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Background: Nausea and vomiting are common side effects of Trastuzumab Deruxtecan (T-DXd), but guidelines for optimal management were not initially available. This retrospective single-center study aimed at evaluating the efficacy of two antiemetic regimens in patients receiving T-DXd. Methods: Data from metastatic breast cancer patients receiving T-DXd were collected. Two groups were defined: patients treated with 5-HT3 receptor antagonists (RA) ± dexamethasone (5-HT3-group) and patients treated with a fixed oral combination of netupitant (NK1RA) and palonosetron ± dexamethasone (NK1 group). Physicians preferentially offered the NK1 regimen to patients at higher risk of nausea and vomiting based on internal recommendations. Only nausea and vomiting during cycles 1 and 2 were considered. Comparisons of nausea and vomiting by the antiemetic prophylaxis group were assessed using chi-square. Results: A total of 53 patients were included in the analysis. At cycle 1, 72% and 28% of patients received the 5-HT3 and NK1 prophylaxis, respectively. Overall, 58% reported nausea, with no differences between groups (58% vs. 60%; p = 0.832), but with a trend for lower grade in the NK1 group (33.3% G1; 26.7% G2) compared to the 5-HT3 group (23.7% G1; 31.6% G2; 2.6% G3). Vomiting was reported by 21% and 0% of patients in the 5-HT3 and the NK1 group, respectively (p = 0.054). Among the 15 patients in the 5-HT3 group with nausea at cycle 1 who escalated to NK1 at cycle 2, nausea decreased from 100% to 53% (p = 0.022) and vomiting decreased from 47% to 13% (p = 0.046). Conclusions: The NK1 regimen improved vomiting control at cycle 1 and, when introduced at cycle 2, significantly improved both nausea and vomiting. The biased NK1 selection for higher-risk patients may have dampened the differences between groups at cycle 1. These findings support enhanced control of T-DXd-related nausea and vomiting with NK1RA.
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BACKGROUND: In KEYNOTE-119 (ClinicalTrials.gov, NCT02555657), overall survival (primary end-point) was similar between pembrolizumab and chemotherapy in patients with previously treated metastatic triple-negative breast cancer (TNBC), although the pembrolizumab treatment effect increased with tumour PD-L1 expression. We report results of prespecified health-related quality of life (HRQoL) analyses from KEYNOTE-119. METHODS: Eligible patients were randomised 1:1 to pembrolizumab 200 mg Q3W intravenously for up to 35 cycles or treatment of physician's choice per local/country guidelines. Prespecified exploratory end-points were the change from baseline in HRQoL (EORTC QLQ-C30, QLQ-BR23) and to characterise utilities (EQ-5D-3L). Time to deterioration (TTD) was the time from start of treatment to first onset of a ≥10-point worsening from baseline. RESULTS: HRQoL analyses included 187 patients with tumour PD-L1 combined positive score (CPS) ≥10. Changes from baseline at 6 weeks (primary analysis time point) were directionally better with pembrolizumab versus chemotherapy for QLQ-C30 GHS/QoL (between-group difference in least-squares mean scores of 4.21 [95% CI, -1.38 to 9.80]), QLQ-C30 functional scales (physical, role, cognitive, social), QLQ-C30 symptom scales/items (fatigue, nausea/vomiting, dyspnoea, appetite loss), and QLQ-BR23 symptom scales/items (systemic therapy side-effects, upset by hair loss). Median TTD was directionally longer for pembrolizumab versus chemotherapy for QLQ-C30 QHS/QoL (4.3 versus 1.7 months), QLQ-C30 nausea/vomiting (7.7 versus 4.8 months), and QLQ-BR23 systemic therapy side-effects (6.1 versus 3.4 months). Minimal treatment differences were observed for other HRQoL end-points. CONCLUSIONS: HRQoL results were consistent with clinical outcomes and appeared to be driven by results for patients with tumour PD-L1 CPS ≥10.
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Calidad de Vida , Neoplasias de la Mama Triple Negativas , Humanos , Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos , Antígeno B7-H1 , Náusea , Neoplasias de la Mama Triple Negativas/tratamiento farmacológico , VómitosRESUMEN
Immune checkpoint blockade (ICB) benefits some patients with triple-negative breast cancer, but what distinguishes responders from non-responders is unclear1. Because ICB targets cell-cell interactions2, we investigated the impact of multicellular spatial organization on response, and explored how ICB remodels the tumour microenvironment. We show that cell phenotype, activation state and spatial location are intimately linked, influence ICB effect and differ in sensitive versus resistant tumours early on-treatment. We used imaging mass cytometry3 to profile the in situ expression of 43 proteins in tumours from patients in a randomized trial of neoadjuvant ICB, sampled at three timepoints (baseline, n = 243; early on-treatment, n = 207; post-treatment, n = 210). Multivariate modelling showed that the fractions of proliferating CD8+TCF1+T cells and MHCII+ cancer cells were dominant predictors of response, followed by cancer-immune interactions with B cells and granzyme B+ T cells. On-treatment, responsive tumours contained abundant granzyme B+ T cells, whereas resistant tumours were characterized by CD15+ cancer cells. Response was best predicted by combining tissue features before and on-treatment, pointing to a role for early biopsies in guiding adaptive therapy. Our findings show that multicellular spatial organization is a major determinant of ICB effect and suggest that its systematic enumeration in situ could help realize precision immuno-oncology.
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Inmunoterapia , Linfocitos T , Neoplasias de la Mama Triple Negativas , Humanos , Linfocitos B/inmunología , Biopsia , Linfocitos T CD8-positivos/inmunología , Granzimas/metabolismo , Antígenos de Histocompatibilidad Clase II/inmunología , Antígeno Lewis X/metabolismo , Terapia Neoadyuvante , Medicina de Precisión , Pronóstico , Ensayos Clínicos Controlados Aleatorios como Asunto , Linfocitos T/inmunología , Neoplasias de la Mama Triple Negativas/inmunología , Neoplasias de la Mama Triple Negativas/metabolismo , Neoplasias de la Mama Triple Negativas/terapiaRESUMEN
Breast cancer-associated genes 1 and 2 (BRCA1 and BRCA2) are tumor suppressor genes encoding a large protein that is involved in many essential biological processes. BRCA mutated patients show an increased risk to develop several malignancies, including cutaneous malignancies, although inconsistently across multiple studies. We carried out an observational study on the main dermatological and dermoscopic aspects in a population of patients with BRCA 1/2 mutations, to identify the main clinical and dermoscopical features in this class of patients. A total of 52 patients with BRCA mutations were included in the current analysis. Clinical, dermoscopical, and pathological data were obtained during the dermatologic visits. Out of the entire cohort, 67.3% of patients showed brown hairs and 63.5% of patients showed brown eyes, with phototype III as the most frequent phototype (69.2%). A total of 2.017 melanocytic lesions in all patients were analyzed; specifically, 40 patients (76.9%) showed a total number of nevi > 10, while regarding the main observed dermoscopic features, a prevalence of reticular pattern in 63% of cases was observed, followed by a mixed pattern in 19.2% of cases. Regarding the cutaneous examination, eruptive angiomas (eCAs) were the main dermatologic manifestations in 46.2% of patients. Out of 52 patients and during a follow-up of 24 months one patient developed an in situ melanoma. Interestingly, none of the patients with eCAs showed a TN > 10, highlighting an inverse correlation. To date, there is insufficient evidence to warrant increased surveillance in patients with BRCA mutations or with a positive family history for BRCA mutations, in the absence of standard cutaneous risk factors. Further studies with larger samples of patients are needed to better investigate dermatological and dermatoscopic features in BRCA mutation carriers.
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PURPOSE: The interplay between estrogen receptor (ER) and erbB tyrosine-kinase receptors (RTK) impacts growth and progression of ER-positive (ER+)/HER2-positive (HER2+) breast cancer and generates mitogenic signals converging onto the Cyclin-D1/CDK4/6 complex. We probed this cross-talk combining endocrine-therapy (fulvestrant), dual HER2-blockade (trastuzumab and pertuzumab), and CDK4/6-inhibition (palbociclib; PFHPert). EXPERIMENTAL DESIGN: Cytotoxic drug effects, interactions, and pharmacodynamics were studied after 72 hours of treatment and over 6 more days of culture after drug wash-out in three ER+/HER2+, two HER2low, and two ER-negative (ER-)/HER2+ breast cancer cell lines. We assessed gene-expression dynamic and association with Ki67 downregulation in 28 patients with ER+/HER2+ breast cancer treated with neoadjuvant PFHPert in NA-PHER2 trial (NCT02530424). RESULTS: In vitro, palbociclib and/or fulvestrant induced a functional activation of RTKs signalling. PFHPert had additive or synergistic antiproliferative activity, interfered with resistance mechanisms linked to the RTKs/Akt/MTORC1 axis and induced sustained senescence. Unexpected synergism was found in HER2low cells. In patients, Ki67 downregulation at week 2 and surgery were significantly associated to upregulation of senescence-related genes (P = 7.7E-4 and P = 1.8E-4, respectively). Activation of MTORC1 pathway was associated with high Ki67 at surgery (P = 0.019). CONCLUSIONS: Resistance associated with the combination of drugs targeting ER and HER2 can be bypassed by cotargeting Rb, enhancing transition from quiescence to sustained senescence. MTORC1 pathway activation is a potential mechanism of escape and RTKs functional activation may be an alternative pathway for survival also in ER+/HER2low tumor. PFHPert combination is an effective chemotherapy-free regimen for ER+/HER2+ breast cancer, and the mechanistic elucidation of sensitivity/resistance patterns may provide insights for further treatment refinement.
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Neoplasias de la Mama , Receptores de Estrógenos , Protocolos de Quimioterapia Combinada Antineoplásica/farmacología , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Neoplasias de la Mama/tratamiento farmacológico , Neoplasias de la Mama/genética , Neoplasias de la Mama/patología , Línea Celular Tumoral , Quinasa 4 Dependiente de la Ciclina/genética , Resistencia a Antineoplásicos/genética , Estrógenos/metabolismo , Femenino , Fulvestrant/farmacología , Fulvestrant/uso terapéutico , Humanos , Antígeno Ki-67 , Diana Mecanicista del Complejo 1 de la Rapamicina/genética , Receptor ErbB-2/metabolismo , Receptores de Estrógenos/metabolismoRESUMEN
The crosstalk between estrogen and HER2 receptors and cell-cycle regulation sustains resistance to endocrine therapy of HER2- and hormone receptor-positive breast cancer. We earlier reported that women with HER2 and ER-positive breast cancer receiving neoadjuvant dual HER2-block and palbociclib in the NA-PHER2 trial had Ki67 decrease and 27% pathological complete responses (pCR). We extended NA-PHER2 to Cohort B using dual HER2-block and palbociclib without fulvestrant and report here Ki67 drops at week-2 (mean change -25.7), at surgery (after 16 weeks, mean change -9.5), high objective response (88.5%) and pCR (19.2%). In Cohort C [Ki67 > 20% and HER2low (IHC 1+/2+ without gene amplification)], women also received fulvestrant, had dramatic Ki67 drop at week 2 (-29.5) persisting at surgery (-19.3), and objective responses in 78.3%. In view of the favorable tolerability and of the efficacy-predictive value of Ki67 drop at week-2, the chemotherapy-free approach of NA-PHER2 deserves further investigation in HER2 and ER-positive breast cancer. The trial is registered with ClinicalTrials.gov, number NCT02530424.
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BACKGROUND: Pembrolizumab showed durable antitumour activity and manageable safety in metastatic triple-negative breast cancer in the single-arm KEYNOTE-012 and KEYNOTE-086 trials. In this study, we compared pembrolizumab with chemotherapy for second-line or third-line treatment of patients with metastatic triple-negative breast cancer. METHODS: KEYNOTE-119 was a randomised, open-label, phase 3 trial done at 150 medical centres (academic medical centres, community cancer centres, and community hospitals) in 31 countries. Patients aged 18 years or older, with centrally confirmed metastatic triple-negative breast cancer, Eastern Cooperative Oncology Group performance status of 0 or 1, who had received one or two previous systemic treatments for metastatic disease, had progression on their most recent therapy, and had previous treatment with an anthracycline or taxane were eligible. Patients were randomly assigned (1:1) using a block method (block size of four) and an interactive voice-response system with integrated web-response to receive intravenous pembrolizumab 200 mg once every 3 weeks for 35 cycles (pembrolizumab group), or to single-drug chemotherapy per investigator's choice of capecitabine, eribulin, gemcitabine, or vinorelbine (60% enrolment cap for each; chemotherapy group). Randomisation was stratified by PD-L1 tumour status (positive [combined positive score (CPS) ≥1] vs negative [CPS <1]) and history of previous neoadjuvant or adjuvant treatment versus de-novo metastatic disease at initial diagnosis. Primary endpoints were overall survival in participants with a PD-L1 combined positive score (CPS) of 10 or more, those with a CPS of 1 or more, and all participants; superiority of pembrolizumab versus chemotherapy was tested in all participants only if shown in those with a CPS of one or more. The primary endpoint was analysed in the intention-to-treat population; safety was analysed in the all-subjects-as-treated population. This Article describes the final analysis of the trial, which is now completed. This trial is registered with ClinicalTrials.gov, number NCT02555657. FINDINGS: From Nov 25, 2015, to April 11, 2017, 1098 participants were assessed for eligibility and 622 (57%) were randomly assigned to receive either pembrolizumab (312 [50%]) or chemotherapy (310 [50%]). Median study follow-up was 31·4 months (IQR 27·8-34·4) for the pembrolizumab group and 31·5 months (27·8-34·6) for the chemotherapy group. Median overall survival in patients with a PD-L1 CPS of 10 or more was 12·7 months (95% CI 9·9-16·3) for the pembrolizumab group and 11·6 months (8·3-13·7) for the chemotherapy group (hazard ratio [HR] 0·78 [95% CI 0·57-1·06]; log-rank p=0·057). In participants with a CPS of 1 or more, median overall survival was 10·7 months (9·3-12·5) for the pembrolizumab group and 10·2 months (7·9-12·6) for the chemotherapy group (HR 0·86 [95% CI 0·69-1·06]; log-rank p=0·073). In the overall population, median overall survival was 9·9 months (95% CI 8·3-11·4) for the pembrolizumab group and 10·8 months (9·1-12·6) for the chemotherapy group (HR 0·97 [95% CI 0·82-1·15]). The most common grade 3-4 treatment-related adverse events were anaemia (three [1%] patients in the pembrolizumab group vs ten [3%] in the chemotherapy group), decreased white blood cells (one [<1%] vs 14 [5%]), decreased neutrophil count (one [<1%] vs 29 [10%]), and neutropenia (0 vs 39 [13%]). 61 (20%) patients in the pembrolizumab group and 58 (20%) patients in the chemotherapy group had serious adverse events. Three (<1%) of 601 participants had treatment-related adverse events that led to death (one [<1%] in the pembrolizumab group due to circulatory collapse; two [1%] in the chemotherapy group, one [<1%] due to pancytopenia and sepsis and one [<1%] haemothorax). INTERPRETATION: Pembrolizumab did not significantly improve overall survival in patients with previously treated metastatic triple-negative breast cancer versus chemotherapy. These findings might inform future research of pembrolizumab monotherapy for selected subpopulations of patients, specifically those with PD-L1-enriched tumours, and inform a combinatorial approach for the treatment of patients with metastatic triple-negative breast cancer. FUNDING: Merck Sharp & Dohme.
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Anticuerpos Monoclonales Humanizados/administración & dosificación , Protocolos de Quimioterapia Combinada Antineoplásica/administración & dosificación , Antígeno B7-H1/genética , Neoplasias de la Mama Triple Negativas/tratamiento farmacológico , Adolescente , Adulto , Anciano , Anticuerpos Monoclonales Humanizados/efectos adversos , Antígeno B7-H1/antagonistas & inhibidores , Femenino , Humanos , Persona de Mediana Edad , Metástasis de la Neoplasia , Supervivencia sin Progresión , Neoplasias de la Mama Triple Negativas/genética , Neoplasias de la Mama Triple Negativas/patología , Adulto JovenRESUMEN
Northern Italy has been one of the European regions reporting the highest number of COVID-19 cases and deaths. The pandemic spread has challenged the National Health System, requiring reallocation of most of the available health care resources to treat COVID-19-positive patients, generating a competition with other health care needs, including cancer. Patients with cancer are at higher risk of developing critical illness after COVID-19 infection. Thus, mitigation strategies should be adopted to reduce the likelihood of infection in all patients with cancer. At the same time, suboptimal care and treatments may result in worse cancer-related outcome. In this article, we attempt to estimate the individual risk-benefit balance to define personalized strategies for optimal breast cancer management, avoiding as much as possible a general untailored approach. We discuss and report the strategies our Breast Unit adopted from the beginning of the COVID-19 outbreak to ensure the continuum of the best possible cancer care for our patients while mitigating the risk of infection, despite limited health care resources. IMPLICATIONS FOR PRACTICE: Managing patients with breast cancer during the COVID-19 outbreak is challenging. The present work highlights the need to estimate the individual patient risk of infection, which depends on both epidemiological considerations and individual clinical characteristics. The management of patients with breast cancer should be adapted and personalized according to the balance between COVID-19-related risk and the expected benefit of treatments. This work also provides useful suggestions on the modality of patient triage, the conduct of clinical trials, the management of an oncologic team, and the approach to patients' and health workers' psychological distress.
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Betacoronavirus/patogenicidad , Neoplasias de la Mama/terapia , Infecciones por Coronavirus/prevención & control , Control de Infecciones/normas , Oncología Médica/organización & administración , Pandemias/prevención & control , Neumonía Viral/prevención & control , Adulto , Factores de Edad , Anciano , COVID-19 , Ensayos Clínicos como Asunto/organización & administración , Ensayos Clínicos como Asunto/normas , Continuidad de la Atención al Paciente/organización & administración , Continuidad de la Atención al Paciente/normas , Infecciones por Coronavirus/epidemiología , Infecciones por Coronavirus/transmisión , Infecciones por Coronavirus/virología , Femenino , Humanos , Control de Infecciones/organización & administración , Italia/epidemiología , Oncología Médica/normas , Persona de Mediana Edad , Neumonía Viral/epidemiología , Neumonía Viral/transmisión , Neumonía Viral/virología , Proyectos de Investigación/normas , Medición de Riesgo , Factores de Riesgo , SARS-CoV-2 , Telemedicina/organización & administración , Telemedicina/normasRESUMEN
BACKGROUND: Patients with HER2-positive breast cancer who have received two or more previous therapies for advanced disease have few effective treatment options. The monarcHER trial aimed to compare the efficacy of abemaciclib plus trastuzumab with or without fulvestrant with standard-of-care chemotherapy of physician's choice plus trastuzumab in women with advanced breast cancer. METHODS: This phase 2, three-group, open-label trial was done across 75 hospitals, clinics, and medical centres in 14 countries. Eligible patients were women aged 18 years or older, who had hormone receptor-positive, HER2-positive advanced breast cancer with unresectable, locally advanced, recurrent or metastatic disease, Eastern Cooperative Oncology Group performance status of 0 or 1, and who had previously received at least two HER2-targeted therapies for advanced disease. Patients were randomly assigned 1:1:1 to the abemaciclib, trastuzumab, and fulvestrant (group A), abemaciclib and trastuzumab (group B), or standard-of-care chemotherapy and trastuzumab (group C). Oral abemaciclib 150 mg 12 hourly was administered on days 1-21 of a 21-day cycle, intravenous trastuzumab 8 mg/kg on cycle 1 day 1, followed by 6 mg/kg on day 1 of each subsequent 21-day cycle, and intramuscular fulvestrant 500 mg on days 1, 15, and 29 and once every 4 weeks thereafter. Standard-of-care chemotherapy was administered as specified by the product label. Randomisation was by a computer-generated random sequence by means of an interactive web-response system and stratified by number of previous systemic therapies for advanced breast cancer and measurable versus non-measurable disease. The primary endpoint was investigator-assessed progression-free survival in the intention-to-treat population, first testing group A versus group C and, if this result was significant, then group B versus group C. Safety was assessed in all patients who had received at least one dose of study treatment. This trial is registered at ClinicalTrials.gov (NCT02675231) and is ongoing for long-term survival follow-up. FINDINGS: Between May 31, 2016, and Feb 28, 2018, 325 patients were screened, of whom 237 eligible patients were enrolled and randomly assigned to groups A (n=79), B (n=79), and C (n=79). Median follow-up was 19·0 months (IQR 14·7-25·1). The study met its primary endpoint, showing a significant difference at the prespecified two-sided α of 0·2 in median progression-free survival between group A (8·3 months, 95% CI 5·9-12·6) and group C (5·7 months, 5·4-7·0; HR 0·67 [95% CI 0·45-1·00]; p=0·051). No difference was observed between median progression-free survival in group B (5·7 months, 95% CI 4·2-7·2) and group C (HR 0·94 [0·64-1·38]; p=0·77). The most common grade 3-4 treatment-emergent adverse event in groups A, B, and C was neutropenia (21 [27%] of 78 patients, 17 [22%] of 77, and 19 [26%] of 72). The most common serious adverse events were: in group A, pyrexia (three [4%]), diarrhoea (two [3%]), urinary tract infection (two [3%]), and acute kidney injury (two [3%]); in group B, diarrhoea (two [3%]) and pneumonitis (two [3%]); and in group C, neutropenia (four [6%]) and pleural effusion (two [3%]). Two deaths were attributed to treatment: one due to pulmonary fibrosis in group B and one due to febrile neutropenia in group C. INTERPRETATION: The combination of abemaciclib, fulvestrant, and trastuzumab significantly improved progression-free survival versus standard-of-care chemotherapy plus trastuzumab while showing a tolerable safety profile. Our results suggest that a chemotherapy-free regimen might potentially be an alternative treatment option for patients with hormone receptor-positive, HER2-positive advanced breast cancer. FUNDING: Eli Lilly and Company.
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Aminopiridinas/administración & dosificación , Antineoplásicos Inmunológicos/administración & dosificación , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Bencimidazoles/administración & dosificación , Neoplasias de la Mama/tratamiento farmacológico , Antagonistas del Receptor de Estrógeno/administración & dosificación , Fulvestrant/administración & dosificación , Receptor ErbB-2/antagonistas & inhibidores , Receptores de Estrógenos/efectos de los fármacos , Trastuzumab/administración & dosificación , Anciano , Aminopiridinas/efectos adversos , Antineoplásicos Inmunológicos/efectos adversos , Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos , Argentina , Australia , Bencimidazoles/efectos adversos , Brasil , Neoplasias de la Mama/enzimología , Neoplasias de la Mama/mortalidad , Neoplasias de la Mama/patología , Progresión de la Enfermedad , Antagonistas del Receptor de Estrógeno/efectos adversos , Europa (Continente) , Femenino , Fulvestrant/efectos adversos , Humanos , Persona de Mediana Edad , América del Norte , Supervivencia sin Progresión , Inhibidores de Proteínas Quinasas/administración & dosificación , Inhibidores de Proteínas Quinasas/efectos adversos , Receptor ErbB-2/metabolismo , Receptores de Estrógenos/metabolismo , Receptores de Progesterona/metabolismo , República de Corea , Transducción de Señal , Factores de Tiempo , Trastuzumab/efectos adversosRESUMEN
PURPOSE: Metastatic triple-negative breast cancer (TNBC) is a phenotypic breast cancer subgroup with a very poor prognosis, despite standard treatments. Combined twice-weekly iniparib and gemcitabine/carboplatin (GC+tw-iniparib) showed benefit over gemcitabine/carboplatin in a randomized phase II trial, and a phase III was initiated comparing these regimens. The present phase II study was initiated to compare GC+tw-iniparib with a more practical once-weekly schedule (GC+w-iniparib) in TNBC. METHODS: Metastatic TNBC patients were randomized to receive iniparib weekly (11.2 mg/kg on days 1 and 8) or twice-weekly (5.6 mg/kg on days 1, 4, 8, and 11) with gemcitabine (1000 mg/m2) and carboplatin (area under the curve 2 on days 1 and 8), every 3 weeks. The primary endpoint was the overall response rate (ORR). Pharmacokinetics of iniparib and its two metabolites were analyzed. RESULTS: A total of 163 patients were randomized, 82 GC+w-iniparib and 81 GC+tw-iniparib. Demographic and baseline characteristics were well balanced. ORR was 34.1% (95% CI 23.9-44.4%) vs. 29.6% (95% CI 19.7-39.6%) and median progression-free survival was 5.5 months (95% CI 4.2-5.7) vs. 4.3 months (95% CI 3.0-5.8) for GC+w-iniparib and GC+tw-iniparib, respectively. Safety was similar across treatment arms in terms of event severity and type. Iniparib plasma concentrations and exposure were two-fold higher with w-iniparib compared to tw-iniparib. Iniparib and its metabolites were cleared rapidly with a terminal half-life of < 1 h, without accumulation. CONCLUSIONS: Despite a doubled maximum concentration with weekly iniparib, no detectable differences in safety or efficacy were observed between the weekly and twice-weekly administration schedules in this population. TRIAL REGISTRATION: ClinicalTrial.gov Identifier NCT01045304.