PARP Inhibitors And Ovarian Cancer
- PARP inhibitors are now available to almost all women with ovarian cancer, even those without genetic mutations.
- These drugs respond best to BRCA1 and BRCA2 gene mutations, and these mutations are discovered through genetic testing.
- Researchers are still studying PARP inhibitors to see if they have additional benefits for women, and whether they would be useful in combination with other drugs.
The American Society of Clinical Oncology (ASCO) guidelines recommend PARP inhibitors be offered to women, with or without genetic mutations, who are newly diagnosed with stage III or IV ovarian cancer and have improved with chemotherapy.
What is a PARP inhibitor?Read More
How do you know if you are a good candidate for a PARP inhibitor?Ideally, ovarian cancer patients will undergo genetic testing to look for genetic mutations such as BRCA 1 or BRCA 2 positivity that are an indication that PARP inhibitors might be more effective for you. If you’re not found to have a hereditary mutation, genetic testing on the tumors specifically is usually carried out, as they could have still have the DNA defects that inform treatment decisions, even if they’re not in the rest of your body.
Some PARP inhibitors might have additional benefits if used in a combination with other drugs. Lynparza is approved in combination with Avastin (bevacizumab) for women with HRD. Avastin is a blood vessel growth inhibitor, which works by starving the tumor of vital nutrients needed to grow.
Dr. Amanika Kumar of the Mayo Clinic who spoke to SurvivorNet, cautioned that women still need to speak with their doctor to evaluate the benefit of taking a PARP inhibitor to extend life, because there are very real side effects due to the toxicity of the drug. "Patients with HRD (homologous recombination deficiency) have a far better response than those without and those with BRCA mutations even more so. It is on us as clinicians to help patients understand the risks and benefits of treatment. Patients that have no mutation or HRD may choose not to go on maintenance (in fact I recommend they don't) because there is real toxicity to these meds."