Maintenance Therapy: What Comes Next
- Maintenance therapy aims to prevent ovarian cancer from returning.
- Drugs called PARP inhibitors can be part of maintenance therapy.
- These drugs usually work best on cancers with certain genetic mutations.
- PARP inhibitors may cause side effects like nausea and low blood cell counts.
"Maintenance can mean a variety of things," says Dr. Michael Ulm, gynecologic oncologist at West Cancer Center in Memphis, Tennessee. "It depends on the genetic makeup of your ovarian cancer."
Diving Into Your Cancer's GenesRead More
Targeting Mutations With Treatment
If you do have BRCA mutations and/or HRD, your doctor can put you on a relatively new group of maintenance therapies called PARP inhibitors. These drugs capitalize on your cells' reduced DNA repair ability to prevent cancer cells from fixing themselves.
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.
Three PARP inhibitors are currently approved for ovarian cancer maintenance:
- Olaparib (Lynparza)
- Niraparib (Zejula)
- Rucaparib (Rubraca)
Your doctor will probably give you the drug they're most comfortable using, and the one they think you'll tolerate the best, Dr. Ulm says.
The big advantage to these drugs is that they might help you live longer. Research shows that taking a PARP inhibitor daily for two years "decreases the risk of the cancer coming back and increases survival," he adds.
PARP Inhibitor Side Effects: What to Expect
Any medication you take to manage your cancer has pros and cons. The pros are that the drug keeps your cancer at bay. The cons are its potential side effects. Because PARP inhibitors are a type of chemotherapy, they can damage healthy cells along with cancer cells.
Which side effects you end up having can vary, based on the drug you take. "Some cause a little more nausea, or affect bone marrow a little more," Dr. Ulm says. Fatigue is one of the most common side effects, affecting more than half of people who take these drugs.
These are some other side effects people who take PARP inhibitor drugs may experience:
- Belly pain
- Low numbers of red blood cells that carry oxygen to your body, called anemia
- Low numbers of platelets that help your blood to clot, called thrombocytopenia
Side effects are usually worst at the beginning of treatment, but they should gradually improve the longer you're on the medication. "I generally tell my patients the first month on maintenance therapy can be a little rocky," Dr. Ulm says. "You’re still trying to adjust the dose and figure out the right dose for the patient."
After the first month or two, you should level out and start to feel more comfortable on the medicine, he says. But if you do have any problems from your PARP inhibitor, reach out to your doctor for guidance. Chances are, your medical team can adjust the dose or prescribe medicines to manage your side effects.