The first in a new wave of deals to allow private firms to run GP services was signed last week.
By Nick Triggle
Health reporter, BBC News
Ministers want to encourage private sector involvement in primary care to fill gaps in areas which have traditionally struggled to attract doctors.
What does the future hold?
The government wants to see a range of GP providers
Derbyshire GP Elizabeth Barrett thought she had put together the ideal bid.
She had worked as a family doctor in the county for 20 years.
And as one of the partners at a nearby practice in the north east of the county, she thought she was perfectly positioned to run one of the Creswell primary care centre practices.
She proposed running the surgery along with a multi-disciplinary team involving nurses and a pharmacist - just the sort of model of care the government was calling for.
But a few days before Christmas she was told by local health bosses she had not won the contract.
Instead, it was offered to United Health Europe, part of a major US health firm.
"The whole process was mysterious," Dr Garrett said. "It was very hard to know what was happening with the bid and looking back I feel I never had a chance against such a big company.
"My fear now is that other GPs will struggle to win contracts because these big firms want to get involved. That will be a shame.
"Firms have to make profits for their shareholders and that leads to care being compromised, whereas GPs have been trained and worked for the NHS all their lives, the ethos is different."
United Health Europe was set to become the first private firm to be chosen to run GP services following the decision by ministers last year to fully open the market to private companies.
But the contract has not been finalised because a legal challenge by a local resident has meant the case is subject to a judicial review in the High Court.
Instead, it was left to east London health chiefs to become the first to put pen-to-paper in an expected new wave of deals.
Barking and Dagenham Primary Care Trust signed a £5m deal with Care UK, which runs a host of care homes and private hospitals, to provide GP services for over 7,000 patients.
The deal was brokered by the government as part of a bid to get GPs into under-doctored areas.
A handful of other contracts are also up for grabs in other parts of the country, including Liverpool and London.
To date, most private involvement in the NHS has been confined to providing non-emergency surgery.
There is some private involvement in GP care.
But this has been limited to organisations such as Chilvers McCrea, a company established four years ago by an NHS nurse and a GP which is now running more than 20 practices across the country.
Several other partnership arrangements have followed in their wake, but many see them as a different breed to the big firms as they are run by former NHS staff and remain essentially niche organisations specialising in primary care.
But with other contracts in the pipeline, doctors and campaigners fear the private sector is gearing up to monopolise the market.
GPs, nurses and voluntary organisations are free to bid for the contracts under the new flexible arrangements.
But the British Medical Association remains concerned NHS professionals are not competing on a level playing field.
Dr Richard Vautrey, of the BMA's GPs committee, said: "These multinationals have huge resources, it is hard for doctors to compete if they want to bid.
"What I want to see is primary care trusts giving doctors and other NHS staff support and training in how to bid for the contracts".
Paul Evans, of campaign group Keep Our NHS Public, is also concerned.
"The danger is that once these firms are in place, they will destabilise the local GP network.
"They may well compete for patients and discriminate against the ones with the most complex needs. That is not the way we want care to go."
"In years to come, we could see a handful of big firms controlling the market just as has happened with the care home market."
Many private firms sniffing around the GP market have been hesitant to declare their intentions.
However, it seems clear the money and opportunities involved have certainly sparked some interest.
Geoff Benn, group marketing director at Care UK, admitted the private sector would be bidding for more deals.
But he added: "To say it will be the privatisation of the NHS is a little ill-founded. I think there is scope for firms and current NHS doctors to work together.
"And I think private firms will bring something different to the market.
"I imagine we will see them diversify into different services, such as minor surgery, and filling gaps between the traditional GP service and hospital."
For the government, the concept of encouraging businesses to bid for contracts is not just driven by the desire to provide extra services.
Health Minister Lord Warner said many of the most deprived areas of the country had been "under-served for too long".
He said: "This new competition can only be good news for NHS patients as it will deliver a wider range of services open at more convenient times."