Post-market review of HIV nucleic acid tests

We have completed a post-market review of NATs intended to screen, diagnose, and monitor HIV, to investigate concerns raised regarding the risk of false positive results in individuals undertaking chimeric antigen receptor (CAR) T-cell therapy.

Outcomes of the post market review are published below.

Background of the review

We received signals about false positive HIV NAT results in individuals that have undergone CAR T-cell therapy.

CAR T-cell therapy is a new advanced treatment that uses a person’s own immune cells (T-cells) and alters them to target certain blood cancers that do not respond to more traditional forms of treatment. Several CAR T-cell therapeutics are approved for use and included in the Australian Register of Therapeutic Goods (ARTG).

As part of a patient’s management plan, they may be tested for various infectious diseases including HIV. Due to the cross-reactivity between some HIV NATs and CAR T-cell therapies, there is a risk of a patient receiving a false positive HIV test result, particularly if this risk is not clearly identified in the Instructions for Use (IFU) for the laboratory-trained personnel. Alternative tests for HIV antigens or antibodies can be used to identify false positives, as these are not affected by the cross-reactivity. It is important to note that CAR T-cell therapy does not carry the risk of HIV infection.

The purpose of the review was to identify if any of the HIV NATs included in the ARTG are at risk of false positive results due to reactivity with CAR-T therapy and work with manufacturers of affected HIV NATs, to update their IFU to identify the risk of cross-reactivity, if applicable.

We required all sponsors of HIV NATs included in the ARTG to provide information to us about their devices, including:

• IFUs
• adverse events or complaints reported in Australia and overseas related to cross-reactivity with CAR-T cell therapy
• the manufacturer’s analysis of cross-reactivity of the NAT with common viruses
• the manufacturer’s risk management plan in identifying manufacturer’s monitoring process and protocol for evaluation of cross-reactivity
• the manufacturer’s risk mitigation activities planned or undertaken.

Post-market review: outcomes and actions

We have reviewed the evidence provided by the sponsors and manufacturers of all HIV NATs included in the ARTG.

As an outcome of the review, the appropriate risk mitigation was determined to be an update to the IFUs to include additional warnings about the risk of false positive HIV test results in patients receiving CAR T-cell therapy. This outcome was communicated to sponsors and they were instructed to amend their IFUs, so that the updated information can be communicated to customers and laboratory personnel.

Information for consumers and healthcare professionals

Consumers that are currently or have previously undertaken CAR T-cell therapy should consult their treating health practitioner if they have any concerns regarding the safety or performance of HIV NAT devices or test results and discuss alternative testing options such as antigen/antibody tests or repeating tests on another NAT platform.

Reporting problems

Consumers and health professionals are encouraged to report problems with medical devices. Your report will contribute to the TGA's monitoring of these products. For more information see the TGA Incident Reporting and Investigation Scheme (IRIS).

We cannot give advice about an individual's medical condition. You are strongly encouraged to talk with a health professional if you are concerned about a possible adverse event associated with a medical device.

Devices included in the review

The HIV NATs that were included in the post-market review, and associated actions and outcomes, are listed below:

Note: Recall actions can be found by searching the Database of Recalls, Product Alerts and Product Corrections.