Formulations that can be used as photosensitizers for the treatment of cancer, such as bladder cancer, include polyvinylpyrrolidone-linked or polyvinylpyrrolidone-complex hypericin sodium salt. [Selection] Figure 1癌、例えば膀胱癌の治療に光増感剤として使用できる製剤は、ポリビニルピロリドン-結合またはポリビニルピロリドン-錯体ヒペリシンナトリウム塩を含む。【選択図】図1