Trial Review

Technical difficulties have been reported by some users of the search function and is being investigated by technical staff. Thank you for your patience and apologies for any inconvenience caused.

The safety and scientific validity of this study is the responsibility of the study sponsor and investigators. Listing a study does not mean it has been endorsed by the ANZCTR. Before participating in a study, talk to your health care provider and refer to this information for consumers
Trial registered on ANZCTR


Registration number
ACTRN12616000247471
Ethics application status
Approved
Date submitted
17/02/2016
Date registered
23/02/2016
Date last updated
1/02/2022
Date data sharing statement initially provided
20/02/2019
Date results information initially provided
20/02/2019
Type of registration
Prospectively registered

Titles & IDs
Public title
A double-blinded randomised controlled trial of daily use mouthwash to reduce the detection of pharyngeal gonorrhoea among men who have sex with men
Scientific title
Will daily use of mouthwash reduce the detection of pharyngeal gonorrhoea among men who have sex with men?
Secondary ID [1] 288506 0
None
Universal Trial Number (UTN)
Trial acronym
OMEGA (Oral Mouthwash use to Eradicate GonorrhoeA)
Linked study record

Health condition
Health condition(s) or problem(s) studied:
Gonorrhoea 297576 0
Condition category
Condition code
Infection 297769 297769 0 0
Sexually transmitted infections

Intervention/exposure
Study type
Interventional
Description of intervention(s) / exposure
Men will receive four 500mL bottles of study mouthwash (Mouthwash A) in a plain, clean and opaque bottle labelled with participant’s study ID. Mouthwash A contains 0% alcohol and is available in the supermarkets or chemists. All participants will be asked to rinse and garage 20 mL of the given mouthwash for 60 seconds at least once every day during the 12-week study period but no more than 5 times per day as per the product recommendation.

Adherence will be monitored by the self-admitted questionnaires and returning the mouthwash bottles at clinic visits week 6 and 12.
Intervention code [1] 293868 0
Prevention
Comparator / control treatment
Men will receive four 500mL bottles of study mouthwash (Mouthwash B) in a plain, clean and opaque bottle labelled with participant’s study ID. Mouthwash B contains 0% alcohol and is available in the supermarkets or chemists. All participants will be asked to rinse and garage 20 mL of the given mouthwash for 60 seconds at least once every day during the 12-week study period but no more than 5 times per day as per the product recommendation.

Adherence will be monitored by the self-admitted questionnaires and returning the mouthwash bottles at clinic visits week 6 and 12.
Control group
Placebo

Outcomes
Primary outcome [1] 297299 0
The proportion of MSM who test positive for pharyngeal gonorrhoea within 12 weeks.
Timepoint [1] 297299 0
At week 6 and 12.
Participants will be required to attend the clinic at week 6 and 12. Pharyngeal swabs will be taken by the clinicians at week 6 and 12, and participants will be required to post their self-collected saliva sample at week 3 and 9. The proportion of pharyngeal gonorrhoea positive is defined as any positive in any specimens within 12 weeks. Interim cases of pharyngeal gonorrhoea diagnosed outside of these four time points will also be included if they occur between 3 and 12 weeks. An example might include an individual who presents with acute symptomatic urethral gonorrhoea and who is also tested for pharyngeal gonorrhoea at this presentation.
Secondary outcome [1] 320653 0
Adherence to mouthwash over 12 weeks. This will be assessed using questionnaire. This questionnaire is designed by the principal investigator and has been reviewed and revised by several associate investigators.
Timepoint [1] 320653 0
At week 12.
Participants will be asked to complete a total of 5 paper-based questionnaires at week 0, 3, 6, 9, and 12, respectively. A long questionnaire will be provided to participants at week 0, 6, and 12, and a short version at week 3 and 9. The questionnaire includes basic demographic details, general information on use of mouthwash, sexual experiences, use of antibiotics, adherence and feedback of the study mouthwash, and diagnosis of gonorrhoea. The one-page short version of questionnaire will take approximately 1-2 minutes to complete; while the long version of questionnaire will take approximately 5-10 minutes to complete.
Secondary outcome [2] 320654 0
The proportion of MSM with other sexually transmitted infections (HIV, syphilis, rectal gonorrhoea, rectal chlamydia, urethral gonorrhoea, urethral chlamydia, pharyngeal chlamydia) within 12 weeks.
Timepoint [2] 320654 0
At week 12.
Participants will be required to attend the clinic at week 12. Urine, throat swabs and anal swabs will be taken by the clinicians for gonorrhoea and chlamydia screening. Blood will be taken for HIV and syphilis serology.
Secondary outcome [3] 320655 0
Acceptability of using mouthwash daily as an intervention to prevent pharyngeal gonorrhoea. This will be assessed using questionnaire. This questionnaire is designed by the principal investigator and has been reviewed and revised by several associate investigators.
Timepoint [3] 320655 0
At week 12.
Participants will be required to complete a questionnaire.

Eligibility
Key inclusion criteria
1. Men who self-report having sex with another man and aged 16 years or above.
2. Men who fulfil one of the following criteria:
(a) Aged 16-24 years old, tested positive or negative for pharyngeal gonorrhoea by nucleic acid amplification test (NAAT) detection or treated 30 days prior to the enrolment ; OR
(b) Aged 25 years or above, tested positive for pharyngeal gonorrhoea by nucleic acid amplification test (NAAT) detection or treated 30 days prior to the enrolment.
3. Men who provide consent to contact their GP to clarify the use and name of antibiotics over the 12-week study period .
4. Men who have sufficient English language proficiency to understand the requirements of the study and complete the questionnaire.
5. Men who are willing and able to complete the study procedures.
6. Men who are able to provide written informed consent to the study.
Minimum age
16 Years
Maximum age
No limit
Sex
Males
Can healthy volunteers participate?
Yes
Key exclusion criteria
1. Men who will be away for more than 3 weeks within the next 12 weeks.
2. Men who report known contraindications to use mouthwash or food dye such as allergy.
3. Men who report use of long-term use of antibiotics for more than 4 weeks.
4. Men who use mouthwash regularly and are not willing to only use the study mouthwash within the next 12 weeks.
5. Transgender individuals.
6. Men who have previously enrolled in the OMEGA study.
7. Men who are not able to provide consent to contact their GP to clarify the use and name of antibiotics over the 12-week study period.
8. Men who have a member living in the household is on the OMEGA study.

Study design
Purpose of the study
Prevention
Allocation to intervention
Randomised controlled trial
Procedure for enrolling a subject and allocating the treatment (allocation concealment procedures)
This is a double-blind, controlled RCT study. A trial biostatistician, who has no clinical input into the trial, will generate and hold the random number sequence. The randomisation sequence will be computer generated using a small block size.
Methods used to generate the sequence in which subjects will be randomised (sequence generation)
A randomisation ratio of 1:1 will be used, with no stratification. The randomisation list will be used to label the two trial mouthwash with a study identification number (SIN). Eligible participants who consent will be allocated to their randomised arm and will be given the next available SIN which will then define their study treatment. If any participants withdraw from the trial before receiving any study treatment, their SIN will not be reused. Only the trial biostatistician will be aware of which mouthwashes are interventions and which are controls, and only the trial biostatistician will have access to whether individual participants are on the intervention or control arm. Participants, clinicians, research nurses, and other trial staff will not know which mouthwash the participant is randomised to. The sequence will be generated by computer software (i.e. Stata).
Masking / blinding
Blinded (masking used)
Who is / are masked / blinded?
The people receiving the treatment/s
The people administering the treatment/s
The people assessing the outcomes
Intervention assignment
Parallel
Other design features
No
Phase
Not Applicable
Type of endpoint/s
Efficacy
Statistical methods / analysis
Data will be analysed in Stata. The primary analysis will be an intention to treat analysis for all those with at least once follow up swab.

Primary analysis: The primary end point will be the proportion of men who have gonorrhoea detected in the pharynx or saliva by any method at 3, 6, 9 or 12 weeks or at any time between 3 and 12 weeks outside of these 4 tests. The proportion of men with pharyngeal gonorrhoea detected will be summarised using exact binomial confidence internals. The two study arms will be compared using logistic regression. While randomisation should ensure balance of baseline characteristics, if there are any differences in baseline characteristics, including age, follow-up time and sexual behaviours throughout trial, a logistic regression will be performed to adjust for these factors.

Secondary analysis: A sensitivity analysis will also be performed comparing treatment arms in terms of gonorrhoea detection at 3, 6, 9 or 12 weeks using repeated measures logistic regression methods. A secondary analysis will also be undertaken for those who have adhered to high levels of mouthwash use. The number of days using mouthwash will be calculated for each participant, and summarised by treatment arm as median and interquartile range. A high level adherence to mouthwash will be defined as men who use a mouthwash more than 50% of the time over the 12-week period (i.e. use a mouthwash for at least 42 days). Although our pilot data showed that the adherence of mouthwash was more than 90% but it was over a 14-day period, we hypothesized that this proportion may drop to 50% over a 12-week period.

We have therefore powered the trial to detect a 50% reduction in the gonorrhoea detection rate from 20% in the 'control' arm to 10% in the 'treatment' arm. To detect this reduction with 80% power would require 438 men to be randomised (219 to each arm), with continuity corrections. To allow for up to 15% loss of follow up, we will recruit a total of 504 men, 252 in each group.


Recruitment
Recruitment status
Completed
Date of first participant enrolment
Anticipated
1/03/2016
Actual
31/03/2016
Date of last participant enrolment
Anticipated
29/12/2017
Actual
27/07/2018
Date of last data collection
Anticipated
30/04/2019
Actual
26/10/2018
Sample size
Target
504
Accrual to date
Final
530
Recruitment in Australia
Recruitment state(s)
NSW,VIC
Recruitment postcode(s) [1] 18397 0
2001 - Sydney
Recruitment postcode(s) [2] 18398 0
2050 - Camperdown
Recruitment postcode(s) [3] 18396 0
2150 - Parramatta
Recruitment postcode(s) [4] 12718 0
3053 - Carlton
Recruitment postcode(s) [5] 18395 0
3068 - Fitzroy North

Funding & Sponsors
Funding source category [1] 292857 0
Government body
Name [1] 292857 0
National Health and Medical Research Council
Country [1] 292857 0
Australia
Primary sponsor type
Hospital
Name
Alfred Health
Address
55 Commercial Rd, Melbourne VIC 3004
Country
Australia
Secondary sponsor category [1] 291601 0
None
Name [1] 291601 0
Address [1] 291601 0
Country [1] 291601 0

Ethics approval
Ethics application status
Approved
Ethics committee name [1] 294391 0
Alfred Hospital Human Research Ethics Committee
Ethics committee address [1] 294391 0
The Alfred, PO Box 315, Prahran Victoria 3181
Ethics committee country [1] 294391 0
Australia
Date submitted for ethics approval [1] 294391 0
19/01/2016
Approval date [1] 294391 0
12/02/2016
Ethics approval number [1] 294391 0
29/16

Summary
Brief summary
Men who have sex with men tested positive for pharyngeal gonorrhoea at Melbourne Sexual Health Centre (MSHC) who volunteer will be randomised to rinse and gargle the study mouthwash every day within the next 12 weeks. The primary outcome is the proportion of MSM with diagnosed with pharyngeal gonorrhoea within 12 weeks.
Trial website
www.mshc.org.au/omega
Trial related presentations / publications
Public notes

Contacts
Principal investigator
Name 63406 0
A/Prof Eric Chow
Address 63406 0
Melbourne Sexual Health Centre,
580 Swanston Street, Carlton, VIC 3053, Australia
Country 63406 0
Australia
Phone 63406 0
+613-9341-6233
Fax 63406 0
Email 63406 0
echow@mshc.org.au
Contact person for public queries
Name 63407 0
Ms Kate Maddaford
Address 63407 0
Melbourne Sexual Health Centre,
580 Swanston Street, Carlton, VIC 3053, Australia
Country 63407 0
Australia
Phone 63407 0
+613-9341-6243
Fax 63407 0
Email 63407 0
KMaddaford@mshc.org.au
Contact person for scientific queries
Name 63408 0
A/Prof Eric Chow
Address 63408 0
Melbourne Sexual Health Centre,
580 Swanston Street, Carlton, VIC 3053, Australia
Country 63408 0
Australia
Phone 63408 0
+613-9341-6233
Fax 63408 0
Email 63408 0
echow@mshc.org.au

Data sharing statement
Will individual participant data (IPD) for this trial be available (including data dictionaries)?
No
No/undecided IPD sharing reason/comment
This is not covered by the current ethics application.


What supporting documents are/will be available?




Results publications and other study-related documents

Documents added manually

Documents added automatically
SourceTitleYear of PublicationDOI
EmbaseCould antiseptic mouthwash inhibit pharyngeal Neisseria gonorrhoeae ? Further research is required.2017https://dx.doi.org/10.1136/sextrans-2017-053139
EmbaseNew thinking on gonorrhoea control in MSM: Are antiseptic mouthwashes the answer?.2018https://dx.doi.org/10.1097/QCO.0000000000000421
EmbaseA multicentre double-blind randomised controlled trial evaluating the efficacy of daily use of antibacterial mouthwash against oropharyngeal gonorrhoea among men who have sex with men: The OMEGA (Oral Mouthwash use to Eradicate GonorrhoeA) study protocol.2017https://dx.doi.org/10.1186/s12879-017-2541-3
EmbaseAntiseptic mouthwash for gonorrhoea prevention (OMEGA): a randomised, double-blind, parallel-group, multicentre trial.2021https://dx.doi.org/10.1016/S1473-3099%2820%2930704-0
EmbaseThe Impact of Mouthwash on the Oropharyngeal Microbiota of Men Who Have Sex with Men: a Substudy of the OMEGA Trial.2022https://dx.doi.org/10.1128/spectrum.01757-21
Dimensions AIThe development of mouthwashes without anti-gonococcal activity for controlled clinical trials: an in vitro study2020https://doi.org/10.12688/f1000research.20399.2
Dimensions AIAge, ethnic and travel-related disparities in kissing and sexual practices among heterosexual men in Melbourne, Australia2020https://doi.org/10.1071/sh19230
Dimensions AIPharyngeal Gonorrhoea: The Willingness of Australian Men Who Have Sex with Men to Change Current Sexual Practices to Reduce Their Risk of Transmission—A Qualitative Study2016https://doi.org/10.1371/journal.pone.0164033
N.B. These documents automatically identified may not have been verified by the study sponsor.