Challenger Mortgage Management and Adelaide Bank have either sold, or expect this week to sell, mortgage-backed debt as issuers and investors agree terms.On Friday Challenger priced $298 million of securities that refinance one tranche of a 2004 bond sold by Interstar (an earlier name for the Challenger program).The bonds partly comprise low documentation loans and were priced at a spread of 48 basis points over the one month swap rate according to Insto. As a refinance, the loan pool is heavily seasoned at three years.Adelaide Bank is also in an advanced stage of marketing $350 million in mortgage-backed bonds through the latest in its Torrens series of trusts.According to Moody's Investors Service the portfolio consists entirely of fully documented loans with 13 months seasoning and weighted average current loan to value ratio of 64 per cent, which makes the bonds eligible for sale to the Reserve Bank of Australia under the revised arrangements for repurchase agreements.