Small Molecule Drug
Definición
A conventional drug with a low molecular weight (typically <900 daltons) that is produced by chemical synthesis. Small molecules can usually be taken orally, easily cross cell membranes, and can be exactly replicated as generic drugs. They represent approximately 90% of all marketed drugs.
Ejemplo
Aspirin (molecular weight 180 Da) is a classic small molecule drug, while the antibody trastuzumab (~148,000 Da) is a biologic — over 800 times larger.