<qa>  How many sites are active in the OPTIMA study?This is the first trial of a Tri-National collaboration effort between the UK MRC, the Canadian CIHR and the VA CSP. The OPTIMA Trial was reviewed and approved by CSEC on October 12, 2000. The pre-kickoff meeting was held on March 21, 2001 in Washington, DC. The VA study kickoff meeting was held in Dallas, TX on May 16-18, 2001 and the Canadian kickoff was held in Toronto on May 29, 2001. The UK will have individual site initiation. As of October 17, 2005 there have been 357 patients enrolled in OPTIMA, at 64 sites in the three countries 279 in the VA, 41 in Canada and 37 in the UK. To date there are 64 sites actively participating in the study 24 in the VA, 19 in UK and 21 in Canada. Last date of patient follow-up was December 31, 2007. 