Stem cell-based interventions for the prevention and treatment of germinal matrix-intraventricular haemorrhage in preterm infants.

BACKGROUND: Germinal matrix-intraventricular haemorrhage (GMH-IVH) remains a substantial issue in neonatal intensive care units worldwide. Current therapies to prevent or treat GMH-IVH are limited. Stem cell-based therapies offer a potential therapeutic approach to repair, restore, and/or regenerate injured brain tissue. These preclinical findings have now culminated in ongoing human neonatal studies.
OBJECTIVES: To determine the benefits and harms of stem cell-based interventions for prevention or treatment of germinal matrix-intraventricular haemorrhage (GM-IVH) in preterm infants. SEARCH
METHODS: We used the standard search strategy of Cochrane Neonatal to search the Cochrane Central Register of Controlled Trials (CENTRAL; 2019, Issue 1), in the Cochrane Library; MEDLINE via PubMed (1966 to 7 January 2019); Embase (1980 to 7 January 2019); and the Cumulative Index to Nursing and Allied Health Literature (CINAHL) (1982 to 7 January 2019). We also searched clinical trials databases, conference proceedings, and reference lists of retrieved articles for randomised controlled trials and quasi-randomised trials. SELECTION CRITERIA: We attempted to identify randomised controlled trials, quasi-randomised controlled trials, and cluster trials comparing (1) stem cell-based interventions versus control; (2) mesenchymal stromal cells (MSCs) of type or source versus MSCs of other type or source; (3) stem cell-based interventions other than MSCs of type or source versus stem cell-based interventions other than MSCs of other type or source; or (4) MSCs versus stem cell-based interventions other than MSCs. For prevention studies, we included extremely preterm infants (less than 28 weeks' gestation), 24 hours of age or less, without ultrasound diagnosis of GM-IVH; for treatment studies, we included preterm infants (less than 37 weeks' gestation), of any postnatal age, with ultrasound diagnosis of GM-IVH. DATA COLLECTION AND ANALYSIS: For each of the included trials, two review authors independently planned to extract data (e.g. number of participants, birth weight, gestational age, type and source of MSCs, other stem cell-based interventions) and assess the risk of bias (e.g. adequacy of randomisation, blinding, completeness of follow-up). Primary outcomes considered in this review are all-cause neonatal mortality, major neurodevelopmental disability, GM-IVH, and extension of pre-existing non-severe GM-IVH. We planned to use the GRADE approach to assess the quality of evidence. MAIN
RESULTS: Our search strategy yielded 769 references. We did not find any completed studies for inclusion. One randomised controlled trial is currently registered and ongoing. Five phase 1 trials are described in the excluded studies. AUTHORS'
CONCLUSIONS: Currently no evidence is available to show the benefits or harms of stem cell-based interventions for treatment or prevention of GM-IVH in preterm infants.