An old drug for a rare disease: The example of celiprolol for vascular Ehlers-Danlos syndrome

Current Evidence and Future Perspectives in the Medical Management of Vascular Ehlers-Danlos Syndrome: Focus on Vascular Prevention

Vascular Ehlers-Danlos syndrome (vEDS) is a rare autosomal dominant connective tissue disease resulting from pathogenic variants in the collagen type III alpha 1 chain (COL3A1) gene, encoding type III procollagen. Patients with vEDS present with severe tissue fragility that can result in arterial aneurysm, dissection, or rupture, especially of medium-caliber vessels. Although early reports have indicated a very high mortality rate in affected patients, with an estimated median survival of around 50 years, recent times have seen a remarkable improvement in outcomes in this population. This shift could be related to greater awareness of the disease among patients and physicians, with improved management both in terms of follow-up and treatment of complications. Increasing use of drugs acting on the cardiovascular system may also have contributed to this improvement. In particular, celiprolol, a β1 cardio-selective blocker with a β2-agonist vasodilator effect, has been shown to reduce rates of vascular events in patients with vEDS. However, the evidence on the true benefits and possible mechanisms responsible for the protective effect of celiprolol in this specific setting remains limited. Drugs targeting the extracellular matrix organization and autophagy-lysosome pathways are currently under investigation and could play a role in the future. This narrative review aims to summarize current evidence and future perspectives on vEDS medical treatment, with a specific focus on vascular prevention.

Drug repurposing: From the discovery of a useful pharmacological effect to making the treatment available to the patient

The repurposing of a medicine already on the market to a new indication could be an opportunity to respond rapidly to a therapeutic need not yet covered, particularly in the context of rare and neglected diseases, or health emergencies. However, at each stage, difficulties may arise that will prevent the repurposed drug from being provided to patients. Beyond fortuity or a systematic strategy to detect a useful pharmacological effect, the implementation of the preclinical and clinical stages is sometimes complicated by the difficulty of accessing the molecule and its pharmaceutical data. Furthermore, relevant clinical results will not always be sufficient to ensure that a marketing authorisation is obtained or that patients receive satisfactory care. In addition to describing these various obstacles, the round table provided an opportunity to put forward recommendations for overcoming them, in particular the creation of a public-private partnership structure with sufficient funding to be able to offer individualised support for projects up to and including the marketing application.

Comparative therapeutic strategies for preventing aortic rupture in a mouse model of vascular Ehlers-Danlos syndrome

Vascular Ehlers-Danlos syndrome is a rare inherited disorder caused by genetic variants in type III collagen. Its prognosis is especially hampered by unpredictable arterial ruptures and there is no therapeutic consensus. We created a knock-in Col3a1^+/G182R mouse model and performed a complete genetic, molecular and biochemical characterization. Several therapeutic strategies were also tested. Col3a1^+/G182R mice showed a spontaneous mortality caused by thoracic aortic rupture that recapitulates the vascular Ehlers-Danlos syndrome with a lower survival rate in males, thin non-inflammatory arteries and an altered arterial collagen. Transcriptomic analysis of aortas showed upregulation of genes related to inflammation and cell stress response. Compared to water, survival rate of Col3a1^+/G182R mice was not affected by beta-blockers (propranolol or celiprolol). Two other vasodilating anti-hypertensive agents (hydralazine, amlodipine) gave opposite results on aortic rupture and mortality rate. There was a spectacular beneficial effect of losartan, reversed by the cessation of its administration, and a marked deleterious effect of exogenous angiotensin II. These results suggest that blockade of the renin angiotensin system should be tested as a first-line medical therapy in patients with vascular Ehlers-Danlos syndrome.

Vascular Ehlers-Danlos syndrome (vEDS) is a rare vascular genetic disease leading to life-threatening arterial and colonic fragility in young adulthood. We created a new mutant mouse with a typical disease-causing variant in the gene responsible for vEDS. This mouse recapitulates the vEDS vascular features with spontaneous mortality due to aortic rupture. We also tested several antihypertensive therapeutic strategies to improve the survival of this mouse. Only one of the 5 tested medications, losartan, which blocks the activity of angiotensin II, a vasoconstricting hormone, improves the survival of this mouse. Moreover, the deleterious effect of angiotensin II administration further highlights the role of angiotensin II on susceptibility to aortic rupture in this mouse. These results support the interest of a therapeutic trial in vEDS patients using angiotensin II receptor blockers.