Efficacy and safety of intravenous bevacizumab on severe bleeding associated with hemorrhagic hereditary telangiectasia: A national, randomized multicenter trial

BEST study: one-year descriptive follow-up of bevacizumab treatment in hereditary haemorrhagic telangiectasia post-BABH interventional study

Background

Hereditary haemorrhagic telangiectasia (HHT) is a genetic vascular disorder characterised by telangiectases, which cause nasal and gastrointestinal (GI) bleeding, and visceral arteriovenous malformations. Since 2012 bevacizumab, a monoclonal antibody targeting vascular endothelial growth factor, has been a promising treatment for HHT-related bleeding and was evaluated in the phase II BABH study.

Objective

To follow and describe evolution and treatments of patients with HHT post-BABH study.

Design

This study is a 1-year, multi-centre descriptive study.

Methods

We collected clinical (nose and GI bleeding, red blood cell transfusions) and biological (haemoglobin and ferritin levels) data and treatment information.

Results

Of 22 patients included across 4 centers, 15 received bevacizumab. Among them, 12 (86%) had a >50% decrease in the number of RBC units transfused 3 months post-treatment. Mean haemoglobin levels increased from 83.08 to 105.98 g/L.

Conclusion

Bevacizumab effectively reduces RBC transfusions and is efficient for treating severe bleeding in patients with HHT.

Trial registration

This trial was registered with the ClinicalTrials.gov Identifier #NCT06039124.

The Effect of Systemic Bevacizumab on Epistaxis-Related Outcomes in Hereditary Hemorrhagic Telangiectasia: A Systematic Review and Meta-Analysis

BACKGROUND

The evidence-based recommendation for the use of systemic bevacizumab to treat refractory epistaxis in hereditary hemorrhagic telangiectasia (HHT) is based on limited and historical data. An updated synthesis of the available literature is warranted.

METHODS

A systematic review and meta-analysis were conducted using PRISMA guidelines to evaluate the use of systemic bevacizumab for HHT-related epistaxis. A search was conducted using three databases up to September 2024 for studies assessing the effect of systemic bevacizumab use on epistaxis outcomes in HHT. Outcome measures included epistaxis severity score (ESS), hemoglobin, red blood cell (RBC), and iron transfusion requirements and adverse effects. Random effects meta-analysis was performed for change in ESS (ΔESS) and change in hemoglobin (ΔHb). Literature quality was assessed using the Joanne Briggs Institute critical appraisal tools.

RESULTS

A total of 10 studies with 225 total patients were included. Systemic bevacizumab was associated with a significant posttreatment reduction in mean ESS of -3.33 (95% CI -3.62 to -3.03) and a significant increase in mean Hb of 2.38 g/dL (95% CI 1.45-3.30) compared to pretreatment. All cohort studies found a significant reduction in RBC and iron transfusions following systemic bevacizumab treatment. The most frequently reported adverse effect of systemic bevacizumab was hypertension.

CONCLUSION

Systemic bevacizumab is associated with significant improvements in epistaxis severity, hemoglobin, and transfusion requirements in HHT-related epistaxis. Adequately powered studies are required to strengthen this finding. Patient selection criteria, standardized maintenance dosing, and long-term treatment data require further study.

Efficacy of bevacizumab in hereditary hemorrhagic telangiectasia: a systematic review and network meta-analysis

BACKGROUND

Hereditary Hemorrhagic Telangiectasia (HHT) is an autosomal multi-systemic vascular dysplasia caused by gene mutations that lead to recurrent epistaxis and other serious complications including mucocutaneous telangiectasias, gastrointestinal bleeding, and arteriovenous malformations. Treatment is limited to symptomatic relief with no approved standard therapy. Bevacizumab is a monoclonal antibody used primarily in treating metastatic malignancies and ophthalmology. Several studies have shown that bevacizumab is effective in the treatment of HHT-related epistaxis with a high safety profile.

PURPOSE

This systematic review and network meta-analysis aims to explore the efficacy and safety of bevacizumab in the treatment of HHT epistaxis.

METHODS

A comprehensive literature search was done in many databases, including PubMed, Web of Science, Scopus, and the Cochrane Library. We conducted our network meta-analysis using R version 4.2.2 and R Studio version 2022.07.2. Dichotomous data was analyzed as risk ratio and 95% confidence interval and continuous data as mean difference and 95% confidence interval.

RESULTS

We included four randomized clinical trials in our network meta-analysis. Different doses of bevacizumab failed to yield any statistically significant difference in reducing the epistaxis severity score, the number of epistaxis episodes, the duration of epistaxis, or improving hemoglobin levels compared to placebo or other comparators. The pooled effect sizes for all outcomes were homogenous.

CONCLUSION

Bevacizumab failed to show any significant difference compared to tranexamic acid, estriol, or placebo. These findings underscore the challenges in addressing HHT-related symptoms and highlight the ongoing need for innovative and more effective interventions.

Hereditary Hemorrhagic Telangiectasia: On the Brink of a New Treatment Era?

Hereditary hemorrhagic telangiectasia (HHT) is an inherited vascular disorder with highly variable penetrance, affecting up to 1 in 5,000 individuals. It is characterized by the presence of abnormal blood vessels that can lead to excessive bleeding-most frequently recurrent nosebleeds (epistaxis), skin and mucosal telangiectasias (small, dilated blood vessels), as well as arteriovenous malformations (AVMs) that can form in various organs, particularly the lungs, liver, and brain. HHT is caused by loss-of-function mutations in the BMP9-10/ENG/ALK1/SMAD4 signaling pathway, an important mediator of vascular quiescence. HHT possesses significant challenges for affected individuals, as the complications can range from mild to life-threatening events, depending on the severity and location of the vascular abnormalities. Despite this bleeding disorder being not uncommon, nowadays no specific treatment is as yet available for HHT and most current therapies include repurposed drugs. The aim of this review was to show therapeutic advances on the basis of recent promising clinical trials for HHT.

Hereditary haemorrhagic telangiectasia

Hereditary haemorrhagic telangiectasia (HHT) is a vascular dysplasia inherited as an autosomal dominant trait and caused by loss-of-function pathogenic variants in genes encoding proteins of the BMP signalling pathway. Up to 90% of disease-causal variants are observed in ENG and ACVRL1, with SMAD4 and GDF2 less frequently responsible for HHT. In adults, the most frequent HHT manifestations relate to iron deficiency and anaemia owing to recurrent epistaxis (nosebleeds) or bleeding from gastrointestinal telangiectases. Arteriovenous malformations (AVMs) in the lungs, liver and the central nervous system cause additional major complications and often complex symptoms, primarily due to vascular shunting, which is right-to-left through pulmonary AVMs (causing ischaemic stroke or cerebral abscess) and left-to-right through systemic AVMs (causing high cardiac output). Children usually experience isolated epistaxis; in rare cases, childhood complications occur from large AVMs in the lungs or central nervous system. Management goals encompass control of epistaxis and intestinal bleeding from telangiectases, screening for and treatment of iron deficiency (with or without anaemia) and AVMs, genetic counselling and evaluation of at-risk family members. Novel therapeutics, such as systemic antiangiogenic therapies, are actively being investigated. Although HHT is associated with increased morbidity, the appropriate screening and treatment of visceral AVMs, and the effective management of bleeding and anaemia, improves quality of life and overall survival.

Effect of oral nintedanib vs placebo on epistaxis in hereditary hemorrhagic telangiectasia: the EPICURE multicenter randomized double-blind trial

Epistaxis greatly affects patients with hereditary hemorrhagic telangiectasia (HHT). Although few systemic treatment exist, nintedanib, is a good candidate thanks to its anti-angiogenic activity. Our main objective was to evaluate the efficacy of oral nintedanib on epistaxis duration in HHT patients with moderate to severe epistaxis. This multicenter phase 2 randomized, placebo-controlled, double-blind trial was conducted between June 2020 and February 2023. Inclusion criteria were being over 18 years old and having a confirmed HHT diagnosis with an epistaxis severity score greater than 4. Sixty patients were randomized to receive either nintedanib or placebo for 12 weeks with a 12 week follow-up. The primary endpoint was the proportion of patients achieving a reduction of at least 50% in mean monthly epistaxis duration comparing the 8 weeks before treatment to the last 8 weeks of treatment. Main secondary outcomes included monthly duration and frequency of epistaxis and hemoglobin levels. Of the 60 randomized patients, 56 completed the trial. Thirteen patients (43%) in the nintedanib group vs 8 (27%) in the placebo group met the primary endpoint (p = 0.28). We observed a significant decrease in median epistaxis (57% vs 27%, p = 0.013) and a significant increase in median hemoglobin levels (+ 18 vs - 1 g/L, p = 0.02) in the nintedanib vs the placebo group. Although we did not achieve our primary outcome, we observed a significant reduction in epistaxis duration and a significant increase in hemoglobin levels in patients treated with nintedanib. This supports the efficacy of nintedanib, and further studies are needed.

Potential and emerging therapeutics for HHT

A 64-year-old woman with hereditary hemorrhagic telangiectasia (HHT) characterized by a pathological variant in ACVRL1 presents to the clinic for follow-up. Manifestations of HHT include frequent epistaxis and gastrointestinal bleeding, leading to iron-deficiency anemia. Bevacizumab is initiated, with resolution of the anemia. While maintained on a regimen of bevacizumab every 6 weeks, she continues to report frequent epistaxis and has ongoing iron-deficiency requiring periodic iron infusions. She also finds the bevacizumab infusions inconvenient. She is interested in discussing other options for managing her disease.

Recent advances in the treatment of refractory gastrointestinal angiodysplasia

Gastrointestinal angiodysplasia (GIA) is a common, acquired, vascular abnormality of the digestive tract, and a frequent cause of bleeding. Refractory GIA criteria usually include recurrent bleeding, transfusions and/or repeat endoscopy. Pharmacological and interventional treatments have been the subject of recent high-quality publications. This review provides an overview of the latest updates on non-endoscopic management of refractory GIA. Aortic valve replacement has shown its efficacy in Heyde syndrome and should be considered if indicated. Anti-angiogenic drugs, such as Octreotide and Thalidomide, are efficient treatments of refractory GIA-related bleeding. Somatostatin analogs should, based on efficacy and tolerance profile, be considered first. In the future, a better understanding of the physiopathology of GIA might help develop new-targeted therapies.

Pomalidomide for Epistaxis in Hereditary Hemorrhagic Telangiectasia

BACKGROUND

Hereditary hemorrhagic telangiectasia (HHT) is characterized by extensive telangiectasias and arteriovenous malformations. The primary clinical manifestation is epistaxis that results in iron-deficiency anemia and reduced health-related quality of life.

METHODS

We conducted a randomized, placebo-controlled trial to evaluate the safety and efficacy of pomalidomide for the treatment of HHT. We randomly assigned patients, in a 2:1 ratio, to receive pomalidomide at a dose of 4 mg daily or matching placebo for 24 weeks. The primary outcome was the change from baseline through week 24 in the Epistaxis Severity Score (a validated bleeding score in HHT; range, 0 to 10, with higher scores indicating worse bleeding). A reduction of 0.71 points or more is considered clinically significant. A key secondary outcome was the HHT-specific quality-of-life score (range, 0 to 16, with higher scores indicating more limitations).

RESULTS

The trial was closed to enrollment in June 2023 after a planned interim analysis met a prespecified threshold for efficacy. A total of 144 patients underwent randomization; 95 patients were assigned to receive pomalidomide and 49 to receive placebo. The baseline mean (±SD) Epistaxis Severity Score was 5.0±1.5, a finding consistent with moderate-to-severe epistaxis. At 24 weeks, the mean difference between the pomalidomide group and the placebo group in the change from baseline in the Epistaxis Severity Score was -0.94 points (95% confidence interval [CI], -1.57 to -0.31; P = 0.004). The mean difference in the changes in the HHT-specific quality-of-life score between the groups was -1.4 points (95% CI, -2.6 to -0.3). Adverse events that were more common in the pomalidomide group than in the placebo group included neutropenia, constipation, and rash.

CONCLUSIONS

Among patients with HHT, pomalidomide treatment resulted in a significant, clinically relevant reduction in epistaxis severity. No unexpected safety signals were identified. (Funded by the National Heart, Lung, and Blood Institute; PATH-HHT Clinicaltrials.gov number, NCT03910244).

Hereditary Hemorrhagic Telangiectasia (Osler's Disease): Systemic, Interdisciplinary, Relatively Common—and Often Missed

BACKGROUND

Hereditary hemorrhagic telangiectasia (HHT, Rendu- Osler-Weber disease, or Osler's disease for short) is a systemic disease that can severely impair the quality of life and that requires interdisciplinary treatment. Among rare diseases, it is relatively common, with a prevalence of approximately 1/5000.

METHODS

This review is based on publications retrieved by a selective literature search, including the two international guidelines on clinically relevant aspects of HHT.

RESULTS

On average, about two decades elapse between the initial symptoms and the diagnosis of HHT. 95% of patients have nosebleeds; these usually begin before age 20 but can occur at any time, from infancy to old age. The diagnosis is usually made on clinical grounds on the basis of the characteristic telangiectases, a positive family history, and possible involvement of the gastrointestinal tract, lungs, liver, and brain. Nosebleeds can sometimes be reduced by outpatient measures including counseling on keeping the nose moist (expert consensus), self-application of a nasal packing (which improves the quality of life, according to an online survey), and the prescription of tranexamic acid (reduction of nosebleeds from 17.3% [5.5; 27.6] to 54%). In particular, screening (expert consensus) for pulmonary vascular malformations (frequency 10-50%) can prevent many adverse outcomes. If pulmonary vascular malformations cannot be ruled out, antibiotic prophylaxis is recommended before medical procedures that can cause bacteremia (expert consensus).

CONCLUSION

Broad awareness of the condition, early diagnosis, and interdisciplinary treatment improve the quality of life and ultimate outcome of persons with HHT. Nevertheless, there are few options supported by good evidence for the appropriate treatment of this rare, often serious disease..

How I treat bleeding in hereditary hemorrhagic telangiectasia

ABSTRACT

Hereditary hemorrhagic telangiectasia (HHT; Osler-Weber-Rendu disease) affects 1 in 5000 persons, making it the second most common inherited bleeding disorder worldwide. Telangiectatic bleeding, primarily causing recurrent epistaxis and chronic gastrointestinal bleeding, is the most common and most important manifestation of this multisystem vascular disorder. HHT-associated bleeding results in substantial psychosocial morbidity and iron deficiency anemia that may be severe. Although there remain no regulatory agency-approved therapies for HHT, multiple large studies, including randomized controlled trials, have demonstrated the safety and efficacy of antifibrinolytics for mild-to-moderate bleeding manifestations and systemic antiangiogenic drugs including pomalidomide and bevacizumab for moderate-to-severe bleeding. This has led to a recent paradigm shift away from repetitive temporizing procedural management toward effective systemic medical therapeutics to treat bleeding in HHT. In this article, 4 patient cases are used to illustrate the most common and most challenging presentations of HHT-associated bleeding that hematologists are likely to encounter in daily practice. Built on a framework of published data and supported by extensive clinical experience, guidance is given for modern evidence-based approaches to antifibrinolytic therapy, antiangiogenic therapy, and iron deficiency anemia management across the HHT disease severity spectrum.

Pathophysiology in Brain Arteriovenous Malformations: Focus on Endothelial Dysfunctions and Endothelial-to-Mesenchymal Transition

Brain arteriovenous malformations (bAVMs) substantially increase the risk for intracerebral hemorrhage (ICH), which is associated with significant morbidity and mortality. However, the treatment options for bAVMs are severely limited, primarily relying on invasive methods that carry their own risks for intraoperative hemorrhage or even death. Currently, there are no pharmaceutical agents shown to treat this condition, primarily due to a poor understanding of bAVM pathophysiology. For the last decade, bAVM research has made significant advances, including the identification of novel genetic mutations and relevant signaling in bAVM development. However, bAVM pathophysiology is still largely unclear. Further investigation is required to understand the detailed cellular and molecular mechanisms involved, which will enable the development of safer and more effective treatment options. Endothelial cells (ECs), the cells that line the vascular lumen, are integral to the pathogenesis of bAVMs. Understanding the fundamental role of ECs in pathological conditions is crucial to unraveling bAVM pathophysiology. This review focuses on the current knowledge of bAVM-relevant signaling pathways and dysfunctions in ECs, particularly the endothelial-to-mesenchymal transition (EndMT).

Hereditary hemorrhagic telangiectasia: from signaling insights to therapeutic advances

Hereditary hemorrhagic telangiectsia (HHT) is an inherited vascular disorder with highly variable expressivity, affecting up to 1 in 5,000 individuals. This disease is characterized by small arteriovenous malformations (AVMs) in mucocutaneous areas (telangiectases) and larger visceral AVMs in the lungs, liver, and brain. HHT is caused by loss-of-function mutations in the BMP9-10/ENG/ALK1/SMAD4 signaling pathway. This Review presents up-to-date insights on this mutated signaling pathway and its crosstalk with proangiogenic pathways, in particular the VEGF pathway, that has allowed the repurposing of new drugs for HHT treatment. However, despite the substantial benefits of these new treatments in terms of alleviating symptom severity, this not-so-uncommon bleeding disorder still currently lacks any FDA- or European Medicines Agency-approved (EMA-approved) therapies.

Exploring the Spectrum of VEGF Inhibitors' Toxicities from Systemic to Intra-Vitreal Usage in Medical Practice

The use of Vascular Endothelial Growth Factor inhibitors (VEGFi) has become prevalent in the field of medicine, given the high incidence of various pathological conditions necessitating VEGF inhibition within the general population. These conditions encompass a range of advanced neoplasms, such as colorectal cancer, non-small cell lung cancer, renal cancer, ovarian cancer, and others, along with ocular diseases. The utilization of VEGFi is not without potential risks and adverse effects, requiring healthcare providers to be well-prepared for identification and management. VEGFi can be broadly categorized into two groups: antibodies or chimeric proteins that specifically target VEGF (bevacizumab, ramucirumab, aflibercept, ranibizumab, and brolucizumab) and non-selective and selective small molecules (sunitinib, sorafenib, cabozantinib, lenvatinib, regorafenib, etc.) designed to impede intracellular signaling of the VEGF receptor (RTKi, receptor tyrosine kinase inhibitors). The presentation and mechanisms of adverse effects resulting from VEGFi depend primarily on this distinction and the route of drug administration (systemic or intra-vitreal). This review provides a thorough examination of the causes, recognition, management, and preventive strategies for VEGFi toxicities with the goal of offering support to oncologists in both clinical practice and the design of clinical trials.

Meta-analysis of efficacy and safety of bevacizumab in the treatment of hereditary hemorrhagic telangiectasia epistaxis

Objective: A meta-analysis is conducted to evaluate the effectiveness and safety of bevacizumab in hereditary hemorrhagic telangiectasia (HHT) epistaxis. Method: Two researchers search PubMed, EMBASE and Web of Science databases from their inception until September 3th, 2023. The literature is read and screened, and valid data extracted, collated and analyzed. Its quality is then assessed using the Cochrane risk assessment scale. This study uses Endnote 9.3 software for literature management and RevMan 5.3.1 software for evaluation. Results: A total of 7 documents met the requirements, including a total of 359 patients, and the literature quality evaluation was grade B. The Meta-analysis results showed that:Bevacizumab reduces the Epistaxis Severity Score (ESS) in patients with HHT epistaxis compared with the control [WMD = -0.22,95%CI (-0.38, -0.05), p = 0.01]. However, there is no significant effect on duration of epistaxis [WMD = -15.59, 95%CI (-70.41,39.23), p = 0.58] and number of epistaxes [WMD = -1.27,95%CI (-10.23,7.70), p = 0.78] in patients with HHT epistaxis. In terms of adverse effects, there is no significant difference between the bevacizumab group and control group [OR = 1.36, 95% CI (0.54, 3.44), p = 0.52]. Conclusion: Bevacizumab is superior to the control group in the treatment of HHT epistaxis, and adverse reactions are not further increased in the bevacizumab group than in the control group, suggesting that bevacizumab has clinical value in the treatment of HHT epistaxis.