PARP inhibitors are a type of that work by blocking a protein used to repair damaged . They were initially developed to treat cancers in people with an inherited or mutation. Since then, research and additional approvals have expanded use of PARP inhibitors to more people and situations. There are four PARP inhibitors that have received approval for treating different types of advanced cancers.

Indications vary by:

type and of cancer: currently PARP inhibitors have been approved to treat breast, ovarian, pancreatic and cancers.
presence of a mutation or biomarker: have been approved in different settings for:
- people with certain inherited mutations.
- people with certain acquired mutations.
- people with certain tumor biomarkers.
- women with certain types of ovarian cancer, regardless of or status.
number of and response to prior treatments: have been approved in different settings for:
- platinum-sensitive or partially ovarian cancer.
- , (mCRPC).
- after chemotherapy.
- to treat progression or recurrence after a specific number of prior treatments.

Clinical trials studying PARP inhibitors in new settings or combinations are enrolling patients. As research continues, these approvals may expand to include treatment for additional cancers, earlier stages of cancer, people with other inherited mutations, and based on different tumor biomarkers.

Indications for PARP inhibitors

Cancer type	Indication	or inherited mutation
Cancer type	Indication	or inherited mutation	Lynparza olaparib	rucaparib	talazoparib	niraparib
breast cancer	For treatment of patients who have previously received chemotherapy, or hormone therapy for patients with hormone receptor ()-positive disease	Inherited or mutation and	X
breast cancer	For treatment of breast cancer	Inherited or mutation and			X
Early breast cancer at high risk for recurrence	after chemotherapy in people with an inherited or mutation. Although the has not yet approved this indication, several expert guidelines (including NCCN) now recommend this treatment option.	Inherited or mutation and	X
2-4 ovarian, or primary peritoneal cancer	, for women who had a complete or partial response to platinum chemotherapy	() testing	X (combined with Avastin)
2-4 ovarian, , or primary peritoneal cancer	maintenance therapy for women who had a complete or partial response to platinum chemotherapy	Inherited or acquired (tumor) mutation in or	X
2-4 ovarian, , or primary peritoneal cancer	maintenance women who had a complete or partial response to platinum chemotherapy	No inherited or acquired mutation or other tumor needed				X
Recurrent ovarian, or primary peritoneal cancer	Second-line (or later) for platinum-sensitive or partially sensitive cancer	No inherited or acquired mutation or other tumor needed	X	X		X
pancreatic cancer	maintenance therapy for patients whose disease has not progressed on at least 16 weeks of platinum-based chemotherapy	in or	X
castration-resistant cancer (mCRPC)	Men with mCRPC whose cancer has progressed following treatment with Xtandi () or Zytiga ()	in or or tumor mutation one of the following genes: ATM, , , , , CDK12, , FANCL, , RAD51B, , , RAD54	X
castration-resistant cancer (mCRPC)	Men with mCRPC who have been treated with androgen receptor-directed therapy and a taxane-based chemotherapy	Inherited or acquired (tumor) mutation in or		X

Last updated January 31, 2022