Male erectile dysfunction(ED) affects more than 150 million men worldwide. Currently, treatment for ED predominantly consists of oral Phosphodiesterase type 5 (PDE5) inhibitors therapies. In mammals, 21 different PDE-encoding genes have been identified so far, classified in 11 families. Because of the insufficient selectivity, currently available PDE5 inhibitors also inhibit other PDE isozymes, affecting their target tissues (e.g., PDE1: heart; PDE6:retina; and PDE11: skeletal muscle), which in some cases can cause unwanted side effects and therapy discontinuation. As the unmet clinical needs with current PDE5 inhibitors, research is ongoing to develop even better and safer alternatives.

TPN729 is a drug candidate for the treatment of erectile dysfunction (ED). It is a novel, orally available PDE5 inhibitor with high activity and selectivity. TPN729 is about 3-fold more selective against PDE1 and 2.5-fold more selective against PDE6 than sildenafil, and about 500-fold more selective against PDE11 than tadalafil, showing a more balanced selectivity profile. Thus it is expected to have fewer side effects in comparison with current available PDE5 inhibitors. TPN729 also shows excellent in vivo potency, low toxicity and superior pharmacokinetic property.  

On June 25, 2013, TPN729 and its tablets, was approved by China Food and Drug Administration (CFDA) for clinical trial.

TPN729 is discovered and developed by Prof. Jingshan SHEN’s group and Prof. Hualiang JIANG’s groups (DDDC) in Shanghai Institute of Materia Medica (SIMM), The Center for Drug Safety Evaluation and Research of SIMM, the Center for Drug Metabolism Research of SIMM, and the College of Pharmaceutical Sciences (CPS) of Zhejiang University were also contributed to the preclinical research of TPN729 program. 

This program got supports from the National High-Tech R&D Program (863 Program), the National Science and Technology Major Project, Shanghai Science and Technology Commission and Shanghai Talent Development Fund.