All About PARPS

Over the past few weeks many questions about PARP inhibitor use in the treatment ( front line, recurrent and maintenance) therapies for Ovarian Cancer were asked in many of the  private online groups that I participate in.  I can understand the questions and confusion because of the different PARPs available for women diagnosed with ovarian cancer - Olaparib ( Lynparza) , Niraparib ( Zejula) and Rucaparib (Rubraca) and their uses. 

In this blog post I will describe what a PARP inhibitor is, and provide all the FDA approval information and a few articles that compare the different types.

Let's start with this definition provided by the NCI.

PARP inhibitor
"A substance that blocks an enzyme in cells called PARP. PARP helps repair DNA when it becomes damaged. DNA damage may be caused by many things, including exposure to UV light, radiation, certain anticancer drugs, or other substances in the environment. In cancer treatment, blocking PARP may help keep cancer cells from repairing their damaged DNA, causing them to die. PARP inhibitors are a type of targeted therapy. Also called poly (ADP-ribose) polymerase inhibitor."

I'm more a visual person so here is a video by Dana Farber that you might find helpful.




Now lets look at each PARP and when , who and why it was approved. The FDA pages include references to the clinical trials that the approval was based on. Remember there are still clinical trials enrolling that may use a PARP in combination with other treatments. 

Olaparib:Lynparza

2014 
FDA Approval Summary: Olaparib Monotherapy in Patients with Deleterious Germline BRCA-Mutated Advanced Ovarian Cancer Treated with Three or More Lines of Chemotherapy. https://www.ncbi.nlm.nih.gov/pubmed/26187614

2017
On Aug. 17, 2017, the U.S. Food and Drug Administration granted regular approval to olaparib tablets (Lynparza, AstraZeneca) for the maintenance treatment of adult patients with recurrent epithelial ovarian, fallopian tube, or primary peritoneal cancer, who are in a complete or partial response to platinum-based chemotherapy.
 https://www.fda.gov/drugs/resources-information-approved-drugs/fda-approves-olaparib-tablets-maintenance-treatment-ovarian-cancer

Prescribing info
https://www.accessdata.fda.gov/drugsatfda_docs/label/2017/208558s000lbl.pdf

Niraparib:ZEJULA

2017
On March 27, 2017 , the U.S. Food and Drug Administration approved niraparib (ZEJULA, Tesaro, Inc.), a poly ADP-ribose polymerase (PARP) inhibitor, for the maintenance treatment of adult patients with recurrent epithelial ovarian, fallopian tube, or primary peritoneal cancer who are in complete or partial response to platinum-based chemotherapy.
https://www.fda.gov/drugs/resources-information-approved-drugs/niraparib-zejula

Here is additional information from an article in the AACR Journal
https://clincancerres.aacrjournals.org/content/24/17/4066

2019
On October 23, 2019,the Food and Drug Administration approved niraparib (ZEJULA, Tesaro, Inc.) for patients with advanced ovarian, fallopian tube, or primary peritoneal cancer treated with three or more prior chemotherapy regimens and whose cancer is associated with homologous recombination deficiency (HRD)-positive status. HRD is defined by either a deleterious or suspected deleterious BRCA mutation, or genomic instability in patients with disease progression greater than six months after response to the last platinum-based chemotherapy.
https://www.fda.gov/drugs/resources-information-approved-drugs/fda-approves-niraparib-hrd-positive-advanced-ovarian-cancer

Rucaparib: Rubraca

2016

On December 19, 2016, the U.S. Food and Drug Administration granted accelerated approval to rucaparib (RUBRACA, Clovis Oncology Inc.) for treatment of patients with deleterious BRCA mutation (germline and/or somatic) associated advanced ovarian cancer who have been treated with two or more chemotherapies.

https://www.fda.gov/drugs/resources-information-approved-drugs/rucaparib

2018
On April 6, 2018, the Food and Drug Administration approved rucaparib (Rubraca®, Clovis Oncology Inc.), a poly ADP-ribose polymerase (PARP) inhibitor, for the maintenance treatment of recurrent epithelial ovarian, fallopian tube, or primary peritoneal cancer who are in a complete or partial response to platinum-based chemotherapy.
https://www.fda.gov/drugs/resources-information-approved-drugs/fda-approves-rucaparib-maintenance-treatment-recurrent-ovarian-fallopian-tube-or-primary-peritoneal

This NCI  blog post PARP Inhibitors as Show Promis as Initial Treatment for Ovarian Cancer pulls together the use of PARPs for initial treatment.
https://www.cancer.gov/news-events/cancer-currents-blog/2019/parp-inhibitors-ovarian-cancer-initial-treatment

While this 30 minute webinar is geared toward medical professionals, it provides an overview of all three PARP inhibitors and their use.

If you have other resources you would like to share on PARP inhibitors please leave a link the the comment section and I will update this page.

Dee
Every Day is a Blessing!