1. Japanese female participants aged 20 years or older on the day of signing informed
2. Voluntary written consent must be given before performance of any study related
procedure not part of standard medical care, with the understanding that consent may
be withdrawn by the participant at any time without prejudice to future medical care.
3. Participant must have a histologically diagnosed ovarian cancer, fallopian tube
cancer, or primary peritoneal cancer.
4. Participant must have a high-grade (or Grade 3) serous or high-grade predominantly
serous histology or known to have germline breast cancer gene mutation (gBRCAmut).
5. Participants must have completed at least 2 previous lines of platinum-containing
therapy (eg, carboplatin, oxaliplatin, or cisplatin):
Note: The last platinum regimen did not necessarily have to immediately follow the
next-to-last (penultimate) platinum regimen. For example, if a participant received a
non-platinum regimen between the penultimate platinum regimen and last platinum regimen,
she could have been eligible as long as she met all entry criteria.
1. For the penultimate platinum-based chemotherapy prior to study enrollment,
participants must have had platinum-sensitive disease after this treatment, defined as
achieving a response (CR or PR) and disease progression >6 months after completion of
her last dose of platinum therapy (documented 6 to 12 months or >12 months). Source
documentation was required.
2. For the last line of platinum-based chemotherapy prior to study enrollment:
i. Participants must have received a platinum-containing regimen for a minimum of 4 cycles.
ii. Participants must have achieved a partial or complete tumor response. iii. Following
the last regimen, participants must have had either.
1. CA-125 in the normal range, OR
2. CA-125 decrease by more than 90% during the last platinum regimen, and which was
stable for at least 7 days (ie, no increase >15%).
iv. Following the last regimen, participants could not have had any measurable lesion >2 cm
at the time of study enrollment.
c. Participants must have been enrolled within 8 weeks after completion of their final dose
of the platinum-containing regimen.
6. Participants must have performance status of ≤1 on the Eastern Cooperative Oncology
Group (ECOG) Performance Status Scale.
7. Participants must have adequate organ function as indicated by the following laboratory
1. Absolute neutrophil count (ANC) ≥1,500/μL.
2. Platelet count ≥100,000/μL.
3. Hemoglobin ≥9 g/dL.
4. Serum creatinine ≤1.5× institutional upper limit of normal (ULN) OR calculated
creatinine clearance ≥50 mL/minute, using the Cockcroft-Gault equation.
5. Total bilirubin ≤1.5×ULN OR direct bilirubin ≤1×ULN.
6. Aspartate aminotransferase (AST) and alanine aminotransferase (ALT) ≤2.5×ULN unless
liver metastases were present, in which case they had to be ≤5×ULN.
8. Participants must be able to take oral medications. 9. Female participants of
childbearing potential must be negative for pregnancy test (beta-human chorionic
gonadotropin [β-hCG]) within 7 days prior to receiving the first dose of study
10. Female participants who:
a. Are postmenopausal for at least 1 year before the screening visit, OR b. Are surgically
sterile, OR c. If they are of childbearing potential, agree to practice 1 highly effective
method of contraception and 1 additional effective (barrier) method at the same time, from
the time of signing the informed consent through 180 days after the last dose of study
drug, OR d. Agree to practice true abstinence, when this is in line with the preferred and
usual lifestyle of the participant. (Periodic abstinence [eg, calendar, ovulation,
symptothermal, postovulation methods], condoms only, withdrawal, spermicides only, and
lactational amenorrhea are not acceptable methods of contraception. Female and male condoms
should not be used together.)
1. Participants who have had drainage of ascites during last 2 cycles of last
2. Participants who have had palliative radiotherapy encompassing >20% of the bone marrow
within 1 week of the first dose of study treatment.
3. Participants who have any known, persistent (>4 weeks), Grade ≥3 toxicity from last
4. Participants who have symptomatic, uncontrolled brain or leptomeningeal metastases.
To be considered "controlled," central nervous system (CNS) disease must have
undergone treatment (eg, radiation or chemotherapy) at least 1 month prior to study
enrollment. The participant must not have had any new or progressive signs or symptoms
related to the CNS disease and must have been taking a stable dose of steroids or no
steroids (as long as these were started at least 4 weeks prior to enrollment] or no
steroids). A scan to confirm the absence of brain metastases at baseline was not
required. Participants with spinal cord compression might have been considered if they
had received definitive treatment for this and evidence of clinically stable disease
for 28 days.
5. Participants who have known hypersensitivity to the components of niraparib.
6. Participants who have had prior treatment with a known poly (adenosine diphosphate
[ADP]-ribose) polymerase (PARP) inhibitor.
7. Participant who have had treatment with any investigational products within 28 days or
5 half-lives (whichever was longer) before the first dose.
8. Participants who have had major surgery per Investigator judgment within 3 weeks of
the first dose. Participant must have recovered from any effects of any major surgery.
9. Participants who have diagnosis, detection, or treatment of invasive second primary
malignancy other than ovarian cancer ≤24 months prior to study enrollment (except
basal or squamous cell carcinoma of the skin that was definitively treated). Note:
Participants must not have any known history or current diagnosis of myelodysplastic
syndrome (MDS) or acute myeloid leukemia (AML), irrespective of the time for disease
10. Participants who are considered a poor medical risk due to a serious, uncontrolled
medical disorder, non-malignant systemic disease, or active, uncontrolled infection.
Examples include, but are not limited to, uncontrolled ventricular arrhythmia, recent
(within 90 days of the first dose) myocardial infarction, uncontrolled major seizure
disorder, unstable spinal cord compression, superior vena cava syndrome, small bowel
obstruction or other serious gastrointestinal disorder, or any psychiatric disorder
that prohibits obtaining informed consent.
11. Participants who have received a transfusion (platelets or red blood cells) within 4
weeks of the first dose of study treatment.
12. Participants who have received a live virus or bacterial vaccines within 4 weeks of
the first dose of study treatment.
13. Participants who have a history or current evidence of any condition, therapy, or lab
abnormality (including active or uncontrolled myelosuppression [ie, anemia,
leukopenia, neutropenia, thrombocytopenia]) that might confound the results of the
study, interfere with the participant's participation throughout the study period, or
study participation is not in the best interest of the participant.
14. Participants who are regular user (including "recreational use") of any illicit drugs
at the time of signing informed consent or have a recent history (within the past
year) of drug or alcohol abuse.
15. Participants who are pregnant or breast-feeding, or expecting to conceive within the
planned duration of the study.
NOTE: If a breast-feeding woman discontinue breast-feeding, she may be enrolled in the
16. Participants who are immunocompromised (participants with splenectomy are allowed).
17. Participants who have known human immunodeficiency virus (HIV) positive.
18. Participants who have known hepatitis B surface antigen (HBsAg) positive, or known or
suspected active hepatitis C virus (HCV) infection.
NOTE: Participants who are positive for hepatitis B core antibody (HBcAb) or hepatitis B
surface antibody (HBsAb) can be enrolled but must have an undetectable hepatitis B virus
(HBV) viral load. Participants who have positive hepatitis C virus antibody (HCVAb) must
have an undetectable HCV viral load.