The news came as plans were revealed to invest an additional £10million of taxpayers' money in the hub that will see a revamp of the terminal building and duty free area.
Taxpayers have already stumped up £5.5m for the troubled Ayrshire airport since it was taken into public ownership last year, according to new figures, with a further £9.7m being set aside for the remainder of the 2014/15 financial year.
Deputy First Minister Nicola Sturgeon, reporting to the Scottish Parliament's Infrastructure Committee, said it would take several years to return the airport to profit but that it remained "long-term objective" of ministers to sell it back to the private sector.
Campaigners were left disappointed, however, by the decision against rebranding the airport as Robert Burns International.
Ms Sturgeon said she was persuaded there were "strong commercial reasons" to retain the Glasgow Prestwick name following the recommendations of Romain Py, the finance consultant hired to produce a £100,000 report on the airport's business options.
She said: "While it would be a very popular decision locally, we have to think in a broader context, and the feeling was we do not want to create confusion."
However, work has been commissioned to explore a Burns theme for the terminal, she added.
The Burns World Federation said it would continue its campaign, adding: "If George Best, Robin Hood and John Lennon are deemed worthy of being remembered Robert Burns should be remembered in Scotland as he is revered the world over."
Ms Sturgeon said £5.5m had been spent to date - including £1m in the current financial year - to prop up the airport, which was running at a monthly loss of about £800,000 when the Scottish Government bought it from Infratil for £1 last year.
She said the Government planned to spend a further £2.4m this year on upgrades that would help "reposition" the business and make the airport more attractive to passengers, including a complete refit of the airport's duty free lounge.
Taxpayers would also provide an additional £3m in operating support to keep the business afloat and £4.3m to clear a backlog of maintenance work, taking the total cost to taxpayers to more than £15m.
However, Ms Sturgeon insisted the funding represented loans, not subsidies, and the Government expects to recoup its investment once the airport returns to profit. A strategic vision document, based on Mr Py's findings, would be published this summer, she added.
However, Gordon Matheson, leader of Glasgow City Council, said: "I have serious concerns about how the Scottish Government can justify using up to £15m of taxpayers' money to support an airport without a viable business case, while not contravening State Aid rules. This has done nothing to reassure Glasgow that Government support for Prestwick will not jeopardise the success of Glasgow Airport."