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Insulated glass is tempered, and cannot be drilled... it will shatter. So any egress between the panels would have to be through the spacer between the two panes.
There is a process that has been available for a few years and seems to be having success. The installer puts a valve in the spacer which allows the condensation to escape, but does not allow more moisture in.
Their website is http://www.getthefogoutnow.com. So far, the product is only available to professional installers, but as time goes by we hope that it will also be available to do-it-yourselfers!