Ten of the 12 government-funded 'Portas Pilot' towns, which include Nelson and Stockport, have seen a fall in the number of occupied shop units, according to a report.
The towns were awarded a share of the £1.2 million High Street Innovation Fund, launched a year ago, as well as government support and access to retail guru Mary Portas following her review of the sector.
But a study by BBC Radio 4's You and Yours has found that in 10 of the 12 towns, more units closed than opened in the past year, with a loss of 95 units in all.
Only two towns showed signs of improvement, with Bedminster and Margate adding units in the past year.
In total, about 700 units closed, while fewer than 600 opened in their place, the report said.
Units include cafes, banks and pubs as well as shops, while vacancy rates apply only to shops.
The 12 pilot areas are Bedford, Croydon, Dartford, Greater Bedminster, Liskeard, Margate, Market Rasen, Nelson, Newbiggin-by-the-Sea, Stockport, Stockton-on-Tees and Wolverhampton.
The research was carried out by the Local Data Company.
The shop vacancy rates in the 12 pilot towns show improvements in some areas and decline in others, You and Yours reported.
In Newbiggin-by-the-Sea, Liskeard, Bedminster, Margate, Dartford, Bedford and Wolverhampton, the number of vacant shops has fallen, suggesting new businesses have arrived and populated previously empty ones. This may be due to prolonged use or temporary usage, such as a pop-up store.
The research also showed that Market Rasen, Nelson, Stockport, Croydon and Stockton-on-Tees all had more vacant shops, which can be seen as boarded-up or empty units.
Local Government Minister Don Foster said: "The main aim of the Portas Pilot scheme has been to harness the energy and enthusiasm of local people. High streets need to adapt to prosper, and this initiative brings together local councils, retailers and businesses to try out new ideas to drive their local economy.
"Over the last year this government has worked hard to help communities across the country boost their high street. We have lifted planning restrictions to help landlords make better use of their empty properties, and cut business rates for small shops.
"This is a long term project, but pilots up and down the country are already showing what is possible, from Braintree developing parking initiatives, to Market Rasen backing an award-winning local market, and we want to see positive action being taken by every town centre team.
"The anniversary of the pilots does not signal the end of government support, it is just the start. We have set up the Future High Streets Forum, made up of leading figures from the retail industry, to drive forward ideas and policies that will help high streets thrive and prosper."
Ms Portas told You and Yours: "There is no simple solution to the crisis on our high streets. There are no quick fixes but 400 towns up and down the country are working on different plans to try and reinvigorate their high street.
"Let's celebrate their achievements so far and learn and share ideas. Real change will take time."
Labour's spokeswoman on high streets, Roberta Blackman-Woods, said: "The fact is the Portas Pilots have struggled to deliver the high street renaissance that the Government promised because they have not been given enough practical support from Eric Pickles and his ministers to use the money awarded to them efficiently and effectively in support of their local economy.
"Too many high street shops are disappearing or turning into yet another payday lender or betting shop. That is why Labour wants to give more power to communities everywhere to shape their high streets."