Dr Andrew Wakefield, whose research linked the triple MMR vaccine with autism and bowel disease, has dropped his defamation case against Channel 4.

He issued proceedings against Channel 4, Twenty Twenty Productions and journalist Brian Deer over a programme in the Dispatches series entitled "MMR [What They Didn't Tell You]" which was broadcast on November 18, 2004.

But Dr Wakefield, who was being funded by the Medical Protection Society, discontinued the case at the start of this year, just after the end of the Christmas and New Year holiday period.

Kevin Sutcliffe, deputy head of news and current affairs at Channel 4, said: "Brian Deer's film was a powerful piece of investigative journalism which tackled a subject of enormous public importance.

"Dr Wakefield's decision to discontinue the libel proceedings is a complete vindication for both the Dispatches investigation and Brian Deer's dogged journalism."

Solicitor Amali de Silva, who led the team at law firm Wiggin LLP which represented Channel 4, said: "Channel 4 has always stood by the programme and its reporter, Brian Deer.

"As a result, the action was robustly defended from the outset and if Dr Wakefield had not decided to drop the action, Channel 4 and Wiggin fully intended to defend truth of the programme at trial."

Prash Naik, Channel 4's deputy head of legal and compliance, said: "Our decision to fight on with the action rather than capitulate to Dr Wakefield's demands to stay the proceedings is a credit to our legal team's astute tactical skills."

It is understood that no reason was given for the decision to drop the case.

But it means that Dr Wakefield and the Medical Protection Society, which was funding his action, will be liable for the costs run up by Channel 4, Twenty Twenty Productions and Mr Deer since the proceedings started early last year.

Dr Wakefield had claimed that the programme meant that he had spread fear that the MMR vaccine might lead to autism, and had acted dishonestly and for mercenary motives.

The case has already had three hearings in court. In October 2005, Dr Wakefield applied to have the proceedings stayed until the end of proceedings before the General Medical Council, the doctors'

disciplinary body.

That application - which would have meant that the case would probably not have come to court before late this year - was rejected by Mr Justice Eady, who said in a decision in November 2005 that the defendants had the right to have the case heard quickly, and that a delay would have a serious effect on Mr Deer's right to freedom of expression.

There were two further hearings in November this year, one involving disclosure of files relating to Dr Wakefield's own patients, and the other concerning disclosure of documents which were sent to Dr Wakefield in connection with the GMC proceedings.

In both cases Dr Wakefield was ordered to disclose the documents to the defendants, although there were also provisions to ensure that the patients' privacy and the confidentiality of medical records were protected.

The case could have proved extremely expensive had it gone to trial, because of the complexity of the issues surrounding the MMR vaccine, and because it would also have involved a number of expert witnesses.