STENDRA (avanafil) is often a selective inhibitor of cGMP-specific PDE5.
Avanafil is designated chemically as (S)-4-[(3-Chloro-4-methoxybenzyl)amino]-2-[2-(hydroxymethyl)-1-pyrrolidinyl]-N-(2- pyrimidinylmethyl)-5-pyrimidinecarboxamide and contains this structural formula:
Avanafil occurs as white crystalline powder, molecular formula C23H26ClN7O3 and molecular weight of 483.95 and is also slightly soluble in ethanol, practically insoluble in water, soluble in 0.1 mol/L hydrochloric acid. STENDRA, for oral administration, is as oval, straw tablets containing 50 mg, 100 mg, or 200 mg avanafil debossed with dosage strengths. In addition for the active ingredient, avanafil, each tablet provides the following inactive ingredients: mannitol, fumaric acid, hydroxypropylcellulose, low substituted hydroxypropylcellulose, calcium carbonate, magnesium stearate, and ferric oxide yellow.