A Comprehensive Monograph on Avanafil (Stendra/Spedra): Pharmacology, Clinical Efficacy, and Safety Profile

I. Introduction and Drug Identification

Overview of Avanafil as a Second-Generation PDE5 Inhibitor

Avanafil is a potent, reversible, and highly selective inhibitor of phosphodiesterase type 5 (PDE5), an enzyme pivotal in the regulation of blood flow to the corpus cavernosum of the penis.[1] It is classified as a second-generation agent within its therapeutic class, developed for the oral, on-demand treatment of erectile dysfunction (ED) in adult males.[2] Avanafil's clinical profile is distinguished by two key pharmacological characteristics that were optimized during its development: a remarkably rapid onset of action, with clinical efficacy observed as early as 15 minutes post-administration, and a superior selectivity for the PDE5 isoenzyme compared to other phosphodiesterases.[5] These properties translate into a therapeutic option that offers patients greater spontaneity and a potentially more favorable safety and tolerability profile compared to first-generation PDE5 inhibitors.[4]

Nomenclature

To ensure precise identification, the various names and designations for Avanafil are outlined below:

• Generic Name: Avanafil [2]
• Brand Names: The drug is marketed under the brand name Stendra in the United States and Spedra in the European Union and other regions.[2]
• Chemical Names: The formal International Union of Pure and Applied Chemistry (IUPAC) name is 4- (3−chloro−4−methoxyphenyl)methylamino -2--N-(pyrimidin-2-ylmethyl)pyrimidine-5-carboxamide. Various chemical databases may list syntactical variants of this name.[3]
• Code Names: During its development phase, Avanafil was identified by the code name TA-1790.[9]

Development and Regulatory History