Randomized phase II study of nab-paclitaxel as first-line chemotherapy in patients with HER2-negative metastatic breast cancer

Pembrolizumab plus chemotherapy for first-line treatment of advanced triple-negative breast cancer

Aim: A systematic review and network meta-analysis (NMA) was performed to evaluate the efficacy of first-line treatments for locally recurrent unresectable or metastatic triple-negative breast cancer (TNBC) patients.Materials & methods: Databases were searched for randomized controlled trials evaluating first-line treatments for locally recurrent unresectable or metastatic TNBC patients. NMA was performed to estimate relative treatment effects on overall and progression-free survival between pembrolizumab + chemotherapy and other interventions.Results: NMA including eight trials showed that the relative efficacy of pembrolizumab + chemotherapy was statistically superior to that of other immunotherapy- or chemotherapy-based treatment regimens.Conclusion: Pembrolizumab + chemotherapy confers benefits in survival outcomes versus alternative interventions for the first-line treatment of locally recurrent unresectable or metastatic TNBC patients.

Efficacy and safety of first-line treatment for metastatic triple-negative breast cancer: A network meta-analysis

Background

Metastatic triple-negative breast cancer (mTNBC) is an aggressive histological subtype with poor prognosis. Several first-line treatments are currently available for mTNBC. This study conducted a network meta-analysis to compare these first-line regimens and to determine the regimen with the best efficacy.

Methods

A systematic search of PubMed, EMBASE, the Cochrane Central Register of Controlled Bases, and minutes of major conferences was performed. Progression-free survival (PFS), overall survival (OS), and objective response rate (ORR) were analyzed via network meta-analysis using the R software (R Core Team, Vienna, Austria). The efficacy of the treatment regimens was compared using hazard ratios and 95% confidence intervals.

Results

A total of 29 randomized controlled trials involving 4607 patients were analyzed. The ranking was based on the surface under the cumulative ranking curve. Network meta-analysis results showed that cisplatin combined with nab-paclitaxel or paclitaxel was superior to docetaxel plus capecitabine in terms of PFS and ORR. For programmed death-ligand 1 (PD-L1) and breast cancer susceptibility gene (BRCA) mutation-positive tumors, atezolizumab/pembrolizumab combined with nab-paclitaxel and talazoparib was superior to docetaxel plus capecitabine. No significant difference was observed among the treatments in OS. Neutropenia, diarrhea, and fatigue were common serious adverse events.

Conclusion

Cisplatin combined with nab-paclitaxel or paclitaxel is the preferred first-line treatment for mTNBC. For PD-L1 and BRCA mutation-positive tumors, atezolizumab/pembrolizumab combined with nab-paclitaxel and talazoparib is an effective treatment option. Neutropenia, diarrhea, and fatigue are frequently occurring serious adverse events.

Progression-free survival assessment by local investigators versus blinded independent central review in randomized clinical trials in metastatic breast cancer: A systematic review and meta-analysis

INTRODUCTION

In randomized clinical trials (RCTs), blinded independent central review (BICR) is used to minimize heterogeneity and bias associated with radiological response evaluation by local investigators. However, BICR adds costs and complexity to the trial management. We assessed the discrepancy index between progression-free survival (PFS) assessment by local investigators and by BICR in RCTs conducted in patients with metastatic breast cancer (MBC).

METHODS

A systematic search of PubMed, Embase, Cochrane databases and conference proceedings (ASCO, SABCS, ESMO) was performed up to January 4, 2023 (PROSPERO: CRD42021229865). All RCTs published from 2000 to 2022, including MBC patients treated in first- or second-line, and reporting PFS assessed by local investigators and BICR were included. A discrepancy index between BICR-assessed and investigator-assessed HR was calculated for each trial and an overall combined DI was obtained using a fixed-effects model. The agreement between hazard ratios (HR) of PFS assessed by local investigators and BICR was measured using intraclass correlation coefficient (ICC).

RESULTS

We analyzed 24 studies including 13,168 patients. Among them, 19 (79%) were in first-line, 18 (75%) were phase III trials and 23 (96%) had PFS as primary endpoint. The overall combined discrepancy index was 0.97 (95%CI 0.85-1.10; ICC 0.831, p < 0.001) suggesting no statistically significant difference in PFS assessment between local investigators and BICR. This result was consistent across all analyzed subgroups.

CONCLUSIONS

The good concordance between local investigator and BICR assessments supports the reliability of local investigator-assessed PFS as primary endpoint for RCTs in MBC and questions the practical utility of implementing BICR in all RCTs.

Three-Week Versus 4-Week Schedule of nab-Paclitaxel in Patients With Metastatic Breast Cancer: A Randomized Phase II Study

BACKGROUND

This head-to-head study compared a 3-week versus 4-week schedule of nab-paclitaxel in patients with metastatic breast cancer (mBC).

METHODS

Patients with HER2-negative mBC were enrolled and randomly assigned (1:1) to receive nab-paclitaxel for a 3-week schedule (125 mg/m2 on days 1 and 8) or a 4-week schedule (same dose on days 1, 8, and 15) until disease progression or treatment intolerance. Patients with intolerable toxicities were allowed to receive a maintenance regimen after benefiting from nab-paclitaxel. The primary endpoint was progression-free survival (PFS).

RESULTS

Ninety-four patients were included in the analysis (n = 47 in each arm). A longer median PFS (mPFS) was observed in the 3-week versus the 4-week schedule in the overall population (not reached vs. 6.8 months; hazard ratio [HR] = 0.44; P = .029). Patients in the 2 arms had a similar overall survival (28.0 vs. 25.8 months), objective response rate (51.1% vs. 48.9%), and disease control rate (93.6% vs. 80.9%). The 3-week schedule was associated with a lower rate of toxicity-related treatment discontinuation (8.5% vs. 29.8%) and dose delays (6.4% vs. 23.4%).

CONCLUSION

This study demonstrated the better antitumor activity and safety profile of a 3-week over 4-week nab-paclitaxel schedule in HER2-negative mBC, suggesting that a 3-week schedule may be a better treatment regimen in clinical practice (ClinicalTrials.gov Identifier: NCT04192331).

Adverse Event Profile for Nanoparticle Albumin-Bound Paclitaxel Compared With Solvent-Based Taxanes in Solid-Organ Tumors: A Systematic Review and Meta-Analysis of Randomized Clinical Trials

BACKGROUND

Nanoparticle albumin-bound paclitaxel (nab-paclitaxel) is an innovative form of taxane that has superior antitumor effects; however, the safety profile between nab-paclitaxel and traditional taxanes remains controversial.

OBJECTIVE

To determine the burden of adverse events (AEs) in patients with multiple malignancies receiving nab-paclitaxel compared with that in patients receiving traditional taxanes.

METHODS

Randomized clinical trials comparing nab-paclitaxel with traditional taxanes (solvent-based paclitaxel [sb-paclitaxel] or docetaxel) in the treatment of primary solid-organ malignancies were included if AEs were reported as an outcome. Statistical analyses were conducted to calculate the summary odds ratio (OR) of the relevant adverse outcomes related to nab-paclitaxel and traditional taxanes. Prespecified subgroup analyses based on intervention and doses, primary tumor sites, and different ethnic groups were also performed.

RESULTS

Twelve clinical trials were included in the meta-analysis. Grade 3/4 anemia, thrombocytopenia, and neurotoxicity were more frequent with nab-paclitaxel than with traditional taxanes. Nab-paclitaxel at 100 or 125 mg/m2/w dosage was associated with fewer or similar grade 3/4 specific AEs. Allergy was less common with nab-paclitaxel. The median recovery times of neurotoxicity were 25, 64, and 37 days in patients receiving nab-paclitaxel, sb-paclitaxel, and docetaxel, respectively. Elevated incidences of specific AEs were more common in breast cancer and non-Asian patients than in other malignancies and ethnic groups, respectively.

CONCLUSION AND RELEVANCE

Nab-paclitaxel increased the risk of hematologic and non-hematologic AEs in general, but anaphylaxis was less common, and the recovery duration of neurotoxicity was shorter. Weekly administration of nab-paclitaxel at a lower dosage provided better tolerance.

Quality of life in a randomized phase II study to determine the optimal dose of 3-week cycle nab-paclitaxel in patients with metastatic breast cancer

Background

To report our findings on quality of life (QoL) in a randomized phase II study to determine the optimal dose of 3-week cycle nab-paclitaxel (q3w nab-PTX) in patients with metastatic breast cancer (MBC).

Methods

Patients with HER2-negative MBC were randomly assigned to three different doses of q3w nab-PTX (SD 260 mg/m² vs. MD: 220 mg/m² vs. LD 180 mg/m²). QoL was assessed at baseline and during the second, fourth and sixth courses of treatment using the Functional Assessment of Cancer Therapy-Taxane (FACT-Taxane), Cancer Fatigue Scale (CFS) and EuroQol 5-Dimension (EQ-5D). Comparisons were performed with mixed-model repeated measures (MMRM).

Results

A total of 141 patients were enrolled in the parent study, and 136 (96%) (44, 45 and 47 in the SD, MD, and LD groups) were included in the analysis. MMRM analysis showed that the difference from the baseline FACT-Taxane trial outcome index at MD and LD were significantly higher than that at SD (MD vs. SD P < 0.001, LD vs. SD P < 0.001). Differences from baseline for FACT-Taxane total, physical and emotional well-being, and taxane subscale scores at MD and LD were also higher than at SD. The difference from baseline for the CFS score at LD was lower than at SD (P = 0.013) and those for EQ-5D utility scores at MD and LD were higher than at SD (MD vs. SD P = 0.011, LD vs. SD P < 0.001).

Conclusion

QoL of patients treated with 220 or 180 mg/m² of q3w nab-PTX was significantly better than that of patients treated with 260 mg/m².

Trial registration

The protocol was registered at the website of the University Hospital Medical Information Network (UMIN), Japan (protocol ID: UMIN000015516), on 01/11/2014. Details are available at the following address: https://upload.umin.ac.jp/cgi-open-bin/ctr_e/ctr_view.cgi?recptno=R000017916

Supplementary Information

The online version contains supplementary material available at 10.1007/s12282-021-01290-5.

A systematic review and meta-analysis of nab-paclitaxel mono-chemotherapy for metastatic breast cancer

Background

Although various clinical trials and real-life studies have tried to explore the value of nab-paclitaxel mono-chemotherapy for metastatic breast cancer (MBC), the safety and efficacy of nab-paclitaxel remain unclear which need to be systematically evaluated.

Methods

Electronic searches for prospective clinical trials evaluating nab-paclitaxel monotherapy for MBC were performed. Requisite data were extracted, integrated and analysed from the included studies according to the different study designs using systematic review and meta-analysis. Meta-regression and subgroup analysis were further performed to explore the potential risk factors affecting each individual outcome of interest following nab-paclitaxel monotherapy.

Results

Twenty-two studies with 3287 MBC patients were included. A total of 1685 MBC patients received nab-paclitaxel as first-line therapy, 640 patients as further-line therapy, and 962 patients as mixed-line therapy. A total of 1966 MBC patients (60.40%) received nab-paclitaxel weekly, 1190 patients (36.56%) received nab-paclitaxel triweekly and 99 patients (3.04%) received nab-paclitaxel biweekly. The overall incidence rates of all-grade neutropenia, leukopenia, peripheral sensory neuropathy, and fatigue were 52% (95% CI, 38–66%, I² = 98.97%), 58% (95% CI, 43–73%, I² = 97.72%), 58% (95% CI, 48–68%, I² = 97.17%), and 49% (95% CI, 41–56%, I² = 94.39%), respectively. The overall response rate (ORR) was 40% (95% CI, 35–45%, I² = 98.97%), and the clinical benefit rate (CBR) was 66% (95% CI, 59–73%, I² = 98.97%) following nab-paclitaxel monotherapy. The median progression-free survival (PFS) was 7.64 months (95% CI, 6.89–8.40 months, I² = 92.3%), and the median overall survival (OS) was 24.51 months (95% CI, 21.25–27.78 months, I² = 92.7%). Treatment line, human epidermal growth factor receptor-2(Her-2)-negative status and dosage were found to be sources of heterogeneity among the included studies. According to the meta-regression and subgroup analysis, grade 3/4 neutropenia occurred less frequently in Her-2-negative patients than in the entire population (P = 0.046). Patients who received first-line nab-paclitaxel monotherapy showed a higher ORR (P = 0.006) and longer PFS (P = 0.045). Efficacy outcomes were not affected by the administration schedule. However, within the same schedule, patients appeared to have a superior ORR (P = 0.044) and longer PFS (P = 0.03) with an increasing dosage of nab-paclitaxel administered.

Conclusions

The benefits brought by nab-paclitaxel mono-chemotherapy in the treatment of MBC are considerable while the harm is generally manageable. Further study and validation are needed to figure out the roles which the dosage, schedule and other factors play actually in nab-paclitaxel chemotherapy.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12885-021-08441-z.

Nanoparticle albumin-bound paclitaxel versus solvent-based paclitaxel in breast cancer: A protocol for systemic review and meta-analysis

BACKGROUND

Nanoparticle albumin-bound paclitaxel (nab-PTX) has exhibited clinical efficacy in breast cancer treatment, but toxicities can be yielded more at the same time. We did this meta-analysis aiming to unambiguously compare nab-PTX with conventional solvent-based paclitaxel in breast cancer patients of all stages.

METHOD

Pubmed, EMBASE, Cochrane Library, Chinese Biomedical database, Chinese National Knowledge Infrastructure, Chinese Science and Technology Periodical database, and WangFang database were searched for head-to-head randomized controlled trials of nab-PTX and solvent-based paclitaxel in breast cancer. Other sources will also be searched like Google Scholar and gray literatures. Two researchers will independently search the database and extract data from the articles. Risk of bias will be assessed using the Cochrane Collaboration's tool. Objective tumor response rate, chemotherapy completion rate after 4 or 6 cycles, and toxicity will be primary outcomes. Disease control rate, overall survival, and progression-free survival/disease-free survival will be included in secondary outcomes. Risk ratio with 95% confidence interval was used for dichotomous variables while hazard ratio was used for time-to-event outcomes. The following 3 data sets will all be considered when synthesizing the data: intention-to-treat population, those who actually received taxanes treatment, and those who were actually assessed. All the analyses were done using Review Manager Software 5.3. Any disagreements in study selection, data collection, and analysis will be resolved by a third investigator.

RESULTS AND CONCLUSION

This study is aim to evaluate the efficacy and safety of nab-PTX compared with PTX in breast cancer treatment as well as to find the best dose or schedule and identify the benefit population. This meta-analysis could provide evidence for clinicians to make a better choice between nab-PTX and PTX in different specific contexts.

PROSPERO REGISTRATION NUMBER

CRD42019117912.

Randomized phase II study to determine the optimal dose of 3-week cycle nab-paclitaxel in patients with metastatic breast cancer

Background

Chemotherapy-induced peripheral neuropathy is commonly observed in patients treated with nanoparticle albumin–bound paclitaxel (nab-PTX). We conducted a multicenter randomized controlled study to evaluate the optimal dose of nab-PTX.

Methods

We compared three different doses of q3w nab-PTX (Standard: 260 mg/m² [SD260] vs Medium: 220 mg/m² [MD220] vs Low: 180 mg/m² [LD180]) in patients with HER2-negative metastatic breast cancer (MBC). Primary endpoint was progression-free survival (PFS). Grade 3/4 neuropathy rates in the three doses were estimated using the logistic regression model. The optimal dose was selected in two steps. Initially, if the hazard ratio (HR) for PFS was <0.75 or >1.33, the inferior dose was excluded, and we proceeded with the non-inferior dose. Then, if the estimated incidence rate of grade 3/4 neurotoxicity exceeded 10%, that dose was also excluded.

Results

One hundred forty-one patients were randomly assigned to SD260 (n = 47), MD220 (n = 46), and LD180 (n = 48) groups, and their median PFS was 6.66, 7.34, and 6.82 months, respectively. The HRs were 0.73 (95% confidence interval [CI]: 0.42–1.28) in MD220 vs SD260, 0.77 (95% CI 0.47–1.28) in LD180 vs SD260, and 0.96 (95% CI 0.56–1.66) in LD180 vs MD220. SD260 was inferior to MD220 and was excluded. The estimated incidence rate of grade 3/4 neurotoxicity was 29.5% in SD260, 14.0% in MD220, and 5.9% in LD180. The final selected dose was LD180.

Conclusions

Intravenous administration of low-dose nab-PTX at 180 mg/m² q3w may be the optimal therapy with meaningful efficacy and favorable toxicity in patients with MBC.

•

Nab-Paclitaxel at 260 mg/m² is used to treat metastatic breast cancer (MBC).

•

Nab-Paclitaxel frequently causes severe neuropathy or myalgia.

•

A reduced nab-paclitaxel dose of 180 mg/m² q3w was effective and had less toxicities.

•

Therapeutic indices of reduced doses were increased compared to the standard dose.

Macular oedema associated with taxanes: A case report and literature review

BACKGROUND AND PURPOSE

Although taxanes are a frequently used group of chemotherapy agents, they can, rarely, lead to macular oedema. The purpose of this article is to review and communicate, in an integrated way, the data of the cases previously reported in the literature, as well as to present a new case.

MATERIAL AND METHODS

Narrative review of reports of cases of macular oedema associated with taxanes, and communication of the clinical case of a 73-year-old woman who, after treatment with paclitaxel for metastatic breast cancer, developed macular oedema that disappeared after discontinuing the drug.

RESULTS

The review included 57 cases with data from 109 eyes collected in 52 articles. The large majority (76.79%) of the cases were women, and the mean age was 58.75 years. The cancer that most frequently motivated the treatment was breast cancer (60.72%), and 92.5% of cases had metastases. The most frequently associated drug was paclitaxel (52.63%). The median time to symptom development was 4.25 months. At the initial examination, 92.86% of the cases had bilateral oedema and the mean visual acuity was 0.4 (decimal scale). The mean macular thickness was 509.63 microns, and 97.83% of the eyes had no or minimal angiographic findings. In 90.57% of the cases, the treatment with taxanes was interrupted, and some other treatment was used in 43.86% of the cases, with the most widely used being acetazolamide. The outcome was favourable, to a greater or lesser extent, in 96.23% of cases.

CONCLUSIONS

Despite being a rare entity, macular oedema associated with the use of taxanes is a disorder that every oncologist and ophthalmologist should be aware of, taking into account the good outcome of the condition that usually occurs when treatment is suspended.

Efficacy and safety of nanoparticle-albumin-bound paclitaxel compared with solvent-based taxanes for metastatic breast cancer: A meta-analysis

The curative effects of nanoparticle albumin-bound (nab)-paclitaxel in the first-line treatment of metastatic breast cancer (MBC) are still controversial, with even more after the removal of marketing approval of indication of bevacizumab. Five electronic databases and the related resources were searched for eligible randomized clinical trials (RCTs) without year and language restrictions to perform a meta-analysis. The studies were comparing the efficacy and safety between nab-paclitaxel chemotherapy versus solvent-based (sb)-taxanes chemotherapy such as sb-paclitaxel and docetaxel. The primary end points were overall response rate (ORR) and disease control rate (DCR). Secondary end points were progression-free survival (PFS), overall survival (OS), adverse events (AEs), and dose discontinuation rate (DDR). Five RCTs (1,554 patients) were finally identified from 1,902 studies. When compared to sb-paclitaxel, nab-paclitaxel showed significant beneficial effects in terms of ORR (OR 2.39, 95% CI 1.69-3.37, p < 0.001), DCR (OR 1.89, 95% CI 1.07-3.35, p = 0.03), and PFS (HR 0.75, 95% CI 0.62-0.90, p = 0.002). Nab-paclitaxel also showed significantly longer OS (HR 0.73, 95% CI 0.54-0.99, p = 0.04) than docetaxel. AEs and DDR were comparable between the two arms. Using nab-paclitaxel could significantly improve efficacy with comparable toxicities in the treatment of MBC.

Subgroup analysis of Japanese patients in a Phase 3 study of atezolizumab in advanced triple-negative breast cancer (IMpassion130)

BACKGROUND

In the randomised Phase 3 IMpassion130 trial, atezolizumab combined with nab-paclitaxel (atezo + nab-P) in 902 patients with triple-negative breast cancer (TNBC) showed prolonged progression-free survival (PFS) in both the intention-to-treat (ITT) population and programmed death-ligand 1 (PD-L1)-positive subgroup compared with placebo plus nab-P (plac + nab-P). This study assessed the efficacy and safety of atezo + nab-P in the IMpassion130 Japanese subpopulation.

METHODS

Eligible patients had unresectable locally advanced or metastatic TNBC previously untreated with chemotherapy for metastatic disease. Patients were randomised 1:1 to receive either atezo + nab-P or plac + nab-P. Co-primary endpoints were investigator-assessed PFS and overall survival (ITT population and PD-L1-positive subgroup). These were also assessed in the Japanese subpopulation.

RESULTS

There were 65 Japanese patients (34 atezo + nab-P; 31 plac + nab-P). The PD-L1-positive subgroup included 25 patients (12 atezo + nab-P; 13 plac + nab-P). Median PFS was 7.4 months (atezo + nab-P) versus 4.6 months (plac + nab-P; hazard ratio [HR], 0.47; 95% CI, 0.25-0.90). In the PD-L1-positive subgroup, median PFS was 10.8 months (atezo + nab-P) versus 3.8 months (plac + nab-P; HR, 0.04; 95% CI, <0.01-0.35). Safety results in the Japanese subgroup were consistent with those in the overall population. The Japanese subgroup had a lower incidence of adverse events leading to treatment withdrawal than the overall population. More patients in the atezo + nab-P arm had neutrophil count decreases and stomatitis than patients in the plac + nab-P arm.

CONCLUSIONS

Atezo + nab-P efficacy in Japanese patients was consistent with the overall IMpassion130 population. No new safety signals were observed, and tolerability was consistent with that of the overall population.

Comparative Effectiveness of Taxane-Containing Regimens for Treatment of HER2-Negative Metastatic Breast Cancer: A Network Meta-analysis

STUDY OBJECTIVES

To compare the effectiveness of different taxane-containing regimens and to identify the best strategy for the treatment of human epidermal growth factor receptor 2 (HER2)-negative metastatic breast cancer (MBC).

DESIGN

Network meta-analysis of 20 randomized controlled trials (RCTs).

PATIENTS

A total of 6577 patients with HER2-negative MBC who received treatment (20 different regimens) with taxanes (paclitaxel [4267 patients] or docetaxel [2310 patients]).

MEASUREMENTS AND MAIN RESULTS

The PubMed, Embase, Cochrane Library, and ClinicalTrials.gov databases were searched (through March 2019) for RCTs that evaluated any taxane-containing regimens for the treatment of HER2-negative MBC. A network meta-analysis in a Bayesian framework was performed using the random-effects model. We compared the surface under the cumulative ranking (SUCRA) curve for each regimen. Overall, paclitaxel-based combinations were superior to paclitaxel alone in objective response rate (ORR) (odds ratio 1.60, 95% credible interval [CrI] 1.15-2.16) and overall survival (OS) (hazard ratio 1.08, 95% CrI 1.01-1.15). Docetaxel-based combinations were also superior to paclitaxel alone in ORR. Among the paclitaxel-based regimens, based on the results of SUCRA, paclitaxel + bevacizumab + capecitabine was likely to be the most efficacious in improving ORR, OS, and progression-free survival (PFS), whereas paclitaxel + gemcitabine was likely to be the most efficacious in 1-year OS rate. Among the docetaxel-based regimens, based on the results of SUCRA, docetaxel + gemcitabine was likely to be the most efficacious in improving PFS and OS.

CONCLUSION

These findings demonstrated that paclitaxel-based combinations can provide significant improvement in ORR and OS compared with paclitaxel alone. The regimens of paclitaxel + bevacizumab + capecitabine, docetaxel + gemcitabine, and paclitaxel + gemcitabine may be superior to other regimens for the treatment of HER2-negative MBC.

Preliminary safety and efficacy of first-line pertuzumab combined with trastuzumab and taxane therapy for HER2-positive locally recurrent or metastatic breast cancer (PERUSE)

BACKGROUND

Pertuzumab combined with trastuzumab and docetaxel is the standard first-line therapy for HER2-positive metastatic breast cancer, based on results from the phase III CLEOPATRA trial. PERUSE was designed to assess the safety and efficacy of investigator-selected taxane with pertuzumab and trastuzumab in this setting.

PATIENTS AND METHODS

In the ongoing multicentre single-arm phase IIIb PERUSE study, patients with inoperable HER2-positive advanced breast cancer (locally recurrent/metastatic) (LR/MBC) and no prior systemic therapy for LR/MBC (except endocrine therapy) received docetaxel, paclitaxel or nab-paclitaxel with trastuzumab [8 mg/kg loading dose, then 6 mg/kg every 3 weeks (q3w)] and pertuzumab (840 mg loading dose, then 420 mg q3w) until disease progression or unacceptable toxicity. The primary end point was safety. Secondary end points included overall response rate (ORR) and progression-free survival (PFS).

RESULTS

Overall, 1436 patients received at least one treatment dose (initially docetaxel in 775 patients, paclitaxel in 589, nab-paclitaxel in 65; 7 discontinued before starting taxane). Median age was 54 years; 29% had received prior trastuzumab. Median treatment duration was 16 months for pertuzumab and trastuzumab and 4 months for taxane. Compared with docetaxel-containing therapy, paclitaxel-containing therapy was associated with more neuropathy (all-grade peripheral neuropathy 31% versus 16%) but less febrile neutropenia (1% versus 11%) and mucositis (14% versus 25%). At this preliminary analysis (52 months' median follow-up), median PFS was 20.6 [95% confidence interval (CI) 18.9-22.7] months overall (19.6, 23.0 and 18.1 months with docetaxel, paclitaxel and nab-paclitaxel, respectively). ORR was 80% (95% CI 78%-82%) overall (docetaxel 79%, paclitaxel 83%, nab-paclitaxel 77%).

CONCLUSIONS

Preliminary findings from PERUSE suggest that the safety and efficacy of first-line pertuzumab, trastuzumab and taxane for HER2-positive LR/MBC are consistent with results from CLEOPATRA. Paclitaxel appears to be a valid alternative taxane backbone to docetaxel, offering similar PFS and ORR with a predictable safety profile.

CLINICALTRIALS.GOV

NCT01572038.

Randomized phase II study of nab-paclitaxel as first-line chemotherapy in patients with HER2-negative metastatic breast cancer

Weekly administration of nanoparticle albumin-bound paclitaxel (nab-paclitaxel) has been shown to be a safe and effective treatment for metastatic breast cancer (MBC) in clinical studies. We conducted a multicenter, randomized, open-label phase II study to compare the efficacy and safety of weekly nab-paclitaxel and docetaxel in Japanese patients with human epidermal growth factor receptor 2-negative MBC. The primary endpoint was progression-free survival (PFS). Patients were randomized to receive nab-paclitaxel (150 mg/m² nab-paclitaxel once per week for 3 of 4 weeks; n = 100) or docetaxel (75 mg/m² docetaxel every 3 weeks; n = 100). The median PFS by independent radiologist assessment was 9.8 months (90% confidence interval [CI]: 8.5-11.2) for nab-paclitaxel and 11.2 months (90% CI: 8.4-13.8) for docetaxel (hazard ratio: 1.25, P = 0.363), and the median overall survival was 42.4 months and 34.0 months, respectively. The overall response rate was 56.1% for nab-paclitaxel and 52.5% for docetaxel. Adverse events in both treatment arms were similar to previous reports. Neutropenia was the most common adverse event in both arms, with 35.0% of patients in the nab-paclitaxel arm and 89.0% in the docetaxel arm experiencing grade 4 neutropenia. Grade 3 peripheral sensory neuropathy occurred in 22.0% of patients in the nab-paclitaxel and 5.0% in the docetaxel arm. In this study, although weekly nab-paclitaxel 150 mg/m² did not show superiority in PFS compared with docetaxel, efficacy outcomes were similar in patients treated with weekly nab-paclitaxel and docetaxel.