Health campaigners challenging government policy in the High Court have been given a major costs boost. The group, led by Professor Stephen Hawking, is pursuing a judicial review against health secretary Jeremy Hunt and NHS England over plans to create accountable care organisations.

It said this week that the High Court has found against the government and allowed the group’s application for a cost capping order. The ruling, made by Mrs Justice Cheema-Grubb, means campaigners know that in the event of their losing that liability for costs would be no more than £160,000.

The judge also capped the defendants’ liability to pay claimants’ costs at £115,000 if the defence is unsuccessful. Tweeting under the username @JR4NHS, the claimant group said it had originally offered a cap of £100,000.

Cheema-Grubb said this was a case which met the statutory test of public interest, brought by responsible and public-spirited individuals, where a cap was required for defendant costs.

In a statement, the group said: ‘This judgment is fantastic news and a great relief. We now know that the money our supporters have donated will be enough to pay the defendants’ costs if we were to lose the JR, and with a bit more fundraising we have a good chance of being able to cover our lawyers’ "reduced fee" costs.’

The claim, led by three doctors, a former civil servant who co-chairs Keep Our NHS Public, and Hawking, has been funded by CrowdJustice. The group was represented in court by Peter Mant of 39 Essex Chambers, instructed by Kate Harrison of London firm Harrison Grant Solicitors.

Opponents of accountable care organisations say the partnership bodies linking hospitals, corporate services and councils are a step towards privatisation of the health service.

The Department of Health and Social Care described the claim as irresponsible scaremongering.