TGA Updates Guidance on IVD Self-Tests for Chlamydia, Gonorrhoea and Syphilis
The Therapeutic Goods Administration, TGA, has updated its guidance on performance requirements for in vitro diagnostic self-tests for chlamydia, gonorrhoea and syphilis.
The guidance provides manufacturers and sponsors with the TGA’s expectations on clinical performance requirements, including clinical sensitivity and specificity, as well as risk mitigation measures for these IVD self-tests.
Scope and Purpose
The guidance applies to IVD medical devices intended to be used as self-tests for Chlamydia trachomatis, Neisseria gonorrhoeae and Treponema pallidum.
The document identifies key risks that must be mitigated and notes that conditions may be imposed on self-test kits included in the Australian Register of Therapeutic Goods, ARTG.
The TGA also clarifies that analytical performance and stability studies are not addressed in detail in the guidance, although robust analytical performance evidence remains critical to demonstrating overall safety and performance.
Public Health Context
The guidance highlights that sexually transmitted infections, including chlamydia, gonorrhoea and syphilis, remain a significant public health issue in Australia, with notification rates increasing over the last decade.
The TGA notes that legal supply of these self-tests may improve access to testing, including in regional and remote areas, and may help reduce delays in testing and support earlier access to intervention and treatment.
Clinical Performance Expectations
The guidance states that self-tests for serious diseases should demonstrate a high standard of clinical performance relative to their intended purpose and classification.
It also emphasizes that IVD self-tests must be designed and manufactured to perform appropriately for lay users, taking into account user skills, available means and variations in technique and environment.
For chlamydia and gonorrhoea self-tests, clinical performance studies should generally be prospective and representative of the intended user population, including appropriate consideration of age, sex, symptoms, geographic and clinical settings.
Minimum Performance Requirements
For chlamydia and gonorrhoea self-tests, the TGA states that devices must meet minimum clinical performance requirements across relevant specimen types, including:
overall clinical sensitivity of at least 95%;
overall clinical specificity of at least 99%.
For syphilis self-tests, the guidance states that devices must meet minimum clinical performance requirements across relevant specimen types, including finger-stick whole blood:
clinical sensitivity of at least 95%;
clinical specificity of at least 98%.
The guidance also states that contrived samples are not acceptable for determining clinical sensitivity and specificity for these self-tests.
Usability Studies for Lay Users
Because chlamydia, gonorrhoea and syphilis self-tests are intended to be performed by lay users, manufacturers must provide usability studies demonstrating that the device performs as intended in the hands of these users.
The TGA states that study populations should be representative of the intended user population in the Australian context, including demographics, health literacy and people for whom English is not the preferred language. Participants with prior medical or laboratory training should be excluded.
Usability studies are expected to address user comprehension, inter-reader variability, invalid test rate and user sensitivity/specificity studies.
Key Risks and Risk Mitigation
The guidance identifies general risks associated with STI self-testing, including user-related errors, incorrect specimen collection, failure to follow instructions, misinterpretation of results and failure to seek appropriate follow-up.
For chlamydia and gonorrhoea self-tests, the TGA highlights risks related to specimen quality, early testing, asymptomatic individuals and incorrect specimen collection. The guidance also notes that rapid antigen self-tests are not intended to replace clinical assessment or laboratory testing.
For syphilis self-tests, the guidance highlights the limitations of antibody-based testing, including the inability to distinguish active infection from previously treated infection, reinfection, infectious status or disease progression without confirmatory laboratory testing and clinical assessment.
IFU Requirements
The guidance sets out detailed expectations for the instructions for use, or IFU, including clear information on what the kit is testing for, intended user population, limitations, simple instructions for performing and interpreting the test, clinical sensitivity and specificity, timing of use, false-negative risks and follow-up requirements.
The IFU should also clearly indicate that chlamydia, gonorrhoea and syphilis self-testing is for presumptive screening only and that users with positive results should consult a medical practitioner for confirmatory laboratory testing and treatment advice where required.
Post-Market Monitoring
Sponsors of self-tests included in the ARTG have ongoing responsibilities under Australian legislation and the Therapeutic Goods Advertising Code.
These include facilitating inspections, providing device samples upon request, making technical documentation available, ensuring advertising compliance, and reporting certain incidents, performance issues and overseas regulatory actions to the TGA.
The TGA may also impose additional conditions, such as user support requirements, regular annual reporting and specified distribution channels, depending on the residual risks identified for the device.
Impact on IVD Manufacturers and Sponsors
For IVD manufacturers and sponsors seeking ARTG inclusion for chlamydia, gonorrhoea or syphilis self-tests, the updated guidance reinforces the need for robust clinical evidence, lay-user usability evidence and clear risk mitigation.
Manufacturers and sponsors should pay particular attention to:
prospective clinical performance study design;
minimum sensitivity and specificity thresholds;
specimen type claims and specimen equivalence;
representative intended-use populations;
usability studies with lay users;
user comprehension and result interpretation;
invalid test rates;
risks linked to false-negative and false-positive results;
confirmatory testing and medical follow-up;
IFU clarity, language accessibility and warnings;
post-market monitoring and reporting obligations;
possible additional ARTG conditions.
For IVD self-test developers, the key message is that access to STI self-testing may support public health objectives, but only where devices demonstrate strong clinical performance, safe lay-user operation and effective lifecycle risk controls.
