Poly ADP-ribose polymerase (PARP) inhibitors are a promising development in the treatment of several cancers that have a high risk of recurrence, including ovarian cancer. Multiple clinical studies show that PARP inhibitors can delay ovarian cancer recurrence and help women with advanced disease live longer without the disease growing or returning. Although we are hopeful that PARP inhibitors may also have curative properties, more research is needed.
What are PARP inhibitors?
PARP inhibitors are a form of targeted therapy, a type of cancer treatment that uses special drugs to identify and disable the inner workings of cancer cells while minimizing disruption to normal, healthy cells. This contrasts with traditional methods such as chemotherapy and radiation therapy, which aim to destroy cancer cells through less selective cancer-fighting drugs or radiation, respectively. PARP inhibitors are a group of drugs that come in pill or capsule form and are taken daily by mouth.
How do PARP inhibitors work?
PARP inhibitors work by blocking a specific protein that helps repair DNA damage, such as the damage due to inherited or acquired problems in the cancer cell that disable the normal ability to repair DNA. This action can prevent damaged cancer cells from repairing themselves, potentially forcing them to die off.
PARP inhibitors appear to help ovarian cancer patients in two ways. The treatment’s impact is greatest in patients who have genetic changes, such as BRCA mutations. These genetic changes in DNA can be new to the cancer cell (acquired) or inherited. These same inherited changes can increase the risk of developing breast and ovarian cancer, but also make the cancers more sensitive to PARP inhibitors.
For an ovarian cancer patient with a BRCA mutation, PARP inhibitors may be used:
- To treat late-stage or recurrent ovarian cancer that harbor certain molecular or genetic features. BRCA mutations and other problems with “homologous recombination” repair are included.
- As a maintenance treatment following response to chemotherapy to delay cancer recurrence, which is common among women with advanced ovarian cancer
Overall, PARP inhibitors are viewed as a promising treatment that may slow the progression of ovarian cancer while prolonging the period between remission and recurrence.
What are the side effects?
The most common side effects of PARP inhibitors include:
- Loss of appetite
- Muscle or joint pain
- Abdominal pain
- Changes in taste
- Infrequent but associated toxicity is the development of a new blood cancer (leukemia) or problems producing blood cells (myelodysplasia).
Moffitt’s approach to PARP inhibitors and ovarian cancer treatment
Moffitt Cancer Center was among the first institutions in the world to give patients access to PARP inhibitors through clinical trials for women with recurrent ovarian cancer. Today, PARP inhibitors are widely viewed as the standard maintenance therapy for many ovarian cancers. Our relentless commitment to improving ovarian cancer treatment options is evidenced by our Comprehensive Cancer Center designation from the National Cancer Institute—currently, Moffitt is the only Florida-based cancer center to have earned this prestigious distinction.
Clinical breakthroughs like PARP inhibitors are just one reason why so many ovarian cancer patients choose Moffitt for their treatment. Our Gynecologic-Oncology clinic is home to a multispecialty team that focuses exclusively on cancers of the female reproductive system, and our specialists possess a unique level of experience addressing the most uncommon and complex malignancies. Collaborating together, our ovarian cancer treatment team creates highly individualized treatment plans for each patient based on her specific diagnosis and care preferences. Contact Moffitt at 1-888-663-3488 or complete a new patient registration form online to learn more about our ovarian cancer treatment services.
Moffitt is conducting additional clinical trials to build upon the initial success of PARP inhibitors, including trials that combine targeted therapies with other successful ovarian cancer treatments. Call 813-745-6100 or 1-800-679-0775 (toll-free) or submit a clinical trials inquiry form if you’d like to speak with a clinical trial navigator about what options may be available to you.
Medically reviewed by Dr. Robert Wenham, Department Chair, Gynecologic Oncology