Medical management and surgery versus medical management alone for symptomatic cerebral cavernous malformation (CARE): a feasibility study and randomised, open, pragmatic, pilot phase trial

BACKGROUND

The highest priority uncertainty for people with symptomatic cerebral cavernous malformation is whether to have medical management and surgery or medical management alone. We conducted a pilot phase randomised controlled trial to assess the feasibility of addressing this uncertainty in a definitive trial.

METHODS

The CARE pilot trial was a prospective, randomised, open-label, assessor-blinded, parallel-group trial at neuroscience centres in the UK and Ireland. We aimed to recruit 60 people of any age, sex, and ethnicity who had mental capacity, were resident in the UK or Ireland, and had a symptomatic cerebral cavernous malformation. Computerised, web-based randomisation assigned participants (1:1) to medical management and surgery (neurosurgical resection or stereotactic radiosurgery) or medical management alone, stratified by the neurosurgeon's and participant's consensus about the intended type of surgery before randomisation. Assignment was open to investigators, participants, and carers, but not clinical outcome event adjudicators. Feasibility outcomes included site engagement, recruitment, choice of surgical management, retention, adherence, data quality, clinical outcome event rate, and protocol implementation. The primary clinical outcome was symptomatic intracranial haemorrhage or new persistent or progressive non-haemorrhagic focal neurological deficit due to cerebral cavernous malformation or surgery during at least 6 months of follow-up. We analysed data from all randomly assigned participants according to assigned management. This trial is registered with ISRCTN (ISRCTN41647111) and has been completed.

FINDINGS

Between Sept 27, 2021, and April 28, 2023, 28 (70%) of 40 sites took part, at which investigators screened 511 patients, of whom 322 (63%) were eligible, 202 were approached for recruitment, and 96 had collective uncertainty with their neurosurgeon about whether to have surgery for a symptomatic cerebral cavernous malformation. 72 (22%) of 322 eligible patients were randomly assigned (mean recruitment rate 0·2 [SD 0·25] participants per site per month) at a median of 287 (IQR 67-591) days since the most recent symptomatic presentation. Participants' median age was 50·6 (IQR 38·6-59·2) years, 68 (94%) of 72 participants were adults, 41 (57%) were female, 66 (92%) were White, 56 (78%) had a previous intracranial haemorrhage, and 28 (39%) had a previous epileptic seizure. The intended type of surgery before randomisation was neurosurgical resection for 19 (26%) of 72, stereotactic radiosurgery for 44 (61%), and no preference for nine (13%). Baseline clinical and imaging data were complete for all participants. 36 participants were randomly assigned to medical management and surgery (12 to neurosurgical resection and 24 to stereotactic radiosurgery) and 36 to medical management alone. Three (4%) of 72 participants withdrew, one was lost to follow-up, and one declined face-to-face follow-up, leaving 67 (93%) retained at 6-months' clinical follow-up. 61 (91%) of 67 participants with follow-up adhered to the assigned management strategy. The primary clinical outcome occurred in two (6%) of 33 participants randomly assigned to medical management and surgery (8·0%, 95% CI 2·0-32·1 per year) and in two (6%) of 34 participants randomly assigned to medical management alone (7·5%, 1·9-30·1 per year). Investigators reported no deaths, no serious adverse events, one protocol violation, and 61 protocol deviations.

INTERPRETATION

This pilot phase trial exceeded its recruitment target, but a definitive trial will require extensive international engagement.

FUNDING

National Institute for Health and Care Research.

Feasibility of comparing medical management and surgery (with neurosurgery or stereotactic radiosurgery) with medical management alone in people with symptomatic brain cavernoma - protocol for the Cavernomas: A Randomised Effectiveness (CARE) pilot trial

INTRODUCTION

The top research priority for cavernoma, identified by a James Lind Alliance Priority setting partnership was 'Does treatment (with neurosurgery or stereotactic radiosurgery) or no treatment improve outcome for people diagnosed with a cavernoma?' This pilot randomised controlled trial (RCT) aims to determine the feasibility of answering this question in a main phase RCT.

METHODS AND ANALYSIS

We will perform a pilot phase, parallel group, pragmatic RCT involving approximately 60 children or adults with mental capacity, resident in the UK or Ireland, with an unresected symptomatic brain cavernoma. Participants will be randomised by web-based randomisation 1:1 to treatment with medical management and with surgery (neurosurgery or stereotactic radiosurgery) versus medical management alone, stratified by prerandomisation preference for type of surgery. In addition to 13 feasibility outcomes, the primary clinical outcome is symptomatic intracranial haemorrhage or new persistent/progressive focal neurological deficit measured at 6 monthly intervals. An integrated QuinteT Recruitment Intervention (QRI) evaluates screening logs, audio recordings of recruitment discussions, and interviews with recruiters and patients/parents/carers to identify and address barriers to participation. A Patient Advisory Group has codesigned the study and will oversee its progress.

ETHICS AND DISSEMINATION

This study was approved by the Yorkshire and The Humber-Leeds East Research Ethics Committee (21/YH/0046). We will submit manuscripts to peer-reviewed journals, describing the findings of the QRI and the Cavernomas: A Randomised Evaluation (CARE) pilot trial. We will present at national specialty meetings. We will disseminate a plain English summary of the findings of the CARE pilot trial to participants and public audiences with input from, and acknowledgement of, the Patient Advisory Group.

TRIAL REGISTRATION NUMBER

ISRCTN41647111.

Essential role for thymosin β4 in regulating vascular smooth muscle cell development and vessel wall stability

RATIONALE

Compromised development of blood vessel walls leads to vascular instability that may predispose to aneurysm with risk of rupture and lethal hemorrhage. There is currently a lack of insight into developmental insults that may define the molecular and cellular characteristics of initiating and perpetrating factors in adult aneurismal disease.

OBJECTIVE

To investigate a role for the actin-binding protein thymosin β4 (Tβ4), previously shown to be proangiogenic, in mural cell development and vascular wall stability.

METHODS AND RESULTS

Phenotypic analyses of both global and endothelial-specific loss-of-function Tβ4 mouse models revealed a proportion of Tβ4-null embryos with vascular hemorrhage coincident with a reduction in smooth muscle cell coverage of their developing vessels. Mechanistic studies revealed that extracellular Tβ4 can stimulate differentiation of mesodermal progenitor cells to a mature mural cell phenotype through activation of the transforming growth factor-beta (TGFβ) pathway and that reduced TGFβ signaling correlates with the severity of hemorrhagic phenotype in Tβ4-null vasculature.

CONCLUSIONS

Tβ4 is a novel endothelial secreted trophic factor that functions synergistically with TGFβ to regulate mural cell development and vascular wall stability. These findings have important implications for understanding congenital anomalies that may be causative for adult-onset vascular instability.

Thymosin beta4 facilitates epicardial neovascularization of the injured adult heart

Ischemic heart disease complicated by coronary artery occlusion causes myocardial infarction (MI), which is the major cause of morbidity and mortality in humans (http://www.who.int/cardiovascular_diseases/resources/atlas/en/index.html). After MI the human heart has an impaired capacity to regenerate and, despite the high prevalence of cardiovascular disease worldwide, there is currently only limited insight into how to stimulate repair of the injured adult heart from its component parts. Efficient cardiac regeneration requires the replacement of lost cardiomyocytes, formation of new coronary blood vessels, and appropriate modulation of inflammation to prevent maladaptive remodeling, fibrosis/scarring, and consequent cardiac dysfunction. Here we show that thymosin beta4 (Tbeta4) promotes new vasculature in both the intact and injured mammalian heart. We demonstrate that limited EPDC-derived endothelial-restricted neovascularization constitutes suboptimal "endogenous repair," following injury, which is significantly augmented by Tbeta4 to increase and stabilize the vascular plexus via collateral vessel growth. As such, we identify Tbeta4 as a facilitator of cardiac neovascularization and highlight adult EPDCs as resident progenitors which, when instructed by Tbeta4, have the capacity to sustain the myocardium after ischemic damage.

Thymosin β4 and Ac-SDKP: Tools to mend a broken heart

Thymosin beta4 - an endogenously occurring 43 amino acid peptide - has recently been shown to possess cardioprotective properties in the setting of acute myocardial infarction. This review focuses on the reported mechanisms of action through which Thymosin beta4 might accomplish this effect and the clinical prospects for its use as a therapeutic agent.

Thymosin beta4 and angiogenesis: modes of action and therapeutic potential

Here we review the mechanisms by which Thymosin beta4 (Tbeta4) regulates angiogenesis, its role in processes, such as wound healing and tumour progression and we discuss in more detail the role of Tbeta4 in the cardiovascular system and significant recent findings implicating Tbeta4 as a potential therapeutic agent for ischaemic heart disease.