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Phase II ABT-888 With Cyclophosphamide

Phase II Randomized Trial of ABT-888 in Combination With Metronomic Oral Cyclophosphamide in Refractory BRCA-Positive Ovarian, Primary Peritoneal, Ovarian High-Grade Serous Carcinoma, Fallopian Tube Cancer, or Triple-Negative Breast Cancer

Status
Completed
Phases
Phase 2
Study type
Interventional
Source
ClinicalTrials.gov
Registry ID
NCT01306032
Enrollment
124
Registered
2011-03-01
Start date
2011-01-12
Completion date
2016-12-15
Last updated
2017-04-26

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Ovarian Cancer, Primary Peritoneal Cancer, Serous Carcinoma Cancer, Triple-Negative Breast Cancer, Fallopian Tube Cancer

Keywords

PARP Inhibitor, BRCA Mutations, DNA Damage Repair, Pharmacodynamics, Metronomic Cyclophosphamide, Ovarian Cancer, Breast Cancer, Fallopian Tube Cancer, Peritoneal Cancer

Brief summary

Background: \- The experimental cancer treatment drug ABT-888 (Veliparib) works by preventing deoxyribonucleic acid (DNA) repair in tumor cells. Cyclophosphamide is a cancer treatment drug that works by causing DNA damage in cells, including cancer cells, resulting in cell death. However, because cyclophosphamide has strong and unpleasant side effects, researchers are interested in finding drugs that can be given in combination with cyclophosphamide that will allow a lower dose of cyclophosphamide to be given with similar effects. The combination of ABT-88 and cyclophosphamide may be an effective treatment for some types of cancer, such as certain kinds of breast or ovarian cancer and non-Hodgkin's lymphoma that often do not respond to standard therapies. Objectives: \- To evaluate the safety and effectiveness of ABT-888 and cyclophosphamide in ovarian and breast cancer and in non-Hodgkin's lymphoma that have not responded to standard treatments. Eligibility: \- Individuals at least 18 years of age who have been diagnosed with (1) (Breast cancer 1/2) BRCA1/2 ovarian cancer, primary peritoneal or ovarian high-grade carcinoma, or fallopian tube cancer; (2) triple-negative breast cancer (not responsive to hormone-related therapy); or (3) low grade non-Hodgkin's lymphoma. Design: * Participants will be screened with a full medical history and physical examination, blood and urine tests, and tumor imaging studies. Participants will be divided into two groups with different treatment subgroups. * Group 1: Participants who have BRCA-positive ovarian cancer, primary peritoneal or ovarian high-grade serous carcinoma, or fallopian tube cancer * Participants will receive either the combination of ABT-888 and cyclophosphamide, or cyclophosphamide alone. * Participants will take the study drug by mouth once a day for 21-day cycles of treatment, and will keep a diary to record drug doses and any side effects. * Participants will have clinic visits with blood and urine tests, imaging studies, and other examinations on days 1, 2, 7, and 14 of cycle 1, and on the first day of all other cycles. * Group 2: Participants who have triple-negative breast cancer or non-Hodgkin's lymphoma * Participants will receive either the combination of ABT-888 and cyclophosphamide, or cyclophosphamide alone. * Participants will take the study drug by mouth once a day for 21-day cycles of treatment, and will keep a diary to record drug doses and any side effects. * Participants will have clinic visits with blood and urine tests, imaging studies, and other examinations on days 1, 2, 7, and 14 of cycle 1, and on the first day of all other cycles. * Participants receiving only cyclophosphamide who show signs of disease progression after tumor imaging studies can receive the combination of ABT-888 with cyclophosphamide. * Treatment will continue as long as participants tolerate the drugs and the disease does not progress.

Detailed description

Background: * The poly (ADP-ribose) polymerase (PARP) family of enzymes is critical for maintaining genomic stability by regulating a variety of DNA repair mechanisms. * Individuals with deleterious mutations in the BRCA1 or BRCA2 tumor suppressor genes have an increased risk of developing breast and ovarian cancers due to impaired or defective DNA damage repair; these individuals have an increased susceptibility to DNA-damaging agents and PARP inhibitors. Inhibition of PARP inhibits the repair of DNA damage caused by alkylating agents such as cyclophosphamide. * Metronomic cyclophosphamide has demonstrated efficacy in several tumor types. The PARP inhibitor ABT-888 has been shown to potentiate the action of cyclophosphamide in xenograft models. This combination is well tolerated in a Phase I study and showing promising activity. Objectives: * Compare the response rate (complete response (CR) + partial response (PR)) of the combination of ABT-888 with metronomic oral cyclophosphamide to the response rate (CR+PR) of metronomic oral cyclophosphamide in patients with deleterious BRCA mutations and refractory ovarian cancer or patients with primary peritoneal or ovarian high-grade serous carcinoma or fallopian tube cancer. * Compare the response rate (CR+PR) of the combination of ABT-888 with metronomic oral cyclophosphamide to the response rate (CR+PR) of single-agent oral cyclophosphamide in patients with triple-negative metastatic breast cancer, stratified for deleterious BRCA mutation. * Compare the response rate (CR+PR) of the combination of ABT-888 with metronomic oral cyclophosphamide to the response rate (CR+PR) of single-agent metronomic oral cyclophosphamide in patients with refractory low-grade lymphomas. Secondary Objectives: \- Determine PAR levels in tumor biopsies, evaluate in archival tissue whether patients tumors have mutations in genes involved in DNA damage repair (e.g., BRCA/Fanconi anemia/protein 53 (p53)), perform exploratory gene expression profiling to correlate PARP messenger ribonucleic acid (mRNA) levels or BRCA mutation status with response to therapy, count circulating tumor cells (CTCs), and determine H2AX levels in CTCs and tumor biopsies (National Cancer Institute (NCI) clinical center only). Eligibility: -Adults with refractory BRCA-positive ovarian cancer, primary peritoneal or ovarian high-grade serous carcinoma, fallopian tube cancer, triple-negative breast cancer, or low-grade lymphoid malignancies (non-Hodgkin's lymphoma) whose disease has progressed following at least one line of therapy. Study Design: * This is a randomized, multi-histology Phase II trial with patients enrolled into 3 cohorts: BRCA-positive ovarian cancer or primary peritoneal or ovarian high-grade serous carcinoma or fallopian tube cancer (A); triple-negative breast cancer (B); or low grade non-Hodgkin's lymphoma (C). Patients in cohort A will be randomized to the combination of ABT-888 with metronomic oral cyclophosphamide or metronomic oral cyclophosphamide alone. Patients in cohort B will be randomized to the combination of ABT-888 with metronomic oral cyclophosphamide or metronomic oral cyclophosphamide alone. Patients in cohort C will be randomized to the combination of ABT-888 with metronomic oral cyclophosphamide or metronomic oral cyclophosphamide alone. * Cyclophosphamide (50 mg) and ABT-888 (60 mg) will be administered orally once a day, continuously in 21-day cycles.

Interventions

PARP enzymes are critical for maintaining genomic stability by regulating a variety of DNA repair mechanisms. Individuals with deleterious mutations in the BRCA1 or BRCA2 tumor suppressor genes have an increased risk of developing breast and ovarian cancers due to impaired or defective DNA damage repair; these individuals have an increased susceptibility to DNA-damaging agents and PARP inhibitors. Inhibition of PARP inhibits the repair of DNA damage caused by alkylating agents such as cyclophosphamide. Metronomic cyclophosphamide has demonstrated efficacy in several tumor types. The PARP inhibitor ABT-888 has been shown to potentiate the action of cyclophosphamide in xenograft models. This combination is well tolerated in a Phase I study and showing promising activity.

DRUGCyclophosphamide

Sponsors

National Cancer Institute (NCI)
Lead SponsorNIH

Study design

Allocation
RANDOMIZED
Intervention model
CROSSOVER
Primary purpose
TREATMENT
Masking
NONE

Eligibility

Sex/Gender
ALL
Age
18 Years to No maximum
Healthy volunteers
No

Inclusion criteria

* INCLUSION CRITERIA: * Patients with histologically documented: * BRCA-positive ovarian cancer (documented deleterious BRCA1/2 mutation or a BRCAPRO score of greater than or equal to 30%) * primary peritoneal or ovarian high-grade serous carcinoma or fallopian tube cancer (no requirement for BRCA status) * triple-negative breast cancer (documented estrogen receptor (ER) negative, progesterone receptor (PR) negative, and human epidermal growth factor receptor 2 (Her2/neu) negative from the original pathology report if considered adequate, or per The American Society of Clinical Oncology/College of American Pathologists (ASCO/CAP) guidelines (47, 48)) with metastasis to distant sites * Low-grade lymphoid malignancies (NHL), as described below, whose disease has progressed following at least one line of standard therapy: * Follicle center lymphoma, follicular or diffuse-recurrent/refractory * Marginal zone B-cell lymphoma: splenic, nodal, extranodal (this includes mucosa-associated lymphoid tissue (MALT)) - recurrent/refractory * Lymphoplasmacytic lymphoma - recurrent/refractory * Small lymphocytic lymphoma (SLL) (absolute lymphocytes count below 5,000) Pathology must be confirmed by the registering institution. For patients who are eligible for the study due to a history of BRCA1/2 mutation, documented evidence of their mutation status must be provided prior to enrolling on the study. * Patients must have measurable disease, defined as at least one lesion that can be accurately measured in at least one dimension (longest diameter to be recorded) as greater than or equal to 20 mm with conventional techniques or as greater than or equal to 10 mm with spiral computed tomography (CT) scan. * Any prior therapy or radiotherapy must have been completed greater than or equal to 4 weeks (greater than 6 weeks for nitrosoureas or mitomycin C) prior to enrollment on protocol, and the participant must have recovered to eligibility levels from prior toxicity. Patients must be greater than or equal to 2 weeks since any investigational agent administered as part of a Phase 0 study, and should have recovered to eligibility levels from any toxicities. * Patients who have had prior treatment with any PARP inhibitors are eligible unless the PARP inhibitor was administered in combination with cyclophosphamide. * Patients with bone metastases or hypercalcemia on bisphosphonate treatment are eligible to participate * Age greater than or equal to 18 years. Because no dosing or adverse event data are currently available on the use of ABT-888 in patients less than 18 years of age, children are excluded from this study, but may be eligible for future pediatric Phase I combination trials. * Karnofsky performance status greater than or equal to 70%. * Life expectancy greater than 3 months. * Patients must have adequate organ and marrow function as defined below: * absolute neutrophil count greater than or equal to 1,500/microL (mcL) * platelets greater than or equal to 100,000/microL (mcL) * total bilirubin less than 1.5 times institutional upper limit of normal * Aspartate aminotransaminase (AST) serum glutamic oxaloacetic transaminase (SGOT)/alanine aminotransaminase (ALT) serum glutamic pyruvic transaminase (SGPT) less than or equal to 2.5 times institutional upper limit of normal * creatinine less than 1.5 times institutional upper limit of normal OR --creatinine clearance greater than or equal to 60 mL/min for patients with creatinine levels greater than or equal to 1.5 times institutional upper limit of normal. * The effects of ABT-888 on the developing human fetus are unknown. For this reason and because cyclophosphamide hydrochloride is known to be teratogenic, women of childbearing potential and men must agree to use adequate contraception (abstinence; female use of hormonal methods, or barrier methods of birth control; male use of a condom) prior to study entry, for the duration of study participation, and for 3 months after completion of study. Because there is a risk for adverse events in nursing infants secondary to treatment of the mother with cyclophosphamide, breastfeeding should be discontinued while the patient is on this trial and for 30 days after completion of treatment on this trial. Should a woman become pregnant or suspect she is pregnant while participating in this study, she should inform her treating physician immediately. * Ability to understand and the willingness to sign a written informed consent document.

Exclusion criteria

* Women who are pregnant or breastfeeding. * Patients with uncontrolled intercurrent illness including, but not limited to, ongoing or active infection, symptomatic congestive heart failure, unstable angina pectoris, cardiac arrhythmia, or psychiatric illness/social situations that would limit compliance with study requirements. * Patients with germ cell and borderline ovarian epithelial tumors. * Patients who have received prior cyclophosphamide should not be excluded solely because of receiving prior cyclophosphamide. * Patients with history of central nervous system (CNS) metastases who have received treatment and who have been on stable doses of anti-seizure medicine and had no seizures x 3 months will be eligible. * Patients with gastrointestinal conditions that might predispose for drug intolerability or poor drug absorption (e.g., inability to take oral medication or a requirement for intravenous (IV) alimentation, prior surgical procedures affecting absorption, malabsorption syndrome, and active peptic ulcer disease) are excluded. Subjects with ulcerative colitis, inflammatory bowel disease, or a partial or complete small bowel obstruction are also excluded, as are any patients who cannot swallow the capsule whole. Capsules must not be crushed or chewed; nasogastric or gastrostomy tube (G-tube) administration is not allowed. INCLUSION OF WOMEN AND MINORITIES: -Men and women of all races and ethnic groups are eligible for this trial.

Design outcomes

Primary

MeasureTime frameDescription
Percentage of Participants With an Overall Response Ratean average of 126 days for ovarian; 71 days for TNBC; for crossover intervention, pts stayed on study for an avg of 134 days for ovarian; 50 days for TNBC.Complete response (CR) + partial response (PR)) of the combination of ABT-888 with metronomic oral cyclophosphamide to the response rate (CR+PR) of metronomic oral cyclophosphamide in patients with deleterious BRCA mutations and refractory ovarian cancer or patients with primary peritoneal or ovarian high-grade serous carcinoma or fallopian tube cancer. CR + PR was determined by the Response Evaluation Criteria in Solid Tumors (RECIST). CR is disappearance of all target lesions. Any pathological lymph nodes (whether target or non-target) must have reduction in short axis to \<10 mm). Partial response is at least a 30% decrease in the sum of the diameters of target lesions, taking as reference the baseline sum diameters.
Progression Free SurvivalOvarian cancer patients stayed on study for an average of 126 days and triple-negative breast cancer patients for an average of 71 days.Time to progression for each participant for the initial intervention.

Secondary

MeasureTime frameDescription
Number of Participants With Adverse Eventsup to 30 days following the last dose of study drug.Here is the number of participants with adverse events. For a detailed list of adverse events, see the adverse event module.
Change in Poly-ADP Ribose (PAR) Concentration Levels From BaselineAt baseline (t=0h) and 4h post drug administration (t=4h)PAR levels (in pg/μg protein) were assessed in peripheral blood mononuclear cells (PBMCs) by immunoassay to assess poly (ADP-ribose) polymerase (PARP) activity. Significant inhibition of PARP activity is associated with 50% or greater reduction in PAR levels.
Change in ϓH2AX- Positive Circulating Tumor Cells (CTCs) in Whole BloodAt baseline (t=0h) and 24h post drug administration (t=24h)Number of CTCs (evaluable defined as ≥ 6 CTCs) were measured in whole blood during the course of treatment to determine drug-induced deoxyribonucleic acid damage in tumor cells.
Number of Participants With Deleterious Mutations in DNA Repair GenesOptional tumor biopsies were performed prior to start of treatment (baseline) and 6 monthsGene expression profiling was performed in archival tumor tissue for a panel of 211 genes using deoxyribonucleic acid (DNA) array to determine deleterious mutations (i.e. nonsynonymous mutations at coding regions) of genes. Sequences were mapped to human genome reference hg19. Variants were identified with VarScan, annotated with AVIA, and masked to the exonic or exonic:splicing regions of the 211 interrogated DNA repair genes, with nonsynonymous/frameshift/stop-gain/stop-loss variants that have a population frequency of 1% or less in either 1000G (2014\_04) or the ExomeSequencingProject (ESP6500si\_all) with a minimum variant frequency of 10% and at least 20 reads. Lastly, variants were manually inspected for known platform and mapping errors.

Countries

Canada, United States

Participant flow

Pre-assignment details

Triple-negative breast cancer participants were enrolled but three did not start the study (two withdrew, 1 progressed).

Participants by arm

ArmCount
Triple-negative Breast Cancer: ABT-888 + Cyclophosphamide
Oral cyclophosphamide 50mg by mouth (PO) for 21 days and oral ABT-888 60mg by mouth (PO).
25
Triple-negative Breast Cancer: Cyclophosphamide Alone
Oral cyclophosphamide 50mg by mouth (PO) for 21 days.
20
BRCA-positive Ovarian Cancer: ABT-888 + Cyclophosphamide
Oral cyclophosphamide 50mg by mouth (PO) for 21 days and oral ABT-888 60mg by mouth (PO).
37
BRCA-positive Ovarian Cancer: Cyclophosphamide Alone
Oral cyclophosphamide 50mg by mouth (PO) for 21 days.
38
Non-Hodgkin's: ABT-888 + Cyclophosphamide
Oral cyclophosphamide 50mg by mouth (PO) for 21 days and oral ABT-888 60mg by mouth (PO).
2
Non-Hodgkin's: Cyclophosphamide Alone
Oral cyclophosphamide 50mg by mouth (PO) for 21 days.
2
Total124

Withdrawals & dropouts

PeriodReasonFG000FG001FG002FG003FG004FG005
Disease Progression/Crossoverother/symptomatic progression020200
Disease Progression/CrossoverWithdrawal by Subject000100
First InterventionAdverse Event101001
First InterventionDeath001000
First InterventionIneligible000001
First InterventionProgressive disease000020
First InterventionWithdrawal by Subject020100

Baseline characteristics

CharacteristicTriple-negative Breast Cancer: Cyclophosphamide AloneBRCA-positive Ovarian Cancer: ABT-888 + CyclophosphamideBRCA-positive Ovarian Cancer: Cyclophosphamide AloneNon-Hodgkin's: ABT-888 + CyclophosphamideNon-Hodgkin's: Cyclophosphamide AloneTriple-negative Breast Cancer: ABT-888 + CyclophosphamideTotal
Age, Categorical
<=18 years
0 Participants0 Participants0 Participants0 Participants0 Participants0 Participants0 Participants
Age, Categorical
>=65 years
4 Participants9 Participants9 Participants1 Participants0 Participants5 Participants28 Participants
Age, Categorical
Between 18 and 65 years
16 Participants28 Participants29 Participants1 Participants2 Participants20 Participants96 Participants
Age, Continuous53 years
STANDARD_DEVIATION 13
57 years
STANDARD_DEVIATION 10
58 years
STANDARD_DEVIATION 10
70 years
STANDARD_DEVIATION 24
56 years
STANDARD_DEVIATION 6
55 years
STANDARD_DEVIATION 10
57 years
STANDARD_DEVIATION 11
Ethnicity (NIH/OMB)
Hispanic or Latino
2 Participants1 Participants1 Participants0 Participants0 Participants1 Participants5 Participants
Ethnicity (NIH/OMB)
Not Hispanic or Latino
17 Participants36 Participants35 Participants1 Participants2 Participants22 Participants113 Participants
Ethnicity (NIH/OMB)
Unknown or Not Reported
1 Participants0 Participants2 Participants1 Participants0 Participants2 Participants6 Participants
Race (NIH/OMB)
American Indian or Alaska Native
0 Participants0 Participants0 Participants0 Participants0 Participants0 Participants0 Participants
Race (NIH/OMB)
Asian
2 Participants2 Participants1 Participants0 Participants0 Participants2 Participants7 Participants
Race (NIH/OMB)
Black or African American
3 Participants0 Participants0 Participants0 Participants0 Participants7 Participants10 Participants
Race (NIH/OMB)
More than one race
0 Participants0 Participants0 Participants0 Participants0 Participants0 Participants0 Participants
Race (NIH/OMB)
Native Hawaiian or Other Pacific Islander
0 Participants0 Participants0 Participants0 Participants0 Participants0 Participants0 Participants
Race (NIH/OMB)
Unknown or Not Reported
0 Participants0 Participants0 Participants0 Participants0 Participants0 Participants0 Participants
Race (NIH/OMB)
White
15 Participants35 Participants37 Participants2 Participants2 Participants16 Participants107 Participants
Region of Enrollment
Canada
3 Participants14 Participants15 Participants0 Participants0 Participants3 Participants35 Participants
Region of Enrollment
United States
17 Participants23 Participants23 Participants2 Participants2 Participants22 Participants89 Participants
Sex: Female, Male
Female
20 Participants37 Participants38 Participants1 Participants2 Participants25 Participants123 Participants
Sex: Female, Male
Male
0 Participants0 Participants0 Participants1 Participants0 Participants0 Participants1 Participants

Adverse events

Event typeEG000
affected / at risk
EG001
affected / at risk
EG002
affected / at risk
EG003
affected / at risk
EG004
affected / at risk
EG005
affected / at risk
EG006
affected / at risk
EG007
affected / at risk
deaths
Total, all-cause mortality
1 / 370 / 380 / 290 / 210 / 180 / 160 / 20 / 1
other
Total, other adverse events
28 / 3724 / 3829 / 2914 / 214 / 186 / 160 / 21 / 1
serious
Total, serious adverse events
3 / 370 / 380 / 292 / 210 / 181 / 160 / 21 / 1

Outcome results

Primary

Percentage of Participants With an Overall Response Rate

Complete response (CR) + partial response (PR)) of the combination of ABT-888 with metronomic oral cyclophosphamide to the response rate (CR+PR) of metronomic oral cyclophosphamide in patients with deleterious BRCA mutations and refractory ovarian cancer or patients with primary peritoneal or ovarian high-grade serous carcinoma or fallopian tube cancer. CR + PR was determined by the Response Evaluation Criteria in Solid Tumors (RECIST). CR is disappearance of all target lesions. Any pathological lymph nodes (whether target or non-target) must have reduction in short axis to \<10 mm). Partial response is at least a 30% decrease in the sum of the diameters of target lesions, taking as reference the baseline sum diameters.

Time frame: an average of 126 days for ovarian; 71 days for TNBC; for crossover intervention, pts stayed on study for an avg of 134 days for ovarian; 50 days for TNBC.

Population: Participants evaluable for response.

ArmMeasureValue (NUMBER)
Triple-negative Breast Cancer: ABT-888 + CyclophosphamidePercentage of Participants With an Overall Response Rate9.5 percentage of participants
Triple-negative Breast Cancer: Cyclophosphamide AlonePercentage of Participants With an Overall Response Rate5.6 percentage of participants
Triple-negative Breast Cancer: CrossoverPercentage of Participants With an Overall Response Rate0 percentage of participants
BRCA-positive Ovarian Cancer: ABT-888 + CyclophosphamidePercentage of Participants With an Overall Response Rate11.8 percentage of participants
BRCA-positive Ovarian Cancer: Cyclophosphamide AlonePercentage of Participants With an Overall Response Rate19.4 percentage of participants
BRCA-positive Ovarian Cancer: CrossoverPercentage of Participants With an Overall Response Rate3.4 percentage of participants
Primary

Progression Free Survival

Time to progression for each participant for the initial intervention.

Time frame: Ovarian cancer patients stayed on study for an average of 126 days and triple-negative breast cancer patients for an average of 71 days.

Population: Participants evaluable for response.

ArmMeasureValue (MEDIAN)
Triple-negative Breast Cancer: ABT-888 + CyclophosphamideProgression Free Survival3 Cycles of therapy
Triple-negative Breast Cancer: Cyclophosphamide AloneProgression Free Survival2 Cycles of therapy
Triple-negative Breast Cancer: CrossoverProgression Free Survival3 Cycles of therapy
BRCA-positive Ovarian Cancer: ABT-888 + CyclophosphamideProgression Free Survival3 Cycles of therapy
p-value: 0.034Log Rank
p-value: 0.68Log Rank
Secondary

Change in Poly-ADP Ribose (PAR) Concentration Levels From Baseline

PAR levels (in pg/μg protein) were assessed in peripheral blood mononuclear cells (PBMCs) by immunoassay to assess poly (ADP-ribose) polymerase (PARP) activity. Significant inhibition of PARP activity is associated with 50% or greater reduction in PAR levels.

Time frame: At baseline (t=0h) and 4h post drug administration (t=4h)

Population: Patients with PBMCs data pre- and post-drug administration, and with PAR levels above the lower limit of quantitation (LLOQ) of 23 pg/μg protein were analyzed.

ArmMeasureValue (MEAN)
Triple-negative Breast Cancer: ABT-888 + CyclophosphamideChange in Poly-ADP Ribose (PAR) Concentration Levels From Baseline-81 pg/μg protein
Triple-negative Breast Cancer: CrossoverChange in Poly-ADP Ribose (PAR) Concentration Levels From Baseline-88 pg/μg protein
BRCA-positive Ovarian Cancer: ABT-888 + CyclophosphamideChange in Poly-ADP Ribose (PAR) Concentration Levels From Baseline-74 pg/μg protein
BRCA-positive Ovarian Cancer: CrossoverChange in Poly-ADP Ribose (PAR) Concentration Levels From Baseline-85 pg/μg protein
Secondary

Change in ϓH2AX- Positive Circulating Tumor Cells (CTCs) in Whole Blood

Number of CTCs (evaluable defined as ≥ 6 CTCs) were measured in whole blood during the course of treatment to determine drug-induced deoxyribonucleic acid damage in tumor cells.

Time frame: At baseline (t=0h) and 24h post drug administration (t=24h)

Population: Patients with sufficient CTC counts (defined as ≥6 total CTCs) pre- and post-drug administration were analyzed.

ArmMeasureValue (MEAN)
Triple-negative Breast Cancer: CrossoverChange in ϓH2AX- Positive Circulating Tumor Cells (CTCs) in Whole Blood400 ϓH2AX- Positive CTCs
BRCA-positive Ovarian Cancer: ABT-888 + CyclophosphamideChange in ϓH2AX- Positive Circulating Tumor Cells (CTCs) in Whole Blood200 ϓH2AX- Positive CTCs
BRCA-positive Ovarian Cancer: CrossoverChange in ϓH2AX- Positive Circulating Tumor Cells (CTCs) in Whole Blood9.5 ϓH2AX- Positive CTCs
Secondary

Number of Participants With Adverse Events

Here is the number of participants with adverse events. For a detailed list of adverse events, see the adverse event module.

Time frame: up to 30 days following the last dose of study drug.

ArmMeasureValue (COUNT_OF_PARTICIPANTS)
Triple-negative Breast Cancer: ABT-888 + CyclophosphamideNumber of Participants With Adverse Events28 Participants
Triple-negative Breast Cancer: Cyclophosphamide AloneNumber of Participants With Adverse Events24 Participants
Triple-negative Breast Cancer: CrossoverNumber of Participants With Adverse Events29 Participants
BRCA-positive Ovarian Cancer: ABT-888 + CyclophosphamideNumber of Participants With Adverse Events14 Participants
BRCA-positive Ovarian Cancer: Cyclophosphamide AloneNumber of Participants With Adverse Events4 Participants
BRCA-positive Ovarian Cancer: CrossoverNumber of Participants With Adverse Events6 Participants
Non-Hodgkin's: ABT-888 & CyclophosphamideNumber of Participants With Adverse Events0 Participants
Non-Hodgkin's: Cyclophosphamide AloneNumber of Participants With Adverse Events1 Participants
Secondary

Number of Participants With Deleterious Mutations in DNA Repair Genes

Gene expression profiling was performed in archival tumor tissue for a panel of 211 genes using deoxyribonucleic acid (DNA) array to determine deleterious mutations (i.e. nonsynonymous mutations at coding regions) of genes. Sequences were mapped to human genome reference hg19. Variants were identified with VarScan, annotated with AVIA, and masked to the exonic or exonic:splicing regions of the 211 interrogated DNA repair genes, with nonsynonymous/frameshift/stop-gain/stop-loss variants that have a population frequency of 1% or less in either 1000G (2014\_04) or the ExomeSequencingProject (ESP6500si\_all) with a minimum variant frequency of 10% and at least 20 reads. Lastly, variants were manually inspected for known platform and mapping errors.

Time frame: Optional tumor biopsies were performed prior to start of treatment (baseline) and 6 months

Population: Patients with sufficient tumor content in archival tissue (defined as ≥70% tumor after macrodissection) were analyzed for genetic alterations in DNA repair genes by whole-exome sequencing.

ArmMeasureValue (COUNT_OF_PARTICIPANTS)
Triple-negative Breast Cancer: ABT-888 + CyclophosphamideNumber of Participants With Deleterious Mutations in DNA Repair Genes28 Participants
Triple-negative Breast Cancer: CrossoverNumber of Participants With Deleterious Mutations in DNA Repair Genes27 Participants

Source: ClinicalTrials.gov · Data processed: Feb 4, 2026