Randomized Phase II Trial of weekly paclitaxel alone versus trastuzumab plus weekly paclitaxel as first-line therapy of patients with Her-2 positive advanced breast cancer

Updated efficacy and safety of HLX02 versus reference trastuzumab in metastatic HER2-positive breast cancer: A randomized phase III equivalence trial

AIM

Equivalence between HLX02 and trastuzumab sourced from the European Union (EU-trastuzumab), in combination with docetaxel, was demonstrated in a phase III study. This study aimed to evaluate the long-term efficacy and safety data after 3 years of follow-up.

METHODS

Patients with previously untreated, HER2-positive metastatic breast cancer received intravenous HLX02 or EU-trastuzumab (initial dose of 8 mg/kg, followed by 6 mg/kg every 3 weeks for up to 12 months) in combination with docetaxel. Primary endpoint was the overall response rate up to week 24 (ORR24). Secondary endpoints including updated overall survival (OS), progression-free survival (PFS), safety and immunogenicity are reported in this long-term follow-up analysis.

RESULTS

After a median follow-up duration of 35.0 months, 270 out of the 649 enrolled patients had died; 128 (39.5 %) in the HLX02 and 142 (43.7 %) in the EU-trastuzumab group. Median OS was 37.3 (95 % CI 36.2, not evaluable [NE]) months and not reached (95 % CI 34.2, NE) (stratified HR 0.86 [95 % CI 0.68, 1.10]; p = 0.229), with a 3-year OS rate of 57.5 % and 54.0 %, respectively. Median PFS at this long-term follow-up assessment was 11.7 (95 % CI 11.5, 12.1) months for the HLX02 group and 10.6 (95 % CI 9.5, 11.7) months for the EU-trastuzumab group (stratified HR 0.86 [95 % CI 0.69, 1.06]; p = 0.158). No new safety concerns were reported until the end of the survival follow-up.

CONCLUSION

Long-term efficacy and safety were consistent with the previous findings. No clinically meaningful differences between HLX02 and reference trastuzumab were demonstrated.

CLINICAL TRIAL REGISTRATION

Chinadrugtrials.org CTR20160526 (September 12, 2016), ClinicalTrials.gov NCT03084237 (March 20, 2017), EudraCT 2016-000206-10 (April 27, 2017).

QL1701 (a proposed trastuzumab biosimilar) versus reference trastuzumab plus docetaxel as first-line therapy for HER2-positive metastatic breast cancer: a multicenter, randomized, double-blinded, parallel-controlled, phase III equivalence trial

BACKGROUND

QL1701 is a proposed biosimilar to the reference trastuzumab (Herceptin®). This trial compared the efficacy and safety of QL1701 with the reference trastuzumab in first-line treatment of human epidermal growth factor receptor 2 (HER2)-positive metastatic breast cancer.

MATERIALS AND METHODS

This randomized, double-blinded, parallel-controlled, phase III equivalence trial was conducted in 73 centers in China. Eligible patients with histologically or cytologically diagnosed HER2-positive metastatic breast cancer were randomly assigned (1 : 1) to receive either QL1701 or reference trastuzumab in combination with docetaxel (every 3 weeks) for eight cycles as the first-line treatment. Then, in patients with objective responses or stable disease, the QL1701 or reference trastuzumab with or without docetaxel was maintained for totally up to 12 months if tolerated. The primary endpoint was 24-week objective response rate (ORR) assessed by an independent review committee (IRC). The equivalence margin was 0.80-1.25 with a 90% confidence interval (CI) for the ORR ratio (QL1701 to reference trastuzumab).

RESULTS

Between 29 April 2020 and 15 March 2022, 474 patients were randomized, and 473 received either QL1701 (n = 236) or reference trastuzumab (n = 237). The risk ratio for 24-week ORR was 1.07 (90% CI 0.94-1.21). The 90% CI fell within the pre-specified equivalence margin of 0.80-1.25. The 24-week ORR assessed by IRC was 59.7% (95% CI 53.2% to 66.1%) versus 56.1% (95% CI 49.5% to 62.5%) in QL1701 and the reference trastuzumab, respectively. As of 12 April 2023, there were no notable differences in progression-free survival (median: 8.3 versus 8.4 months) and overall survival (1-year rate: 95.1% versus 93.3%) between the two groups. Safety, pharmacokinetic (PK), and immunogenicity profiles were similar between the two groups.

CONCLUSION

QL1701 demonstrated equivalent efficacy and similar safety to the reference trastuzumab when combined with docetaxel in the first-line treatment of patients with HER2-positive metastatic breast cancer, with similar PK and immunogenicity profiles.

Paclitaxel therapeutic drug monitoring - International association of therapeutic drug monitoring and clinical toxicology recommendations

Paclitaxel, one of the most frequently used anticancer drugs, is dosed by body surface area, which leads to substantial inter-individual variability in systemic drug exposure. We evaluated clinical evidence regarding the scientific rationale and clinical benefit of individualized paclitaxel dosing based on measured systemic concentrations, known as therapeutic drug monitoring (TDM). In retrospective studies, higher systemic exposure is associated with greater toxicity and efficacy of paclitaxel treatment across several disease types and dosing regimens. In prospective trials, TDM reduces variability in systemic exposure, and has been demonstrated to reduce toxicity while retaining treatment efficacy for 3-weekly dosing in patients with advanced non-small cell lung cancer. Despite the demonstrated benefits of paclitaxel TDM, clinical adoption has been limited due to the challenges with sample collection and analysis. Based on our review, we strongly recommend TDM for patients receiving every 3-week paclitaxel in combination with a platinum agent for advanced NSCLC, due to the prospectively demonstrated clinical benefits, and find moderate evidence to recommend TDM for paclitaxel 3-hour infusions for other tumor types and preliminary evidence suggesting potential usefulness for paclitaxel administered by 1-hour infusions.

The breast cancer tumor microenvironment and precision medicine: immunogenicity and conditions favoring response to immunotherapy

Some main recent researches that have dissected tumor microenvironment (TME) by imaging mass cytometry (IMC) in different subtypes of primary breast cancer samples were considered. The many phenotypic variants, clusters of epithelial tumor and immune cells, their structural features as well as the main genetic aberrations, sub-clonal heterogeneity and their systematic classification also have been examined. Mutational evolution has been assessed in primary and metastatic breast cancer samples. Overall, based on these findings the current concept of precision medicine is questioned and challenged by alternative therapeutic strategies. In the last two decades, immunotherapy as a powerful and harmless tool to fight cancer has received huge attention. Thus, the tumor immune microenvironment (TIME) composition, its prognostic role for clinical course as well as a novel definition of immunogenicity in breast cancer are proposed. Investigational clinical trials carried out by us and other findings suggest that G0-G1 state induced in endocrine-dependent metastatic breast cancer is more suitable for successful immune manipulation. Residual micro-metastatic disease seems to be another specific condition that can significantly favor the immune response in breast and other solid tumors.

Efficacy and safety of first-line therapy in patients with HER2-positive advanced breast cancer: a network meta-analysis of randomized controlled trials

PURPOSE

The numerous first-line treatment regimens for human epidermal growth factor receptor 2 (HER2)-positive advanced breast cancer (ABC) necessitate a comprehensive evaluation to inform clinical decision-making. We conducted a Bayesian network meta-analysis (NMA) to compare the efficacy and safety of different interventions.

METHODS

We systematically searched for relevant randomized controlled trials (RCTs) in Pubmed, Embase, Cochrane Library and online abstracts from inception to June 1, 2023. NMA was performed to calculate and analyze progression-free survival (PFS), overall survival (OS), objective response rate (ORR), and adverse events of grade 3 or higher (≥ 3 AEs).

RESULTS

Out of the 10,313 manuscripts retrieved, we included 28 RCTs involving 11,680 patients. Regarding PFS and ORR, the combination of trastuzumab with tyrosine kinase inhibitors (TKIs) was more favorable than dual-targeted therapy. If only using trastuzumab, combination chemotherapy is superior to monochemotherapy in terms of PFS. It is important to note that the addition of anthracycline did not result in improved PFS. For patients with hormone receptor-positive HER2-positive diseases, dual-targeted combined with endocrine therapy showed better benefit in terms of PFS compared to dual-targeted alone, but it did not reach statistical significance. The comprehensive analysis of PFS and ≥ 3 AEs indicates that monochemotherapy combined with dual-targeted therapy still has the optimal balance between efficacy and safety.

CONCLUSION

Monochemotherapy (Docetaxel) plus dual-target (Trastuzumab and Pertuzumab) therapy remains the optimal choice among all first-line treatment options for ABC. The combination of trastuzumab with TKIs (Pyrotinib) demonstrated a significant improvement in PFS and ORR, but further data are warranted to confirm the survival benefit.

Efficacy, Safety, Pharmacokinetics, and Immunogenicity of DRL-Trastuzumab Versus Herceptin in Human Epidermal Growth Factor Receptor 2-Positive Metastatic Breast Cancer: A Randomized Controlled Trial

PURPOSE

Dr Reddy's Laboratories Trastuzumab (DRL_TZ) is a biosimilar to Herceptin under development. The present study was conducted to evaluate efficacy, safety, pharmacokinetics (PKs), and immunogenicity of DRL_TZ in comparison with the reference medicinal product (RMP) along with concomitant weekly paclitaxel in patients with human epidermal growth factor receptor 2 (HER2)-positive metastatic breast cancer (MBC).

METHODS

This was a randomized, double-blind study in female patients with HER2-positive MBC, randomly assigned in a 1:1 ratio to receive either DRL_TZ or the RMP, that is, an innovator product sourced from the European region, along with additional chemotherapy, as first-line treatment for up to 24 weeks. The primary end point was the best overall response rate (ORR) as per RECIST 1.1 criteria. Progression-free survival rate at 6 months (PFS6), safety, immunogenicity, and PK parameters were assessed as secondary end points.

RESULTS

A total of 164 patients were randomly assigned to receive either DRL_TZ or the RMP. Best ORR in the per-protocol population was comparable, 91.9% (93.3% CI, 83.2 to 96.3) versus 82.1% (93.3% CI, 72.0 to 89.1) in DRL_TZ and RMP arms, respectively; the difference between the arms was 9.8% with a 93.3% CI of -1.3 to 20.8. The PFS6 rate, safety, PK profile, and antidrug antibody incidence were comparable. An additional 44 patients were recruited in the postrandomization phase, in an open-label manner, and started on DRL_TZ to generate more data on efficacy, safety, and immunogenicity. The additional data with DRL_TZ, when pooled, were similar to the RMP data.

CONCLUSION

DRL_TZ was found to have similar efficacy and comparable safety, PK, and immunogenicity profiles as the RMP.

Trastuzumab Combined With Ramucirumab and Paclitaxel in Patients With Previously Treated Human Epidermal Growth Factor Receptor 2-Positive Advanced Gastric or Gastroesophageal Junction Cancer

PURPOSE

Trastuzumab-containing chemotherapy is the recommended first-line regimen for human epidermal growth factor receptor 2 (HER2)-positive advanced gastric or gastroesophageal junction (G/GEJ) cancer. We evaluated the safety and efficacy of trastuzumab combined with ramucirumab and paclitaxel as second-line treatment for HER2-positive G/GEJ cancer.

PATIENTS AND METHODS

Patients with HER2-positive advanced G/GEJ cancer who progressed after first-line treatment with trastuzumab-containing chemotherapy were enrolled from five centers in the Republic of Korea. Patients were administered a 28-day cycle of trastuzumab (once on days 1, 8, 15, and 22: 2 mg/kg followed by 4 mg/kg loading dose), ramucirumab (once on days 1 and 15: 8 mg/kg), and paclitaxel (once on days 1, 8, and 15: dose level 1, 80 mg/m2; or dose level -1, 70 mg/m2). Phase II was conducted with the recommended phase II dose (RP2D). Primary end points were determination of RP2D during phase Ib and investigator-assessed progression-free survival (PFS) in patients treated with RP2D.

RESULTS

Dose-limiting toxicity at dose level 1 was not documented during phase Ib, and a full dose combination was selected as the RP2D. Among 50 patients with a median follow-up duration of 27.5 months (95% CI, 17.4 to 37.6), median PFS and overall survival were 7.1 months (95% CI, 4.8 to 9.4) and 13.6 months (95% CI, 9.4 to 17.7), respectively. Objective response rate was 54% (27 of 50, including one complete response), and disease control rate was 96% (48 of 50). Loss of HER2 expression was observed in 34.8% (8 of 23) patients after first-line treatment, and no definite association between HER2 expression and the outcome was revealed. Safety profiles were consistent with previous reports.

CONCLUSION

Trastuzumab combined with ramucirumab and paclitaxel showed appreciable efficacy with manageable safety profiles in patients with previously treated HER2-positive G/GEJ cancer.

Host genetic background regulates the capacity for anti-tumor antibody-dependent phagocytosis

Background

Antitumor antibody, or targeted immunotherapy, has revolutionized cancer treatment and markedly improved patient outcomes. A prime example is the monoclonal antibody (mAb) trastuzumab, which targets human epidermal growth factor receptor 2 (HER2). However, like many targeted immunotherapies, only a subset of patients benefit from trastuzumab long-term. In addition to tumor-intrinsic factors, we hypothesize that host genetics may influence subsequent immune activation.

Methods

To model the human population, we produced F1 crosses of genetically heterogeneous Diversity Outbred (DO) mice with BALB/c mice (DOCF1). Distinct DOCF1 mice were orthotopically implanted with the BALB/c-syngeneic TUBO mammary tumor line, which expresses the HER2 ortholog rat neu. Treatment with anti-neu mAb clone 7.16.4 began once tumors reached ∼200 mm ³ . Genetic linkage and quantitative trait locus (QTL) effects analyses in R/qtl2 identified loci associated with tumor growth rates. Locus validation was performed with BALB/c F1 crosses with recombinant-inbred Collaborative Cross (CC) strains selected for therapy-associated driver genetics (CCxCF1). The respective roles of natural killer (NK) cells and macrophages were investigated by selective depletion in vivo. Ex vivo macrophage antibody-dependent phagocytosis (ADCP) assays were evaluated by confocal microscopy using 7.16.4-opsonized E2Crimson-expressing TUBO tumor cells.

Results

We observed a divergent response to anti-tumor antibody therapy in DOCF1 mice. Genetic linkage analysis detected a locus on chromosome 10 that correlates to a robust response to therapy, which was validated in CCxCF1 models. Single-cell RNA sequencing of tumors from responder and non-responder models identified key differences in tumor immune infiltrate composition, particularly within macrophage (Mφ) subsets. This is further supported by ex vivo analysis showing Mφ ADCP capacity correlates to in vivo treatment outcomes in both DOCF1 and CCxCF1 models.

Conclusions

Host genetics play a key regulatory role in targeted immunotherapy outcomes, and putative causal genes are identified in murine chromosome 10 which may govern Mφ function during ADCP.

Chromosomal Instability as Enabling Feature and Central Hallmark of Breast Cancer

Chromosomal instability (CIN) has become a topic of great interest in recent years, not only for its implications in cancer diagnosis and prognosis but also for its role as an enabling feature and central hallmark of cancer. CIN describes cell-to-cell variation in the number or structure of chromosomes in a tumor population. Although extensive research in recent decades has identified some associations between CIN with response to therapy, specific associations with other hallmarks of cancer have not been fully evidenced. Such associations place CIN as an enabling feature of the other hallmarks of cancer and highlight the importance of deepening its knowledge to improve the outcome in cancer. In addition, studies conducted to date have shown paradoxical findings about the implications of CIN for therapeutic response, with some studies showing associations between high CIN and better therapeutic response, and others showing the opposite: associations between high CIN and therapeutic resistance. This evidences the complex relationships between CIN with the prognosis and response to treatment in cancer. Considering the above, this review focuses on recent studies on the role of CIN in cancer, the cellular mechanisms leading to CIN, its relationship with other hallmarks of cancer, and the emerging therapeutic approaches that are being developed to target such instability, with a primary focus on breast cancer. Further understanding of the complexity of CIN and its association with other hallmarks of cancer could provide a better understanding of the cellular and molecular mechanisms involved in prognosis and response to treatment in cancer and potentially lead to new drug targets.

The adverse effects of trastuzumab-containing regimes as a therapy in breast cancer: A piggy-back systematic review and meta-analysis

BACKGROUND

Trastuzumab is a valuable therapy option for women with ERBB2(HER2)+ breast cancer tumours, often used in combination with chemotherapy and alongside other therapies. It is known to have adverse effects, but these have proved difficult to separate from the effects of other concurrent therapies patients are usually taking. This study aims to assess the adverse effects specifically attributable to trastuzumab, and whether they vary by patient subgroup or concurrent therapies.

METHODS

As registered on PROSPERO (CRD42019146541), we used previous systematic reviews as well as the clinicaltrials.gov registry to identify randomised controlled trials in breast cancer which compared treatment regimes with and without trastuzumab. Neoadjuvant, adjuvant and metastatic settings were examined. Data was extracted from those which had, as of July 2022, reported adverse events. Risk of bias was assessed using ROB2. Primary outcomes were adverse events of any type or severity (excluding death). A standard random-effects meta-analysis was performed for each outcome independently. In order to ascertain whether adverse effects differed by individual factors such as age or tumour characteristics, or by use of trastuzumab concurrently with hormone therapy, we examined individual-level patient data for one large trial, HERA.

RESULTS

79 relevant trials were found, of which 20 contained comparable arms of trastuzumab-containing therapy and corresponding matched therapy without trastuzumab. This allowed a comparison of 8669 patients receiving trastuzumab versus 9556 receiving no trastuzumab, which gave a list of 25 statistically and clinically significant adverse effects related to trastuzumab alone: unspecified pain, asthenia, nasopharyngitis, skin disorders (mainly rash), dyspepsia, paraesthesia, infections (often respiratory), increased lacrimation, diarrhoea, myalgia, oedema (limb/peripheral), fever, nose bleeds, cardiac events, insomnia, cough, back pain, dyspnoea, chills, dizziness or vertigo, hypertension, congestive heart failure, increased levels of aspartate aminotransferase, gastrointestinal issues and dehydration. Analysis of individual patient-level data from 5102 patients suggested that nausea is slightly more likely for women taking trastuzumab who are ER+ /also taking hormone therapy than for those who are ER-/not taking hormone therapy; no other potential treatment-subgroup interactions were detected. We found no evidence for significantly increased rates of neutropenia, anaemia or lymphopenia in patients on trastuzumab-containing regimes compared to those on comparable regimes without trastuzumab.

CONCLUSIONS

This meta-analysis should allow clinicians and patients to better identify and quantify the potential adverse effects of adding trastuzumab to their treatment regime for breast cancer, and hence inform their decision-making. However, limitations include serious risk of bias due to heterogeneity in reporting of the outcomes and the open-label nature of the trials.

Comparison of tumors with HER2 overexpression versus HER2 amplification in HER2-positive breast cancer patients

Background

Human epidermal growth factor receptor 2 (HER2)-positive tumors are defined by protein overexpression (3+) or gene amplification using immunohistochemistry (IHC) or fluorescence in situ hybridization (FISH), respectively. HER2-positive tumors have historically included both IHC(3+) and IHC(2+, equivocal)/FISH(+) tumors and received the same treatment. Differences in biology between these two tumor types, however, are poorly understood. Considering anti-HER2 drugs bind directly to HER2 protein on the cell surface, we hypothesized anti-HER2 therapies would be less effective in IHC(2+)/FISH(+) tumors than in IHC(3+) tumors, leading to differences in patient outcomes.

Methods

A total of 447 patients with HER2-positive invasive carcinoma who underwent curative surgery were retrospectively investigated. HER2 status was assessed in surgical specimens, except in patients who received neo-adjuvant chemotherapy, where biopsy specimens were employed.

Results

Age, tumor size, lymph node status and ER status were independent factors relating to disease-free-survival, but no difference was observed between IHC(3+) and IHC(2+)/FISH(+) tumors. Kaplan-Meier analysis found patient outcomes did not differ, even after stratifying into those that did (n = 314), or did not (n = 129), receive chemotherapy with anti-HER2 drugs. In 134 patients who received NAC, pathological complete response rates in IHC(3+) and IHC(2+)/FISH(+) tumors were 45% and 21%, respectively. Survival after developing metastasis was significantly shorter in the IHC(2+)/FISH(+) group.

Conclusions

The prognosis of patients with IHC(2+)/FISH(+) tumors did not differ from IHC(3+) tumors. However, the significance of HER2 protein overexpression in relation to treatment response remains unclear and warrants further investigations.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12885-022-09351-4.

Comparative review of pharmacological therapies in individuals with HER2-positive advanced breast cancer with focus on hormone receptor subgroups

Breast cancer is the fifth leading cause of cancer-related deaths worldwide. The randomized controlled trials (RCTs) of targeted therapies in human epidermal receptor 2 (HER2)-positive advanced breast cancer (ABC) have provided an evidence base for regulatory and reimbursement agencies to appraise the use of cancer therapies in clinical practice. However, a subset of these patients harbor additional biomarkers, for example, a positive hormone receptor status that may be more amenable to therapy and improve overall survival (OS). This review seeks to explore the reporting of evidence for treatment effects by the hormone receptor status using the RCT evidence of targeted therapies for HER2-positive ABC patients. Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) guidelines were followed to identify published RCTs. Extracted data were synthesized using network meta-analysis to obtain the relative effects of HER2-positive-targeted therapies. We identified a gap in the reporting of the effectiveness of therapies by the hormone receptor status as only 15 out of 42 identified RCTs reported hormone receptor subgroup analyses; the majority of which reported progression-free survival but not OS or the overall response rate. In conclusion, we recommend that future trials in ABC should report the effect of cancer therapies in hormone receptor subgroups for all outcomes.

Hypermethylation of DLG3 Promoter Upregulates RAC1 and Activates the PI3K/AKT Signaling Pathway to Promote Breast Cancer Progression

Objective

This investigation aimed to figure out the relation between discs large homolog 3 (DLG3) expression and the progression and prognosis of breast cancer (BC).

Methods

qRT-PCR was utilized for confirming DLG3 expression and RAC1 mRNA expression in BC tissues and cells. Subsequently, after overexpression or interference of DLG3, the changes of the biological activities of BC cells, including cell proliferation, migration, invasion, and apoptosis, were detected through CCK-8, colony formation assay, wound healing assay, transwell assay, and flow cytometry, respectively. Furthermore, western blotting was utilized to measure the protein expression of DLG3 and RAC1, as well as related proteins of epithelial-mesenchymal transition (EMT) and the PI3K/AKT signaling pathway.

Results

At both cellular and tissue level in BC, DLG3 was downregulated and methylation level was upregulated; RAC1 showed an opposite change and was of a negative correlation with DLG3. In MCF-7 and HCC1937, we found that the upregulation of DLG3 could inhibit RAC1 expression as well as cell proliferation, invasion, migration, and EMT, while promoting apoptosis. Also, DLG3 inhibited the activation of the P13K/AKT pathway.

Conclusion

Hypermethylation of DLG3 promoter upregulates RAC1 and activates the PI3K/AKT pathway, thus promoting BC progression. This conclusion provides ideas and experimental basis for improving and treating BC patients.

Efficacy and Safety of Anti-HER2 Agents in Combination With Chemotherapy for Metastatic HER2-Positive Breast Cancer Patient: A Network Meta-Analysis

Background

The presence of anti-HER2 agents, such as trastuzumab, pertuzumab, and trastuzumab emtansine (T-DM1), significantly improved the prognosis of metastatic HER2-positive (HER2+) breast cancers (BC). However, drug resistance and disease progression are still common. In order to further improve the treatment efficacy, new clinical trials about anti-HER2 agents in combination with chemotherapy are growing rapidly. We conducted the network meta-analysis to synthesize evidences of clinical trials to identify the best therapy for metastatic HER2+ BC.

Methods

A systematic search of randomized controlled trials regarding anti-HER2 agents in combination with chemotherapy for advanced or metastatic breast cancers up to May 2020 was conducted in Embase, PubMed, and the Cochrane Library. The primary outcome was progression-free survival (PFS). The secondary outcomes were overall survival (OS), objective response rate (ORR), and safety. Bayesian network meta-analysis was conducted to synthesize the results and rank the therapies.

Results

Twenty-six studies, including 16 studies for first-line treatments and 10 studies for second- or later-line treatments were included in the network meta-analysis. For first-line studies, the THP (taxanes + trastuzumab + pertuzumab) regimen exhibited the highest probability to be the optimal treatment in all efficacy outcomes and moderate safety. For second- or later-line studies, the T-DM1 and XHTuC (capecitabine + trastuzumab + tucatinib) regimens ranked top two in all efficacy outcomes according to the surface under the cumulative ranking (SUCRA) results. T-DM1 ranked first in PFS and OS whereas XHTuC ranked first in ORR. The safety outcomes of T-DM1 and XHTuC were acceptable.

Conclusions

THP was still the optimal first-line treatment for metastatic HER2+ BC. T-DM1 and XHTuC were recommended for second-line treatments.

Systematic Review Registration

INPLASY.com, identifier (INPLASY202090086).

Resistance to Intervention: Paclitaxel in Breast Cancer

Breast cancer stands as the most prevalent cancer in women globally, and contributes to the highest percentage of mortality due to cancer-related deaths in women. Paclitaxel (PTX) is heavily relied on as a frontline chemotherapy drug in breast cancer treatment, especially in advanced metastatic cancer. Generation of resistance to PTX often derails clinical management and adversely affects patient outcomes. Understanding the molecular mechanism of PTX resistance is necessary to device methods to aid in overcoming the resistance. Recent studies exploring the mechanism of development of PTX resistance have led to unveiling of a range novel therapeutic targets. PTX resistance pathways that involve major regulatory proteins/RNAs like RNF8/Twist/ROR1, TLR, ErbB3/ErbB2, BRCA1- IRIS, MENA, LIN9, MiRNA, FoxM1 and IRAK1 have expanded the complexity of resistance mechanisms, and brought newer insights into the development of drug targets. These resistance-related targets can be dealt with synthetic/natural therapeutics in combination with PTX. The present review encompasses the recent understanding of PTX resistance mechanisms in breast cancer and possible therapeutic combinations to overcome resistance.

Current treatment options for HER2-positive breast cancer patients with brain metastases

Brain metastases (BMs) are frequently associated with HER2+ breast cancer (BC). Their management is based on a multi-modal strategy including both local treatment and systemic therapy. Despite therapeutic advance, BMs still have an adverse impact on survival and quality of life and the development of effective systemic therapy to prevent and treat BMs from HER2 + BC represents an unmet clinical need. Trastuzumab-based therapy has long been the mainstay of systemic therapy and over the last two decades other HER2-targeted agents including lapatinib, pertuzumab and trastuzumab emtansine, have been introduced in the clinical practice. More recently, novel agents such as neratinib, tucatinib and trastuzumab deruxtecan have been developed, with interesting activity against BMs. Further research is needed to better elucidate the best sequence of these agents and their combination with local treatment.

Efficacy, Safety, and Immunogenicity of HLX02 Compared with Reference Trastuzumab in Patients with Recurrent or Metastatic HER2-Positive Breast Cancer: A Randomized Phase III Equivalence Trial

BACKGROUND

HLX02 is an approved biosimilar of trastuzumab.

OBJECTIVE

This study aimed to evaluated the efficacy, safety, and immunogenicity of HLX02 compared with reference trastuzumab in patients with human epidermal growth factor receptor 2 (HER2)-positive recurrent or metastatic breast cancer.

PATIENTS AND METHODS

This randomized, double-blind, phase III study was conducted at 89 centers in China, the Philippines, Poland, and Ukraine. Eligible patients were randomized (1:1) to receive HLX02 or European Union (EU)-sourced trastuzumab (initial dose of 8 mg/kg, followed by 6 mg/kg every 3 weeks for up to 12 months) in combination with docetaxel intravenously. The primary endpoint was overall response rate up to week 24 (ORR₂₄). Equivalence was declared if the 95% confidence interval (CI) of difference was within ± 13.5%. Safety and immunogenicity were evaluated in patients who received at least one dose of study medication.

RESULTS

Between 11 November 2016 and 10 July 2019, a total of 649 patients were enrolled. The ORR₂₄ was 71.3 and 71.4% in the HLX02 (n = 324) and EU-trastuzumab (n = 325) groups, with a difference of - 0.1% (95% CI - 7 to 6.9), which fell entirely in the predefined equivalence margins. No statistically significant differences were observed in all secondary efficacy analyses. Safety profiles and immunogenicity were comparable in HLX02 and EU-trastuzumab groups. In total, 98.8% of patients in each group experienced at least one treatment-emergent adverse event (TEAE), 23.8 and 24.9% experienced serious TEAEs, and 0.6% in each group had antidrug antibodies.

CONCLUSIONS

Among patients with HER2-positive recurrent or metastatic breast cancer, HLX02 demonstrated equivalent efficacy and similar safety and immunogenicity to reference trastuzumab.

CLINICAL TRIAL REGISTRATION

Chinadrugtrials.org CTR20160526 (12 September 2016), ClinicalTrials.gov NCT03084237 (20 March 2017), EudraCT 2016-000206-10 (27 April 2017).

Survival before and after the introduction of pertuzumab and T-DM1 in HER2-positive advanced breast cancer, a study of the SONABRE Registry

Purpose

Immediate and proper implementation of a new and more potent therapy is important to ensure that the patient achieves the best possible outcome. This study aimed to examine whether the real-world overall survival (OS) has improved in patients with human epidermal growth factor receptor 2-positive (HER2 +) advanced breast cancer (ABC) since the market release of pertuzumab and T-DM1. Furthermore, we aimed to assess the implementation and survival rates per hormone receptor (HR) subtype.

Patients and methods

We included 493 systemically treated patients consecutively diagnosed with HER2 + ABC in 2008–2017 from the SOutheast Netherlands Advanced BREast cancer (SONABRE) Registry. Median OS was obtained using the Kaplan–Meier method and differences between periods (2008–2012 versus 2013–2017) were tested using multivariable Cox proportional hazards regression modeling. The 3-year implementation rates were estimated for any HER2-targeted therapy, pertuzumab, and T-DM1 by using the competing risk method and calculated from the date of diagnosis of ABC to start of HER2-targeted therapy of interest.

Results

The median OS in 2008–2012 versus 2013–2017 was 28.3 versus 39.7 months in all patients (adjusted hazard ratio (adjHR) 0.85, 95%CI 0.66–1.08), 29.9 versus 36.3 months in patients with HR + /HER2 + disease (adjHR 0.97, 95%CI 0.72–1.32), and 22.7 versus 40.9 months in patients with HR-/HER2 + disease (adjHR 0.59, 95%CI 0.38–0.92). Any HER2-targeted therapy was used in 79% of patients in 2008–2012 and in 84% in 2013–2017. The use of pertuzumab and T-DM1 in 2013–2017 was 48% and 29%, respectively. For patients diagnosed with HR + /HER2 + and HR-/HER2 + disease, implementation rates in 2013–2017 were , respectively, 77% and 99% for any HER2-targeted therapy, 38% and 69% for pertuzumab, and 24% and 40% for T-DM1.

Conclusion

The survival of patients with HER2 + ABC improved since the introduction of pertuzumab and T-DM1. There is room for improvement in implementation of these HER2-targeted therapies, especially in patients with HR + /HER2 + disease.

Supplementary Information

The online version contains supplementary material available at 10.1007/s10549-021-06178-8.

A phase I safety study of topical calcitriol (BPM31543) for the prevention of chemotherapy-induced alopecia

PURPOSE

Chemotherapy-induced alopecia (CIA) negatively affects psychosocial health and quality of life (QoL). Currently, there are no approved pharmacologic agents to prevent CIA. Here, we evaluated the safety, tolerability, and potential signal of efficacy of topical calcitriol (BPM31543) on CIA prevention.

MATERIALS AND METHODS

This Phase 1 trial included 23 female patients with breast cancer, gynecologic cancer, or sarcomas receiving a taxane-based chemotherapy. Patients received a 3 + 3 dose-escalation regimen at 5, 10, 20, 40, 60, and 80 μg/mL, with 3-6 patients per group. Patients applied topical BPM31543 to the scalp twice a day for 2 weeks prior to chemotherapy and continued until chemotherapy treatment was completed. The maximum tolerated dose (MTD) during first 28 day application was determined. Adverse event (AE) monitoring, pharmacokinetics, blinded photographic assessments, and patient self-assessment were evaluated.

RESULTS

Out of 23 patients treated with BPM31543, 8 patients experienced at least 1 treatment-related adverse event (AE). The majority of AEs were mild to moderate in severity. Only 1 patient experienced SAEs (vomiting, nausea, fever, and flank pain) considered treatment related. Alopecia < 50% from baseline was observed in 8 patients at Week 7, and, of which 2 patients had < 50% alopecia maintained at Week 15. There were no detectable effects of topical BPM31543 on serum levels of calcitriol.

CONCLUSIONS

BPM31543 applied topically twice daily to the scalp is safe and well tolerated in patients receiving taxane-based chemotherapy. No DLT was observed at up to 80 µg/mL, and MTD was not reached. Based on the data from this trial, BPM31543 represents a promising therapy and warrants further investigation in Phase 2/3 trials.

Cardiac monitoring in HER2-positive patients on trastuzumab treatment: A review and implications for clinical practice

Trastuzumab prolongs progression-free and overall survival in patients with human epidermal growth factor receptor 2 (HER2) positive breast cancer. However, trastuzumab treatment is hampered by cardiotoxicity, defined as a left ventricular ejection fraction (LVEF) decline with a reported incidence ranging from 3 to 27% depending on variable factors. Early identification of patients at increased risk of trastuzumab-induced myocardial damage is of great importance to prevent deterioration to irreversible cardiotoxicity. Although current cardiac monitoring with multi gated acquisition (MUGA) scanning and/or conventional 2D-echocardiography (2DE) have a high availability, their reproducibility are modest, and more sensitive and reliable techniques are needed such as 3D-echocardiography (3DE) and speckle tracking echocardiography (STE). But which other diagnostic imaging modalities are available for patients before and during trastuzumab treatment? In addition, what is the optimal frequency and duration of cardiac monitoring? At last, which biomarker monitoring strategies are currently available for the identification of cardiotoxicity in patients treated with trastuzumab?

The role of chemotherapy in treatment of advanced breast cancer: an overview for clinical practice

This review aims to evaluate the role of chemotherapy-containing regimens in the treatment of advanced breast cancer (ABC), with the purpose to optimize selection, sequencing and duration of treatment with the currently available agents for clinical practice. Data from observational as well as randomized phase II and III studies were included. Chemotherapy yielded a median overall survival (OS) of 2 years in registration studies, with comparable efficacy of different agents. Combining chemotherapy agents did not yield OS improvement and caused greater toxicity compared with single-agent chemotherapy. Continuing chemotherapy till progression or unacceptable toxicity generated greater efficacy without detrimental impact on quality of life compared with a limited amount of cycles. In real-world studies, benefits after third-line chemotherapy were modest compared with first- and second-line. Furthermore, effects of previous chemotherapy predicted effects of next-line therapy in real-world. Physicians increasingly prescribed capecitabine or taxanes as first- or second-line chemotherapy over time.

Evaluating Trastuzumab in the treatment of HER2 positive breast cancer

The transmembrane oncoprotein HER2 is encoded by ERBB2 gene and overexpressed in around 20% of invasive breast cancers. It can be specifically targeted by Trastuzumab (Herceptin®), a humanised IgG1 antibody. Trastuzumab has been regarded as one of the most effective therapeutic drugs targeted to HER2 positive cancers. However, there are drawbacks, notably cardiotoxicity and resistance, which have raised awareness in clinical use. Therefore, understanding the mechanism of action is vital to establish improved therapeutic strategies. Here we evaluate Trastuzumab application in the treatment of HER2 positive breast cancer, focusing on its mechanistic actions and clinical effectiveness. Alternative therapies targeting the HER2 receptor and its downstream anomalies will also be discussed, as these could highlight further targets that could be key to improving clinical outcomes.

The Japanese Breast Cancer Society Clinical Practice Guidelines for systemic treatment of breast cancer, 2018 edition

Purpose

We present the English version of The Japanese Breast Cancer Society (JBCS) Clinical Practice Guidelines for systemic treatment of breast cancer, 2018 edition.

Methods

The JBCS formed a task force to update the JBCS Clinical Practice Guidelines, 2015 edition, according to Minds Handbook for Clinical Practice Guideline Development 2014. First, we set multiple outcomes for each clinical question (CQ). Next, quantitative or qualitative systematic review was conducted for each of the multiple outcomes, and the strength of recommendation for the CQ was taken into consideration during meetings, with the aim of finding a balance between benefit and harm. Finalized recommendations from each session were confirmed through discussion and voting at the recommendation decision meeting.

Results

The recommendations, the strength of recommendation and the strength of evidence were determined based on systemic literature reviews and the meta-analyses for each CQ.

Conclusion

The JBCS updated the Clinical Practice Guidelines for systemic treatment of breast cancer.

Electronic supplementary material

The online version of this article (10.1007/s12282-020-01085-0) contains supplementary material, which is available to authorized users.

Effect of cryotherapy on dose of adjuvant paclitaxel in early-stage breast cancer

BACKGROUND

Chemotherapy-induced peripheral neuropathy (CIPN) is a dose-limiting toxicity of paclitaxel. Though no pharmacological agents have been identified to prevent CIPN, cryotherapy with frozen gloves and socks may reduce the risk of developing CIPN and thereby increase the likelihood of patients completing the planned dose of paclitaxel.

PATIENTS AND METHODS

Among women with early-stage breast cancer who received at least one cycle of paclitaxel, 119 were included in the 2016 cohort who received cryotherapy when they developed symptoms of CIPN, and 96 patients in the 2017 cohort who received prophylactic cryotherapy. From electronic patient records, data were abstracted on dates and doses of adjuvant paclitaxel, dose reductions, cycle delays, symptoms of CIPN, and whether and when frozen gloves and socks were used. The outcome was the proportion of patients completing the planned 720 mg/m² of paclitaxel cumulated over nine cycles. The hazard ratio (HR) of a dose-limiting event due to CIPN was estimated in a Cox proportional hazards model.

RESULTS

In the 2016 cohort, cryotherapy was needed due to symptoms of CIPN in 54 (45%) patients. Significantly, more patients, 77% in the 2017 cohort, completed the planned dose of 720 mg/m² compared with 64% in the 2016 cohort, p = 0.017. The HR of a dose reduction or cessation due to CIPN, adjusted for age and HER-2 status, was 0.50 (95% confidence interval 0.30-0.84), p = 0.009, for the 2017 cohort compared with the 2016 cohort.

CONCLUSIONS

The results of this study suggest that prophylactic cryotherapy may reduce the risk of a dose-limiting event due to CIPN and increase the proportion of patients completing the planned dose of paclitaxel in adjuvant treatment of early-stage breast cancer. Despite this, CIPN remains to be an important dose-limiting toxicity of paclitaxel.

PF-05280014 (a trastuzumab biosimilar) plus paclitaxel compared with reference trastuzumab plus paclitaxel for HER2-positive metastatic breast cancer: a randomised, double-blind study

Background

This randomised, double-blind study compared PF-05280014 (a trastuzumab biosimilar) with reference trastuzumab (Herceptin®) sourced from the European Union (trastuzumab-EU), when each was given with paclitaxel as first-line treatment for HER2-positive metastatic breast cancer.

Methods

Between 4 April 2014 and 22 January 2016, 707 participants were randomised 1:1 to receive intravenous PF-05280014 plus paclitaxel (PF-05280014 group; n = 352) or trastuzumab-EU plus paclitaxel (trastuzumab-EU group; n = 355). PF-05280014 or trastuzumab-EU was administered weekly (first dose 4 mg/kg, subsequent doses 2 mg/kg), with the option to change to a 3-weekly regimen (6 mg/kg) from Week 33. Treatment with PF-05280014 or trastuzumab-EU could continue until disease progression. Paclitaxel (starting dose 80 mg/m²) was administered on Days 1, 8 and 15 of 28-day cycles for at least six cycles or until maximal benefit of response. The primary endpoint was objective response rate (ORR), evaluating responses achieved by Week 25 and confirmed by Week 33, based on blinded central radiology review.

Results

The risk ratio for ORR was 0.940 (95% CI: 0.842–1.049). The 95% CI fell within the pre-specified equivalence margin of 0.80–1.25. ORR was 62.5% (95% CI: 57.2–67.6%) in the PF-05280014 group and 66.5% (95% CI: 61.3–71.4%) in the trastuzumab-EU group. As of data cut-off on 11 January 2017 (using data up to 378 days post-randomisation), there were no notable differences between groups in progression-free survival (median: 12.16 months in the PF-05280014 group vs. 12.06 months in the trastuzumab-EU group; 1-year rate: 54% vs. 51%) or overall survival (median: not reached in either group; 1-year rate: 89.31% vs. 87.36%). Safety outcomes and immunogenicity were similar between the treatment groups.

Conclusion

When given as first-line treatment for HER2-positive metastatic breast cancer, PF-05280014 plus paclitaxel demonstrated equivalence to trastuzumab-EU plus paclitaxel in terms of ORR.

CLINICAL TRIAL REGISTRATION

ClinicalTrials.gov, NCT01989676

Hair disorders in patients with cancer

Cytotoxic chemotherapies, molecularly targeted therapies, immunotherapies, radiotherapy, stem cell transplants, and endocrine therapies may lead to hair disorders, including alopecia, hirsutism, hypertrichosis, and pigmentary and textural hair changes. The mechanisms underlying these changes are varied and remain incompletely understood, hampering the development of preventive or therapeutic guidelines. The psychosocial impact of chemotherapy-induced alopecia has been well documented primarily in the oncology literature; however, the effect of other alterations, such as radiation-induced alopecia, hirsutism, and changes in hair color or texture on quality of life have not been described. This article reviews clinically significant therapy-related hair disorders in oncology patients, including the underlying pathophysiological mechanisms, severity grading scales, patient-reported quality of life questionnaires, management strategies, and future translational research opportunities.

Development and clinical application of anti-HER2 monoclonal and bispecific antibodies for cancer treatment

HER2-targeted immunotherapy consists of monoclonal antibodies (e.g. trastuzumab, pertuzumab), bispecific antibodies (e.g. MM-111, ertumaxomab) and activated T cells armed with anti-HER2 bispecific antibody (HER2Bi-aATC). Trastuzumab is a classic drug for the treatment of HER2 positive metastatic breast cancer. The combined application of pertuzumab, trastuzumab and paclitaxel has been suggested as a standard therapy for HER2 positive advanced breast cancer. The resistance to anti-HER2 antibody has resulted in disease progression. HER2-directed bispecific antibody may be a promising therapeutic approach for these patients. Ertumaxomab enhanced the interaction of immune effector cells and tumor cells. MM-111 simultaneously binds to HER2 and HER3 and blocks downstream signaling. Besides, HER2Bi-aATC is also an alternative therapeutic approach for HER2 positive cancers. In this review, we summarized the recent advancement of HER2-targeted monoclonal antibodies (trastuzumab, pertuzumab and T-DM1) and bispecific antibodies (MM-111, ertumaxomab and HER2Bi-aATC), especially focus on clinical trial results.

Incidence, Diagnosis, and Treatment of Cardiac Toxicity from Trastuzumab in Patients with Breast Cancer

PURPOSE OF REVIEW

Treatment with trastuzumab is a cornerstone of human epidermal growth factor receptor 2 (HER2)-overexpressing breast cancer treatment, but carries an unfortunate risk of toxicity to the cardiovascular system. Here we review recent findings on trastuzumab-associated cardiotoxicity, focusing on its incidence, diagnosis, and treatment.

RECENT FINDINGS

Screening with multigated acquisition scan (MUGA) or echocardiogram (ECHO) is recommended to assess cardiac function prior to and during trastuzumab therapy. Because trastuzumab-induced cardiotoxicity is typically reversible, cessation of trastuzumab and/or administration of first line heart failure agents effectively restores cardiac function in most cases. Severe trastuzumab-induced cardiotoxicity is rare enough that the risk-benefit ratio still weighs in favor of its use in the vast majority of patients with HER2+ breast cancer.

SUMMARY

An improved understanding of the pathophysiology underlying trastuzumab-induced cardiotoxicity and the identification of patients at highest risk will allow us to continue to safely administer trastuzumab in patients with breast cancer.

Evolution of anti-HER2 therapies for cancer treatment

The development of HER2-directed monoclonal antibodies and tyrosine kinase inhibitors have provided benefits to cancer patients, as well as produced many insights into the biology of the ErbB receptor family. Current therapies based on ErbB family members have resulted in improved overall survival with associated improvements in quality of life for the cancer patients that respond to treatment. Compared to monotherapy using either two antibodies to block the HER2 receptor blockade or combinatorial approaches with HER2 antibodies and standard therapies has provided additional benefits. Despite the therapeutic success of existing HER2 therapies, personalising treatment and overcoming resistance to these therapies remains a significant challenge. The heterogeneous intra-tumoural HER2 expression and lack of fully predictive and prognostic biomarkers remain significant barriers to improving the use of HER2 antibodies. Imaging modalities using radiolabelled pertuzumab and trastuzumab allow quantitative assessment of intra-tumoural HER2 expression, HER2 antibody saturation and the success of different drug delivery systems to be assessed. Molecular imaging with HER2 antibodies has the potential to be a non-invasive, predictive and prognostic technique capable of influencing therapeutic decisions, predicting response and failure of treatments as well as providing insights into receptor recycling and signalling. Similarly, conjugating HER2 antibodies with novel toxic payloads or combining HER2 antibodies with cellular immunotherapy provide exciting new opportunities for the management of tumours overexpressing HER2. Future research will lead to higher therapeutic responses, lower toxicities and providing insight into the mechanisms of resistance to HER2-targeted treatments.

Increased life expectancy as a result of non-hormonal targeted therapies for HER2 or hormone receptor positive metastatic breast cancer: A systematic review and meta-analysis

This article aimed to assess the clinical effectiveness of non-hormonal targeted therapies (TTs) in terms of increase of median progression-free survival (PFS) and overall survival (OS) in receptor-positive metastatic breast cancer (MBC) patients by performing a systematic review and meta-analysis. We systematically searched relevant randomized controlled trials and extracted data about number of patients on targeted and comparator therapy, receptor status, line of treatment, median PFS and OS, p values, hazard ratios (HRs) and 95% confidence intervals (CI). Inverse variance was used to estimate pooled HRs, chi-square test for heterogeneity and Jadad scale for quality were applied. Thirty-eight studies (n=17,192 patients) were eligible for inclusion. TTs added 3.3months to the median PFS [0.7-9.6; HRs 0.74, 95% CI 0.71-0.77] of receptor-positive MBC patients and prolonged their median OS with 3.5months [0-4.7; HRs 0.90, 95% CI 0.82-0.98]. The highest increase in median PFS of 3.6months was found in HER2-/hormone receptor(HR)+ patients, while the highest increase in median OS of 7.2months was observed in HER2+/HRmixed status patients. First-line TTs were most effective in increasing the median PFS in the HR+/HER2- group with 2.0months, and in the HER2+/HRmixed group by adding 4.7months to the median OS. Second-line TTs were most effective for HER2-/HR+ patients by adding 2.6months to their PFS, and for HER2+/HRmixed patients by adding 3.1months to their median OS. Albeit small, the gain in months of median PFS and median OS was significant. Importantly, the results reported show large variation, and thus routinely applying a personalized approach seems warranted.

Clinical effects of prior trastuzumab on combination eribulin mesylate plus trastuzumab as first-line treatment for human epidermal growth factor receptor 2 positive locally recurrent or metastatic breast cancer: results from a Phase II, single-arm, multicenter study

Eribulin mesylate, a novel nontaxane microtubule dynamics inhibitor in the halichondrin class of antineoplastic drugs, is indicated for the treatment of patients with metastatic breast cancer who previously received ≥2 chemotherapy regimens in the metastatic setting. Primary data from a Phase II trial for the first-line combination of eribulin plus trastuzumab in human epidermal growth factor receptor 2 positive patients showed a 71% objective response rate and tolerability consistent with the known profile of these agents. Here, we present prespecified analyses of efficacy of this combination based on prior trastuzumab use. Patients received eribulin mesylate 1.4 mg/m² (equivalent to 1.23 mg/m² eribulin [expressed as free base]) intravenously on days 1 and 8 plus trastuzumab (8 mg/kg intravenously/cycle 1, then 6 mg/kg) on day 1 of each 21-day cycle. Objective response rates, progression-free survival, and tolerability were assessed in patients who had and had not received prior adjuvant or neoadjuvant (neo/adjuvant) trastuzumab treatment. Fifty-two patients (median age: 59.5 years) received eribulin/trastuzumab for a median treatment duration of ~31 weeks; 40.4% (n=21) had been previously treated with neo/adjuvant trastuzumab prior to treatment with eribulin plus trastuzumab for metastatic disease (median time between neo/adjuvant and study treatment: 23 months). In trastuzumab-naïve patients (n=31) compared with those who had received prior trastuzumab, objective response rate was 77.4% versus 61.9%, respectively; duration of response was 11.8 versus 9.5 months, respectively; clinical benefit rate was 87.1% versus 81.0%, respectively; and median progression-free survival was 12.2 versus 11.5 months, respectively. The most common grade 3/4 treatment-emergent adverse events (occuring in ≥5% of patients) in patients who received prior trastuzumab versus trastuzumab naïve patients, respectively, were neutropenia (47.6% vs 32.3%), peripheral neuropathy (14.3% vs 25.8%), febrile neutropenia (14.3% vs 3.2%), fatigue (9.5% vs 6.5%), nausea (9.5% vs 0%), vomiting (9.5% vs 3.2%), and leukopenia (9.5% vs 3.2%). In patients with human epidermal growth factor receptor 2 positive metastatic breast cancer, first-line eribulin/trastuzumab treatment demonstrated substantial antitumor activity and was well tolerated, regardless of prior neo/adjuvant trastuzumab treatment.

Real-World Evidence: A Comparison of the Australian Herceptin Program and Clinical Trials of Trastuzumab for HER2-Positive Metastatic Breast Cancer

INTRODUCTION

Estimating the real-world cost-effectiveness of a new drug relies on understanding the differences between clinical trial data (pre-reimbursement) and clinical practice (post-reimbursement). This is important for decision makers when reviewing reimbursement decisions, prices, and considering other drugs for the same condition. Differences can arise from differences in patient characteristics, but also from the availability of new evidence and evolving treatment practices. This paper examines these issues using a case study.

METHODS

In 2001, the Australian Government funded trastuzumab for the treatment of HER2+ metastatic breast cancer through the Herceptin Program. The administrative arrangements of the Program resulted in rich observational data that captured information about patients treated with trastuzumab between 2001 and 2010 (n = 3830). The dataset included patient characteristics, dispensed medicines, medical service use and date of death.

RESULTS

Compared to participants in the clinical trials, patients were older, received more prior chemotherapies and a broader range of co-administered chemotherapies. Treatment practices differed from the clinical trials, but also changed over time. For example, in situ hybridization testing, rather than immunohistochemistry testing, and a three weekly administration schedule, rather than one weekly, were increasingly used. Compared to the clinical trials, patients administered trastuzumab with a concomitant chemotherapy generally experienced longer overall survival (151.3 weeks, 95 % CI: 142.6, 163.4), while those who received trastuzumab as a monotherapy experienced shorter overall survival (94.4 weeks, 95%CI: 86.4, 102.9). These findings may be due to a differing relative treatment effect in clinical practice, but may also be due to a range of other factors.

CONCLUSION

This analysis demonstrates the challenges for decision makers that arise because new evidence and evolving treatment practices create a gap between clinical trial data and real-world clinical practice and outcomes.

Twenty years of anti-HER2 therapy-associated cardiotoxicity

Over the past 20 years, the prognosis of HER2-positive breast cancer has been transformed by the development of anti-HER2 targeted therapies. In early clinical trials of trastuzumab (ie, the first anti-HER2 agent to be developed) cardiotoxicity became a major concern. In the first published phase 3 trial of trastuzumab, 27% of patients receiving anthracyclines and trastuzumab experienced cardiac events and 16% suffered from severe congestive heart failure. In subsequent trials conducted in advanced and early settings, the incidence of cardiac events was reduced through changes in chemotherapy regimens, more strict patient selection and close cardiac assessment. However, cardiotoxicity remains a significant problem in clinical practice that is likely to increase as new agents are approved and exposure times increase through improved patients' survival. Though numerous trials have led to improved understanding of many aspects of anti-HER2 therapy-related cardiotoxicity, its underlying physiopathology mechanisms are not well understood. The purpose of this article is to provide an in-depth review on anti-HER2 therapy-related cardiotoxicity, including data on both trastuzumab and the recently developed anti-HER2 targeted agents.

Meta-analysis of cardiovascular toxicity risks in cancer patients on selected targeted agents

PURPOSE

The purpose was to estimate the risk and severity of cardiovascular toxicities associated with selected targeted agents.

METHODS

We searched English-language literature for randomized clinical trials published between January 1, 2000 and November 30, 2013 of targeted cancer therapy drugs approved by the FDA by November 2010. One hundred ten studies were eligible. Using meta-analytic methods, we calculated the relative risks of several cardiovascular toxicities [congestive heart failure (CHF), decreased left ventricular ejection fraction (DLVEF), myocardial infarction (MI), arrhythmia, and hypertension (HTN)], adjusting for sample size using the inverse-variance technique. For each targeted agent and side effect, we calculated the number needed to harm.

RESULTS

Regarding CHF, trastuzumab showed significantly greater risk of all-grade and high-grade CHF. There was significant increased risk of all-grade DLVEF with sorafenib, sunitinib, and trastuzumab and high-grade DLVEF with bevacizumab and trastuzumab. Sorafenib was associated with significant increased all-grade risk of MI based on one study. None was associated with high-grade risk of MI or increased risk of arrhythmia. Bevacizumab, sorafenib, and sunitinib had significant increased risk of all-grade and high-grade HTN.

CONCLUSIONS

Several of the targeted agents were significantly associated with increased risk of specific cardiovascular toxicities, CHF, DLVEF, and HTN. Several had significant increased risk for high-grade cardiovascular toxicities (CHF, DLVEF, and HTN). Patients receiving such therapy should be closely monitored for these toxicities and early and aggressive treatment should occur. However, clinical experience has demonstrated that some of these toxicities may be reversible and due to secondary effects.

Progression-free survival as surrogate end point for overall survival in clinical trials of HER2-targeted agents in HER2-positive metastatic breast cancer

BACKGROUND

The gold standard end point in randomized clinical trials in metastatic breast cancer (MBC) is overall survival (OS). Although therapeutics have been approved based on progression-free survival (PFS), its use as a primary end point is controversial. We aimed to assess to what extent PFS may be used as a surrogate for OS in randomized trials of anti-HER2 agents in HER2+ MBC.

METHODS

Eligible trials accrued HER2+ MBC patients in 1992-2008. A correlation approach was used: at the individual level, to estimate the association between investigator-assessed PFS and OS using a bivariate model and at the trial level, to estimate the association between treatment effects on PFS and OS. Correlation values close to 1.0 would indicate strong surrogacy.

RESULTS

We identified 2545 eligible patients in 13 randomized trials testing trastuzumab or lapatinib. We collected individual patient data from 1963 patients and retained 1839 patients from 9 trials for analysis (7 first-line trials). During follow-up, 1072 deaths and 1462 progression or deaths occurred. The median survival time was 22 months [95% confidence interval (CI) 21-23 months] and the median PFS was 5.7 months (95% CI 5.5-6.1 months). At the individual level, the Spearman correlation was equal to ρ = 0.67 (95% CI 0.66-0.67) corresponding to a squared correlation value of 0.45. At the trial level, the squared correlation between treatment effects (log hazard ratios) on PFS and OS was provided by R(2) = 0.51 (95% CI 0.22-0.81).

CONCLUSIONS

In trials of HER2-targeted agents in HER2+ MBC, PFS moderately correlates with OS at the individual level and treatment effects on PFS correlate moderately with those on overall mortality, providing only modest support for considering PFS as a surrogate. PFS does not completely substitute for OS in this setting.

Efficacy, safety and administration timing of trastuzumab in human epidermal growth factor receptor 2 positive breast cancer patients: A meta-analysis

Trastuzumab has been demonstrated to be an effective treatment in patients with human epidermal growth factor receptor-2 (HER-2) positive breast cancer (BC); however, inconsistent results with regards to the long-term survival benefits, safety and optimal administration timing of trastuzumab exist. The present meta-analysis investigated these inconsistencies in patients with HER-2 positive BC that received adjuvant or neoadjuvant trastuzumab. Computerized and manual searches were used to identify eligible randomized control trials (RCTs) to include in the analysis. Based on a fixed or random effects model, hazard and risk ratios were calculated and used to assess the survival advantages and risks of trastuzumab. A total of 14,546 patients from 13 RCTs were included in the analysis; 9 RCTs used an adjuvant setting and 4 RCTs used a neoadjuvant setting. Analysis of RCTs with an adjuvant setting demonstrated that treatment with trastuzumab and chemotherapy in patients with HER-2 positive BC, in comparison with patients receiving chemotherapy alone, improved disease-free survival, overall survival and overall response. However, a higher incidence of neutropenia (P<0.0001), leukopenia (P<0.0001), diarrhea (P=0.002), skin/nail change (P=0.02), left ventricular ejection fraction reduction (P=0.007) and congestive heart failure (P<0.00001) was observed. Notably, the incidence of mortality and cardiac toxicity following concurrent and weekly use of trastuzumab was significantly lower compared to treatment with trastuzumab sequentially and every 3 weeks, respectively. Additionally, trastuzumab improved the pathologic complete response with no additional toxicity in the neoadjuvant setting. The present meta-analysis summarizes that trastuzumab is efficacious in patients with HER-2 positive BC in adjuvant and neoadjuvant settings. Thus, concurrent and weekly administration of trastuzumab is preferable to treatment with trastuzumab sequentially and every 3 weeks. These findings should be considered when using trastuzumab in future clinical practice.

Impact of prior anthracycline or taxane use on eribulin effectiveness as first-line treatment for metastatic breast cancer: results from two phase 2, multicenter, single-arm studies

Eribulin mesylate has efficacy in patients who have received ≥2 prior chemotherapies for metastatic breast cancer (MBC) including an anthracycline and taxane. Phase 2 trials showed clinical activity and acceptable tolerability of first-line eribulin (HER2− MBC; Study 206) and eribulin plus trastuzumab (HER2+ MBC; Study 208). Prespecified analyses evaluated efficacy by prior anthracycline and/or taxane use. Patients received eribulin mesylate (1.4 mg/m² IV; Days 1 and 8) and, in Study 208, trastuzumab (8 mg/kg IV/Cycle 1, then 6 mg/kg; Day 1) in 21-day cycles. Endpoints included objective response rate (ORR), progression-free survival (PFS), and tolerability. In Study 206 (N = 56), 48 % of patients had received prior anthracycline, 46 % prior taxane, 36 % prior anthracycline and taxane, and 41 % were chemotherapy-naïve. In Study 208 (N = 52), these percentages were 21, 44, 17, and 52 %, respectively. In Study 206, ORR and median PFS were similar for anthracycline-pretreated (25.9 %, 5.8 months), taxane-pretreated (26.9 %, 5.8 months), anthracycline- and taxane-pretreated (25.0 %, 6.7 months), and anthracycline/taxane-naïve patients (30.4 %, 7.6 months). In Study 208, ORR/median PFS were 63.6 %/6.7 months among anthracycline-pretreated patients, 56.5 %/6.8 months among taxane-pretreated patients, 55.6 %/5.9 months among anthracycline- and taxane-pretreated patients, and 81.5 %/13.1 months among anthracycline/taxane-naïve patients. Tolerability was generally similar among subgroups. In these studies, first-line eribulin in HER2− MBC and eribulin/trastuzumab in HER2+ MBC was effective with acceptable tolerability, regardless of prior anthracycline/taxane treatment. Prior chemotherapy was associated with lower ORR and shorter PFS with eribulin/trastuzumab in HER2+ MBC but not with eribulin in HER2− MBC.

Balancing activity and tolerability of neoadjuvant paclitaxel- and docetaxel-based chemotherapy for HER2-positive early stage breast cancer: sensitivity analysis of randomized trials

Paclitaxel and docetaxel represent the most adopted taxanes in the neoadjuvant treatment of HER2-positive breast cancer. Questions still remain with regard to their difference in terms of activity and tolerability. Events for pathological complete response (pCR), severe and febrile neutropenia (FN), and severe neurotoxicity were pooled by adopting a fixed- and random-effect model. A sensitivity analysis to test for the interaction between paclitaxel and docetaxel was accomplished. Absolute differences with 95% confidence intervals (CIs) and the number of patients needed to treat/harm (NNT/NNH) were calculated to derive the Likelihood of being Helped or Harmed (LHH). Data from 15 trials (3601 patients) were included. Paclitaxel significantly increases pCR rate by 6.8% in comparison with docetaxel (43.4%, 95% CI 41.1-45.7% versus 36.6%, 95% CI 34.3-39.0%, p=0.0001), regardless of the chemotherapy backbone, with an absolute difference of 9% and 9.2% for anthracycline-based or free-regimens. Paclitaxel significantly improves pCR versus docetaxel with a single HER2-inhibition by 6.7% (p=0.0012), with no difference if combined with a dual HER2-inhibition. Severe neutropenia and FN are significantly lower with paclitaxel, with an absolute difference of 32.4% (p<0.0001) and 2.5% (p=0.0059), respectively. Conversely, severe neurotoxicity is slightly higher with paclitaxel (3%, p=0.0001). The LHH ratio calculated for pCR and severe neutropenia is 2.0 and 0.7 for paclitaxel and docetaxel. Although the activity of neoadjuvant paclitaxel and docetaxel HER2-positive breast cancer is considered similar, the slight advantage in pCR, the significantly lower neutropenia and FN, do favor paclitaxel (in the weekly fashion) over docetaxel, despite the slightly worst neurotoxicity.

HER2-directed therapy: current treatment options for HER2-positive breast cancer

Over the past decade, the management of HER2-positive breast cancer has evolved dramatically. In addition to advances in screening, genetic testing, imaging, surgical and radiation techniques, innovations in medical therapy including widespread use of HER2-directed therapy in early and advanced breast cancer have revolutionized breast cancer care and changed the natural history of HER2-positive breast cancer. A substantial number of HER2-targeted agents are being developed including monoclonal antibodies, small molecule inhibitors, and antibody drug conjugates. Trastuzumab is the prototype HER2-directed therapy that was introduced in the late 1990s for the management of metastatic breast cancer and later showed efficacy in early stage disease. Despite the practice changing impact of trastuzumab and improvement in outcomes of women with HER2-positive breast cancer resistance to trrastuzumab is a major clinical issue, occurring in both early stage and advanced disease, and new treatment strategies are clearly required. Combining HER2-targeted agents and dual HER2 blockade has been successful in early and advanced breast cancer. Furthermore, selected delivery of potent chemotherapeutic agent coupled with HER2 inhibition promises new treatment options. This review is focused on current HER2-directed treatments for women with HER2-positive breast cancer including monoclonal antibodies, small molecule inhibitors, and antibody drug conjugates.

Efficacy and Safety of HER2-Targeted Agents for Breast Cancer with HER2-Overexpression: A Network Meta-Analysis

BACKGROUND

Clinical trials of human epidermal growth factor receptor 2 (HER2)-targeted agents added to standard treatment have been efficacious for HER2-positive (HER2+) advanced breast cancer. To our knowledge, no meta-analysis has evaluated HER2-targeted therapy including trastuzumab emtansine (T-DM1) and pertuzumab for HER2-positive breast caner and ranked the targeted treatments. We performed a network meta-analysis of both direct and indirect comparisons to evaluate the effect of adding HER2-targeted agents to standard treatment and examined side effects.

METHODS

We performed a Bayesian-framework network meta-analysis of randomized controlled trials to compare 6 HER2-targeted treatment regimens and 1 naïve standard treatment (NST, without any-targeted drugs) in targeted treatment of HER2+ breast cancer in adults. These treatment regimens were T-DM1, LC (lapatinib), HC (trastuzumab), PEC (pertuzumab), LHC (lapatinib and trastuzumab), and PEHC (pertuzumab and trastuzumab). The main outcomes were overall survival and response rates. We also examined side effects of rash, LVEF (left ventricular ejection fraction), fatigue, and gastrointestinal disorders, and performed subgroup analysis for the different treatment regimens in metastatic or advanced breast cancer.

RESULTS

We identified 25 articles of 21 trials, with data for 11,276 participants. T-DM1 and PEHC were more efficient drug regimens with regard to overall survival as compared with LHC, LC, HC and PEC. The incidence of treatment-related rash occurs more frequently in the patients who received LC treatment regimen than PEHC and T-DM1 and HC. In subgroup analysis, T-DM1 was associated with increased overall survival as compared with LC and HC. PEHC was associated with increased overall response as compared with LC, HC, and NST.

CONCLUSIONS

Overall, the regimen of T-DM1 as well as pertuzumab in combination with trastuzumab and docetaxel is efficacious with fewer side effects as compared with other regimens, especially for advanced HER2+ breast cancer.

IMPACT

This study suggests that both T-DM1 and PEHC therapy are potentially and equally useful treatments for HER2+ breast cancer.

Effectiveness of targeted therapy in patients with previously untreated metastatic breast cancer: a systematic review and meta-analysis

Breast cancer is the most common cancer and the most frequent cause of death in women. Targeted therapies offer a possibility of effective and individualized therapy based on the molecular profile of the tumor. The aim of this systematic review was to evaluate the efficacy and safety of targeted agents added to chemotherapy or endocrine therapy in patients with previously untreated metastatic breast cancer (MBC) depending on their human epidermal growth factor receptor 2 (HER2) and hormone receptor (HR) status (positive or negative). The systematic literature search was performed in PubMed, EMBASE, and the Cochrane Library to identify randomized controlled trials (RCTs). Thirteen trials were included. The addition of trastuzumab, pertuzumab, bevacizumab, or lapatinib to chemotherapy significantly (P < .05) improved objective response rate (ORR), time to failure (TTF), and overall survival (OS) in patients with HER2-positive (HER2(+)) disease. Trastuzumab or lapatinib combined with endocrine therapy significantly (P < .05) improved ORR, time to progression (TTP), and progression-free survival (PFS) in patients with HER2(+) and HR(+) disease. In patients with HER2-negative (HER2(-)) cancer, bevacizumab or lapatinib added to chemotherapy significantly (P < .05), improved ORR but did not prolong PFS and OS (P > .05). In patients with HER2(-) and HR(-) disease, trastuzumab combined with chemotherapy did not significantly improve (P > .05) ORR or PFS. Targeted therapies also increased the overall risk of adverse events. So far, there is a lack of published results for everolimus and trastuzumab emtansine trials in patients with previously untreated MBC. The addition of targeted therapy to chemotherapy or endocrine therapy using HER2 and HR status significantly improved ORR, PFS, and OS in patients with previously untreated MBC.

The Long-HER study: clinical and molecular analysis of patients with HER2+ advanced breast cancer who become long-term survivors with trastuzumab-based therapy

Background

Trastuzumab improves survival outcomes in patients with HER2+ metastatic breast cancer. The Long-Her study was designed to identify clinical and molecular markers that could differentiate long-term survivors from patients having early progression after trastuzumab treatment.

Methods

Data were collected from women with HER2-positive metastatic breast cancer treated with trastuzumab that experienced a response or stable disease during at least 3 years. Patients having a progression in the first year of therapy with trastuzumab were used as a control. Genes related with trastuzumab resistance were identified and investigated for network and gene functional interrelation. Models predicting poor response to trastuzumab were constructed and evaluated. Finally, a mutational status analysis of selected genes was performed in HER2 positive breast cancer samples.

Results

103 patients were registered in the Long-HER study, of whom 71 had obtained a durable complete response. Median age was 58 years. Metastatic disease was diagnosed after a median of 24.7 months since primary diagnosis. Metastases were present in the liver (25%), lungs (25%), bones (23%) and soft tissues (23%), with 20% of patients having multiple locations of metastases. Median duration of response was 55 months. The molecular analysis included 35 patients from the group with complete response and 18 patients in a control poor-response group. Absence of trastuzumab as part of adjuvant therapy was the only clinical factor associated with long-term survival. Gene ontology analysis demonstrated that PI3K pathway was associated with poor response to trastuzumab-based therapy: tumours in the control group usually had four or five alterations in this pathway, whereas tumours in the Long-HER group had two alterations at most.

Conclusions

Trastuzumab may provide a substantial long-term survival benefit in a selected group of patients. Whole genome expression analysis comparing long-term survivors vs. a control group predicted early progression after trastuzumab-based therapy. Multiple alterations in genes related to the PI3K-mTOR pathway seem to be required to confer resistance to this therapy.

Strategies for modern biomarker and drug development in oncology

Technological advancements in the molecular characterization of cancers have enabled researchers to identify an increasing number of key molecular drivers of cancer progression. These discoveries have led to multiple novel anticancer therapeutics, and clinical benefit in selected patient populations. Despite this, the identification of clinically relevant predictive biomarkers of response continues to lag behind. In this review, we discuss strategies for the molecular characterization of cancers and the importance of biomarkers for the development of novel antitumor therapeutics. We also review critical successes and failures in oncology, and detail the lessons learnt, which may aid in the acceleration of anticancer drug development and biomarker discovery.

Paclitaxel and trastuzumab for breast cancer

The complexity of cancer chemotherapy requires pharmacists be familiar with the complicated regimens and highly toxic agents used. This column reviews various issues related to preparation, dispensing, and administration of antineoplastic therapy, and the agents, both commercially available and investigational, used to treat malignant diseases. Questions or suggestions for topics should be addressed to Dominic A. Solimando, Jr., President, Oncology Pharmacy Services, Inc., 4201 Wilson Blvd #110-545, Arlington, VA 22203, e-mail: OncRxSvc@comcast.net; or J. Aubrey Waddell, Professor, University of Tennessee College of Pharmacy; Oncology Pharmacist, Pharmacy Department, Blount Memorial Hospital, 907 E. Lamar Alexander Parkway, Maryville, TN 37804, e-mail: waddfour@charter.net.

Trastuzumab-containing regimens for metastatic breast cancer

BACKGROUND

Patients with breast cancer are classified as having cells that over-express the human epidermal growth factor receptor 2 (known as HER2-positive) or not (HER2-negative). Typically, patients with HER2-positive disease have a worse prognosis. Trastuzumab is a selective treatment that targets the HER2 pathway. The available evidence supporting trastuzumab regimens mostly relies upon surrogate endpoints and, although the efficacy results seem to support its use, other uncertainties have been raised about its net benefit in relation to transient cardiac toxicity and a long-term increased risk of metastasis to the central nervous system.

OBJECTIVES

To assess the evidence on the efficacy and safety of therapy with trastuzumab (overall) and in relation to the type of co-administered regimen and the line of treatment, i.e. first-line or beyond progression, in women with HER2-positive metastatic breast cancer.

SEARCH METHODS

We searched the Cochrane Breast Cancer Group's (CBCG) Specialised Register and used the search strategy developed by the CBCG to search for randomised controlled trials (RCTs) in CENTRAL (2013, Issue 1), MEDLINE, EMBASE, BIOSIS, the WHO International Clinical Trials Registry Platform (ICTRP) search portal and ClinicalTrials.gov (up to 17 January 2013).

SELECTION CRITERIA

RCTs comparing the efficacy and safety of trastuzumab alone or in combination with chemotherapy, hormonal therapy or targeted agents in women with HER2-positive metastatic breast cancer.

DATA COLLECTION AND ANALYSIS

We collected data from published trials. We used hazard ratios (HRs) for time-to-event outcomes and risk ratio (RRs) for binary outcomes. Subgroup analyses included type of regimen (taxane-containing, anthracycline-containing, aromatase inhibitor-containing or other) and treatment line (first-line, beyond progression).

MAIN RESULTS

The review found seven trials, involving 1497 patients, which met the criteria to be included. The trials were generally of moderate methodological quality; two studies have not published their results on overall survival so the presence of selective outcome reporting bias cannot be ruled out. None of the studies used blinding to treatment allocation, though this is unlikely to have biased the results for overall survival. Studies varied in terms of co-administered regimen and in terms of treatment line. In four studies, trastuzumab was administered with a chemotherapy, such as a taxane-containing, anthracycline-containing or capecitabine-containing regimen. Two studies considered postmenopausal women and administered trastuzumab with hormone-blocking medications, such as an aromatase inhibitor. One study administered trastuzumab in addition to lapatinib. Five studies out of seven included women treated with trastuzumab administered until progression as first-line treatment and two studies considered trastuzumab beyond progression. The combined HRs for overall survival and progression-free survival favoured the trastuzumab-containing regimens (HR 0.82, 95% confidence interval (CI) 0.71 to 0.94, P = 0.004; and HR 0.61, 95% CI 0.54 to 0.70, P < 0.00001, respectively; moderate-quality evidence). Trastuzumab increased the risk of congestive heart failure (RR 3.49, 90% CI 1.88 to 6.47, P = 0.0009; moderate-quality evidence) and left ventricular ejection fraction (LVEF) decline (RR 2.65, 90% CI 1.48 to 4.74, P = 0.006). For haematological toxicities, such as neutropenic fever and anaemia, there was no clear evidence that risks differed between groups, while trastuzumab seemed to raise the risk of neutropenia. The overall survival improvement was maintained when considering patients treated as first-line or patients receiving taxane-based regimens. The progression-free survival improvement was maintained when considering patients receiving taxane-based regimens, and patients treated as first-line or subsequent lines. Few data were collected on central nervous system progression. Similarly, few studies reported on quality of life and treatment-related deaths.

AUTHORS' CONCLUSIONS

Trastuzumab improved overall survival and progression-free survival in HER2-positive women with metastatic breast cancer, but it also increased the risk of cardiac toxicities, such as congestive heart failure and LVEF decline. The available subgroup analyses are limited by the small number of studies. Studies that administered trastuzumab as first-line treatment, or along with a taxane-based regimen, improved mortality outcomes. The evidence to support the use of trastuzumab beyond progression is limited. The recruitment in three out of seven studies was stopped early and in three trials more than 50% of patients in the control groups were permitted to switch to the trastuzumab arms at progression, making it more difficult to understand the real net benefit of trastuzumab.Trastuzumab is generally used for women with HER2-positive early breast cancer in clinical practice, while women enrolled in most of the trials in the metastatic setting were naive to trastuzumab. The effectiveness of trastuzumab for women relapsing after adjuvant trastuzumab is therefore still an open issue, although it is likely that the majority are being offered it again.