Deglycyrrhizinated licorice is used for ulcers (gastric, duodenal, mouth), indigestion and reflux, and digestive tract issues. It retains its demulcent properties, as well as its action as an expectorant. Whole licorice is a powerful antiviral but deglycyrrizinated licorice is not.

Mills & Bone mention that both glycyrrhizin and licorice whole root is hepatic, indicating that DGL might be as well, but they don't specifically say. Kuhn & Winston say "several studies have assessed the efficacy of DGL with inconclusive results."

We found several studies on PubMed exploring the use of deglycyrrhizinated licorice for ulcers, and one on its antimicrobial effects: 

It seems that the only clinical trials that have been done on DGL are regarding ulcers, and as Kuhn & Winston said, there are mixed results. The AHPA handbook says: Licorice contains approximately 1 to 7% of the com- pound glycyrrhizin (Kondo et al. 2007). Many commercial products are standardized to 12% glycyrrhizin, and the European Pharmacopoeia species that licorice root should contain a minimum of 4% glycyrrhizin (Council of Europe 2001). SO, I wouldn't necessarily assume that DGL could be useful for anything other than (possibly) GI ulceration. It's tricky with these non-traditional preparations.