Linda Peanberg King with her son Axel who died / PA

A GP who worked for Harmoni, England's largest independent provider of out-of-hours care, says patients are at risk

Patients will be put at risk by privatised out-of-hours care, according to a GP and former clinical lead for Harmoni, the largest independent provider of urgent care services in England, after its doctors were criticised last week in an inquest over the death of a baby boy.

Harmoni was founded by a group of five London-based GPs in 1996. The founding quintet became millionaires last November when Harmoni was bought by Care UK in a £48m deal. Harmoni has grown rapidly, turning over £100m last year. It has won more than a quarter of the contracts for the new 111 service for people seeking non-emergency health-care advice.

Dr Fred Kavalier told the four directors of Harmoni in December 2010 of his "urgent concern about the quality and safety of the service Harmoni is providing". He listed several cases illustrating his concerns. In a prophetic warning to senior Harmoni directors Dr Bruce Websdale, Dr Angelique Edwards, Eileen Lock – one of the biggest shareholders – and the operations director, Faye Justice, Dr Kavalier said: "I fear it is only a matter of time before this low level of service leads to a serious clinical incident. I am writing this letter in the hope urgent action will be taken."

In a statement to The Independent on Sunday, Harmoni said it "responded fully to Dr Kavalier's concerns and our communication was sent by both email and recorded delivery letter on 11 March 2011". The company added: "We shared his concerns with both the primary care trust commissioners and the local medical committee. At no point has the LMC or PCT expressed any concerns about the issues he raised. Harmoni refutes absolutely any suggestion that concerns raised by any clinician, patient or commissioner have not been properly investigated."

Dr Kavalier used freedom of information requests to obtain Harmoni's response to the LMC and PCT regarding his concerns. Despite "extensive searches" nothing was produced, but Harmoni yesterday sent The IoS copies of the letters it says it sent, pointing out, "Clearly, these demonstrate that any concern is always thoroughly investigated."

St Pancras Coroner's Court heard last week the case of seven-week-old Axel Peanberg King. Dr Muttu Shantikumar, an out-of-hours doctor at the Harmoni clinic in Whittington Hospital, north London, run under contract to the NHS, ignored the pleas of Mrs Peanberg King for Axel to be seen as soon as possible, the inquest was told. After a Harmoni call handler listed Axel's case as "urgent", Dr Shantikumar downgraded it to "routine" after a one-minute phone conversation and left her waiting four hours for an appointment.

When Mrs Peanberg King from Islington, north London, attended the clinic with her baby dying of pneumonia she was made to wait in a queue. A representative of Harmoni told the court its investigation concluded that two of its doctors had not acted appropriately. The coroner Dr Shirley Radcliffe, recording a narrative verdict, said that Axel died following "wholly inadequate" decisions regarding his treatment.

Last March, five-week-old baby Sarae Thompson-Haynes died of whooping cough after her mother took her to the Harmoni clinic in Ipswich. She died six days later. The IoS asked Harmoni about Sarae's case but it declined to respond.

Dr Kavalier said a child's death was "the kind of serious incident I tried to bring to Harmoni's attention". He added: "It is what happens when services are fragmented and commercial interests become more important than patient care." Dr Kavalier resigned after six weeks. He added: "Despite Harmoni's claim they treat patients 'like family', in reality they treat them like rail passengers."

A Department of Health spokesman said: "It is a legal requirement for the NHS to make sure the right, high-quality out-of-hours services are in place for patients in their area. If this is not happening it is totally unacceptable and we expect the local NHS to take action immediately to improve their services."

Harmoni said in a statement: "The coroner was clear that she found no evidence of systems failure in the Harmoni service. No matter what the size of an organisation, and however robust its systems, it is not possible totally to eliminate the possibility of an individual human error or a single clinician's misjudgement."

Mr and Mrs Peanberg King said they were "considering all our options to prevent any other children from falling through the net".

The Harmoni millionaires

David Lloyd

When Harmoni saw off NHS Direct to win 12 contracts to run the new 111 non-urgent phone line last year, few people would have been happier than David Lloyd. He had been championing integrating out-of-hours care with NHS Direct for years.

In 2002, he said: "There are always going to be teething problems. But it works in the end."

The Harrow-based GP is estimated to have made at least £2.8m from the Care UK buyout.

Nizar Merali

Dr Merali is also estimated to have earned at least £2.8m from the Harmoni sale.

Adrian Richardson and Thomas Davies

The London GPs earned £1m each from the deal.

Ian Goodman

North-west London doctor Ian Goodman has championed NHS reforms. He chairs the Hillingdon clinical commissioning group and was a board director of Harmoni. Dr Goodman, with 16,000 shares, could have made up to £2.6m from the sale, it is thought.