The United States Food and Drug Administration has approved Lynparza (olaparib) for certain forms of metastatic castration-resistant prostate cancer (mCRPC). This means, a person’s cancer has spread to other parts of their body and has not responded to surgery or drugs that lower testosterone. Olaparib is also used for the treatment of certain kinds of breast, ovarian, and pancreatic cancers.
Prostate cancer with HRR gene mutations
Specifically, olaparib is for adults whose cancer cells have mutations in genes called HRR (homologous recombination repair) genes. Your doctor will run a genetic test to determine if your cancer falls into this category. Some examples of HRR genes include genes called BRCA1, BRCA2, and ATM.
In order to take olaparib, people with prostate cancer must have previously tried taking either enzalutamide or abiraterone, which are other medications used to treat certain forms of prostate cancer. If a person’s cancer has progressed while taking these drugs, and they have an HRR gene mutation, they may be able to take olaparib.
How does olaparib work?
HRR genes are involved in repairing DNA and allowing cells to continue to grow and divide. When these genes are mutated, it can lead to uncontrolled cell growth and cancer. When cancer cells continue to grow and divide without being stopped, a person’s cancer can spread.
PARP (poly ADP-ribose polymerase) is a protein involved in this DNA replication and cell growth process. PARP inhibitors block this protein. This results in unrepaired damage to certain cells. Some of these cells include prostate cancer cells with HRR gene mutations. The damage is so severe, that these cancer cells may eventually die. Because olaparib targets these cells so specifically, it may be possible for the spread of prostate cancer to be slowed or stopped.
What are the possible side effects of olaparib?
For people taking olaparib, the most common side effects include:
- Nausea, vomiting, indigestion, and decreased appetite
- Cough, shortness of breath
- Headache or dizziness
- Low blood cell counts including red blood cells (anemia), certain white blood cells (can increase the risk of infection), and platelets (can increase the risk of bleeding and bruising)
- Changes in sense of taste
These are not all the possible side effects of olaparib. Talk to your doctor about what to expect or if you experience any changes that concern you during treatment with olaparib.
Things to know about olaparib
As with other drugs, there are less common but serious side effects that can occur with olaparib. Olaparib may cause issues with a person’s bone marrow. This includes a potential increased risk of developing blood cancers known as myelodysplastic syndrome (MDS) and acute myeloid leukemia (AML). If you notice any signs of these bone marrow issues, contact your doctor immediately:
- Severe weakness
- Shortness of breath
- Easy bruising
- Weight loss
- Frequent infections
Olaparib may increase a person’s risk of developing inflammation of the lungs. Your doctor will monitor you for this and may stop treatment if needed. If you notice any shortness of breath, cough, wheezing, or fever, contact your doctor as soon as possible. Since olaparib can impact blood cell levels, your doctor will also monitor these as well.
Olaparib may harm an unborn baby. Because of this, men being treated for prostate cancer who have female partners who could become pregnant, or who are pregnant, should utilize effective birth control methods while taking olaparib and for a period of time after stopping the drug. Patients should discuss appropriate birth control methods with their doctor.
Olaparib can increase a person’s risk of blood clots, including blood clots in the lungs (called a pulmonary embolism). Signs of a blood clot that need immediate medical attention include swelling or pain in a leg or arm, chest pain, changes in breathing, and fast heartbeat.
Talk to your doctor
Before starting olaparib for prostate cancer, tell your doctor if you:
- Have kidney or lung problems
- Have any other health conditions
- Have a partner who is pregnant or who may become pregnant
- Are taking any other medications (prescription and over-the-counter), vitamins, or supplements
Your doctor will determine the appropriate dosage and administration schedule for you. It is important to follow this schedule exactly as instructed, and not to stop taking olaparib or any other prescribed medications on your own. Patients should take their medication as prescribed by their doctor. Patients should talk to their doctor if they have any questions, or if they have questions regarding their olaparib regimen.
Read the prescribing information for olaparib to learn more.1,2