DUBAI, Jan 18 (Reuters) - Bahrain's Gulf International Bank launched on Wednesday a $500 million Reg S bond with a final spread of 170 basis points over mid-swaps, according to a document issued by the banks arranging the deal and seen by Reuters.

The bank set initial pricing guidance for its bond earlier on Wednesday in the mid-swaps plus 180 basis points area but then tightened it to 170-175 bps over mid-swaps.

Citigroup, Dubai Islamic Bank, GIB Capital, HSBC, JP Morgan, Mizuho, National Bank of Abu Dhabi and Standard Chartered were involved in the transaction, with GIB Capital and JP Morgan as joint global coordinators.

(Reporting by Davide Barbuscia; editing by Jason Neely) ((Davide.Barbuscia@thomsonreuters.com;))