Sildenafil

Male erectile dysfunction (ED), a common reproductive system disease affecting more than 150 million men worldwide, has long seen its clinical demand not fully met. Sildenafil is a selective phosphodiesterase type 5 (PDE5) inhibitor. It reduces the degradation of cyclic guanosine monophosphate (cGMP) by inhibiting PDE5 activity, relaxes the smooth muscle of the corpus cavernosum, and promotes blood inflow to maintain an erectile state. In addition to treating male ED, it can also be used for the symptomatic treatment of pulmonary arterial hypertension, covering two groups of people: adult male ED patients and adult patients with pulmonary arterial hypertension.

The global sildenafil market size exceeded USD 6.5 billion in 2023, with a compound annual growth rate maintained at around 4.2%. After the patent cliff, generic drugs have rapidly increased their volume, and currently generics account for more than 70% of the overall market share. China is the world's largest producer of sildenafil active pharmaceutical ingredients (APIs), with its production capacity accounting for more than 65% of the global total production capacity. Since sildenafil was included in the centralized procurement in the domestic market in 2020, the terminal price has dropped by more than 90%, the accessibility of medication has been greatly improved, and the market size still maintains a steady growth of around 5% per year.

The original developer of sildenafil is Pfizer, with the original brand name "Viagra". Its core compound patent expired in the United States in 2019, and the compound patent in China expired in 2014. The main dosage forms of the original drug include 25mg, 50mg, 100mg tablets and 10mg/20mg dosage forms for pulmonary arterial hypertension, which have been included in the FDA Reference Listed Drug Catalog and China's *Catalog of Reference Preparations for Chemical Drugs*. At present, sildenafil APIs from more than 40 domestic enterprises have obtained Class A status through CDE registration, and the approved preparation varieties cover multiple dosage forms such as conventional tablets and orally disintegrating tablets. (Data as of October 2024, please refer to the official CDE website for the latest information)

CATO provides a full set of sildenafil impurity reference standards. Most products are in stock, and in-stock products ordered before 16:00 will be shipped on the same day. They can simultaneously meet the compliance requirements of multiple regulations such as the Chinese Pharmacopoeia and FDA, and provide stable and reliable reference standard support for the qualitative and quantitative analysis of impurities in the R&D, quality research and production processes of APIs.