Three anti-doping charges have been filed against Nigerian sprinter Blessing Okagbare, who missed the Tokyo Olympic Games after a positive doping test, the Athletics Integrity Unit (AIU) said Thursday. The 32-year-old Okagbare, who has an Olympic silver medal in long jump from the 2008 Beijing Games, has been charged over a separate sample returning traces of EPO as well as the test for Human Growth Hormone which ruled her out of the 100 metre semi-finals Tokyo. Additionally she has been charged with a refusal to cooperate with the investigation into her case. Okagbare denies all charges and h…