Targeting COL4A1-Related Small Vessel Disease: Repurposed Pharmacotherapies for Genetic Vasculopathies

Kocsy, K.; Wilkinson, H.; Sokolowska, Z.; Bolger, L. F.; Kumar, V.; Yan, A.; Felix-Ilemhenbhio, F.; McNeill, A.; Jain, S.; Van Agtmael, T.; Azzouz, M.; Majid, A.

doi:10.64898/2026.05.07.723462

bioRxiv · 10.64898/2026.05.07.723462

Targeting COL4A1-Related Small Vessel Disease: Repurposed Pharmacotherapies for Genetic Vasculopathies

Kocsy, K.·Wilkinson, H.·Sokolowska, Z.·Bolger, L. F.·Kumar, V.·Yan, A.·Felix-Ilemhenbhio, F.·McNeill, A.·Jain, S.·Van Agtmael, T.·Azzouz, M.·Majid, A.

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Abstract

COL4A1-related disorders cause early-onset stroke, intracerebral haemorrhage, visual impairment and kidney disease, often affecting children and young adults, yet no disease-modifying therapies exist. These disorders arise from pathogenic COL4A1 variants that disrupt type IV collagen and impair small-vessel integrity, leading to cerebral small-vessel disease and endothelial dysfunction. We performed a mechanism-guided screen in human brain endothelial cells using a CRISPR-engineered COL4A1 p.G755R line and patient-specific COL4A1 p.G773R iPSC-derived endothelial cells. Simvastatin, L-carnosine, and XPD-101 restored impaired endothelial proliferation, migration, and other markers of endothelial function, including transendothelial electrical resistance (TEER). In a Col4a1Svc/+ mouse model, simvastatin increased pre-weaning survival, improved functional behaviour and reduced cerebral microhaemorrhage burden. These findings identify mechanism-informed candidates that rescue COL4A1-mutant endothelial dysfunction in vitro, with simvastatin demonstrating in vivo efficacy, supporting prioritisation for further preclinical development.

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Kocsy, K., Wilkinson, H., Sokolowska, Z., Bolger, L. F., Kumar, V., Yan, A., Felix-Ilemhenbhio, F., McNeill, A., Jain, S., Van Agtmael, T., Azzouz, M., Majid, A.. 2026-05-11. Targeting COL4A1-Related Small Vessel Disease: Repurposed Pharmacotherapies for Genetic Vasculopathies. https://doi.org/10.64898/2026.05.07.723462

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