A Phase II Trial of Selinexor (KPT-330) for Metastatic Triple-Negative Breast Cancer.

LESSONS LEARNED: Single-agent selinexor has limited activity in heavily pretreated patients with metastatic triple-negative breast cancer.Selinexor 60 mg by mouth twice weekly was generally well tolerated with a side-effect profile consistent with previous clinical trials.Future studies of selinexor in this population should focus on combination approaches and a biomarker-driven strategy to identify patients most likely to benefit. BACKGROUND: This phase II trial evaluated the safety, pharmacodynamics, and efficacy of selinexor (KPT-330), an oral selective inhibitor of nuclear export (SINE) in patients with advanced triple-negative breast cancer (TNBC). METHODS: This phase II trial was designed to enroll 30 patients with metastatic TNBC. Selinexor was given at 60 mg orally twice weekly on days 1 and 3 of each week, three of each 4-week cycle. The primary objective of this study was to determine the clinical benefit rate (CBR), defined as complete response + partial response + stable disease (SD) ≥12 weeks. RESULTS: Ten patients with a median age of 60 years (range 44-71 years) were enrolled between July 2015 and January 2016. The median number of prior chemotherapy lines was 2 (range 1-5). A planned interim analysis for the first stage per protocol was performed. Three patients had SD and seven had progressive disease. On the basis of these results and predefined stoppage rules, the study was halted. CONCLUSION: Selinexor was fairly well tolerated in patients with advanced TNBC but did not result in objective responses. However, clinical benefit rate was 30%, and further investigation of selinexor in this patient population should focus on combination therapies.

Oncolytic T-VEC virotherapy plus neoadjuvant chemotherapy in nonmetastatic triple-negative breast cancer: a phase 2 trial.

Talimogene laherparepvec (T-VEC) is an oncolytic virus hypothesized to enhance triple-negative breast cancer (TNBC) responses to neoadjuvant chemotherapy (NAC). This article describes the phase 2 trial of T-VEC plus NAC (ClinicalTrials.gov ID: NCT02779855 ). Patients with stage 2-3 TNBC received five intratumoral T-VEC injections with paclitaxel followed by doxorubicin and cyclophosphamide and surgery to assess residual cancer burden index (RCB). The primary end point was RCB0 rate. Secondary end points were RCB0-1 rate, recurrence rate, toxicity and immune correlates. Thirty-seven patients were evaluated. Common T-VEC toxicities were fevers, chills, headache, fatigue and injection site pain. NAC toxicities were as expected. Four thromboembolic events occurred. The primary end point was met with an estimated RCB0 rate = 45.9% and RCB0-1 descriptive rate = 65%. The 2-year disease-free rate is equal to 89% with no recurrences in RCB0-1 patients. Immune activation during treatment correlated with response. T-VEC plus NAC in TNBC may increase RCB0-1 rates. These results support continued investigation of T-VEC plus NAC for TNBC.

A Phase I Trial of Talimogene Laherparepvec in Combination with Neoadjuvant Chemotherapy for the Treatment of Nonmetastatic Triple-Negative Breast Cancer.

PURPOSE: Talimogene laherparepvec (TVEC) is an oncolytic herpes simplex 1 virus approved for treatment of melanoma. We hypothesized intratumoral TVEC may enhance response to neoadjuvant chemotherapy (NAC). This article reports the results of a trial combining NAC with TVEC for triple-negative breast cancer (TNBC). PATIENTS AND METHODS: Patients with stage II-III TNBC enrolled in a 3+3 phase I trial (NCT02779855) of two TVEC dose levels [DL; DL 1 = 106 plaque-forming units (PFU) × 5 doses; DL 2 = 106 PFUs first dose, then 108 PFUs × 4 doses] on weeks 1, 4, 6, 8, and 10 plus weekly paclitaxel (80 mg/m2) for 12 weeks, followed by doxorubicin/cyclophosphamide (60/600 mg/m2) every 2 weeks for 8 weeks. Postoperative response assessment using residual cancer burden (RCB) was performed. Primary endpoints were safety and MTD. Secondary endpoints were RCB0 rate and immune correlates. Dose-limiting toxicity (DLT) rule was grade 3-5 adverse events due to TVEC during first 5 weeks. RESULTS: Nine patients [DL 1 (n = 3); DL 2 (n = 6)] were enrolled. Six had stage II disease, and 3 had stage III (6 clinically N+). No DLTs occurred, and MTD was DL 2. Most common toxicities with TVEC were fever (n = 8), chills (n = 3), hematomas (n = 3), and injection site pain (n = 3). Thromboembolic events (n = 2) and bradycardia (n = 1) occurred during or after NAC. Five patients (55%) achieved RCB0, 2 had RCB1 (22%), and 2 had RCB2 (22%). CONCLUSIONS: The addition of TVEC to NAC was feasible at the approved dose, with manageable toxicity. The complete response rate was 55%.