Concerns about the behaviour of Russell Brand raised while he was working on several Channel 4 programmes were “not properly escalated or adequately addressed”, an investigation has found. The comedian and actor turned wellness guru was accused of rape, assault and emotional abuse as part of a joint investigation by Dispatches, the Times and Sunday Times that was published last year. Brand has denied all accusations about his behaviour, which relate to when he was at the height of his fame between 2006 and 2013. An investigation was launched by Banijay UK, which bought Endemol, the company commissioned by Channel 4 to produce the Big Brother spinoff shows EFourum, Big Brother’s Big Mouth, Kings Of Comedy and Big Brother: Celebrity Hijack, which Brand worked on between 2004 and 2006 and in 2008. Findings released by Karen Baxter, the head of investigations at the law firm Lewis Silkin, said no formal complaints were made about Brand during the programmes. “There were, however, concerns regarding Brand’s behaviour which were raised informally with senior members of staff, particularly in relation to him asking runners to obtain phone numbers of audience members, and female crew members feeling uncomfortable or intimidated by his behaviour while working in Bristol in 2004/2005. These concerns were not properly escalated or adequately addressed,” Baxter said. The findings also state that Brand was employed at a time when Channel 4 and Endemol knew he was a “recovering drug addict with a reputation for being ‘edgy’” and that “no particular safeguards were put in place to protect Brand, those who worked with him or those who otherwise came into contact with him”, including the audience. After the allegations, the BBC and Channel 4 removed material featuring Brand from their websites. He lost access to one of his main sources of income when YouTube stopped him generating money from his channel. In March a woman who had made allegations about Brand to Channel 4 in 2009 accused the broadcaster of a “whitewash” that she said had left her “disempowered and unsupported”. A week earlier the broadcaster had said it failed to properly investigate a serious allegation made against the actor and comedian 15 years ago. Channel 4’s internal investigation found that a 2009 complaint was “not passed up” the channel’s senior management chain “nor investigated as it ought to have been in accordance with the procedures in place at the time”. However, it said an internal investigation had found no evidence to suggest “there was knowledge within the channel” of claims made by four women in a Dispatches film before it was aired in September last year. On Friday Patrick Holland, the chief executive of Banijay UK, apologised to “anyone who was impacted” and felt “unable to speak up or that their voice was not properly heard”. In a statement, Holland said Endemol had support and escalation procedures in place at the time but “they were clearly not understood and adhered to to the degree we would expect today and were not as robust as our current UK and group-wide processes”. He added: “Industry protocols, duty of care and expectations of behaviour have vastly improved in recent years and continue to be reviewed and progressively updated on a regular basis. We are extremely sorry to anyone who was impacted by this behaviour and felt unable to speak up or that their voice was not properly heard.” Brand, 49, has been contacted for comment.