Platelets for Neonatal Transfusion - study 2

The PlaNet-2 study is now complete.

Chief investigators: Dr Simon Stanworth and Dr Anna Curley
Primary sponsor: NHSBT
Funder: NHSBT


A trial assessing clinically relevant outcomes in relation to the platelet count thresholds commonly used as triggers for transfusion has never been undertaken in preterm neonates with severe thrombocytopenia.

Practice in many neonatal units in the UK has seen the adoption of thresholds for prophylactic platelet transfusions at around 20 to 30 x109/L, but the effectiveness and safety of any thresholds in preterm neonates has not been established in randomised controlled trials.

In the only randomised controlled trial to assess a threshold level for the effectiveness of neonatal prophylactic platelet transfusions, the platelet count thresholds were 50 and 150 x109/L (Andrew et al, 1993), but this trial excluded neonates with platelet counts < 50 x109/L.

Study hypothesis

PlaNeT-2 aims to assess whether a higher prophylactic platelet transfusion threshold is superior to the lower thresholds in current standard practice in reducing the proportion of patients who experience a major bleed or death up to study day 28.

This trial will help define optimal platelet transfusion support for severely thrombocytopenic preterm neonates by evaluating the risks and benefits of two different prophylactic neonatal platelet transfusion thresholds highlighted by the PlaNeT-1 study.

If superiority is demonstrated, then it would have an important influence on clinical practice. If superiority is not demonstrated for a higher platelet count threshold, the potential benefits of the lower threshold in neonatal practice include fewer transfusions, reduced donor exposure, reduced risk of platelet transfusion related adverse effects (including errors in processing and administration), and reduced costs.

Study design

Platelets for Neonatal Transfusion is a two-stage, randomised, parallel group, superiority trial, which follows on from a prospective multicentre observational study of platelet transfusion practice in neonates (PlaNeT-1 study; Stanworth et al, 2009).

PlaNet-2 compares clinical outcomes in preterm neonates randomised to receive prophylactic platelet transfusions to maintain platelet counts at or above either 25 x109/L or 50 x109/L. An interim analysis to assess trial feasibility and re-calculate the sample size will be conducted after 100 patients have completed the study period for the primary outcome.

Study contact


Venkatesh V, Curely A, Khan R, Clarke P, Watts T, Josephson C, Muthukumar P, New H, Seeney F, Morris S & Stanworth S. A novel approach to standardised recording of bleeding in a high risk neonatal population. Arch Dis Child Fetal Neonatal Ed 2013; 98: F260-3 [E Pub 09 Nov 2012 doi: 10.1136/archdischild-2012-302443]

PLANET-2 Curley A, Venkatesh V, Stanworth S, Clarke P, Watts T, New H, Willoughby K, Khan R, Muthukumar P, Deary A. Platelets for neonatal transfusion - study 2: a randomised controlled trial to compare two different platelet count thresholds for prophylactic platelet transfusion to preterm neonates. Neonatology, 2014;106(2):102-6. [E Pub 15 May 2014 doi: 10.1159/000358481].

K Willoughby, J May, A Curley. Improving recruitment in neonatal research trials – A practical guide. J Neonatal Nursing 2015 21, 241-247.

Curley A, Stanworth SJ, Willoughby K, Fustolo-Gunnink SF, Venkatesh V, Hudson C, Deary A, Hodge R, Hopkins V, Lopez Santamaria B, Mora A, Llewelyn C, D'Amore A, Khan R, Onland W, Lopriore E, Fijnvandraat K, New H, Clarke P, Watts T; PlaNeT2 MATISSE Collaborators. Randomized Trial of Platelet-Transfusion Thresholds in Neonates. New England Journal Medicine. 2018 Nov 2. doi: 10.1056/NEJMoa1807320.

Estcourt LJ. Platelet transfusion thresholds in premature neonates (PlaNeT-2 trial). doi: 10.1111/tme.12587