2. Introduction
• A targeted therapy is defined as process of attacking a
biologically important process central to a hallmark of cancer or
disease.
(i) Some block the action of certain enzymes, proteins or other
molecules involved in growth of cancer cells
(ii) some types help the immune system to kill cancer cells; and
(iii) most targeted drugs are small-molecule drugs or monoclonal
antibodies.
• Blocks the growth of cancer cells by interfering with specific
targeted molecules.
3. • Targeted therapies act on specific molecular targets, were designed
to interact with their target, and are often cytostatic (block
proliferation), while standard conventional chemotherapy is
designed to kill rapidly dividing tumor cells, may also affect dividing
normal cells, and is cytotoxic (kill tumor cells).
• Unlike traditional chemotherapy, which kills both cancer cells and
healthy cells, targeted therapy drugs are designed to attack specific
molecules that are involved in cancer cell growth and survival
• Interfere with specific targeted molecules needed for
carcinogenesis and tumour growth rather than interfering with all
rapidly dividing cells
4. Targeted therapy in cancer cells is based on the inhibition of crucial
enzymes/pathways in a cancer cell, for which two definitions can be
formulated:
• Firstly, high activity of a pathway indicates that it may be essential
“to drive the tumor” and its inhibition stops growth of (or
sometimes kills) the cancer cell.
• Secondly, a low activity indicates that the activity may be rate-
limiting and essential [according to Weber a ‘key’ enzyme] for
growth, and therefore its inhibition may kill the cancer cell . In this
case, the enzyme may be considered as the “engine”.
13. The following four TKI drugs are approved as first-line treatment for
chronic phase CML:
• Imatinib mesylate (Gleevec®)
• Dasatinib (Sprycel®)
• Nilotinib (Tasigna®)
• Bosutinib (Bosulif®)
The following TKIs are approved
for the treatment of patients who
have received 2 or more TKIs or
who have the T315I mutation:
• Asciminib (Scemblix®)
• Ponatinib (Iclusig®)
37. Challenges of targeted therapy
Targeted therapy also has some challenges, including:
• Resistance: Cancer cells can develop resistance to targeted therapy
drugs over time.
• This means that the cancer cells can become resistant to the drug
and continue to grow and spread.
• Cost: Targeted therapy drugs can be very expensive.
• Limited availability: Some targeted therapy drugs are only available
for certain types of cancer.
38. Future of targeted therapy
• Researchers are constantly developing new targeted therapy drugs
and new ways to use targeted therapy drugs to treat cancer.
• Targeted therapy is a rapidly evolving field, and it is likely to play an
increasingly important role in cancer treatment in the future.
39. Conclusion
• Targeted therapy is a promising new approach to cancer treatment.
• It offers several benefits over traditional chemotherapy, including
more targeted killing of cancer cells, fewer side effects, and
improved survival rates.
• However, targeted therapy also has some challenges, such as
resistance, cost, and limited availability.
• Researchers are constantly developing new targeted therapy drugs
and new ways to use targeted therapy drugs to treat cancer.
• Targeted therapy is a rapidly evolving field, and it is likely to play an
increasingly important role in cancer treatment in the future.
40.
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