365 days after vaccination
Geometric mean fold rise of SARS-CoV-2 serum neutralizing antibodies
Time frame: Day 28, 49, 182 and 365 after vaccination
T-cell responses to vaccination
Time frame: 7 and 28 days after vaccination
Reactogenicity
Time frame: 7 days after vaccination or until symptoms resolve
Hospitalizations from any cause
Time frame: One year after vaccination
Results and safety
The study is completed, but results are not available in the source record. That does not mean the treatment did or did not work.
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 15 May 2026.
- Derived from this study: PubMed 39191745Cohen CA, Leung NHL, Kaewpreedee P, Lee KWK, Jia JZ, Cheung AWL, Cheng SMS, Mori M, Ip DKM, Poon LLM, Peiris JSM, Cowling BJ, Valkenburg SA. Antibody Fc receptor binding and T cell responses to homologous and heterologous immunization with inactivated or mRNA vaccines against SARS-CoV-2. Nat Commun. 2024 Aug 27;15(1):7358. doi: 10.1038/s41467-024-51427-1.
- Derived from this study: PubMed 37549680Leung NHL, Cheng SMS, Cohen CA, Martin-Sanchez M, Au NYM, Luk LLH, Tsang LCH, Kwan KKH, Chaothai S, Fung LWC, Cheung AWL, Chan KCK, Li JKC, Ng YY, Kaewpreedee P, Jia JZ, Ip DKM, Poon LLM, Leung GM, Peiris JSM, Valkenburg SA, Cowling BJ. Comparative antibody and cell-mediated immune responses, reactogenicity, and efficacy of homologous and heterologous boosting with CoronaVac and BNT162b2 (Cobovax): an open-label, randomised trial. Lancet Microbe. 2023 Sep;4(9):e670-e682. doi: 10.1016/S2666-5247(23)00216-1. Epub 2023 Aug 4.
- Individual participant dataSharing planned: Yes
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Referral and contact
AzTrials does not enrol participants or take referrals. Contact the study team or a site listed below; they decide who can take part. This study is not recruiting at the moment.
Benjamin J Cowling, PhD principal investigator
The University of Hong Kong
1 site in 1 country: see every site and its status.
Questions about this trial
What is this clinical trial studying?
A Phase 4 study testing BNT162b2 and CoronaVac in people with COVID-19 Vaccination, run by The University of Hong Kong at 1 site in Hong Kong.
The full registered description is in the About this study section and the official record.
Who may be eligible to take part?
The sponsor lists 7 inclusion and 7 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.
Is this clinical trial currently recruiting?
The record says: finished, as of the sponsor's last update on 15 May 2026. Status can change between updates, so confirm with the study contact before making plans.
Where is the study taking place?
The record lists 1 site in Hong Kong. Whether a site is taking part right now should be confirmed with that site. See every site.
What are the possible benefits and risks?
They depend on the study and the treatment, and no study can promise a benefit. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.
What does this phase mean?
Phase 4 studies take place after a treatment is approved, to learn more about its long-term benefits and risks in everyday use.
Not every study follows the same path, and some studies (observational studies, device studies) have no phase.
Are results available for this study?
The study is completed, but results are not available in the source record. That does not mean the treatment did or did not work.
How can a doctor refer a patient or contact the research team?
The record lists no contact. The official record names the sponsor, who can be asked directly. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
Geometric mean titer (GMT) of SARS-CoV-2 serum neutralizing antibodies (time frame: 28 days after vaccination). It is what the study was designed to measure, not a finding.
Where can I read the original study information?
On the ClinicalTrials.gov record for NCT05057169, which also lists 2 linked publications.
Does a listing mean the treatment is approved or proven to work?
No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.
How often is this information updated?
AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 15 May 2026; AzTrials last refreshed its copy on 7 Nov 2026.