SRS259 - A combination of off-label phosphodiesterase type 5 inhibitor and tamoxifen halts or reverses progression in acute Peyronie’s disease

Abstract Peyronie’s disease (PD) is characterised by fibrosis of the tunica albuginea and may cause penile pain, curvature, and erectile dysfunction. Current therapies are largely restricted to surgery or intralesional injection. We have previously shown that combining phosphodiesterase type 5 inhibitors (PDE5i; sildenafil, tadalafil) with selective oestrogen receptor modulators (SERMs; tamoxifen, raloxifene) exerts synergistic anti-fibrotic effects in experimental models of PD. Building on this, we compared tamoxifen plus a PDE5i with standard care in men with acute PD. Penile curvature and pain were assessed at baseline and after three months of treatment as part of a clinical audit. A total of 133 men with PD (mean disease duration 7.1 months) received an off-label regimen of tamoxifen (20 mg twice daily) combined with sildenafil (50 mg) or tadalafil (5 mg) daily for three months at a private hospital. In comparison, 26 men with PD (mean duration 7.8 months) received standard care (no treatment or vitamin E) for three months at a non-private hospital. Men who received combination therapy demonstrated significant improvement in penile curvature, while no meaningful change was observed with standard care. Pain improved in both groups but the reduction was greater in those treated with tamoxifen plus PDE5i. This is the first study to show that tamoxifen combined with a PDE5i may halt or reverse disease progression in men with acute PD.