Genetic Testing in Newborns Moves From Rare to Routine Application

Genedrive kit for detecting single nucleotide polymorphism m.1555A>G in neonates and their mothers: a systematic review and cost-effectiveness analysis

Background

Neonates with suspected sepsis are commonly treated with gentamicin, an aminoglycoside. These antibiotics are associated with high risk of ototoxicity, including profound bilateral deafness, in people with the m.1555A>G mitochondrial genetic variant.

Objective

This early value assessment summarised and critically assessed the clinical effectiveness and cost-effectiveness of the Genedrive MT-RNR1 ID Kit for identifying the gene m.1555A>G variant in neonates and mothers of neonates needing antibiotics or anticipated to need antibiotics. Following feedback from the scoping workshop and specialist assessment subgroup meeting, we also considered the Genedrive MT-RNR1 ID Kit for identifying the m.1555A>G variant in mothers prior to giving birth.

Data sources

For clinical effectiveness, we searched three major databases in October 2022: MEDLINE, EMBASE and CINAHL (Cumulative Index to Nursing and Allied Health Literature). For cost-effectiveness, in addition to the three mentioned databases we searched Cochrane and RePEc-IDEAS.

Study selection

Study selection and risk-of-bias assessment were conducted by two independent reviewers (Ryan PW Kenny and Akvile Stoniute for clinical effectiveness and Hosein Shabaninejad and Tomos Robinson for cost-effectiveness). Any differences were resolved through discussion, or by a third reviewer (Nick Meader).

Study appraisal

Risk of bias was assessed using Quality Assessment of Diagnostic Accuracy Studies-2. One study (n = 751 neonates recruited) was included in the clinical effectiveness review and no studies were included in the cost-effectiveness review. All except one outcome (test failure rate: low risk of bias) were rated as being at moderate risk of bias. The study reported accuracy of the test (sensitivity 100%, 95% confidence interval 29.2% to 100%; specificity 99.2%, 95% confidence interval 98% to 99.7%), number of neonates successfully tested (n = 424/526 admissions), test failure rate (17.1%, although this was reduced to 5.7%), impact on antibiotic use (all those with a m.1555A>G genotype avoided aminoglycosides), time taken to obtain a sample (6 minutes), time to genotyping (26 minutes), time to antibiotic treatment (55.18 minutes) and the number of neonates with m.1555A>G (n = 3).

Limitations

The economic component of this work identified key evidence gaps for which further data are required before a robust economic evaluation can be conducted. These include the sensitivity of the Genedrive MT-RNR1 ID Kit for identifying the gene m.1555A>G variant in neonates, the magnitude of risk for aminoglycoside-induced hearing loss in neonates with m.1555A>G, and the prevalence of the m.1555A>G variant. Other potentially important gaps include how data regarding maternal inheritance may potentially be used in the clinical pathway.

Conclusions

This early value assessment suggests that the Genedrive MT-RNR1 ID Kit has the potential to identify the m.1555A>G variant and to be cost-effective. The Genedrive MT-RNR1 ID Kit dominates the current standard of care over the lifetime, as it is less costly and more effective. For a 50-year time horizon, the Genedrive MT-RNR1 ID Kit was also the dominant strategy. For a 10-year time horizon, the incremental cost-effectiveness ratio was estimated to be £103 per quality-adjusted life-year gained. Nevertheless, as anticipated, there is insufficient evidence to conduct a full diagnostic assessment of the clinical effectiveness and cost-effectiveness of the Genedrive MT-RNR1 ID Kit in neonates directly or in their mothers. This report includes a list of research priorities to reduce the uncertainty around this early value assessment and to provide the additional data needed to inform a full diagnostic assessment, including cost-effectiveness modelling.

Study registration

This study is registered as PROSPERO (CRD42022364770).

Funding

This award was funded by the National Institute for Health and Care Research (NIHR) Evidence Synthesis programme (NIHR award ref: NIHR135636) and is published in full in Health Technology Assessment; Vol. 28, No. 75. See the NIHR Funding and Awards website for further award information.