There’s probably a much better way to do this, but here is a snippet of TSQL that will delete all of the table based Extended Properties on a SQL Server database. This might be useful for people migrating an on-premise SQL database to SQL Azure, which does not support extended properties.

DECLARE @prop_name  NVARCHAR(256)
DECLARE @table_name NVARCHAR(256)

DECLARE db_cursor CURSOR FOR
SELECT
ext.name,
tb.name
FROM
sys.extended_properties ext,
sys.tables tb
WHERE
ext.major_id = tb.object_id

OPEN db_cursor
FETCH NEXT FROM db_cursor INTO @prop_name, @table_name

WHILE @@FETCH_STATUS = 0
BEGIN
EXEC sp_dropextendedproperty
@name=@prop_name,
@level0type=N'SCHEMA',
@level0name=N'dbo',
@level1type=N'TABLE',
@level1name=@table_name

FETCH NEXT FROM db_cursor INTO @prop_name, @table_name
END

CLOSE db_cursor
DEALLOCATE db_cursor