Chemotherapy drugs are known as much for their neg­a­tive side effects as for their ability to treat cancer. That’s because the small mol­e­cules used to kill tumor cells are also toxic to healthy cells. Tar­geted drug delivery, a method that came of age in the 1970s, aims to diminish chemotherapy’s side effects by deliv­ering drugs directly into the dis­eased cells, leaving the healthy ones unharmed.

One of the orig­inal scholars in this field is Vladimir Torchilin, Dis­tin­guished Pro­fessor of phar­ma­ceu­tical sci­ences at North­eastern Uni­ver­sity, who recently received the Journal of Drug Tar­geting’s 2012 life­time achieve­ment award. The journal is among the leading com­pendia of drug tar­geting schol­ar­ship, and its award rec­og­nizes sci­en­tists who have made excep­tional and sus­tained con­tri­bu­tions to drug delivery and tar­geting, according to the journal’s editor-​​in-​​chief, Saghir Akhtar of Kuwait University.

Torchilin is quick to assert that his achieve­ments in the field have been part of a larger, col­lab­o­ra­tive effort with con­tri­bu­tions from many researchers over sev­eral decades. He said the other recip­i­ents of the award are among his closest col­leagues and friends.

In recog­ni­tion of the award, the Journal of Drug Tar­geting will pub­lish a spe­cial issue high­lighting Torchilin’s work and the research it has inspired.

Torchilin, the director of Northeastern’s Center for Phar­ma­ceu­tical Biotech­nology and Nanomed­i­cine, is per­haps most well known for his work devel­oping lipo­somal car­riers, vesi­cles made of a lipid bilayer sim­ilar to the one that sur­rounds human cells. This is the type of car­rier used in one of the few tar­geted cancer treat­ments cur­rently on the market.

Torchilin said tumor cells have many more recep­tors for par­tic­ular mol­e­cules than healthy cells. For example, tumor cells can have at least a dozen times more recep­tors for folic acid than a non­cancerous cell. As a result, when car­riers like Torchilin’s lipo­somes are tagged on the sur­face with folic acid, they will end up binding to cancer cells much more often than healthy cells. This is the ratio­nale behind tar­geted cancer therapies.

Tar­geting defec­tive cells in dis­eases other than cancer is also very impor­tant. For example, myocar­dial infarc­tion is char­ac­ter­ized by car­diac cell damage. An ear­lier method devel­oped by North­eastern phar­ma­ceu­tical sci­ences pro­fessor Ban An-​​Khaw allows for tar­geted delivery of imaging agents to such cells for infarct visu­al­iza­tion, Torchilin explained. “But the absence of a cell could be tar­geted, too,” he added.

When endothe­lial cells lining the inner wall of a blood vessel are lost as a result of infec­tion or injury, thrombi and ath­er­o­scle­rotic lesions can form. Tar­geting cer­tain drugs to such areas can pre­vent thrombus for­ma­tion and assist endothe­lium re-​​growth.

Torchilin’s lab devel­oped yet another method for tar­geting drugs to spe­cific cell loca­tions. This is par­tic­u­larly rel­e­vant for dis­eases that are char­ac­ter­ized by fail­ures in spe­cific organelles, such as lyso­somal storage dis­eases, a col­lec­tion of about 40 inher­ited dis­eases that affect about one in every 5,000 to 10,000 people worldwide.

The lyso­some is often con­sid­ered the cell’s “recy­cling center” because it con­tains a variety of enzymes that work to break down unwanted par­ti­cles in the body and then turn them into use­able forms. Lyso­somal storage dis­eases result when one or more of these enzymes are absent because of a genetic defect. Torchilin’s method allows for the tar­geted delivery of the depleted enzymes directly to the lysosome.

The algo­rithm is the same for each indi­vidual dis­ease,” said Torchilin. “You just have to deliver dif­ferent enzymes.”

The cur­rent treat­ments for lyso­somal storage dis­eases are very expen­sive. “If you can develop a system that will allow you to uti­lize much less of the active enzyme, the delivery system will be sim­pler and more cost effec­tive and you could save more lives,” Torchilin said.