Tumor-Targeting NIR Dye-Drug Conjugates for Selective Chemotherapy

The patent uses a targeting ligand as an intermediary carrier that specifically binds to receptors on tumor cells. The chemotherapy drug is conjugated to this ligand, creating a targeted delivery system. The ligand acts as a mediator that guides the drug to the tumor site while protecting normal cells from exposure, thereby improving delivery efficiency and reducing off-target toxicity.

The patent creates a localized drug delivery system where the chemotherapy agent is activated only at the tumor site. The prodrug formulation remains inactive during circulation and is converted to the active form only after binding to tumor-specific receptors, ensuring that the toxic effect is localized to cancer cells while sparing normal tissues.

The patent employs a prodrug approach where the chemotherapy agent is administered in an inactive form that requires activation at the tumor site. This preliminary action allows the drug to be delivered systemically without causing immediate toxicity, and then activated locally at the tumor to achieve the desired therapeutic effect with minimal damage to normal cells.

The patent changes the chemical state of the chemotherapy agent from active to inactive through prodrug formulation. This parameter change allows the drug to circulate safely and then be converted to its active form only at the tumor site through enzymatic cleavage or other activation mechanisms, enabling effective tumor inhibition without systemic toxicity.