Lausanne, Switzerland - Some 500 drug samples gathered at the Beijing Olympics will be retested for a new generation of the blood booster EPO and for insulin, the International Olympic Committee announced on Tuesday.

The IOC said in a press release that the retested samples are mainly from endurance events in cycling, rowing, swimming and athletics from January onwards. First results are to be announced by late March.

Around 400 samples will be tested for latest EPO version, known as CERA, in Lausanne and Paris. A new test for insulin is to be carried out on around 100 samples in Cologne.

The IOC had announced retests in October after the new CERA test was introduced. Several cyclists were caught doping with the substance at retests of Tour de France samples.

The IOC conducted a record 4,770 drug tests around the August 8-24 Games in Beijing. Six athletes were sanctioned after testing positive and several other cases are still pending. (dpa)