Public call for data on diagnostic accuracy on nucleic acid amplification tests to detect TB and resistance to selected anti-TB agents

Public call for data on diagnostic accuracy on nucleic acid amplification tests to detect TB and resistance to selected anti-TB agents

Nucleic acid amplification tests (NAAT) are promising technologies for the rapid and accurate detection of TB and resistance to selected anti-TB agents. In December 2020, the World Health Organization (WHO) will convene a Guidelines Development Group (GDG) meeting to update its diagnostic guidelines on the use of NAATs to detect TB and resistance to selected anti-TB agents. Ahead of this meeting, WHO will commission reviews of relevant evidence on diagnostic accuracy for several NAAT assays.

The following NAAT assays or classes of NAAT assays will be discussed by the GDG:

Centralized assays that present end-to-end solutions for detection of TB and resistance to rifampicin and isoniazid (cDST: Index test 1);

Cartridge-based technology for isoniazid and second-line drug resistance detection (XDR cartridge: Index test 2);

Hybridization-based technology for pyrazinamide resistance detection (PZA LPA: Index test 3).

To enable this process, WHO is issuing a public call for data, appealing to industry, researchers, national TB programmes and other agencies to provide suitable evidence for the performance of these technologies. The obtained data will be essential to facilitate the process of WHO policy updates.

Please send relevant data by 1st August 2020, to [email protected]. For more information on the parameters of the datasets, variables, and the process see below:

Annex 1: Data requirements

Index test 1: Centralized assays that present end-to-end solutions for detection of TB and resistance to rifampicin and isoniazid (cDST platforms).

Desirable characteristics of the test: (a) Sample preparation workflow included; (b) Automated DNA extraction; (c) Automated PCR preparation; (d) Automated result interpretation; (c) Capacity per run: ≥24 tests; (d) Time from sample to full MDR-TB diagnosis: <12 hours; (e) Minimal desirable drug resistance detection: at least to INH and RIF.

Study type: Clinical evaluation studies to confirm diagnostic performance on clinical samples.

Study population: Random sample of unselected patients with signs and symptoms of TB, requiring evaluation for TB and/or resistance to isoniazid and rifampicin in sites of intended use.

Reference standard: At a minimum, result of a single sputum culture and phenotypic DST, wherever applicable (liquid or solid, with speciation) should be included for each result of Index test 1. The use of a genotypic sequencing results where available will have an added value to confirm the presence of mutations in addition to phenotypic DST results.

Index test 2: Cartridge-based technology for isoniazid and second-line drug resistance detection (XDR cartridge);

Desirable characteristics of the test: (a) Automated real-time PCR; (b) Automated result interpretation; (b) Capacity per run: ≥ 4 tests; (c) Time test results: <4 hours; (d) Minimal desirable drug resistance detection: at least to INH and FQ.

Study type: (a) Analytical validation studies measuring accuracy, precision, and reproducibility of the test in contrived specimens or panels, covering all key mutations to isoniazid and second-line drugs. (b) Clinical evaluation studies to confirm diagnostic performance on clinical samples.

Study population: Patients with detected TB, requiring evaluation for resistance to isoniazid and second-line anti-TB agents in sites of intended use.

Reference standard: At a minimum, result of a single sputum phenotypic DST (liquid or solid, with speciation) should be included for each result of Index test 2. The use of a genotypic sequencing results where available will have an added value to confirm the presence of mutations in addition to phenotypic DST results.

Index test 3: Hybridization-based technology for pyrazinamide resistance detection (PZA LPA).

Desirable characteristics of the test: (a) Automated or manual hybridization methodology; (b) Automated or manual result interpretation (c) Time from sample to test results: <24 hours; (d) Minimal desirable drug resistance detection: at least to PZA.

Study type: (a) Analytical validation studies measuring accuracy, precision, and reproducibility of the test in contrived specimens or panels, covering all key mutations to pyrazinamide; (b) Clinical evaluation studies to confirm diagnostic performance on clinical samples;

Study population: Patients with detected TB and resistance to rifampicin, requiring evaluation for resistance to pyrazinamide in sites of intended use;

Reference standard: At a minimum, result of a single sputum phenotypic DST (liquid or solid, with speciation) should be included for each result of Index test 3. The use of a genotypic sequencing results where available will have an added value to confirm the presence of mutations in addition to phenotypic DST results.

Source link