Combining two widely prescribed drug classes could provide the first effective treatment for early-stage Peyronie's disease, according to a new study published in The Journal of Sexual Medicine.
Peyronie's disease (PD) is caused by the development of fibrotic scar tissue within the penis, leading to pain, curvature, sexual dysfunction and, in many cases, significant psychological distress. It affects an estimated 10 per cent of men during their lifetime, but despite its prevalence, treatment options are limited, particularly in the early phase of the condition.
The study, carried out by Anglia Ruskin University (ARU) and University College London Hospital (UCLH), found that combining phosphodiesterase type 5 (PDE5) inhibitors such as sildenafil (Viagra) and tadalafil (Cialis) with selective oestrogen receptor modulators (SERMs), including tamoxifen, may slow or even stop disease progression when given early.
The clinical study, carried out by Professor David Ralph of UCLH, evaluated outcomes in 133 men diagnosed with acute Peyronie's disease who were treated with the drug combination for three months. Their results were compared with a smaller group of patients receiving standard care, which included giving vitamin E or no treatment at all. Standard care did not include surgery.
The study found 43 per cent of patients on the combination experienced an improvement in penile curvature, almost three times higher than in the standard‑care group (15 per cent).
At the start of treatment, 65 per cent of patients in the combination group reported pain during erections. After three months, that figure had fallen to just 1.5 per cent. By comparison, pain prevalence in the standard‑care group fell from 50 per cent to 27 per cent.
The clinical findings build on earlier laboratory work led by Professor Selim Cellek at ARU's Fibrosis Research Group . Over the course of several years, Professor Cellek's team screened 1,953 FDA‑approved drugs to identify compounds capable of blocking the transformation of fibroblasts into myofibroblasts, the key cells responsible for fibrosis. PDE5 inhibitors and SERMs emerged as particularly effective, and when used together demonstrated an effect greater than either drug alone.
Currently, there are no approved oral therapies proven to prevent early disease progression, forcing patients in the acute phase to wait until the condition stabilises before they can be offered treatments including injections or surgery.
Professor Cellek said: "Positive findings from this pilot clinical study validate our drug‑screening approach in the lab. It shows how repurposing well‑known medicines can accelerate progress in areas of unmet clinical need.
"Because both PDE5 inhibitors and SERMs are already widely used in clinical practice and have established safety profiles, the approach could be readily adoptable if confirmed in larger studies.
"These results suggest that early intervention targeting fibrosis could change how we treat Peyronie's disease. Repurposing existing drugs may allow us to move from managing symptoms to modifying the disease itself."
Professor David Ralph, Professor of Urology at UCLH, said: "This paper confirms the basic science research with regards to halting the progression of Peyronie's disease. In previous papers we have noted that tamoxifen and PDE5 inhibitors inhibit the transformation of fibroblasts into myofibroblasts and therefore contraction of the plaque.
"This has now been put into clinical practice where this paper shows that when tamoxifen and a PDE5 inhibitor are combined, there is statistically less progression of the disease and improvement in curvature compared to the control arm. This is where from bench to clinical practice prevails and hopefully now a prospective clinical trial can be initiated."
