Byron Burger has received a £10m cash injection from existing investors as it struggles to improve trading.
The investment, reported in The Sunday Times, comes after the troubled chain entered into a company voluntary agreement (CVA) in 2018 and closed 19 branches.
Byron made a pre-tax loss of £55m on sales of £88m for the 12 months to June 2017.
In a bid to turnaround the company's fortunes, Byron introduced price cuts and a revamped menu, as well as the addition of vegan burgers and craft beers to the brand's offer.
The fresh injection of cash also comes less than a year after Byron secured £34.5m from private equity firm and existing backer Three Hills Capital Partners (THCP), which became the controlling shareholder as part of the restructuring.
Russell Hoare, chief financial officer, described the £10m lifeline as "a clear sign that the Byron chain is now on the right track".
He added: "We are making good progress across the board."
Founded in 2007 by restaurant group Gondola and Tom Byng, Byron grew to 34 sites before being sold to buyout firm Hutton Collins in 2013, in a deal worth about £100m. Its new owners said at the time that there was scope to grow the chain to more than 100 restaurants.
But Byron became a casualty of the ‘casual dining crunch' last year, alongside Jamie's Italian, Gourmet Burger Kitchen and Prezzo, thanks to a combination of higher wages, rising business rates and increased costs.
Former Wagamama boss Simon Cope resigned from his position as chief executive last December after less than two years in the role and following a string of departures in 2018 including those of chief operating officer Nick Young and marketing director Paul Coppin.Get The Caterer every week on your smartphone, tablet, or even in good old-fashioned hard copy (or all three!).