Ovarian cancer is one of the most lethal gynecological cancers affecting women. According to the American Cancer Society, over 21,000 women are diagnosed with ovarian cancer each year in the United States alone. Fortunately, research and developments in ovarian cancer treatment have yielded several promising drugs that can help fight this disease. This article provides an overview of the major drug classes used to treat ovarian cancer at different stages.
Platinum-Based Chemotherapy
Platinum-based chemotherapy has remained the standard first-line treatment for ovarian cancer for decades. The two main platinum drugs used are cisplatin and carboplatin. These chemotherapy drugs work by damaging the DNA of cancer cells, which leads to their death. Cisplatin and carboplatin are usually given intravenously along with other chemotherapy drugs such as paclitaxel or pegylated liposomal doxorubicin. Platinum-based chemotherapy is highly effective in treating advanced stage ovarian cancer and improving survival rates when given after surgery to remove as much of the tumor as possible. However, these drugs can cause severe side effects like nausea, vomiting, nerve damage, hearing loss, and kidney damage.
Taxanes
Taxanes are another important class of chemotherapy drugs used for ovarian cancer. Paclitaxel and docetaxel work by interfering with cell division and stopping tumor growth. When given along with platinum-based chemotherapy, taxanes have shown to improve survival outcomes compared to platinum drugs alone. However, taxanes can also cause side effects such as nerve damage, bone marrow suppression, and allergic reactions. Unlike platinum drugs, taxanes can be given as maintenance therapy over a longer period of time after primary treatment to prevent cancer recurrence. Ongoing research aims to develop newer taxanes and taxane-based combinations with better tolerability profiles.
PARP Inhibitors
In recent years, PARP (poly ADP-ribose polymerase) inhibitors have emerged as a breakthrough in ovarian cancer treatment. PARP is a DNA repair protein and PARP inhibitors work specifically in cancers with BRCA gene mutations that impair DNA repair via homologous recombination. By inhibiting PARP, these drugs prevent cancer cells from repairing DNA damage caused during chemotherapy, forcing them to die. Three PARP inhibitors have been approved by the FDA – olaparib, rucaparib, and niraparib. PARP inhibitors significantly extend progression-free survival when given as maintenance therapy after chemotherapy for recurrent ovarian cancer. They also show efficacy in advanced BRCA-mutated ovarian, breast, and prostate cancers. PARP inhibitors cause mild side effects like fatigue, nausea, vomiting, and bone marrow suppression.
Angiogenesis Inhibitors
Drugs that target angiogenesis or new blood vessel formation are another class being evaluated for ovarian cancer. Tumor growth and metastasis depend on developing new blood vessels to receive nutrients and oxygen. Bevacizumab was the first angiogenesis inhibitor approved for use in ovarian cancer. It binds and inhibits vascular endothelial growth factor (VEGF), a protein instrumental in stimulating new blood vessel growth. In combination with chemotherapy, bevacizumab improves progression-free and overall survival in recurrent, platinum-resistant ovarian cancer compared to chemotherapy alone. However, it is associated with side effects like high blood pressure, bleeding, clotting problems, and impaired wound healing. Other anti-VEGF drugs like ramucirumab are being studied.
Immunotherapy
Recent scientific advances have led to the development and approval of immunotherapy drugs for certain cancers. However, ovarian cancer has remained rather resistant to immunotherapy due to factors like immunosuppressive tumor microenvironment. The PD-1 inhibitor pembrolizumab received accelerated FDA approval for dMMR/MSI-H (DNA mismatch repair deficient/microsatellite instability-high) solid tumors including ovarian cancer progressing after chemotherapy. Nivolumab, a PD-1 inhibitor, is also being evaluated in combination with other agents. Ongoing clinical trials are exploring different immunotherapy strategies involving checkpoint inhibitors, cancer vaccines, and chimeric antigen receptor T-cell therapy for ovarian cancer. Further research is warranted to maximize the potential of immunotherapy for more ovarian cancer patients.
Targeted Therapy
Besides conventional chemotherapy, targeted therapy aims to block specific molecular changes or signaling pathways that drive cancer growth. One example is the PARP inhibitor olaparib mentioned earlier. Others include inhibitors of PI3K/AKT/mTOR pathway, SRC inhibitors to block growth factor signaling, ANG2 inhibitors, MET inhibitors, and NOTCH inhibitors amongst several investigational agents in clinical trials for treating ovarian cancer. Depending on individual tumor genetics and molecular makeup, targeted therapy offers a personalized approach for managing certain ovarian cancer subtypes. Combination treatments integrating immunotherapy with targeted agents hold promise to maximize outcomes.
Conclusion
While ovarian cancer remains difficult to treat, significant strides have been made over the years in developing effective drug therapies. An improved understanding of disease biology and genetics should continue guiding research in this area. Combination regimens of chemotherapy, PARP inhibitors, angiogenesis inhibitors, and newer immunotherapy/targeted agents administered at appropriate stages offer currently the best approach. Supportive care measures also play an important role in managing side effects and enhancing patient comfort. With persistent work, we hope to find even more targeted and durable treatments to help conquer this devastating disease.
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- Source: Coherent Market Insights, Public sources, Desk research
2. We have leveraged AI tools to mine information and compile it
