Concerns raised informally about Russell Brand’s behaviour while he worked on several Channel 4 programmes were “not properly escalated or adequately addressed”, an investigation has found.

Brand, 49, was accused of rape, sexual assaults and emotional abuse as part of a joint investigation by Channel 4’s Dispatches programme, The Times and Sunday Times last year.

He has strongly denied all accusations about behaviour which allegedly took place between 2006 and 2013.

After the…