Polymer drug delivery systems were during last few decades proven to be efficient potential therapeutics for cancer treatment, especilly for the treatment of solid tumors, where they may take advantage of the Enhanced Permeability and Retention (EPR) effect for tumor-specific passive accumulation. Controlled release of anticancer drugs in cancer cells may be triggered by. e.g., cathepsin B activation after endocytosis. Endosomal proteases, especially cathepsins B and L, are known to be one of the key factors influencing some viral infections. For instance Ebola virus requires partial proteolysis of its surface glycoprotein for efficient endosome escape within its life cycle. We hypothesize that polymeric cathepsin B and L inhibitors may utilize advantages of polymer delivery systems for more effective treatment of viral infections with cathepsin inhibitors reducing systemic toxicity and increasing efficacy by targeted delivery of these inhibitors.

Keywords: Ebola virus; cathepsin; polymer; inhibitor