A day before the next installment of the so-called McLaren report investigating alleged state-sponsored doping in Russia, two Rio 2016 medalists have been stripped of their summer titles for failing doping tests.

Romanian weightlifter Gabriel Sincraian will lose his bronze in the men's 85kg weightlifting.

"Sincraian is found to have committed an anti-doping violation after testing positive for exogenous testosterone … during an in-competition doping control on August 12, 2016," a statement from the Court of Arbitration for Sport (CAS) in Lausanne, Switzerland, said.

Meanwhile, Russian boxer Misha Aloian's positive test results were upheld by the CAS - having tested positive for tuaminoheptane on August 21. He therefore loses his silver medal from the 52kg weight category.

Tuaminoheptane is a nasal decongestant drug designed to make people breathe more easily and is on the World Anti-Doping Agency's list of banned substances. Exogenous testosterone is synthetically-generated testosterone typically used to treat people with hormone deficiencies; again, it's on WADA's blacklist.

msh/jh (AFP, AP, dpa)