Target therapy and precision medicine

Timeline of the targeted therapies.[1]

Targeted therapy or molecularly targeted therapy is one of the major modalities of medical treatment (pharmacotherapy) for cancer, others being hormonal therapy and cytotoxic chemotherapy. As a form of molecular medicine, targeted therapy blocks the growth of cancer cells by interfering with specific targeted molecules needed for carcinogenesis and tumor growth,[1] rather than by simply interfering with all rapidly dividing cells (e.g. with traditional chemotherapy).
Targeted cancer therapies are expected to be more effective than older forms of treatments and less harmful to normal cells. Many targeted therapies are examples of immunotherapy (using immune mechanisms for therapeutic goals) developed by the field of cancer immunology. Thus, as immunomodulators, they are one type of biological response modifiers.
Since the very fist agents of Gleevec and Herceptin that are designed to inhibit certain cancer-related genes (e.g., ABL1 and ERBB2), many cancer-related genes have been subject to the drug development.
With many examples of successful targeted therapeutics such as EGFR inhibitors for lung adenocarcinomas and BRAF mutations for melanomas, it is evitable that more and more drugs will be developed and introduced into clinical fields.

History of immunotherapy.[2]

Targeted therapy has several problems such as the high progression/resistance rate and difficulties in identifying responders. However, with recently introduced immune checkpoint blockade treatments, targeted therapeutics will become one of essential treatment modalities in oncology.


[1] Nature Medicine Volume 17, Pages 297–303 (2011), Cancer genomics: from discovery science to personalized medicine.
[2] European Journal of Cancer Volume 81, Pages 116-129 (2017), Cancer immunotherapy: Opportunities and challenges in the rapidly evolving clinical landscape.