Dendrimers can be used to restrict the circulation of the drug in the body. This may avoid side effects, or may allow a higher dose of the drug to be administered than would otherwise be acceptable.
Damage to heart muscle can be a dose limiting toxicity for cancer drug doxorubicin (A). However, when doxorubicin is attached to a suitable dendrimer construct with preferential release of drug near a tumor , much less free drug reaches the heart muscle cells, and cardiac damage is reduced, (B), whilst drug efficacy is maintained at the tumour (D).
CAPTION: (A) Cardiac tissue damage can be a dose limiting toxicity for doxorubicin. (B) Image of undamaged cardiac muscle where negative control (PBS) is administered. (C) When DOX is conjugated to dendrimer, heart tissue no longer becomes damaged despite retention of efficacy against tumour as shown in xenograft study (D).