Cystoscopic application of RADA16 peptide for refractory haematuria from radiation cystitis

To present a novel technique for cystoscopic application of RADA16, a self-assembling peptide that promotes both haemostasis and healing within the irradiated bladder, and describe its efficacy for intractable haematuria from radiation cystitis.

A total of 15 patients who had failed standard treatment for haematuria from radiation cystitis were offered this novel treatment at Guy's Hospital, London and Cleveland Clinic London, UK between February and October 2024. A standard saline cystoscopy was performed under general anaesthetic and the bladder emptied. CO₂ insufflation of the bladder was performed and the RADA16 deployed over the area of radiation telangiectasia. This was left for 5 min and then the gas evacuated from the bladder. Patients were followed up for a minimum of 3 months for complications and re-bleeding.

In all, 14 of the 15 patients had significant reduction in their bleeding at 6 weeks. One patient with ongoing bleeding proceeded to salvage cystectomy. Two patients required further cystodiathermy and RADA16 application within 3 months. No other modified Clavien-Dindo ≥III complications occurred within 3 months. Patients who had a follow-up cystoscopy within 3 months of application showed significant regression of the radiation-induced telangiectasia with no evidence of bladder scarring or ureteric orifice obstruction.

Cystoscopic application of RADA16 shows promise for treating intractable haematuria from radiation cystitis. It is the first treatment option that potentially provides both haemostasis as well as promoting bladder healing and regression of radiation-induced telangiectasia.