LONDON, March 6 /PRNewswire/ -- Nationwide Building Society (http://www.nationwide.co.uk/savings/cash_isa/cash-isa.htm) has launched its new Champion ISA paying up to 2.50% gross p.a./AER variable and e-ISA paying 2.75% gross p.a./AER variable, as well as the launch of a number of new Fixed Rate ISA