Cao Lei, the 75kg champion and Liu Chunhong, who won the 69kg category, were disqualified in January following a reanalysis of their drug tests.
Chen Xiexia, the 48kg gold medallist in Beijing, was also stripped of her title after the trio tested positive for the banned GHRP-2, a human growth hormone.
The Court of Arbitration for Sport confirmed Cao and Liu's disqualification, throwing out their appeal.