HPV InfectionPhase 4Add-VaccNCT04953130
Adding Male Single Dose HPV Vaccination to Female HPV Vaccination in Tanzania
A Phase 4 study testing Gardasil® HPV vaccine in people with HPV Infection and Vaccine Preventable Disease, run by London School of Hygiene and Tropical Medicine at 1 site in Tanzania.
Trial summary
Add-Vacc is an unblinded cluster-randomised trial (CRT) with two arms: (i) the national HPV vaccination programme (girls aged ~14 years, control arm) and (ii) the national programme plus single-dose male HPV vaccination given to a multi-year cohort of boys (intervention arm). Read more about this study
- Who is it for?
- Ages 14 to 18 years, men onlyHealthy volunteers can take part
- Conditions the study is for
- HPV Infection, Vaccine Preventable Disease
- What is being tested?
- Gardasil® HPV vaccine
- Type of treatment
- Vaccines
- Could I receive a placebo?
- No, everyone receives an active treatment
- How many people
- 10,400 participants
- Where
- 1 siteTanzania
- Study dates
- 1 Aug 2022to Dec 2026
- Phase
- Phase 4
- Are there results?
- Not yet: the study is under way
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 14 to 18 years
- Men only
- Healthy volunteers accepted
- Child, Adult
Who may be able to join
- Parents and adult male participants (aged 18 years) must sign an ICF and male participants aged less than 18 years must sign an informed assent form (IAF), indicating that they understand the purpose of and procedures required for the study and are willing to participate in the study and to receive HPV vaccination. If the parent or participant cannot read or write, the procedures must be explained and informed consent/assent must be witnessed by a literate third party who is not involved in the conduct of the study.
- Participants must have been born male, and must be aged 14 to 18 years inclusive at time of vaccination.
- Participants must be living in an intervention community (cluster).
- Participants must be willing and able to comply with the protocol requirements.
- Participants must agree to avoid all non-trial immunisations in the 14 days following vaccination with the trial vaccine, other than emergency vaccinations such as post-exposure rabies or tetanus vaccinations.
- Participants must be healthy as determined by a medical history. A physical examination will be conducted if necessary according to the clinician's judgement.
Who cannot join
- Boys will be excluded from HPV vaccination if:
- They have previously been vaccinated against HPV.
- They have a history of allergy or anaphylaxis to one or more of the HPV vaccine components, to yeast or to latex.
- They are enrolled in another vaccine research study that specifically specifies that they must not participate in a study of another vaccine
- They have been diagnosed with a chronic condition (except HIV, as per the comment above), such as an autoimmune condition, sickle cell disease, degenerative disease, neurologic or genetic disease, among others;
- There are significant conditions or clinically significant findings for which, in the opinion of the investigator, participation would not be in the best interest of the participant (e.g., it would compromise their safety or well-being).
Trial locations and contacts
1 site in 1 country. Contact the study team or a site near you to ask about taking part.
Deborah Watson-Jones, MD, PhD contact
Tanzania1 site, 1 recruiting
- Recruiting
Mwanza Intervention Trials Unit
Mwanza
John Changalucha, MSc, jchangalucha@yahoo.com
About this study
Add-Vacc is an unblinded cluster-randomised trial (CRT) with two arms: (i) the national HPV vaccination programme (girls aged ~14 years, control arm) and (ii) the national programme plus single-dose male HPV vaccination given to a multi-year cohort of boys (intervention arm). The CRT will be conducted in 26 communities/clusters (13 per arm) in northern Tanzania. Boys aged 14 to 18 years in the intervention arm will receive one dose of the 4-valent HPV vaccine (Gardasil®) that protects against HPV 6, 11, 16, and 18. Population genital HPV prevalence in 18 to 21-year-olds will be compared between intervention clusters (female and male vaccination) and control clusters (female vaccination only) at 3 years after the intervention. Blood sampling for immune responses and adverse event data collection will be performed in a subset of 200 male subjects in selected intervention clusters.
- Conditions
- HPV Infection, Vaccine Preventable Disease
- Being tested
- Gardasil® HPV vaccine
- Medical subject headings
- Papillomavirus Infections, Vaccine-Preventable Diseases
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
Gardasil® HPV vaccineBiological
Also called 4-valent HPV vaccine
Single dose 4-valent HPV vaccine in males. Gardasil®, manufactured by MSD, consists of a licensed prophylactic virus-like particle (VLP) vaccine that protects against 4 HPV genotypes (HPV 6, 11, 16, 18).
| Study group | Role | What they receive |
|---|---|---|
| Male vaccination + national HPV vaccination programme | Experimental | Single dose of the 4-valent HPV vaccine (Gardasil®; Merck \& Co.) offered to all eligible boys aged 14 to 18 years in the 13 intervention communities. Girls aged 14 years are offered 2 doses of Gardasil® through the Tanzanian national HPV vaccine programme Receives: Biological: Gardasil® HPV vaccine |
| National HPV vaccination programme only | Active comparator | Girls aged 14 years are offered 2 doses of Gardasil® through the Tanzanian national HPV vaccine programme Receives: Biological: Gardasil® HPV vaccine |
What is being measured
The primary outcome is the main question the study is designed to answer.
Impact of adding single-dose male HPV vaccination to the national HPV vaccination programme in girls on population 4-valent HPV genotype prevalence in 18 to 21-year-old females and males
Prevalence of 4-valent vaccine HPV genotype DNA (HPV 6, 11, 16 or 18) in males and females aged 18 to 21 years in intervention clusters and control clusters 36 months post-male vaccination
Measured: Month 36
Secondary outcomes (5)
Immunogenicity and safety of single dose 4-valent HPV vaccination in boys
Proportion seroconverting to, and geometric mean antibody titres (GMTs) for, HPV vaccine genotypes, and safety and tolerability (local and systemic adverse events), measured in a subset of 200 vaccinated boys
Measured: Month 12, 24 and 36
Impact of female-only vaccination through the national vaccination programme on population HPV prevalence in 18 to 21-year-old males and females
The proportion of females, and of males, aged 18 to 21 years in the control arm with detectable genital 4-valent HPV vaccine genotype DNA at baseline and at M36.
Measured: Month 36
Uptake of dose 1 and coverage of dose 2 in eligible target groups for the national HPV vaccination programme;
The proportion of females aged 16 years who received 1 dose of HPV vaccine (uptake) and who complete 2 doses (coverage) by arm at baseline and M36
Measured: Month 36
Acceptability of a gender-neutral approach to HPV vaccination
Self-reported acceptability of and barriers to receiving male vaccination by community members and to delivering male HPV vaccination by health care workers (HCW)
Measured: Month 24
Cost-effectiveness of adding a multi-year single dose male HPV vaccination strategy to the national female HPV vaccination programme
Incremental cost-effectiveness ratio for single dose male vaccination plus existing female vaccination programme compared to female vaccination only
Measured: Month 36
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted7 Jul 2021
- Study start1 Aug 2022
- Primary completionDec 2026 (estimated)
- Study completionDec 2026 (estimated)
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Publications (1)Papers the sponsor has linked to this study.
- Other trials for HPV InfectionStudies of the same condition, open and under way.
- 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
- Model description
- Cluster randomised trial with 26 communities (13 per arm)
- Masking
- Single blind
- Who is masked
- Outcomes assessor
- Enrolment
- 10,400 participants (estimated)
Sponsor and investigators
- Lead sponsor
- London School of Hygiene and Tropical Medicine
- Sponsor type
- University, hospital or other
- Collaborators
- Mwanza Intervention Trials Unit, National Institute for Medical Research, York Biomedical Research Institute, Hull York Medical School, University of York, Cancer Epidemiology Research Programme Institut Català d' Oncologia, Karolinska Institute Department of Laboratory Medicine, University of Cambridge
- Responsible party
- Sponsor
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT04953130
- Sponsor's protocol ID
- MITU-003
- Acronym
- Add-Vacc
- Status last verified
- Aug 2026
- First submitted
- 28 Jun 2021
- Last updated
- 8 Sep 2026
- Results posted
- No
- Data monitoring committee
- Yes
- FDA-regulated drug
- Yes
- FDA-regulated device
- No
- Individual data sharing
- Undecided
Publications
Bergman H, Henschke N, Arevalo-Rodriguez I, Buckley BS, Crosbie EJ, Davies JC, Dwan K, Golder SP, Loke YK, Probyn K, Petkovic J, Villanueva G, Morrison J. Human papillomavirus (HPV) vaccination for the prevention of cervical cancer and other HPV-related diseases: a network meta-analysis. Cochrane Database Syst Rev. 2025 Nov 24;11(11):CD015364. doi: 10.1002/14651858.CD015364.pub2.
PubMed 41276263
Study at a glance
From the registry record, last updated by the sponsor on 8 Sep 2026. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- Adding Male Single Dose HPV Vaccination to Female HPV Vaccination in Tanzania
- ClinicalTrials.gov ID
- NCT04953130
- Acronym / sponsor ID
- Add-Vacc / MITU-003
- Conditions
- HPV Infection, Vaccine Preventable Disease
- Phase
- Phase 4
- Study type
- Interventional
- Recruitment status
- Recruiting
- Enrolment
- 10,400 participants (estimated)
- Lead sponsor
- London School of Hygiene and Tropical MedicineUniversity, hospital or other
- Collaborators
- Mwanza Intervention Trials Unit, National Institute for Medical Research, York Biomedical Research Institute, Hull York Medical School, University of York, Cancer Epidemiology Research Programme Institut Català d' Oncologia, Karolinska Institute Department of Laboratory Medicine, University of Cambridge
- Study start
- 1 Aug 2022 (actual)
- Primary completion
- Dec 2026 (estimated)
- Study completion
- Dec 2026 (estimated)
- First posted
- 7 Jul 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.
Add-Vacc is an unblinded cluster-randomised trial (CRT) with two arms: (i) the national HPV vaccination programme (girls aged ~14 years, control arm) and (ii) the national programme plus single-dose male HPV vaccination given to a multi-year cohort of boys (intervention arm). The CRT will be conducted in 26 communities/clusters (13 per arm) in northern Tanzania. Boys aged 14 to 18 years in the intervention arm will receive one dose of the 4-valent HPV vaccine (Gardasil®) that protects against HPV 6, 11, 16, and 18. Population genital HPV prevalence in 18 to 21-year-olds will be compared between intervention clusters (female and male vaccination) and control clusters (female vaccination only) at 3 years after the intervention. Blood sampling for immune responses and adverse event data collection will be performed in a subset of 200 male subjects in selected intervention clusters.
Study design
- Primary purpose
- Prevention
- Allocation
- Randomised
- Intervention model
- Parallel groups
- Masking
- Single blind (outcomes assessor)
- Number of arms
- 2
- Model description
- Cluster randomised trial with 26 communities (13 per arm)
| Arm | Type | Receives |
|---|---|---|
| Male vaccination + national HPV vaccination programme | Experimental | Biological: Gardasil® HPV vaccineSingle dose of the 4-valent HPV vaccine (Gardasil®; Merck \& Co.) offered to all eligible boys aged 14 to 18 years in the 13 intervention communities. Girls aged 14 years are offered 2 doses of Gardasil® through the Tanzanian national HPV vaccine programme |
| National HPV vaccination programme only | Active comparator | Biological: Gardasil® HPV vaccineGirls aged 14 years are offered 2 doses of Gardasil® through the Tanzanian national HPV vaccine programme |
Who may qualify
- Ages
- 14 to 18 years
- Sex
- Male only
- Healthy volunteers
- Accepted
- Age groups
- Child, Adult
Key inclusion criteria (6 listed)
- Parents and adult male participants (aged 18 years) must sign an ICF and male participants aged less than 18 years must sign an informed assent form (IAF), indicating that they understand the purpose of and procedures required for the study and are willing to participate in the study and to receive HPV vaccination. If the parent or participant cannot read or write, the procedures must be explained and informed consent/assent must be witnessed by a literate third party who is not involved in the conduct of the study.
- Participants must have been born male, and must be aged 14 to 18 years inclusive at time of vaccination.
- Participants must be living in an intervention community (cluster).
- Participants must be willing and able to comply with the protocol requirements.
- Participants must agree to avoid all non-trial immunisations in the 14 days following vaccination with the trial vaccine, other than emergency vaccinations such as post-exposure rabies or tetanus vaccinations.
Key exclusion criteria (6 listed)
- They have previously been vaccinated against HPV.
- They have a history of allergy or anaphylaxis to one or more of the HPV vaccine components, to yeast or to latex.
- They are enrolled in another vaccine research study that specifically specifies that they must not participate in a study of another vaccine
- They have been diagnosed with a chronic condition (except HIV, as per the comment above), such as an autoimmune condition, sickle cell disease, degenerative disease, neurologic or genetic disease, among others;
- There are significant conditions or clinically significant findings for which, in the opinion of the investigator, participation would not be in the best interest of the participant (e.g., it would compromise their safety or well-being).
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 |
|---|---|---|
| Gardasil® HPV vaccineAlso: 4-valent HPV vaccineSingle dose 4-valent HPV vaccine in males. Gardasil®, manufactured by MSD, consists of a licensed prophylactic virus-like particle (VLP) vaccine that protects against 4 HPV genotypes (HPV 6, 11, 16, 18). | Biological | Male vaccination + national HPV vaccination programme, National HPV vaccination programme only |
Primary outcome
Impact of adding single-dose male HPV vaccination to the national HPV vaccination programme in girls on population 4-valent HPV genotype prevalence in 18 to 21-year-old females and males
Time frame: Month 36
Prevalence of 4-valent vaccine HPV genotype DNA (HPV 6, 11, 16 or 18) in males and females aged 18 to 21 years in intervention clusters and control clusters 36 months post-male vaccination
5 secondary outcomes
Immunogenicity and safety of single dose 4-valent HPV vaccination in boys
Time frame: Month 12, 24 and 36
Impact of female-only vaccination through the national vaccination programme on population HPV prevalence in 18 to 21-year-old males and females
Time frame: Month 36
Uptake of dose 1 and coverage of dose 2 in eligible target groups for the national HPV vaccination programme;
Time frame: Month 36
Acceptability of a gender-neutral approach to HPV vaccination
Time frame: Month 24
Cost-effectiveness of adding a multi-year single dose male HPV vaccination strategy to the national female HPV vaccination programme
Time frame: Month 36
Results and safety
This study is still under way. Results are not available in the source record yet.
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 8 Sep 2026.
- Derived from this study: PubMed 41276263Bergman H, Henschke N, Arevalo-Rodriguez I, Buckley BS, Crosbie EJ, Davies JC, Dwan K, Golder SP, Loke YK, Probyn K, Petkovic J, Villanueva G, Morrison J. Human papillomavirus (HPV) vaccination for the prevention of cervical cancer and other HPV-related diseases: a network meta-analysis. Cochrane Database Syst Rev. 2025 Nov 24;11(11):CD015364. doi: 10.1002/14651858.CD015364.pub2.
- Individual participant dataSharing planned: Undecided
Related trials for HPV Infection
Not yet recruitingPhase 1/2
Clinical Trial to Assess the Safety, Tolerability, Reactogenicity, and Immunogenicity of a 10 Valent Human Papillomavirus Virus (10vHPV) Vaccine
Human Papillomavirus Infection
Active, not recruitingPhase 4
Comparing Immune Response of 2 vs 3 HPV Doses (27-45 Years Old)
Immunization, HPV Infection
Not yet recruitingPhase 2
Combination Bevacizumab and PRGN-2012 in Adults With Recurrent Respiratory Papillomatosis (RRP)
Respiratory Recurrent Papillomatosis (RRP), Human Papillomavirus (HPV)
RecruitingPhase 2
A Study of the Preliminary Efficacy of DARE-HPV to Treat High-risk Persistent Human Papillomavirus (hrHPV)
Human Papilloma Virus (HPV), High-risk Human Papillomavirus Infection
RecruitingPhase 2
A Single Arm Phase II Trial in p16-positive Oropharynx Cancer of Selective Dose De-escalation of nodAl VolumEs at Minimal Risk and Primary Site Disease (SAVED)
Head and Neck Cancer, Head and Neck Squamous Cell Cancer
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.
Deborah Watson-Jones, MD, PhD contact
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 Gardasil® HPV vaccine in people with HPV Infection and Vaccine Preventable Disease, run by London School of Hygiene and Tropical Medicine at 1 site in Tanzania.
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 6 inclusion and 6 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: looking for participants now, as of the sponsor's last update on 8 Sep 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 Tanzania. 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?
This study is still under way. Results are not available in the source record yet.
How can a doctor refer a patient or contact the research team?
Contact Deborah Watson-Jones, MD, PhD (deborah.watson-jones@lshtm.ac.uk), or a site near the patient. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
Impact of adding single-dose male HPV vaccination to the national HPV vaccination programme in girls on population 4-valent HPV genotype prevalence in 18 to 21-year-old females and males (time frame: Month 36). 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 NCT04953130, which also lists 1 linked publication.
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 8 Sep 2026.