9532 Background: Chemotherapy induced peripheral neuropathy (CIPN) continues to be a substantial problem for many cancer patients (pts). Pursuant to promising appearing pilot data, the current study evaluated the use of vitamin E for the prevention of CIPN. Methods: A phase III, randomized, double-blind, placebo controlled study was conducted in pts undergoing therapy with neurotoxic chemotherapy, utilizing twice daily dosing of vitamin E (400mg)/placebo. The primary endpoint was the incidence of grade 2+ sensory neuropathy (SN) toxicity (CTCAE v 3.0) in each treatment arm, analyzed by Chi-square testing. Major eligibility criteria included: planned curative intent adjuvant chemotherapy with neurotoxic chemotherapy, ≥ 18 years of age, ECOG PS of ≤2, no existing peripheral neuropathy or coronary artery disease, no prior treatment with neurotoxic chemotherapy, and no concurrent treatment with neuropathic or opioid pain medication. Planned sample size was 100 patients per arm, to provide 80% power to detect a difference in incidence of grade 2+ SN toxicity from 25% in the placebo group to 10% in the vitamin E group. Results: Two-hundred seven pts were enrolled between 12/01/2006 and 12/14/2007. Cytotoxic agents included taxanes (109), cisplatin (8), carboplatin (2), oxaliplatin (50) or combination (20). Eleven pts canceled prior to starting treatment and there were 7 ineligible pts on study. Thus there were 189 evaluable pts included in the current analysis. In this analysis, there was no difference in the incidence of grade 2+ SN between the 2 arms (vitamin E- 34% [95% CI- 25.0–44.8%] placebo- 29% [20.1–39.4%]; P=0.43). There, likewise, were no significant differences between treatment arms for time to onset of neuropathy (P= 0.72), for chemotherapy dose reductions due to neuropathy (P= 0.21) or patient questionnaire reported neuropathy symptoms. The treatment was well tolerated overall. Conclusions: Vitamin E did not appear to reduce the incidence of sensory neuropathy in the studied group of patients receiving neurotoxic chemotherapy but it appeared to be well tolerated. No significant financial relationships to disclose.
Randomized phase III trial of eribulin (E) versus standard weekly paclitaxel (P) as first- or second-line therapy for locally recurrent or metastatic breast cancer (MBC).
Journal of Clinical Oncology | May 25, 2020 | Volume: 38 | Issue: 15_suppl | Pages: 1016-1016
1016 Background: The ph III EMBRACE trial of E vs physician’s choice of tx led to FDA approval of E as ≥3rd-line tx for MBC pts with prior exposure to anthracyclines/taxanes. The ph III BOLD 301 trial of E vs capecitabine in advanced BC treated with anthracyclines/taxanes showed a nonsignificant trend to improved median OS for all pts; pre-planned analysis by HER2 status revealed a nominally significant benefit for HER2- pts. Methods: RU011201I is an investigator initiated ph III trial with 1:1 randomization to E (1.4 mg/m2 D1,8 q21days) vs P (90 mg/m2 D1,8,15 q28days) within strata defined by (neo)adjuvant taxanes (yes/no), HR status (+/-), and line of tx (1st/2nd). Pts had measurable or non-measurable disease by RECIST v1.1; new or progressive mets; peripheral neuropathy (PN) gr<2; ≤1 prior chemotx regimens for advanced or MBC. Asymptomatic brain mets with stable MRIs for >3 mos were allowed. (Neo)adjuvant taxanes were allowed if >12 mos between tx completion and disease recurrence. Radiographic studies occur q12wks. Survival data are collected q12wks after the Off-Tx Visit. Pts reported side effects weekly; post-baseline symptomatic AE rates worse than baseline were compared between arms using Fisher’s exact tests. We report clinical outcomes and the primary objective related to PRO-CTCAE use. Results: 201 pts enrolled 3/2014 - 5/2018 with 33.8 mos median f/u; 3 are on tx as of 2/20/20 (1E, 2P). Pt characteristics were the same between E vs P: median age 62 yrs (range 27-85); 42% prior taxane; 78% ER+; 70% starting 1st line tx. Baseline lesion distribution was similar except for lung mets (37E, 53P). No difference was seen between E vs P in PFS (5.7 vs 5.9 mos; P=0.72), OS (18.1 vs 16.4 mos; P=0.75), TTF (5.3 vs 4.9 mos; P=0.82), DOR (10.8 vs 12.3 mos; P=0.84), or number of metastatic events (55 vs 54). 37E and 36P pts required ≥1 dose reduction. Hematologic toxicities ≥ gr 3 were higher with E (40 vs 22%). PN events were similar: 56 vs 58 total, 4 vs 7 motor, 52 vs 51 sensory. Median duration of PN and median time to 1st PN event were 74 vs 140 and 56 vs 41 days. Worsened numbness/tingling severity and other pt-reported AE rates were similar, but worsened numbness/tingling interference (63% vs 78%, P=0.04) and vomiting frequency (35% vs 57%, P=0.005) were lower with E. Conclusions: Clinical outcomes were equivalent with E vs P as 1st/2nd line tx for HER2- advanced BC. The nature and severity of PN were similar between arms, but time of onset, duration, and interference with daily living favor E. E may be a suitable treatment option in this setting. Clinical trial information: NCT02037529 .
Anti-Tumor Activity of Single-Agent CCI-779 for Relapsed Mantle Cell Lymphoma: A Phase II Trial in the North Central Cancer Treatment Group.
Abstract Purpose: Mantle cell lymphoma (MCL) is characterized by a t(11;14) resulting in overexpression of cyclin D1, a member of the phosphatidylinosital 3 kinase (PI3K) pathway. This study tested whether CCI-779, which inhibits the PI3K pathway at the level of the mammalian target of rapamycin (mTOR) could produce tumor responses in patients (pts) with MCL. Patients and Methods: Eligible pts had biopsy-proven, cyclin D1 positive MCL and had relapsed or were refractory to therapy. Pts received CCI-779 250 mg IV every week as a single agent. Pts were re-staged after 1 cycle (4 doses) and every 3 cycles thereafter. Pts with a tumor response after 6 cycles were eligible to continue drug for a total of 12 cycles or 2 cycles after complete remission (CR) and then were observed. Results: Thirty-five pts were enrolled and evaluable for toxicity; 1 patient had MCL by histology but was cyclin D1 negative and ineligible for efficacy evaluation. The median age was 70 years (range, 38–89), 91% were stage 4, and 69% had ≥ 2 extranodal sites. Pts had received a median of 3 prior therapies (range, 1–11) and 54% were refractory to their last treatment. The overall response rate was 38% (13/34) with 1 CR (3%) and 12 PRs (35%), surpassing the pre-defined criteria for a promising agent. Responses tended to occur rapidly with median time to response of 1 month (range, 1–8). To date, 26 patients have progressed, with a median time-to-progression of 6.8 months (95% CI: 3.8 – 9.7). Median duration of response for the 13 responders was 5.7 months (95% CI: 5.2 – 13.2). Overall, 32 out of 35 patients who received treatment had grade 3 or 4 toxicity. The most common toxicities were hematologic with grade 3 (n=24) or grade 4 (n=4). Thrombocytopenia was the most frequent grade 3/4 toxicity (n=25) and the largest cause of dose-reductions, although counts typically recovered within one week. Only 4 patients could tolerate sustained 250 mg per week throughout their treatment (including one who went on to alternate treatment after 1 cycle) and the median dose/month was 175 mg. Conclusions: Single-agent CCI-779 has substantial anti-tumor activity in relapsed MCL. This study demonstrates that agents, which selectively target cellular pathways dysregulated in MCL cells can produce therapeutic benefit. The high response rate warrants further studies of this agent in MCL, but the high incidence of hematologic toxicity suggests that a lower dose should be explored. CCI-779 at 25mg is currently being evaluated in MCL through an NCCTG trial
N0937(Alliance): Final clinical results and correlative data from the phase II trial of cisplatin (C) and the novel agent brostallicin (B) in patients with metastatic triple-negative breast cancer (mTNBC).
Journal of Clinical Oncology | March 11, 2020 | Volume: 31 | Issue: 15_suppl | Pages: 1059-1059
1059 Background: Relapsed TNBC is characterized by its poor prognosis. B is a synthetic DNA minor groove binding non-cross resistant agent that is fully active against DNA-mismatch repair deficient tumor cells. C increases GSH/GST in which enhances the efficacy of B. Methods: Phase II study in pts with mTNBC. C Day 1 followed by B Day 2, repeated every 21 days. Aim: Efficacy of C + B in mTNBC. Primary endpoint: PFS at 3 mo. Secondary endpoints include ORR, duration of response (DOR), 6-mo PFS, OS and AE profile. Tertiary endpoints include assessment of baseline GSH levels, prevalence of BCRA1 mutation and pERK, and correlations with outcome. Results: Closed 3/2012. 48 pts accrued (1 ineligible pt). Median f/u 11.4 mo (6.6-14.8); 2 pts still on treatment. 47 pts evaluable for the PFS endpoint and AEs. 49% received therapy as 3rd-5th line. Median number of cycles = 4 (range 1-15). There are currently 9 confirmed responses (8 PR and 1 CR); DOR = 2.6-14.5 mo. The 3-mo PFS = 51%; 6-mo PFS = 28%; the median TTP is 3.2 mo. AE data: 75% G3/4 hematologic AE: febrile neutropenia 19%. Non-hematologic AEs included G3 (47%) and G4 (15%): G3 fatigue 17%; and no G5 non-heme AE. No correlation of GSH/GST levels with outcome was found. Among 35 pts with evaluable data, no association between BRCA1 expression and outcomes was found. pERK expression was negatively associated with 3-mo PFS, but not 6-mo PFS. Cytoplasmic pERK expression was negatively associated with tumor response (p=0.03). No significant effect of BRCA-1 or pERK expression was found on OS. Conclusions: This trial showed B + C is an active regimen, especially in heavily pretreated mTNBC pts. Correlative data demonstrated a negative association between pERK expression and outcomes. A randomized phase II trial is in development. Clinical trial information: NCT01091454.
N0321: A phase II study of bortezomib, paclitaxel, carboplatin (CBCDA), and radiotherapy (RT) for locally advanced non-small cell lung cancer (NSCLC).
Journal of Clinical Oncology | March 11, 2020 | Volume: 30 | Issue: 15_suppl | Pages: 7073-7073
7073 Background: In preclinical studies, combinations of bortezomib and RT result in synergistic tumor killing (Cancer Chemother Pharmacol. 2007;59:207-15). Our group reported the results from the phase I portion of this study previously (J Clin Oncol. 200;28 (suppl; abstr 7085)). Based on these data, we undertook a phase II study of bortezomib in combination with paclitaxel/CBCDA and RT. Methods: Based on results from our previously reported phase I trial, systemic therapy included bortezomib (1.2 mg/m² IV days 1,4,8,11), paclitaxel (175 mg/m² IV day 2), and carboplatin (CBCDA; AUC=6 day 2) given every 3 weeks for 2 cycles. Thoracic radiotherapy (RT) included 60Gy/30 daily fractions starting day 1. The primary endpoint was the 12-month survival rate. If 41 or more of these 60 patients (68%) were alive at least 12 months after study entry, the trial would be deemed as positive and further study would be warranted. Results: 27 pts were enrolled to the phase II portion: M/F=17/10; stage IIIA/IIIB=13/14; ECOG PS 0/1=9/18; and median age: 58 (range 43-79). 18 pts (67%) completed therapy per protocol. At a planned interim analysis, 23 of 26 evaluable patients (88.5%, 95% CI: 70-98%) survived for at least 6 months, which exceeded the boundary of 21 or more needed to continue to full accrual. This trial could have continued per protocol, but was closed early due to slow accrual. With a median follow-up of 15.0 months in the 17 patients still alive, the 12-month survival rate was 71% (95% CI: 49 – 85). The median OS was 19 months (95% CI: 11 – no upper). Grade 3 or higher adverse events (regardless of attribution) were reported in 22 (82%) patients. Grade 4/5 adverse events were reported in 15 (56%) patients. There was one grade 5 event (pneumonitis). The most common (5 or more patients) grade 3/4 adverse events were fatigue (22%), leukopenia (63%), neutropenia (67%), and thrombocytopenia (44%). Conclusions: The addition of bortezomib resulted in high levels of severe hematologic toxicity, but also demonstrated evidence of activity with a 12-month survival rate of 71% and a median OS of 19 months. Further testing of this regimen in a larger study appears warranted.
BAY 43–9006 as single oral agent in patients with metastatic breast cancer previously exposed to anthracycline and/or taxane
Journal of Clinical Oncology | March 9, 2020 | Volume: 24 | Issue: 18_suppl | Pages: 577-577
577 Background: BAY 43–9006 targets the ras/raf signaling pathway and inhibits VEGFR-2, VEGFR-3 and or PDGFR-β growth factors. A study was conducted to assess anti-tumor activity and the toxicity profile in patients (pts) with metastatic breast cancer (MBC). Methods: A two-stage phase II study was conducted with pts with MBC who had measurable disease and were candidates for 1 st or 2 nd line chemotherapy and had previously received an anthracycline and/or a taxane in the neoadjuvant, adjuvant, or metastatic setting. Pts started with a dose of 400 mg twice daily on days 1–28 of each 4 week cycle. Based on interval adverse events (AEs), a dose reduction was considered as 400 mg given one time daily. Primary endpoint was tumor response defined as a complete or partial response (PR) according to RESIST. The study required 40 pts, but was to be terminated if 0 or 1 responses occurred among 1 st 20 eligible pts. Results: 23 pts enrolled with a median age of 54 (range 37–70) but 3 were declared ineligible. All 23 pts were included in all analyses except efficacy analysis as stated per protocol. Fifteen (65%) had visceral metastasis; 22 (96%) had prior anthracycline treatment (tx); 16 (70%) had prior taxane tx.; 10 (44%) had received prior chemotherapy for metastatic disease and 14 (61%) had a prior relapse free interval of 12 months (mos) or more. Pts received tx for a median of 2 cycles (range 1–8) with a median follow-up of 7.2 mos. Dose reductions were due to dermatitis/skin rash (3), hand/foot skin reaction (2), hypertension (1) and cramping hands/feet (1). No grade 4 AEs occurred and grade 3 AEs included acne (2), hand/foot skin reaction (1), neutropenia (1), cough (1), wound infection (1), and prolonged PTT (1). Among the 20 pts eligible for efficacy analysis one pt (5%; 95% CI 0.5–20.5%) achieved a PR with duration of 3.6 mos and one pt achieved stable disease for at least 6 mos. The 6-month overall survival rate was 81% and the progression-free survival rates were 53% at 2 mos, 24% at 4 mos and 6% at 6 mos. Median time to progression was 2 mos. Based on the lack of sufficient response, we did not proceed with the 2nd stage of this study. Conclusion: Treatment with oral BAY 43–9006, while well tolerated, does not have sufficient activity to warrant further testing as a single agent in this disease setting. Author Disclosure Employment or Leadership Consultant or Advisory Role Stock Ownership Honoraria Research Funding Expert Testimony Other Remuneration Genentech Genentech
A front-line window of opportunity phase II study of sorafenib in patients with advanced non-small cell lung cancer: A North Central Cancer Treatment Group study
Journal of Clinical Oncology | March 6, 2020 | Volume: 25 | Issue: 18_suppl | Pages: 7547-7547
7547 Background: Sorafenib is a multikinase inhibitor with single-agent activity in previously treated NSCLC. In an effort to evaluate its single agent activity in previously untreated NSCLC, the NCCTG undertook a front-line “window of opportunity” study. Materials and Methods: Patients with stage IIIB (pleural effusion) or stage IV NSCLC received sorafenib dosed at 400 mg BID continuously, with a cycle defined as 4 weeks. Patients were evaluated weekly during the first 2 cycles with those who progressed rapidly going on to receive standard chemotherapy. Based on a two-stage Fleming design, if only at most 1 confirmed response was observed in the first 20 patients enrolled to stage I, the regimen would be considered ineffective. If 2 or more responses were observed, the study would proceed to stage 2 and accrue an additional 22 patients. If 5 or more confirmed responses were observed, the regimen would be recommended for further testing. Results: The study did not meet the stage I efficacy criteria (only 1 confirmed partial response in the first 20 patients) and was permanently closed after enrolling 25 evaluable patients [15 females, 10 males; 4 stage IIIB, 21 stage IV; median age 67 (45–85)]. 2 patients are still receiving treatment (14 and 15 months). No grade 3 or higher hematologic adverse events were observed. Thirteen (52%) patients had a grade 3 non-hematologic adverse event with fatigue (20%), diarrhea (8%), and dyspnea (8%) being the most common. There was one grade 4 pulmonary hemorrhage. A total of 3 (12%) PRs; and 7 (28%) SD were observed in the 25 patients 7 (28%) patients were progression- free at 24 weeks. Median survival and median time to progression were 8.8 and 2.9 months respectively. Conclusion: While the pre- specified efficacy endpoints were not met, the objective response rate of 12% and median survival of 8.8 months suggest that single agent sorafenib has activity similar to two-drug combinations. The feasibility and utility of the “window of opportunity” design in estimating the activity of novel compounds was demonstrated. Finally, the single-agent activity of sorafenib argues for combination studies with standard chemotherapy agents. No significant financial relationships to disclose.
Oxybutynin vs Placebo for Hot Flashes in Women With or Without Breast Cancer: A Randomized, Double-Blind Clinical Trial (ACCRU SC-1603)
JNCI Cancer Spectrum | October 18, 2019 | Volume: 4 | Issue: 1 | Pages: No page available
Abstract Background Hot flashes (HFs) negatively affect quality of life among perimenopausal and postmenopausal women. This study investigated the efficacy of oxybutynin vs placebo in decreasing HFs. Methods In this randomized, multicenter, double-blind study, women with and without breast cancer with 28 or more HFs per week, lasting longer than 30 days, who were not candidates for estrogen-based therapy, were assigned to oral oxybutynin (2.5 mg twice a day or 5 mg twice a day) or placebo for 6 weeks. The primary endpoint was the intrapatient change from baseline in weekly HF score between each oxybutynin dose and placebo using a repeated-measures mixed model. Secondary endpoints included changes in weekly HF frequency, HF-related daily interference scale questionnaires, and self-reported symptoms. Results We enrolled 150 women. Baseline characteristics were well balanced. Mean (SD) age was 57 (8.2) years. Two-thirds (65%) were taking tamoxifen or an aromatase inhibitor. Patients on both oxybutynin doses reported greater reductions in the weekly HF score (5 mg twice a day: −16.9 [SD 15.6], 2.5 mg twice a day: −10.6 [SD 7.7]), placebo −5.7 (SD 10.2); P < .005 for both oxybutynin doses vs placebo), HF frequency (5 mg twice a day: −7.5 [SD 6.6], 2.5 mg twice a day: −4.8 [SD 3.2], placebo: −2.6 [SD 4.3]; P < .003 for both oxybutynin doses vs placebo), and improvement in most HF-related daily interference scale measures and in overall quality of life. Patients on both oxybutynin arms reported more side effects than patients on placebo, particularly dry mouth, difficulty urinating, and abdominal pain. Most side effects were grade 1 or 2. There were no differences in study discontinuation because of adverse effects. Conclusion Oxybutynin is an effective and relatively well-tolerated treatment option for women with HFs.
A Phase III, Randomized Study of the Effects of Parenteral Iron, Oral Iron, or No Iron Supplementation On the Erythropoietic Response to Darbepoetin Alfa for Patients with Chemotherapy-Associated Anemia: A Study of the Mayo Clinic Cancer Research Consortiu
Abstract Abstract 630 Introduction: Erythropoiesis stimulating agents (ESAs) improve hemoglobin (Hb) levels and reduce red blood cell (RBC) transfusion requirements in patients (pts) with chemotherapy-associated anemia (CAA), but many pts with CAA do not respond to ESAs. Functional iron deficiency due to inflammation-related hepcidin production and pathological sequestration of bioavailable iron may be an important reason for lack of ESA response in iron-replete pts. The common clinical practice of co-administering oral iron with ESAs does not appear to alter the disordered iron processing in CAA. We conducted a prospective trial to evaluate whether parenteral iron might overcome functional iron deficiency and benefit iron-replete pts with CAA undergoing ESA treatment. Patients and Methods: Eligible pts were receiving chemotherapy for a non-myeloid neoplasm and had Hb level <11.0 g/dL, ferritin >20 ng/mL, transferrin saturation <60%, and ECOG performance score ≤2. All pts received darbepoetin alfa (DA) 500 mcg subcutaneously q3wks until Hb reached >11 g/dL, and thereafter DA 300 mcg q3wks; DA was held for Hb >13 g/dL until Hb fell to <12 g/dL, then restarted with 25% dose reduction. Pts were randomized 1:1:1 to receive either sodium ferric gluconate complex in sucrose (Ferrlecit) 187.5 mg intravenously q3wks (total dose 1,125 mg), oral ferrous sulfate 325 mg once daily, or oral placebo. Quality of life (QOL) was measured using the Symptom Distress Scale, Brief Fatigue Inventory, FACT-An, and LASA instruments. The primary endpoint was the proportion of patients achieving Hb ≥12.0 g/dL or ≥2.0 g/dL Hb increment from baseline by the end of the 16-week study. Secondary endpoints included transfusion requirements. changes in QOL, changes in iron parameters, and adverse events (AEs). Results: Planned enrollment was 582 pts, but the study met an early stopping rule due to an excess of serious AEs in the IV iron arm; 502 pts enrolled at 14 MCCRC sites between February 2006 and December 2008. The median age of the 490 evaluable pts was 64 years; 65% were female and 94% white; 6% had hematological neoplasms (lymphoma or multiple myeloma), 25% had severe anemia (Hb <9.5 g/dL), 48% received platinum-containing therapy, and 66% completed all 16 weeks of the study. Baseline characteristics were comparable between groups. With respect to the primary endpoint, 69.5% of IV iron-treated pts achieved a Hb response (median Hb increase from baseline to end of study, 2.7 g/dl), compared to 66.9% with oral iron (median increase, 2.4 g/dL) and 65.0% with placebo (median increase 2.3 g/dl) (p=0.73). There were no significant differences in the proportion of patients requiring RBC transfusion (12.8% for IV iron, 12.9% for oral iron, 13.5% for placebo; p=0.87) or QOL changes. A total of 17 pts (3%) died on study–8 in the IV iron arm, 6 oral iron, 3 placebo (p=0.22). Grade 3 or higher AEs occurred in 54% of IV iron pts compared to 43% for oral iron and 45% placebo (p=0.03). The end-of-study ferritin level was higher in the IV iron arm (median 501 ng/mL) compared to the oral iron (229 ng/mL) and placebo (193 ng/mL) arms (p=0.0022). The median total DA dose administered was similar between arms (p=0.71). Conclusions: Co-administration of DA with intravenous ferrous gluconate q3wks did not result in improvement in Hb levels, reduce transfusions, improve QOL endpoints, or allow lower doses of DA, compared with DA + oral iron or DA + placebo. IV iron increased AEs. The reason for discordant results with 5 previous smaller studies is unclear. Disclosure: The study was supported by a grant from Amgen (Thousand Oaks, CA) to the MCCRC. Disclosures: Off Label Use: Ferrlecit, chemotherapy-associated anemia.
Phase II Trial of Eribulin in Patients With Metastatic Hormone Refractory Prostate Cancer
American Journal of Clinical Oncology | February 21, 2019 | Volume: 42 | Issue: 4 | Pages: 375-381
Background: Eribulin mesylate, a synthetic analog of halichondrin B, is a novel tubulin-binding agent that inhibits cancer cell proliferation at low-nanomolar levels. Methods: In a multicenter ECOG trial, patients with progressive metastatic CRPC, ECOG 0-2 were treated with eribulin 1.4 mg/m2 as an IV bolus over 5 minutes on days 1 and 8 of a 21-day cycle. This noncomparative study stratified points to either a chemonaive (CN), prior-taxane (Tax) only, or 2 prior cytotoxic (TCx) chemotherapy arm. The trial was powered to detect a 50% PSA reduction using Consensus Criteria in at least 40% versus 20% (90% power, one-sided α=0.10) for the CN stratum and 25% versus. 10% (power 87%, one-sided α=0.10) for the Tax and TCx strata. Results: In total, 119 pts received treatment of which 116 were eligible for the primary response determination in this study. Median age 70 years (range, 45 to 88); median number of treatment cycles 4 (range, 1 to 20+); ECOG 0-1 90%. Confirmed PSA response rates (50% decline from baseline) were 29% (90% [18.2%, 41.2%]; P=0.20), 10% (90% [5.2%, 27.1%]; P=1.00), and 4% ([0.2%, 18.3%]; P=0.59) in the chemonaive stratum, the prior-taxane stratum, and the 2-prior-chemotherapy stratum, respectively. Median progression-free survival was 3.5 months (95% CI, 2.0, 5.9), 2.3 months (95% CI, 2.0, 2.9) and 3.7 months (95% CI, 2.1, 4.2) for the chemonaive stratum, the prior-taxane stratum and the 2-prior-chemotherapy stratum, respectively. Nonhematological toxicities of any grade (mainly grade 1 and 2) were fatigue (74%), neuropathy (40%), alopecia (39%), nausea (35%), and anorexia (34%). Common hematological toxicities were decreased leukocytes (75%), decreased neutrophils (72%), and decreased hemoglobin (66%). The most common grade ≥ 3 toxicities were decreased neutrophils (55%), decreased leukocytes (42%), sensory neuropathy (13%), and fatigue (11%). Overall, there was a 4% rate of febrile neutropenia. Conclusions: In summary, per the prespecified study endpoints, eribulin did not have adequate activity in chemotherapy naïve or chemotherapy pretreated patients with metastatic CRPC to support further study in this setting.