Update: New FDA approval of PARP inhibitor for maintenance therapy in ovarian cancer

Contents

APPROVAL AT A GLANCE

This update is about: 

On April 29, 2020, the U.S. Food and Drug Administration approved Zejula, (niraparib) as a first-line maintenance therapy for women with advanced ovarian cancer who have had a complete or partial response to chemotherapy. Zejula is a type of targeted therapy known as a PARP inhibitor. This approval applies to women both with, and women without a BRCA mutation.

What is maintenance therapy?

Maintenance therapy is a type of treatment that is given after chemotherapy treatment has been completed to try to keep the cancer from returning. The goal of maintenance therapy is to extend the length of time before a new recurrence emerges or even to turn a temporary remission into a long-term cure. Two types of agents—PARP inhibitors and bevacizumab—have been FDA approved for use as maintenance therapy in women with advanced ovarian, fallopian tube and primary peritoneal cancer. 

What is first-line treatment?

First-line treatment or therapy is the first treatment given for a disease such as cancer. Second-line treatments are used if the cancer doesn’t respond to first-line treatment or the cancer returns.  

After a woman has been diagnosed with ovarian cancer, first-line treatment is usually several months of chemotherapy. If her cancer responds well to treatment, she may stop treatment or begin maintenance therapy, unless her cancer comes back. If her cancer comes back, she will receive second-line treatment which maybe a new course of chemotherapy or another type of treatment. If her cancer does not respond, or comes back again, the following treatment would be called third-line. 

Why is this approval important?

Treatment of ovarian cancer remains a challenge. Most ovarian cancers respond well to chemotherapy; however, the majority will recur within five years. Until now, PARP inhibitors were only FDA approved for the following situations:

• As treatment for recurrent advanced ovarian cancer in women with a BRCA1 or BRCA2 mutation (found through genetic testing or tumor biomarker testing) who have received two or more previous lines of treatment
• As maintenance therapy for women with a BRCA1 or BRCA2 who have completed first-line (or higher) chemotherapy
• As maintenance therapy for women without a BRCA1 or BRCA2 mutation who completed at least second-line (or higher) chemotherapy.  

This is the first FDA approval that allows women with advanced ovarian cancer without a BRCA mutation to use a PARP inhibitor as maintenance therapy after first-line treatment.

Research findings:

FDA approval of Zejula was based on previous research from the PRIMA trial, which we reported in this XRAY review.

PRIMA looked at whether Zejula was safe and effective as maintenance therapy after a response to chemotherapy (before recurrence) in women with newly diagnosed ovarian cancer:

• Women who received Zejula after completing chemotherapy survived longer without their cancer coming back than women who received placebo after completing chemotherapy. This is known as progression-free survival. Women who received Zejula as maintenance therapy after completing treatment:
  • had an average progression-free survival time of almost 14 months compared to 8 months for patients who received a placebo after completing treatment.
  • had an overall survival rate after two years rate of 84 percent, compared to 77 percent for patients who received a placebo.
• Zejula caused severe, but not life-threatening side effects in 65 percent of patients enrolled in the study. The most common side effects seen with Zejula include:
  • low blood counts (e.g., anemia, low platelet count and low white blood cell count)
  • nausea
  • constipation
  • fatigue
  • headache
  • insomnia
  • vomiting
  • abdominal pain

Low blood cell counts were managed by reducing the dose of Zejula or taking a break from treatment.

What does this mean for me?

If you have been diagnosed with advanced ovarian cancer and you have had a complete or partial response to chemotherapy, you may want to talk to your doctor about maintenance therapy with Zejula or another PARP inhibitor.

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Posted 5/7/20

Reference

FDA approves niraparib for first-line maintenance of advanced ovarian cancer.

Disclosure

FORCE receives funding from industry sponsors, including companies that manufacture cancer drugs, tests and devices. All XRAYS articles are written independently of any sponsor and are reviewed by members of our Scientific Advisory Board prior to publication to assure scientific integrity.