Photodynamic therapy enhances the efficacy of gene-directed enzyme prodrug therapy

The results of the present study show that GDEPT and PDT interact in a synergistic manner over a range of prodrug concentration and tumor to transfected cell ratios. The degree of synergy was significant regardless if PDT treatment was given before or after 5-FC administration. The highest degree of interaction was observed though, when PDT was delivered prior to prodrug exposure.