HTAC Guidance: Self-Administered Antigen Test Kits (SAAgT) | Health Technology Assessment Division

Published on: August 25, 2022

The HTAC and its review of health technologies

To ensure equitable access to quality and affordable health care to Filipinos, the Health Technology Assessment Council (HTAC) was created under the Universal Healthcare Act of 2019 (Republic Act No. 11223). The HTAC provides technical guidance on the optimal use of health technologies including clinical equipment and devices (i.e., medical devices, radiation devices, and health-related devices). Through its recommendations, the HTAC is able to guide the financing and coverage decisions of the DOH and PhilHealth.

What are Self-Administered Antigen Test (SAAgT) Kits?

The Philippine FDA which issued a special certification for the use of SAAgTs and the RITM which did the validation prior to FDA approval defined the Self-Administered Antigen Test (SAAgT) as a “test which can be performed by non-healthcare professionals or lay users in home, non-hospital, or non-laboratory settings.” SAAgT has become a popular testing method. It is cheaper, readily-accessible, easy-to-use, and has a faster turnaround time although it is not as reliable as the reverse transcription polymerase chain reaction (RT-PCR) test especially if the test is done by an untrained individual. It should be emphasized though that the sensitivity of SAAgTs can increase by training users or providing them with detailed but easy-to-understand instructional materials.

The World Health Organization (WHO) recognizes SAAgT as a complement but not as a replacement for other testing methods done by trained providers such as rapid antigen test (RAgT) or RT-PCR. The WHO issued its interim guidance on the use cases of SAAgT on 09 March 2022.

What is the recommendation of HTAC on SAAgT?

On 28 June 2022, the Secretary of Health (SOH) approved the Health Technology Assessment Council (HTAC) recommendation to finance SAAgT kits for the following:

Diagnosis of suspect and probable cases among people with high risk of developing severe COVID-19 and needing the immediate provision of antiviral drugs (symptomatic and asymptomatic with close contacts)
Screening and diagnosis of healthcare workers

While the HTAC recommends the use of SAAgTs, it maintains that RT-PCR should be the standard diagnostic test for COVID-19, pending the availability of new evidence.

The HTAC recommendations are aligned with the WHO recommendations for the use of SAAgT found in the interim guideline of WHO dated 09 March 2022. It is also important to always correlate the test results with the overall clinical and epidemiological context (e.g., history of exposure). Individuals with a high index of suspicion and who tested negative using SAAgT should be isolated until they can be confirmed through a repeat SAAgT after 24-48 hours (WHO, 2022; CDC, 2021; TGA Australia, 2021).

If the repeat test is positive, isolate and manage as COVID-19 case;
If the repeat test is still negative and the patient is:
- Symptomatic, perform confirmatory RT-PCR testing immediately;
- Asymptomatic, release from quarantine and follow minimum public health standards

For individuals with positive SAAgT results (positive for COVID-19), it is recommended that they be isolated and managed as COVID-19 cases.

It should be emphasized that these recommendations are interim and that the HTAC is actively following the latest evidence which is rapidly evolving. When necessary, the HTAC shall update its recommendation as new information becomes available.

What is the basis of the HTAC recommendation?

Based on evidence, the following are the characteristics of SAAgT:

Responsiveness to Disease Magnitude, Severity, and Equity

Since the beginning of the COVID-19 pandemic, multiple guidelines on testing for SARS-CoV 2 (which is the virus that causes COVID-19) have been developed. One of these is on the use of rapid antigen test kits (RAgT) as a supplement to RT-PCR testing (DC 2020-0160), or for diagnosing close contacts (DM 2020-0468). Initially in 2020, only the Research Institute for Tropical Medicine (RITM) and 5 subnational hospitals were allowed to do COVID-19 testing, but since then the number has increased to 331 testing laboratories nationwide as of April 2022.

Administrative Order No. 2020-0014 or the Guidelines in Securing a License to Operate a COVID-19 Testing Laboratory in the Philippines enabled an increase in the country’s capacity for COVID-testing though the licensing of private and government COVID-19 testing laboratories, whether hospital-based or non-hospital-based, in an effort to ensure the safety of personnel and the general public, as well as the quality and accuracy of the generated reports of COVID-19 testing laboratories. There were also other government efforts to increase COVID-19 testing capacity such as the use of GeneXpert machines which can detect SARS-CoV 2 in real time, and the “Swab Cab” of the Office of the Vice President which provided free mobile RAgT services.

Although RT-PCR remains the standard diagnostic test for COVID-19 in the Philippines, the limited capacity of the country in performing laboratory-based tests due to the stringent and costly requirements of RT-PCR testing led to the search for other diagnostic or screening methods.

Safety and Effectiveness

The FDA, which is primarily in charge of the performance of validation and technical review of applicant products for COVID Testing including SAAgTs, authorized 13 importers to distribute six brands of SAAgTs for use, as of 22 March 2022.

The overall pooled sensitivity (the capacity of a test to identify patients with the disease being tested) of SAAgTs was 82.0% while its overall pooled specificity (the capacity of a test to identify patients without the disease being tested) was 100.0%. These are within the 80% sensitivity and 97% specificity requirement of RITM.

Household Financial Impact

In purchasing SAAgTs in the Philippine market, households will incur out-of-pocket costs in addition to medical consultation and transportation costs, unless PhilHealth, DOH or other government entities finance these kits.

Currently, PhilHealth only covers RT-PCR testing, Rapid Antigen Testing, and Antibody Testing, according to Philhealth Circular 2022-0003. As of January 2022, the DOH has set the price cap of SAAgT kits at Php 350.00 per DOH Department Circular 2021-0323.

Affordability and Viability

SAAgT had the lowest unit cost per test kit compared to RT-PCR and RAgT.
- For testing A1, A2, and A3 populations: Php 9.2 B to Php 30.32 B for SAAgTs
- For surveillance of A1 population only: Php 5.96 B to Php 23.85 B for SAAgTs;
- For testing of vulnerable groups A2 + A3 only: : Php 3.24 B to Php 6.47 B for SAAgTs
The total cost of the initial and possible repeat testing using the SAAgT kit should not exceed the government price cap for Self Administered Rapid Antigen Testing indicated in Department Circular 2021-0323-B.
The costing for the reporting system will be the same, regardless of whether positive and/or negative results are reported.

Acceptability

Focus Group Discussions (FGDs) were conducted by HTA Philippines, which involved participants from different groups, such as health care workers, at-risk patient groups, economic frontliners, and micro, small and medium enterprises (MSMEs), and academic institutions, to determine acceptability, to optimize the use of the test kits, and to ensure more efficient access of the stakeholders to kits.
The participants stressed that the use of SAAgTs can be acceptable if it is implemented in a community-centered, grassroots-based approach; if it is more accessible for GIDAs and rural areas; and if its delivery is equitable.
During the conduct of a literature review, it was found that, for conformity in self-testing, educational attainment as a predictor of compliance, gender-based preferences and sociocultural differences in self-testing, and workload reduction in health facilities were some of the major factors in self-testing.

What are the suggestions of HTAC on SAAgT?

In the implementation of SAAgTs, the HTAC suggests the following to the DOH:

To regulate distribution through Barangay Health Stations in areas with high and/or increasing cases and increasing use of healthcare equipment and facilities for the populations indicated in its recommendation;
The HTAC recommends for DOH to implement a reporting system for both positive and negative results. All results should be reported to the Barangay Health Emergency Response Team (BHERT) or healthcare providers. The implementation and action on this recommendation for a reporting system is within the purview of the DOH.
To publicize standards on diagnostic performance in all COVID-19 testing kits, and to update this on a regular basis (e.g., once a month).
To strengthen the system for monitoring and evaluation of compliance of manufacturers to regulatory standards and post-marketing requirements;
To emphasize that testing (using RAgTs or NAATS) should be used in addition to other health measures such as minimum public health standards, physical distancing, ventilation, quarantining/isolation, symptom-based screening and contact tracing.
Used self-administered antigen test kits shall be disposed of as household waste and shall be properly sealed in a plastic bag.

Although the HTAC highly suggests these actions, it is up to the DOH if they will follow these or implement these in their guidelines, as they have more knowledge on the current challenges in implementation, which are outside of HTAC’s purview.

What else should I know about SAAgT?

Contents of the test kit package

It is desirable that self-administered rapid antigen test kits contain all materials and accessories necessary for the procedure (i.e., nasal swab, collection tube, test cassette, etc.)

User instructions

Based on DOH DM 2022-0033, manufacturers, suppliers, and distributors shall develop references for appropriate use for the general public that shall include:

Instructions for use that are readable, user-friendly, and simplified to provide adequate guidance to the lay public on the test kit’s proper administration, interpretation of results, and disposal.
A step-by-step video guide specific to the antigen kit for easy reference of the public, and references and links submitted to the DOH for public posting.
A Filipino-language translation of the reference materials in plain language format, and preferably with other additional regional language translations, if available.

How long is the testing if one uses SAAgT?

The use of SAAgT usually takes around 30 minutes from sample collection to results.