A process for synthesizing pirfenidone from bromobenzene having less thanabout 0.15% by weight dibromobenzeis disclosed. Also disclosed are processes of synthesizing pirfenidone withoutusing ethyl acetate or n-butanol, and pirfenidonehaving controlled levels of ethyl acetate, n-butanol, di(5-methyl-2-pyridinone)benzenes, and other impurities having specifiedretention times. Also disclosed are formulated dosage forms including thedisclosed pirfenidone.
