An Example of an Early Targeted Cancer Therapy
One of the ways in which new means of targeting therapies to specific cells in the body - such as cancer cells - will arrive in the clinic more rapidly is for their developers to use existing approved drugs. That isn't necessarily the way to build objectively better therapies, but it will cost far less to run the regulatory gauntlet: "researchers have developed a novel system to simultaneously deliver a sustained dose of both an immune-system booster and a chemical to counter the cancer's secretions, resulting in a powerful therapy that, in mice, delayed tumor growth, sent tumors into remission and dramatically increased survival rates. The new immunotherapy incorporates well-studied drugs, but delivers them using nanolipogels (NLGs), a new drug transport technology the researchers designed. The NLGs are nanoscale, hollow, biodegradable spheres, each one capable of accommodating large quantities of chemically diverse molecules. The spheres appear to accumulate in the leaky vasculature, or blood vessels, of tumors, releasing their cargo in a controlled, sustained fashion as the spherule walls and scaffolding break down in the bloodstream. For the recent experiments, the NLGs contained two components: an inhibitor drug that counters a particularly potent cancer defense called transforming growth factor-β (TGF-β), and interleukin-2 (IL-2), a protein that rallies immune systems to respond to localized threats. ... The current study targeted both primary melanomas and melanomas that have spread to the lung, demonstrating promising results with a cancer that is well-suited to immunotherapy and for which radiation, chemotherapy and surgery tend to prove unsuccessful, particularly when metastatic." It's worth remembering that the medicine presently available in the clinic is not really available because it is better for patients, but rather because it is better at getting past regulatory hurdles - these two properties sometimes overlap, but are not the same at all.
Link: http://www.eurekalert.org/pub_releases/2012-07/nsf-ed_1070912.php