Plain English Summary
Background and study aims
Chronic hypertension (high blood pressure) affects 2% of pregnancies and is associated with significant risks for both mother and baby. There is a 1 in 4 chance that complications will arise in pregnancy (pre-eclampsia (diabetes during pregnancy) and/or fetal growth restriction) requiring a preterm delivery. Oral L-citrulline is an amino acid supplement which has been associated with an improvement in blood pressure and blood vessel function. In a phase I study of 24 obese pregnant women, three weeks treatment of L-Citrulline (3g/day) was associated with a significant reduction in blood pressure, which persisted after the treatment had ceased until the end of pregnancy. There was also a marked change in factors involved in blood vessel function, which are altered in pregnancies complicated by placental dysfunction, at several time points over pregnancy. This suggests a potential beneficial effect of oral L-citrulline on placental and/or vessel function. The potential use of an amino acid supplement, which is safe, readily available and of relatively low-cost, represents an appealing intervention for the long-term management of chronic hypertensive diseases, especially in pregnancy where the number of treatment options might be more limited, and non-pharmacological interventions are more acceptable. At present, there is no information regarding either the efficacy or acceptability of L-citrulline supplementation to modulate cardiovascular function in women with chronic hypertension in early pregnancy. The aim of this study is to assess the acceptability and feasibility of using L-citrulline supplements for women with chronic hypertension to then plan a larger study, which to determine whether oral L-citrulline treatment is cost-effective for the treatment of chronic hypertension.
Who can participate?
Women aged 18 and older who are 12-16 weeks pregnant who have high blood pressure.
What does the study involve?
Participants are randomly allocated to one of two groups. Those in the first group receive a supplement with amino acid L-citrulline twice per day for a maximum of 10 weeks around 14-22 weeks of pregnancy. Those in the second group receive a placebo (dummy) supplement for 10 weeks around 14-22 weeks of pregnancy. Participants are follow up until 12 weeks post giving birth to measure their blood pressure.
What are the possible benefits and risks of participating?
Participation in this study could help lower blood pressure in hypertensive pregnant women. There are no risks associated with participation.
Where is the study run from?
1. St Mary’s Hospital Manchester (UK)
2. St Thomas’s Hospital London (UK)
When is the study starting and how long is it expected to run for?
September 2012 to January 2019
Who is funding the study?
National Institute for Health Research (UK)
Who is the main contact?
Miss Sophie Hennessy
cherry.trial@liverpool.ac.uk
Trial website
Contact information
Type
Public
Primary contact
Miss Sophie Hennessy
ORCID ID
Contact details
Clinical Trials Research Centre
University of Liverpool
Institute of Child Health
Alder Hey Children's NHS Foundation Trust
Liverpool
L12 2AP
United Kingdom
+44 1517949765
cherry.trial@liverpool.ac.uk
Additional identifiers
EudraCT number
2015-005792-25
ClinicalTrials.gov number
Protocol/serial number
35351
Study information
Scientific title
CHronic HypERtension and L-citRulline studY: Feasibility study on the effects of L-citrulline on uteroplacental and cardiovascular function in hypertensive pregnant women
Acronym
CHERRY
Study hypothesis
Study aims:
The aims of the present study are
1. Determine the effect of L-citrulline supplementation on maternal blood pressure in women with chronic hypertension
2. Determine whether L-citrulline supplementation can improve uterine blood flow and other markers associated with adverse pregnancy outcomes
Hypothesis:
The hypothesis that tight blood pressure control in early pregnancy has a favourable impact on placental development such that the risk of subsequent placental dysfunction is lower. In addition, the beneficial effects on the vascular endothelium of L-Citrulline may impact on the interaction between the placental trophoblast cells and the maternal spiral arteries improving invasion and ultimately placentation.
Ethics approval
North West Haydock REC, 14/09/2016, ref: 16/NW/0557
Study design
Randomised; Interventional; Design type: Treatment, Prevention, Dietary
Primary study design
Interventional
Secondary study design
Randomised controlled trial
Trial setting
Home
Trial type
Treatment
Patient information sheet
Not available in web format, please use the contact details below to request a patient information sheet
Condition
Specialty: Reproductive health and childbirth, Primary sub-specialty: Reproductive and Sexual Medicine; UKCRC code/ Disease: Reproductive Health and Childbirth/ Respiratory and cardiovascular disorders specific to the perinatal period
Intervention
Treatment across arms are double blinded with only the trial pharmacist at site and randomising statistician being unblinded. Randomisation is done via a secure web based system and is performed by a member of the research team at site. Once randomisation has occurred an automated blinded email is sent to all relevant members of the research team and an unblinded email is sent to the pharmacist.
Group 1: Participants receive supplementation with the amino acid L-citrulline (3g twice per day) from 14±/-2 to 22±/-2 weeks’ gestation (maximum of 10 weeks treatment duration).
Group 2: Participants receive supplementation with the placebo from 14±/-2 to 22±/-2 weeks’ gestation (maximum of 10 weeks treatment duration).
The women are followed up until 12 weeks post-delivery to measure blood pressure.
Intervention type
Other
Phase
Phase II
Drug names
Primary outcome measure
1. Recruitment rate is measured by number of women recruited and completing study per month
2. Change in diastolic blood pressure (from baseline to 8 weeks post randomisation following L- citrulline supplementation, compared with placebo – Change in clinic diastolic BP (average of 3 readings) will be calculated at baseline and week 8
Secondary outcome measures
1. Acceptability of intervention in pregnant women with chronic hypertension is measured by number of women completing treatment and completion of participant questionnaire at end of the treatment period
2. The following results are compared within treatment groups only (paired analysis) as the study is not sufficiently powered to identify a difference between randomised groups:
2.1. Average day and night time Ambulatory Blood Pressure Measurements (ABPM.) ABPM measurements will be downloaded from the software (SpaceLabs) and the day and night time averages calculated by the software.
2.2. Pulse wave velocity measurements will be exported from the Tensioclinic software. Vascular compliance measurements including central BP, pulse wave velocity, augmentation index will be compared within groups.
2.3. Peripheral vascular resistance measurements obtained from the NICOM. Measurements of cardiac output, cardiac index, SVI and TPRI will be compared within groups.
2.4. Uteroplacental blood flow measurements: uterine artery resistance index (RI) and pulsatility index (PI), presence/absence of notching
2.5. Plasma ADMA/arginine concentrations
2.6. Change in antihypertensive therapy
Overall trial start date
12/09/2012
Overall trial end date
04/01/2019
Reason abandoned (if study stopped)
Eligibility
Participant inclusion criteria
1. Viable singleton pregnancy
2. Gestation: 12+0 to 16+0 weeks
3. Aged 18 years or over
4. Able to provide informed consent
5. Diastolic BP of ≥90 mmHg (average of two clinic readings) OR ≥80 mmHg if taking antihypertensive medication OR PWV ≥9m/s before 16 weeks’ gestation
6. Serum creatinine <120 mmol/l at booking
Participant type
Patient
Age group
Adult
Gender
Female
Target number of participants
Planned Sample Size: 42; UK Sample Size: 42
Participant exclusion criteria
There is no exclusion criteria.
Recruitment start date
04/07/2017
Recruitment end date
01/03/2018
Locations
Countries of recruitment
United Kingdom
Trial participating centre
St Mary’s Hospital Manchester
Oxford Road
Manchester
M13 9WL
United Kingdom
Trial participating centre
St Thomas’s Hospital London
Westminster Bridge Road
Lambeth
London
SE1 7E
United Kingdom
Funders
Funder type
Government
Funder name
National Institute for Health Research
Alternative name(s)
NIHR
Funding Body Type
government organisation
Funding Body Subtype
Federal/National Government
Location
United Kingdom
Funder name
Wellcome Trust
Alternative name(s)
Wellcome
Funding Body Type
private sector organisation
Funding Body Subtype
international
Location
United Kingdom
Results and Publications
Publication and dissemination plan
Planned publication in a peer-reviewed high impact journal.
IPD saring statement:
The data sharing plans for the current study are unknown and will be made available at a later date.
Intention to publish date
04/01/2020
Participant level data
To be made available at a later date
Basic results (scientific)
Publication list