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Does vascular endothelial growth factor gene therapy safely improve outcome in severe early-onset fetal growth restriction?

Final Report Summary - EVERREST (Does vascular endothelial growth factor gene therapy safely improve outcome in severe early-onset fetal growth restriction?)

Executive Summary:
Severe, early onset fetal growth restriction (FGR) affects 11,000 babies annually in the EU. In most cases, reduced maternal uterine blood flow restricts nutrient and oxygen delivery to the fetus causing fetal growth to slow or cease. There are no therapies that improve fetal growth in the womb. Current management of FGR involves very preterm delivery of the fetus (before 28 weeks of gestation), before death occurs in utero, with the aim of minimising irreversible organ damage, particularly to the brain. This adds additional risks to the baby from extremely preterm birth, with its own attendant short and long-term complications. Affected neonates suffer intracranial haemorrhage, chronic lung disease, cerebral palsy, with heart disease and diabetes as adults. Furthermore FGR may be detected while the fetal weight is far below 500g, a situation considered by many to be non-viable. From cohort studies and local data, we estimate that the cumulative stillbirth/morbidity/neonatal mortality rate in pregnancies affected by severe early onset FGR is between 75-80%.

At the start of the EVERREST project there was strong pre-clinical evidence that an adenovirus vector gene therapy delivered to the mother would treat FGR. This pioneering maternal vascular endothelial growth factor (VEGF) gene therapy treatment is designed to be administered to the uterine arteries of pregnant women who are affected by this serious condition; gene therapy would not be given to the fetus. The VEGF gene therapy seeks to promote increased delivery of nutrients and oxygen to the placenta by increasing maternal luterine blood supply. The treatment is intended to benefit the mother and her fetus by reducing the chance of perinatal loss and the burden of disease and disability due to FGR after birth, through increasing fetal growth rate during pregnancy.

During the first half of the project, the adenovirus vector was manufactured by an industrial partner SME according to Good Manufacturing Practice (GMP) standards. The potential for drug spread across the human placental barrier from the mother to the fetus was tested out by exposing the maternal side of cultured human placentas after birth to very high doses of the GMP vector. The detailed studies showed that the vector did not markedly affect human placental integrity and function in the laboratory, and there was limited tissue access and transfer of vector across the placental barrier. Subsequently a reproductive toxicology study conducted to Good Laboratory Practice (GLP) standards was completed, using the specific VEGF-D adenovirus vector developed for the clinical trial. The study assessed the safety of the drug and established the dose to be used in the clinical study.

The EVERREST Consortium has performed an extensive bioethics programme of research, engaging with a variety of international parent associations, advocacy groups, disability groups, midwife and medical associations. Respondents had a generally favourable view of the ethics and social acceptability of the trial, and there were no legal concerns. During the project an Independent Ethics Advisory Board reviewed all aspects of the results generated during the program to ensure the highest ethical standards have been adhered to.

During the project, maternal VEGF gene therapy for placental insufficiency leading to FGR was granted European Medicines Agency (EMA) orphan status after the EVERREST Consortium demonstrated that it is a rare, life threatening or chronically debilitating and currently untreatable disease affecting 3.33 per 10 000 EU population (95% CI 3.07–3.60).

The Clinical Trial protocol designed by the Consortium is now ready to be submitted for approval by regulatory and ethical authorities. A 6 year prospective observational study of pregnant women who have severe early onset FGR has collected a rich dataset from over 120 participants on maternal, fetal and neonatal outcomes up to two years of age. This has allowed the development of improved counselling about pregnancy prognosis for affected couples. Data from this study has been used to refine the final clinical trial inclusion criteria and the dose escalation regimen. The participant centres will work during 2019 to be ready to start recruiting patients once the clinical trial is approved.
Project Context and Objectives:
Fetal Growth Restriction (FGR) is a major obstetric problem globally that affects up to 8% of all pregnancies. In this condition, the fetus fails to achieve its genetically determined growth potential and is born far smaller than anticipated. The causes are heterogeneous. In a minority there are structural abnormalities of the fetus, aneuploidy, congenital viral infection or maternal medical disorders (approximately 10% of cases). More commonly impaired uteroplacental function restricts delivery of nutrients to the fetus resulting in slowing or even cessation of fetal growth.
FGR is an important cause of perinatal mortality. It contributes to death in over 50% of antepartum stillbirths, approximately 1.46 million fetuses worldwide/year, which was highlighted by a Lancet series on Stillbirths. With effective fetal screening many babies are delivered preterm due to concerns about fetal or maternal health. Pre-eclampsia is associated with FGR in one third of cases. Early onset pre-eclampsia (<34 weeks of gestation) affects 1 in 200 pregnancies and leads to severe maternal hypertension, proteinuria and multi-organ dysfunction; it is a global cause of substantial perinatal and maternal morbidity and mortality. Early prevention has proved elusive; there is no treatment.
Amongst babies born preterm around 25% of births are early inductions or elective deliveries because of concerns about fetal growth. Preterm birth is an important public health issue and causes increased neonatal, childhood and adult mortality and morbidity. It is a worldwide issue – the first World Prematurity Day on November 17th 2011 drew international attention to this. On the 23rd November 2011 the European Foundation for the Care of Newborn Infants launched the “Call to Action for Newborn Health” at the European Parliament, to improve the care of pregnant women and newborn babies by persuading EU institutions and national governments to invest in perinatal care and research about preterm birth. Additionally, the European Critical Care Foundation met in October 2010 to develop a European consensus statement on decision-making in extremely preterm birth, which is a common consequence of fetal growth restriction.
In the most severe cases of FGR (approx 1:500 fetuses), fetal growth slows in the middle trimester and delivery or fetal death occurs before 28 weeks of gestation, termed severe early onset FGR. Such fetuses are usually detected first at the detailed ultrasound scan performed in mid-pregnancy (20-24 weeks of gestation) that is offered to all women in the EU. There are currently no proven screening methods for FGR and, following identification, there are no therapies that improve fetal growth in utero. Thus, current management is to deliver the fetus before death occurs in utero with the aim of minimising irreversible organ damage, particularly to the brain. This adds additional risks to the baby from extremely preterm birth, with its own attendant short and long-term complications. Furthermore FGR may be detected while the fetal weight is far below 500g, a situation considered by many to be non-viable. From cohort studies and local data, we estimate that the cumulative stillbirth/morbidity/neonatal mortality rate in pregnancies affected by severe early onset FGR is between 75-80%.
Recent data on neonatal intensive care show improved survival of preterm FGR infants, but at great cost. Survival studies suggest however, that even modest increases in birthweight (e.g from 500 to 600g) and gestation at delivery (e.g from 26 to 27 weeks) are associated with significant improvements in mortality and morbidity. The risk benefit ratio is such that an antenatal therapy that led to even a small increase in fetal growth, gestation at delivery, or survival in utero is likely to improve outcome, with major health and economic benefits. In an EU and US multi-centre observational study of babies born after severe early onset FGR, median survival gained per day in utero between 24 and 27 weeks of gestation was 2% (range 1.1 – 2.6).
This proposal was to develop a highly innovative new therapy in the field of obstetrics, a specialty in which there is currently a lack of investment in new treatments. The consortium consisted of two technical SMEs (FINV now renamed Trizell, and MI that was subsequently left the consortium at month 54) and a university (UEF) with experience in taking gene medicines to market, five academic health science centres across the EU (UCL, UKE, IDIBAPS, ULUND and UCLH) that are experts in managing pregnancies complicated by severe early onset FGR, and a leading centre in the bioethics of prenatal therapy (QMSoL). We also recruited a project management company experienced in FP6, FP7 projects (EURAM, active from months 1 to 54), which activities from month 63 were fulfilled by an innovation company (INNV) with experience of FP6, FP7 and H2020, large scale collaborative project administration and financial management. Our aim was to translate a novel gene medicine delivered to pregnant women, into the clinic, so as to improve fetal growth in severe early onset FGR.
Context for this project
The collaboration: In 2006 a successful academic-industrial collaboration was established between University College London (UCL), London, UK, a leading institution in gene therapy research, and Ark Therapeutics Group Plc, London, UK, a pharma company that had a major focus on VEGF vascular therapeutics and experience of translating gene therapeutics into humans. The aim was to explore the possibility of treating FGR with local maternal uterine artery VEGF gene therapy. In 2006 initial pilot pre-clinical experiments performed by Professor Anna David (UCL), the project lead, demonstrated that local VEGF gene transfer to the maternal uteroplacental circulation using adenovirus vectors containing the VEGF-A165 gene (Ad.VEGF-A165) increased uterine blood flow, reduced constriction of uterine arteries and increased angiogenesis. Further pre-clinical studies in 2008 using this same vector confirmed that a long-term effect on uterine blood flow could be achieved, supporting the concept that VEGF gene therapy could improve fetal growth. Related pre-clinical experiments have studied a clinical grade Ad.VEGF-DΔNΔC vector showing similar results to the Ad.VEGF-A165 vector. In 2009, the collaboration was awarded a Wellcome Trust project grant for a large study in a pre-clinical FGR model which has a close correlation between reduced uterine blood flow and restricted fetal weight. Within 2 years, the collaboration had shown proof of principle, that uterine artery injection of Ad.VEGF-A165 improves fetal growth. In the last two years a similar project in another pre-clinical FGR model has shown again that local uteroplacental VEGF gene therapy improves fetal growth and have higher birthweight with no safety concerns for the mother or offspring.
Meetings with the regulatory authorities, the EMA CHMP GTWP (European Medicines Agency, Committee for Medicinal Products for Human Use, Gene Therapy Working Party) in 2007 and UK MHRA (Medicines and Healthcare products Regulatory Agency) in 2008 where the proposed toxicology programme and the phase I/IIa safety/efficacy study was discussed were positive, and encouraged the collaboration to begin pre-clinical toxicology studies. Even at that stage, it was realised that a phase I/IIa trial was likely to need to be implemented in the EU to access a sufficiently large number of women affected by severe early onset FGR. In September 2012, Ark Therapeutics re-structured its business to focus solely upon the generation of revenue from its viral development and manufacturing services based in Kuopio, Finland. In March 2013, Ark Therapeutics changed its name to FinVector Vision Therapies Limited and during 2016, Finvector Vision Therapies Limited was part of a restructuring process and became Trizell Ltd, a beneficiary within the project.

Having shown proof of principle for efficacy, the next step to achieve clinical translation was to identify potential EU partners with strong backgrounds in severe early onset FGR, who could provide access to the number of women required for the first-in-woman trial. Discussions with potential EU partners were held at European conferences where data was presented, and the EVERREST consortium was defined. A key reason for this proposal was to obtain the grant funding necessary to bring the treatment past the toxicology and initial clinical stages that typically constitute very high risks of commercial failure for new therapeutics.

Prenatal Therapy: Research developing clinically applicable prenatal gene and cell therapies began at UCL Institute for Women’s Health in 1998, with the aim of curing genetic disease before birth. Funded by a 5 year UK Medical Research Council Programme Grant from 2000, the collaboration between Fetal Medicine (Professor Charles Rodeck, University College London, London, UK) and the Gene Therapy Research Group (Professor Charles Coutelle, Imperial College, London, UK) studied pre-clinical translation of prenatal gene therapy. Professor David (UCL) was awarded a PhD in 2005 in Fetal Medicine on this programme grant, in collaboration with other members of the consortium (Peebles). In 2006 the Prenatal Cell and Gene Therapy Group was established at UCL, led by David, with the aim of “developing prenatal treatments for severe and life-threatening disorders using gene and cellular therapy, and to investigate the efficacy, safety and ethical issues of such treatment”. The Group are international leaders in the field of prenatal gene therapy and its translation into woman. The EVERREST consortium was thus underpinned by a committed collaboration that has an established track record of developing and delivering innovative perinatal and adult gene and cellular therapies.

The aim of the EVERREST project was to translate a novel therapy for FGR from bench to bedside by developing the first clinically applicable evidence based therapy that could improve perinatal outcome in severe early onset FGR. The project had three key objectives:
1) To complete a pre-clinical reproductive toxicology programme to include analysis of the biodistribution of the adenoviral vector after injection into the maternal uterine artery and intense examination for any possible exposure of the fetuses to the vector, or any effects on their prenatal or postnatal development.
2) To review the literature on gene therapy, experimental treatment of pregnant women and fetal medicine research to clarify the ethical, legal and regulatory issues relevant to the conduct of the EVERREST clinical trial, and to evaluate the ethical and social acceptability of the EVERREST trial and intervention in couples affected by severe early onset FGR and a wide range of stakeholder groups across the EVERREST partner member states.
3) To perform an uncontrolled, open-label, dose finding Phase I/II (to mother and baby) study in 15 and up to 27 pregnancies affected by severe early onset FGR, at four centres of excellence in the EU, of VEGF in an adenoviral vector, delivered to the maternal uterine artery using minimally invasive techniques to show (a) safety and tolerability, and (b) efficacy by improving the reduction in uterine blood flow by 50%, when compared to historical data from untreated pregnancies affected by severe early onset FGR. Exploratory end-points of fetal growth and gestational age at delivery, and a composite outcome for fetal and neonatal mortality and serious morbidity were to be studied and compared with historical cohort data.

Project Results:
The EVERREST project aimed to develop a groundbreaking gene therapy to treat severe early-onset fetal growth restriction. If successful, this would be the first treatment available in the world for this condition.
The project has gone through many stages in order to reach its ultimate objective of developing a clinical trial protocol to test the safety and efficacy of maternal gene therapy designed with the contribution of all members of the Consortium. The treatment seeks to promote increased delivery of nutrients to the placenta by increasing uterine blood supply and is designed to be administered to pregnant women (rather than the fetus) who are affected by this serious condition.
The EVERREST consortium has made good progress towards each of its objectives during the project and is poised to submit an application for ethical and regulatory approval.

Bioethics Study
The objective of this part of the work was to review the literature on gene therapy, experimental treatment of pregnant women and fetal medicine research to clarify the ethical, legal and regulatory issues relevant to the conduct of the EVERREST clinical trial, and to evaluate the ethical and social acceptability of the EVERREST trial and intervention in approximately 100 couples affected by severe early onset FGR and a wide range of stakeholder groups across the EVERREST partner member states.
As conclusions from the literature review it can be said that there is no objection of ethical, legal or regulatory principle to the intervention under development in the EVERREST programme and there is no objection of ethical, legal or regulatory principle to a trial of this intervention in pregnant women, provided that the regulatory authorities are happy to issue a clinical trial certificate in light of the final preclinical studies. But ultimately, the final ethical evaluation of the intervention, and the trial, depends upon how far pregnant women suffering from fetal growth restriction are willing and able to make the decision to undergo the intervention.
After the literature review work, the EVERREST project performed an extensive ethics study by conducting interviews and surveys to the project main stakeholders and also patients. Interviews were performed amongst key stakeholders, patient organisations/advocacy groups and NGO type organisations and medical organisations conducted in the European partner member States and amongst European-level stakeholder groups. Patients who had experienced severe early onset FGR were also interviewed. Interviews evaluated the ethical and societal acceptability of vascular endothelial growth factor gene therapy in severe early-onset fetal growth restriction as a treatment given to women in pregnancy, where that pregnancy is affected by this very serious condition which has a significant risk of stillbirth or a very low birthweight baby.
The interviews were based on a semi-structured questionnaire of around 30 to 40 minutes’ duration. The questionnaires were designed taking account of the points discussed in the literature review and with input from the clinical investigators in the UK. All interviews were translated and transcribed into English in case of foreign language interviews and transcribed verbatim in case of English language interviews. Transcription and translation was carried out on an ongoing basis. All translations/transcriptions were cross-checked.
In total just over 70 respondent contacts were made. Respondents were informed that the interview aimed to discuss the ethics and social acceptability of a proposal for a gene therapy targeted for women with severe early growth restriction. All respondents were emailed a summary of the proposed trial (two different descriptions with differing complexity were used for the different stakeholder groups) as well as the link to the EVERREST project web page at The overall conclusion which can be drawn from these interviews is that respondents had a generally favourable view of the ethical and social acceptability of EVERREST. Most pregnant women view their unborn child as a person early on in pregnancy and would generally do anything to help this child.
While decision-making in a pregnancy affected by severe early-onset FGR was difficult, women did not feel incapable of arriving at a decision regarding any treatment options but would listen to the advice of healthcare professionals and discuss the options with their partners. Women were also generally interested in participating in clinical trials particularly where the trial conferred a potential benefit to the unborn child. The informed consent considerations did not seem to raise any different ethical concerns from other trials in pregnancy affecting the fetus with respect to the accuracy and adequacy of the information given to potential trial participants and the voluntariness of the consent. The women interviewed overall viewed the proposed EVERREST trial in positive terms and did not consider the issue of possible disability of their child due to prematurity as a reason not to participate. However, women would generally not want to expose themselves to serious risks. Neither the issue of the treatment being a form of gene therapy nor the administration of the therapy seemed to cause any major concern.

Clinical vector manufacture
The vector for use in the reproductive toxicology studies and in the clinical trial was manufactured specifically for the project by partner FinVector (subsequently Trizell Ltd) to GMP specifications. The manufactured Drug Substance was stored pending the results of the reproductive toxicology study before it could be vialled to Drug Product.

Toxicology studies
Two toxicology studies have been performed.
Analysis of a study in dual perfused human placentas was completed during the project. The perfusion experiments were conducted before the EVERREST started but the analysis for any evidence of vector spread across the placenta was performed during the project. The study was performed by the University of Manchester using a Ad.VEGF-DΔNΔC vector made by Ark Therapeutics. This study was discussed and agreed with the MHRA in 2009 (UK regulator), Paul Ehrlich Institute in 2012 (German regulator) and EMA in 2015, as a GLP-like appropriate study to investigate the potential reproductive toxic effect of the vector on the human placenta. These in vitro human placenta studies showed no detrimental effect or any toxic effects of the Ad.VEGF-DΔNΔC vector on the human placental integrity and function in vitro. CiToxLAB, a Contract Research Organisation in France completed the analysis as part of the EVERREST project. They demonstrated minimal transfer of vector across 8 human placentas (only 4 samples out of 116 samples tested positive for vector) with minimal signs of toxicity.
During the project, a formal pre-clinical reproductive toxicology study was conducted to Good Laboratory Practice standards using the specific clinical manufactured Ad.VEGF-DΔNΔC adenovirus vector developed by partner FinVector (subsequently Trizell Ltd). CiToxLAB, a Contract Research Organisation in France completed the study which assessed the safety of the Investigational Product and ultimately established the dose to be used in the clinical study. There were delays in this study due to the fact that this kind of pre-clinical toxicology study had never before been performed to GLP and the technique to deliver the vector had to be transferred from partner UEF to the CRO CiToxLAB. Once this was achieved however the study was conducted in a straightforward way and delivered robust results. These showed no evidence that the vector crossed the placenta to the fetus in the pre-clinical animal model, and that there was no evidence of harm.

Clinical study design (Prospective study)
The EVERREST Prospective Study was conducted at all four sites, recruiting women who have babies with an estimated fetal weight less than the 3rd centile between 20 and 26+6 weeks of pregnancy in the UK, Germany, Spain and Sweden. This providing contemporaneous data from untreated pregnancies affected by severe early onset FGR.
A database was created containing information about antenatal investigations, maternal complications, fetal outcome and neonatal progress. The detailed clinical database and biobank of samples which were collected as part of this study, included neurodevelopmental follow up for 2 years for surviving babies and children. This was linked to a biobank containing samples of maternal blood, umbilical cord, umbilical cord blood, placenta, placental bed and myometrium. These samples have been used to investigate the biological mechanisms which underlie severe early onset FGR and, in conjunction with the database, have been used to investigate potential biomarkers for fetal and neonatal outcome.
The EVERREST prospective observational study has revealed hitherto unknown characteristics of the cohort of women who would be eligible for participation in the EVERREST clinical trial. The data that these women have provided are important to know before undertaking a trial of a novel maternal adenovirus gene therapy where it is possible that the drug may lead to symptoms or signs that will need to be distinguished as related or unrelated to the trial ATMP.
The 6 year prospective observational study of pregnant women who have severe early onset FGR has collected a rich dataset from over 120 participants on maternal, fetal and neonatal outcomes up to two years of age. This has allowed the development of improved counselling about pregnancy prognosis for affected couples. Data from this study has been used to refine the final clinical trial inclusion criteria and the dose escalation regimen.

Orphan Drug Designation
During the project, maternal VEGF gene therapy for placental insufficiency leading to FGR was granted European Medicines Agency (EMA) orphan status after the EVERREST Consortium demonstrated that it is a rare, life threatening or chronically debilitating and currently untreatable disease affecting 3.33 per 10 000 EU population (95% CI 3.07–3.60). Orphan Drug status was secured under Regulation (EC) No 141/2000 of the European Parliament and of the Council. This was the first time that placental insufficiency and FGR has been designated as an orphan disease and is an important step forward for the field of pregnancy therapeutics.

Final Drug Product manufacture
Once the results of the reproductive toxicology studies were known, the vector Drug Product was vialled to the correct doses for the clinical trial and a stability testing programme was initiated. The coordinator, members of the Trial Team from UCL and Trizell Ltd met the MHRA for scientific advice regarding the final Drug Product in July 2018 and answered questions regarding the final dossier of manufacturing data. The Clinical Trial Protocol underwent minor amendments following the MHRA advice.

Phase I/IIa Clinical Trial Protocol
A clinical trial protocol is essential for the safe, valid conduct of any clinical research. A robust protocol is especially important in the context of the EVERREST Clinical Trial because this would be the first use of gene therapy in pregnancy, and because of the scarcity of early phase research in pregnancy.
The development of the EVERREST Clinical Trial protocol has been a multinational and multi-disciplinary exercise. The protocol has been written on the basis of the template and working documents provided by UCL CCTU (University College London Comprehensive Clinical Trials Unit). These are, in turn, based on an adaptation of the Medical Research Council CCTU protocol template (2012) and the Standard Protocol Items: Recommendations for Interventional Trials (SPIRIT) 2012 Statement for protocols of clinical trials. Throughout the development process there was regular input from the various disciplines within the EVERREST consortium, including fetal medicine, obstetrics, neonatology, and interventional radiology. The EVERREST Independent Ethics Advisory Committee (EAC), Data Safety Monitoring Board (DSMB), and Trial Steering Committee (TSC) were also formed and provided input into the protocol. The protocol has been finalised and has undergone evaluation and amendment by the Protocol Review Committee at the UCL Comprehensive Clinical Trials Unit. The final version will be submitted for ethical and regulatory approval in the next few months.
The promising results obtained encouraged the Consortium to keep developing the project to the stage of preparing a Clinical Trial protocol to take the treatment to women with the untreatable FGR condition.

Ethical Reviews
The EVERREST consortium underwent two EC ethical reviews during the project in January 2015 and April 2017. All documents related to projects requiring ethical approval, namely pre-clinical animal research and clinical research studies were reviewed by the European Commission. This included all research protocols, patient information sheets and consent forms, letters of approval from animal ethical review committees and national research ethics committees. There were no ethical concerns raised during these reviews.

The EVERREST Clinical Trial Application is now in its final review stage at UCL CCTU and its submission for ethical and regulatory review is now imminent. There have been delays along the long journey of the consortium, related to conduct of the reproductive toxicology studies which delayed final Drug Product manufacture. During this time however, the consortium has taken advantage of the time available to study women with severe early onset FGR as never before. The criteria for the clinical trial protocol that we have subsequently developed will allow us to select the optimal population of pregnant women with the disease, in whom to study the safety and efficacy of the novel gene medicine. Ultimately we hope that this potential treatment is found to be safe and effective so as to deliver the first therapeutic for fetal growth restriction.
Potential Impact:
1. Impact

Strategic impact

Based on information from the Eurostat website, the EU population has approximately 5.4 million live births each year. Of these, approximately 11,000 babies annually will be born after severe early onset FGR.
During the course of the project, results became available from 3 trials of sildenafil citrate (STRIDER UK, AUS/NZ and Dutch STRIDER trial). The first two trials showed no benefit of the therapy on fetal growth or wellbeing but also no harm; the third trial was terminated mid-way due to concerns about harm (increased death from pulmonary hypertension in the treated arm). There are no other therapies for FGR in development that have reached this stage of translation.

Death and quality of life: FGR has short and long term impact. Severely affected babies are more likely to die before or at the time of birth. Recent improvements in the perinatal and neonatal care of premature growth restricted babies have increased survival, but survivors need neonatal intensive care which is stressful for the baby, and costly for the parents and society. The immediate clinical impact of improving fetal growth in pregnancies complicated by severe early onset FGR will be a reduction in stillbirths, neonatal mortality and morbidity, and a fall in the cost of lifetime care.
Neonatal mortality is dependent on gestational age at delivery and birthweight for gestational age. With extremely low gestations and birthweight, regional cohorts and local figures show that mortality exceeds 50% (1;2). Even a small increase in fetal growth will substantially impact neonatal mortality. In a EU and US multi-centre observational study of neonates born after severe early onset FGR, median survival gained per day in utero between 24 and 27 weeks of gestation was 2% (range 1.1 – 2.6) (3). Additionally, the odds ratio for death per 100 g increase in birth weight after extreme preterm delivery (23 – 26 weeks of gestation) is estimated to be 0.6 (4).
Neonatal morbidity includes the range of complications of prematurity such as brain injury, chronic lung disease and retinopathy of prematurity, all of which are dependent on gestational age at birth. An increased risk of respiratory illness and chronic lung disease (5), neutropenia and sepsis are specifically associated with FGR (6). The fetal haemodynamic redistribution in FGR leads to ischaemic bowel problems such as necrotising enterocolitis, with the attendant mortality risk, need for surgery, short bowel syndrome and long term parenteral nutrition. Observational data from babies born after severe early onset FGR show that major morbidity reduces progressively from 56.6% to 10.5% as gestational age advances from 24 weeks to 32 weeks (3). Significant improvements in neonatal morbidity are therefore likely to result from quite modest increases in gestational age at delivery.
Childhood outcomes: Improved outcomes in terms of cognitive function, a reduction in special educational needs, improved behavioural and psychiatric outcomes will result from improved maturity at delivery and a reduction in neonatal morbidity as may be expected from successful treatment. These are important outcomes offsetting the initial costs of treatment. There are two further aspects to cost-savings that would also offset the initial treatment costs. Firstly there is evidence from systematic reviews that preschool children born preterm and at very low birth weight perform more poorly than their peers in physical, emotional, and/or social functioning (7). For example, a study in a cohort of 10 year old children born ≤ 28 weeks or with birth weight ≤ 1000 grams in Western Norway found a high rate of learning and inattention problems compared with matched term born controls (75% versus 20%) a problem that particularly affected boys (8). Additionally, parents of preterm and very low birth weight teenagers note significantly poorer performance in their child’s global health, behaviour, and physical functioning, whereas the teenagers themselves do not (7). These aspects affect participation in society and earning potential. Secondly, extremely low birth weight school-aged children also have lower health utility scores compared with their peers, and similar results were found for adolescents. Thus, childhood survivors of severe early onset FGR are less able to contribute to society and are more expensive users of healthcare.
Adult outcomes: Better physical outcomes as young adults will further reduce the risk of early onset of chronic respiratory symptoms in middle age, through a reduction in chronic lung disease of prematurity, and in cardiovascular performance, through improved blood vessel development and avoidance of childhood hypertension, outcomes that are currently found in survivors of early onset FGR. Furthermore adults who were severely growth restricted have a high risk of cardiovascular disease, diabetes and hypertension as described by the “Barker hypothesis” (9).

Put together this represents a significant long term impact on healthy ageing and participation in society, and economic potential for the individuals treated. Finally, alterations in the epigenome caused by a harmful fetal environment, affects the long term health of future generations (10). An intervention that improves the intrauterine environment for these individuals at the start of life, will thus impact throughout the rest of their lives, and into the next generation.

Impact on healthcare costs

Neonatal intensive care is a high-cost, high-technology, low-throughput discipline which operates under considerable pressure in most EU settings. Increasing gestation at delivery accompanied by a reduction in neonatal morbidity will reduce cost pressures on neonatal services. Costs of neonatal care and societal costs for health and education are heavily weighted by gestational age and the presence of severe neurosensory disability. In one recent estimation, the total economic cost to society of preterm birth in the UK alone was €3.6 Billion, with incremental costs per survivor ranging from €265k at 24 weeks to €120k at 27 weeks (11). Increasing the gestational age by 1 week is likely overall to result in approximately 30% reduction in costs over the preterm range. The cost of neonatal intensive care per case in babies less than 1000g has been estimated to average €45,397 (95th CI €35,030-€55,765). This is 50% higher than the cost for babies born weighing over 1000g, thus improvements in fetal growth result in immediate lower costs of care.

Looking more long term, some seriously disabled survivors have individual incremental annual costs of €36-60,000 in the 6th year (12), emphasising that a therapy that avoided major morbidity would likely reduce societal costs. For a child surviving up to 18 years, in 2009 the cost compared with a term survivor was estimated to be €27574 for a child born preterm (<37 weeks), €74,440 for a very preterm child (<33 weeks) and €114,152 for an extremely preterm child (<28 weeks) (11). This does not take into account the contribution of FGR, which would be present in all EVERREST treated children, rather than a percentage of the cohort as in this study.
Our aspiration for this therapy, should we find that it is safe and effective at improving fetal growth in severe early onset FGR is for it to become the standard of care in the EU within the next 15 to 20 years. This is based on previous experience with other innovative fetal therapies that have changed the face of obstetric care (13). Examples include fetal blood transfusion for anaemia caused by Rh alloimmunization, which was rolled out across the world within 20 years of the first procedure in the early 1980s (14) and is now the standard of care. More recently, laser coagulation of placental anastomoses for severe twin-to-twin transfusion syndrome was developed in the 1990s and fetoscopic laser is now available at specialist fetal medicine centres across the world (15). If EVERREST therapy moved into clinical practice we anticipate that each country in the EU would set up centres to safely deliver EVERREST therapy to women referred from local fetal medicine centres.

Secondary impacts
Pre-eclampsia is a multisystem disorder that is unique to human pregnancy and occurs in 5-10% of all pregnancies (16). Clinically, pre-eclampsia can manifest as either a maternal or a fetal syndrome although the combination of the two is common. The maternal syndrome consists of new hypertension diagnosed after 20 weeks of gestation, and proteinuria with or without multiorgan dysfunction including of the liver (elevated transaminases, abnormalities of clotting), kidneys (proteinuria, occasionally acute tubular necrosis), endothelium (hypertension, haemolysis, thrombocytopenia) and central nervous system (eclampsia and cerebrovascular accident). In the fetal syndrome there is fetal growth restriction, reduced amniotic fluid, and chronic hypoxaemia. In practice, pre-eclampsia can be considered as two conditions. The most severe form, found in 0.5% of all pregnancies, occurs early in gestation and requires preterm delivery for maternal and fetal indications before 34 week’s gestation (early-onset). The near-term form, although more common, is associated with lesser fetal and maternal morbidity (late-onset) (17).

Pre-eclampsia remains one of the leading causes of maternal death in the UK (18), Europe (19) and the US (20). Worldwide, pre-eclampsia and eclampsia are estimated to be responsible for approximately 14% of maternal deaths per year (50 000–75 000) (21). Whilst maternal deaths due to pre-eclampsia are rare, pre-eclampsia is a leading cause of substantial maternal morbidity. A UK study for example, reported that one-third of severe maternal morbidity was directly attributable to pre-eclampsia (22). A nationwide study in the US found that over one third of admissions for acute renal failure, and nearly one-fifth of admissions for coagulopathy, ventilation or cerebrovascular disorders occurred in women with severe pre-eclampsia or eclampsia (22). More recently, the long-term consequences for women diagnosed with pre-eclampsia have become clear, in particular chronic hypertension and an increase in lifetime cardiovascular risk (23). A recently estimated average cost for the hospital care of the mother and baby in a case of pre-eclampsia without eclampsia occurring, was equivalent to €12,110 (24). The costs are likely to be far higher in women with early-onset pre-eclampsia because of the additional neonatal care that accompanies preterm birth.

The early detection and management of pre-eclampsia remains a challenge and lags behind the significant advances made in other areas of perinatal care such as detailed fetal ultrasound and serum screening for Down’s syndrome (25). Low dose aspirin started by 16 weeks of gestation, approximately halves the risk of pre-eclampsia and is cost-effective (26) but is currently used only in women with risk factors for pre-eclampsia such as chronic hypertension or a previous history of pre-eclampsia. There is no effective treatment once the disorder manifests. Current management relies on controlling hypertension with a variety of anti-hypertensive medications, whilst monitoring the mother and fetus for signs of compromise in the hope that the fetus will continue to grow and that delivery can be delayed until after 34 weeks of gestation (27).

Pre-eclampsia is a heterogeneous disorder than involves abnormal placentation, endothelial dysfunction, and activation of inflammatory cascades. However, a key feature is an abnormal vascular response to placentation, that is associated with increased systemic vascular resistance, enhanced platelet aggregation, activation of the coagulation system, and endothelial cell dysfunction. Nitric oxide mediates many functions of the endothelium, including vasodilatation and inhibition of platelet aggregation. Early following the discovery of nitric oxide, it was hypothesized that reduced availability of nitric oxide may have a role in the pathogenesis of pre-eclampsia. More recently, women with pre-eclampsia have been found to have high circulating levels of an endogenous VEGF receptor sFlt1, that may decrease the bioavailability of VEGF, and therefore nitric oxide. Indeed, a pre-eclampsia-like syndrome can be induced in pregnant mice by intravascular injection of adenovirus containing the sFlt1 gene (sFlt1 mouse model of pre-eclampsia) (28). A possible therapeutic role for nitric oxide donors in the prevention or treatment of pre-eclampsia was therefore suggested. The latest Cochrane systematic review found six randomized controlled trials studying the effect of nitric oxide donors such as glyceryl trinitrate transdermal patches or L-arginine. Four trials included women at moderate to high risk of developing pre-eclampsia. There were insufficient data for reliable conclusions about the effects on pre-eclampsia, perinatal death, preterm birth or of having a small for gestational age baby, although nitric oxide donors had a trend towards being more effective than placebo or no intervention in preventing pre-eclampsia (29). The most common side effect was headache, due to the systemic vasodilatation that nitric oxide donors engenders.

A more local method of increasing the availability of VEGF and nitric oxide in the placenta would be the approach adopted in the EVERREST study. Localised delivery of VEGF directly to the placenta in a sustained fashion, over a period of weeks, is an attractive option where the pathology relates to placental ischaemia and reduced VEGF bioavailability. A recent study suggests that VEGF may be therapeutic in pre-eclampsia. Intravascular infusion of VEGF-121 attenuated the vascular dysfunction and diminished the fetal growth abnormality that is present in the sFlt1 mouse model of pre-eclampsia (30). Although the approach is more invasive than taking a tablet or using a patch, it is possible that if the local VEGF gene therapy is confirmed to be safe, that the risk benefit ratio would fall on the side of treatment, especially in those women who develop early-onset pre-eclampsia, and where the advantage to the fetus of remaining in utero, is far greater. Great care would need to be taken to evaluate the safety of the therapy on an individual patient basis since in pre-eclampsia, the mother’s health is also compromised. An estimate of the cost savings based on the neonate alone suggest that timely therapeutic delivery of EVERREST therapy could safely prolong the pregnancy by at least 4 more weeks (the length of time of maximal adenovirus expression) which would allow the fetus to achieve the threshold of 1000g before delivery and would reduce the costs of neonatal care by 50%. The maternal costs would be mitigated by the increased cost accrued through longer antenatal surveillance, but any reduction in the incidence of severe complications such as disseminated intravascular coagulopathy, renal and hepatic dysfunction for example, is likely to improve the economic evaluation of the therapy.

Less severe FGR
As described before, 25% of babies born very prematurely (before 32 weeks gestation) result from iatrogenic, indicated delivery for FGR. With approximately 1% of all births occurring before this gestation (54,000/year in the EU) this represents a large cohort of neonates that are at particularly high risk of mortality and long term morbidity. Over and above the background risk of prematurity related complications FGR babies are even more likely to have neurological complications, necrotizing enterocolitis, respiratory complications and retinopathy of prematurity (31). Current management of a fetus diagnosed with FGR secondary to placental dysfunction is carefully timed delivery (see section 1.2.1). The proposed study will address the most severely affected FGR fetuses in whom the risk of death and severe morbidity is highest i.e those with an estimated fetal weight of less than 600g where fetal growth has ceased. If EVERREST demonstrates an acceptable safety profile then this treatment could be tested in the far larger cohort of fetuses where delivery is planned for FGR at <32 weeks, but where the estimated fetal weight is more than 600g. The prospect for therapeutic benefit in this group is good because 1) the placental pathology is likely to be less severe than in the most seriously affected group, and will therefore be easier to reverse, 2) a risk in the severe FGR group is that a fetus that would have died in fact survives post EVERREST therapy, but is handicapped – this is less likely to happen in the less severe FGR group where VEGF gene therapy is more likely to result in morbidity-free survival. In fact, as long as the EVERREST treatment is safe it would be reasonable to assess efficacy in this group, even if efficacy were not proven in the most severe early onset FGR group. Although the economic impact of EVERREST will not be as great on a case by case basis in less severe FGR as in the most severely affected group, the overall savings of delaying delivery and increasing fetal birthweight in this group will be much larger owing to the larger number of treated pregnancies.

2. Main dissemination activities

A series of dissemination events took place during the duration of the project. The full list is included as an Annex in this report. During the project we aimed to target a wide variety of stakeholders and patients to ensure that findings of the project were disseminated. We also took part in any opportunity to present the project to the media. Fetal growth restriction is poorly understood outside fetal medicine as there is no treatment for the condition. Increasing understanding about the condition and it’s short and long-term consequences was therefore also one of our aims.

In total, 78 dissemination activities are included in this report. Some more details on these activities can be found in the following pages.

2.1 Type of activities

The three main activities used for dissemination in the EVERREST project were Oral presentations 58%, press releases 14% and posters in different types of events 12%.

2.2 Type of audience

Most of the dissemination events were addressed to the scientific community, but it is important to notice that nearly one third of the events were also address to the general public and to industry. This is important as we were able to advance the concept of fetal growth restriction as an obstetric disease that deserves investment.
Finally, it is important to mention that although the majority of the events had an international audience, there were some events with a regional character that allowed the consortium to disseminate the project to more geographical specific audience. There were 16 events with an important number of participants from Asia and Oceania, this is 20% of the total of the events. Also, in 4 events there were participants and audience from African countries, many of which are hard to target.

2.3 Dissemination event at International Fetal Growth Conference

One of the most important dissemination activities carried out during the EVERREST project was the participation in the Fetal Growth Conference 2018 in Milan, Italy.
This meeting provided an international, multidisciplinary forum for researchers and clinicians for presentations and in-depth discussions on fetal growth disorders and implications for best practice. The programme examined the latest evidence on growth standards and models, placental pathology, screening and surveillance, implementing antenatal growth assessment strategies, management of different clinical forms of fetal growth restriction, and pregnancy outcome. The consortium led a whole session on 3rd October 2018 (see below agenda) in which it was described the scientific rationale and results to date of the project. This was the only session in the conference to concentrate on treating fetal growth restriction and was very well received by delegates. The Consortium was invited to attend the next meeting in 2019 to give an update on the next stage.
The consortium also arranged to have a stand at the meeting in the foyer where information about the project, information about gene therapy in pregnancy and papers published from the consortium to date were distributed. Details of the attendees were collected to send them further information about the project.
The EVERREST session agenda during the Fetal Growth Conference 2018 has been included as attachment in the portal.

The EVERREST project was presented and discussed in a wide range of type of events that involved not only the scientific community but also the general public, industry and the policy makers sector. All the dissemination activities had a strong international character although there were some events that were addressed to a specific geographic sector.
• Exploitation and route to market

From week 54 of the project, TRIZELL took over responsibility for assessing information on the exploitation opportunities as well as updating market analysis in collaboration with UCL and other consortium partners, previously being led by MI partner and Dr Nigel Parker from TRIZELL took on the role of project Exploitation Manager.
After the promising results obtained in the project and provided that the results of the clinical studies support the market potential, TRIZELL will make efforts to ensure that the treatment for fetal growth restriction using the Ad.VEGF-DΔNΔC vector is further developed towards commercialisation. The Exploitation Manager will seek to establish early partnership with an external consortium company based on the results of the project, that might be interested in a co-development partnership post-project. Potential partners will evaluate the opportunity based on the risk and time to market as well as the ultimate market potential, so a key outcome of the EVERREST project was bringing the treatment past the toxicology and initial clinical stages that typically constitute very high risks of commercial failure for new therapeutics.
TRIZELL already has contacts with larger companies that are interested in commercialising gene therapies, but will also need to reach out to other companies that have focus within the therapeutic area. Typically such approaches are made mostly by direct contacts, supported by activity at partnering meetings and relevant scientific and commercial conferences. Importantly TRIZELL has in Finland one of few facilities in the world that would currently be capable of producing the Ad.VEGF-DΔNΔC vector for commercial supply. The facility has already obtained authorisation from the Finnish regulatory authority (FIMEA) for commercial manufacture of an adenoviral product, so TRIZELL has the knowledge of the requirements for such authorisation. TRIZELL also has developed a suspension culture-based process that can be used for scaled-up production of replication-defective adenoviruses. The manufacturing facility includes a suite with equipment to automatically fill up to 2000 vials per hour, demonstrating capacity for even the maximum anticipated market.

Reference List

(1) Thornton JG, Hornbuckle J, Vail A, Spiegelhalter DJ, Levene M. Infant wellbeing at 2 years of age in the Growth Restriction Intervention Trial (GRIT): multicentred randomised controlled trial. Lancet 2004 Aug 7;364(9433):513-20

(2) Draper ES, Manktelow BN, Field DJ, James D. Prediction of survival for preterm births by weight and gestational age: retrospective population based study. BMJ 1999;319:1093-7.
(3) Baschat AA, Cosmi E, Bilardo CM, Wolf H, Berg C, Rigano S, et al. Predictors of neonatal outcome in early-onset placental dysfunction. Obstetrics and Gynaecology 2007;109:253-61.
(4) Tyson JE, Parikh NA, Langer J, Green C, Higgins RD. Intensive Care for Extreme Prematurity: Moving Beyond Gestational Age. New England Journal of Medicine 2008;358:1672-81.
(5) Bose C, Van Marter LJ, Laughon M, O'Shea TM, Allred EN, Karna P, et al. Fetal growth restriction and chronic lung disease among infants born before the 28th week of gestation. Pediatrics 2009;(124):e450-e458.
(6) Damodaram M, Story L, Kulinskaya E, Rutherford M, Kumar S. Early adverse perinatal complications in preterm growth-restricted fetuses. Australian and New Zealand Journal of Obstetrics and Gynecology 2011;51:204-9.
(7) Zwicker JG, Harris SR. Quality of life of formerly preterm and very low birth weight infants from preschool age to adulthood: a systematic review. Pediatrics 2008 Feb;121(2):e366-e376.
(8) Vederhus BJ, Markestad T, Eide GE, Graue M, Halvorsen T. Health related quality of life after extremely preterm birth: a matched controlled cohort study. Health Qual Life Outcomes 2010;8:53.
(9) Barker DJ, Osmond C, Simmonds SJ, Wield GA. The relation of small head circumference and thinness at birth to death from cardiovascular disease in adult life. BMJ 1993;306:422-6.
(10) Torrens C, Poston L, Hanson MA. Transmission of raised blood pressure and endothelial dysfunction to the F2 generation induced by maternal protein restriction in the F0, in the absence of dietary challenge in the F1 generation. British Journal of Nutrition 2008;100:760-4.
(11) Mangham LJ, Petrou S, Doyle LW, Draper ES, Marlow N. The cost of preterm birth throughout childhood in England and Wales. Pediatrics 2009;123:e312-e327.
(12) Petrou S, Henderson J, Bracewell M, Hockley C, Wolke D, Marlow N. Pushing the boundaries of viability: the economic impact of extreme preterm birth. Early Hum Dev 2006 Feb;82(2):77-84.
(13) Rodeck CH. Early fetal therapy. Prenatal Diagnosis 2010;30:616-8.
(14) Rodeck CH, Kemp JR, Holman CA, Whitmore DN, Karnicki J, Austin MA. Direct intravascular fetal blood transfusion by fetoscopy in severe Rhesus isoimmunisation. Lancet 1981;8221:625-7.
(15) De Lia JE, Cruikshank DP, Keye WR, Jr. Fetoscopic neodymium:YAG laser occlusion of placental vessels in severe twin-twin transfusion syndrome. Obstet Gynecol 1990 Jun;75(6):1046-53.
(16) Sibhai B, Dekker G, Kupferminc M. Pre-eclampsia. Lancet 2005;365:785-99.
(17) Ness RB, Roberts JM. Heterogeneous causes constituting the single syndrome of preeclampsia: a hypothesis and its implications. Am J Obstet Gynecol 1996 Nov;175(5):1365-70.
(18) Lyons G. Saving mothers' lives: confidential enquiry into maternal and child health 2003-5. Int J Obstet Anesth 2008 Apr;17(2):103-5.
(19) Schutte JM, Steegers EA, Schuitemaker NW, Santema JG, de Boer K, Pel M, et al. Rise in maternal mortality in the Netherlands. BJOG 2010 Mar;117(4):399-406.
(20) Kuklina EV, Ayala C, Callaghan WM. Hypertensive disorders and severe obstetric morbidity in the United States. Obstet Gynecol 2009 Jun;113(6):1299-306.
(21) Bethesda MD. Global Burden of Disease for the Year 2001 by World Bank Region, for Use in Disease Control Priorities in Developing Countries, National Institutes of Heealth: WHO. Make every mother and child count. Geneva: World Health Organization; 2004.
(22) Waterstone M, Bewley S, Wolfe C. Incidence and predictors of severe obstetric morbidity: case-control study. BMJ 2001 May 5;322(7294):1089-93.
(23) Bellamy L, Casas JP, Hingorani AD, Williams DJ. Pre-eclampsia and risk of cardiovascular disease and cancer in later life: systematic review and meta-analysis. BMJ 2007 Nov 10;335(7627):974.
(24) Simon J, Gray A, Duley L. Cost-effectiveness of prophylactic magnesium sulphate for 9996 women with pre-eclampsia from 33 countries: economic evaluation of the Magpie Trial. BJOG 2006 Feb;113(2):144-51.
(25) Conde-Agudelo A, Villar J, Lindheimer M. World Health Organization systematic review of screening tests for preeclampsia. Obstetrics and Gynaecology 2004;104:1367-91.
(26) Bujold E, Roberge S, Lacasse Y, Bureau M, Audibert F, Marcoux S, et al. Prevention of preeclampsia and intrauterine growth restriction with aspirin started in early pregnancy: a meta-analysis. Obstet Gynecol 2010 Aug;116(2 Pt 1):402-14.
(27) National Collaborating Centre for Women's and Children's Health. Hypertension in pregnancy: the management of hypertensive disorders of pregnancy. Royal College of Obstetricians and Gynaecologists; 2010.
(28) Lu F, Mongo M, Tamayo E, Maner W, Al-Hendy A, Anderson GD, et al. The effect of over-expression of sFlt-1 on blood pressure and the occurrence of other manifestations of preeclampsia in unrestrained conscious pregnant mice. American Journal of Obstetrics and Gynecology 2007;196:396.
(29) Meher S, Duley L. Nitric oxide for preventing pre-eclampsia and its complications. Cochrane Database Syst Rev 2007;(2):CD006490.
(30) Mateus J, Bytautiene E, Lu F, Tamayo EH, Betancourt A, Hankins GD, et al. Endothelial growth factor therapy improves preeclampsia-like manifestations in a murine model induced by overexpression of sVEGFR-1. Am J Physiol Heart Circ Physiol 2011 Nov;301(5):H1781-H1787.
(31) Sibai B, Dekker G, Kupferminc M. Pre-eclampsia. Lancet 2005 Feb 26;365(9461):785-99.

List of Websites:

Coordinator: Anna David PhD
Professor and Consultant in Obstetrics and Maternal Fetal Medicine.
Director of the Institute for Women’s Health.
Honorary Professor of Fetal Medicine, KU Leuven.

EGA Institute for Women's Health | Faculty of Population Health Sciences | University College London
Room 244, 2nd floor, Medical School Building, 74 Huntley Street, London WC1E 6AU