Mitigation of paclitaxel-induced peripheral neuropathy in breast cancer patients using limb-cooling apparatus: a study protocol for a randomized controlled trial

Background

Chemotherapy-induced peripheral neuropathy (CIPN) is one of the most common adverse events that can significantly impair the quality of life of patients. Although limb cooling may be beneficial for preventing CIPN, logistical challenges exist in ensuring consistent efficacy and safety. The purpose of this randomized controlled trial is to validate whether limb cooling with strict temperature control can reduce CIPN in patients with breast cancer receiving weekly paclitaxel as a perioperative treatment.

Methods

This study is a multicenter, double-blinded, randomized controlled trial. We plan to enroll patients with breast cancer who are scheduled to receive 12 weekly doses of paclitaxel (60 min 80 mg/m² intravenous infusion) as perioperative chemotherapy. Patients will be randomly divided into the intervention or control groups and undergo limb cooling therapy maintained at a constant temperature of 13°C and 25°C, respectively. The primary endpoint is the proportion of patients who report Patient Neurotoxicity Questionnaire (PNQ) ≥ D in their limbs by the end of the study treatment or at the time of discontinuation.

Discussion

The results of this trial will contribute to the establishment of new evidence for limb cooling therapy in the mitigation of CIPN and present a safe and stable cooling device that may be suitable for use in the clinic.

Clinical trial registration

https://jrct.niph.go.jp/en-latest-detail/jRCT2032210115, identifier jRCT2032210115.

Adjuvant olaparib in the subset of patients from Japan with BRCA1- or BRCA2-mutated high-risk early breast cancer from the phase 3 OlympiA trial

BACKGROUND

The efficacy and safety of olaparib compared with placebo in the subset of patients from Japan in the phase 3 OlympiA trial (NCT02032823) are reported here and contextualized with reference to the global OlympiA population.

METHODS

Patients with germline BRCA1 and/or BRCA2 pathogenic variants and HER2-negative, high-risk early breast cancer who had received neoadjuvant or adjuvant chemotherapy and completed local treatment were eligible. Patients were randomized 1:1 to receive olaparib or placebo for 1 year.

PRIMARY ENDPOINT

invasive disease-free survival (IDFS). Secondary endpoints: distant disease-free survival (DDFS), overall survival (OS), and safety. Data are reported from the first pre-specified interim analysis (data cut-off [DCO] March 27, 2020) and the second, event driven, pre-specified interim analysis of OS (DCO July 12, 2021) in patients from Japan.

RESULTS

140 patients were randomized in Japan (olaparib, n = 64; placebo, n = 76). At the first pre-specified interim analysis (median follow-up: 2.9 years), hazard ratios (HRs) for adjuvant olaparib compared with placebo were 0.5 for IDFS (95% confidence interval [CI] 0.18-1.24) and 0.41 for DDFS (95% CI 0.11-1.16). At the second pre-specified interim analysis of OS, three deaths occurred in the olaparib group versus six deaths in the placebo group (HR, 0.62 [95% CI 0.13-2.36]). Findings were consistent with those for the global population. No new safety signals were observed.

CONCLUSIONS

While this analysis in a Japanese subset of patients was not powered to detect population-related treatment differences, efficacy and safety analysis results were consistent with the global OlympiA population, suggesting the findings from the global study are generalizable to clinical practice in Japan.

Trastuzumab deruxtecan versus treatment of physician's choice in patients with HER2-positive metastatic breast cancer (DESTINY-Breast02): a randomised, open-label, multicentre, phase 3 trial

BACKGROUND

In the single-arm, phase 2 DESTINY-Breast01 trial, trastuzumab deruxtecan showed robust activity in patients with HER2-positive metastatic breast cancer who were refractory or resistant to trastuzumab emtansine; a population with scarce effective treatments. In DESTINY-Breast02, we aimed to compare the efficacy and safety of trastuzumab deruxtecan with treatment of physician's choice in this patient population.

METHODS

This randomised, open-label, multicentre, phase 3 trial was conducted at 227 sites (hospitals, university hospitals, clinics, community centres, and private oncology centres) in North America, Europe, Asia, Australia, Brazil, Israel, and Türkiye. Eligible patients were aged 18 years or older, had unresectable or HER2-positive metastatic breast cancer, previously received trastuzumab emtansine, disease progression, an Eastern Cooperative Oncology Group performance status of 0 or 1, and adequate renal and hepatic function. Patients were randomly assigned (2:1) to receive trastuzumab deruxtecan (intravenously at 5·4 mg/kg once every 3 weeks) or treatment of physician's choice using block randomisation. Treatment of physician's choice was either capecitabine (1250 mg/m2; orally twice per day on days 1-14) plus trastuzumab (8 mg/kg intravenously on day 1 then 6 mg/kg once per day) or capecitabine (1000 mg/m2) plus lapatinib (1250 mg orally once per day on days 1-21), with a 21-day schedule. The primary endpoint was progression-free survival based on blinded independent central review in the full analysis set. This study is registered with ClinicalTrials.gov, NCT03523585.

FINDINGS

Between Sept 6, 2018, and Dec 31, 2020, 608 patients were randomly assigned to receive trastuzumab deruxtecan (n=406; two did not receive treatment) or treatment of physician's choice (n=202; seven did not receive treatment). 608 (100%) patients were included in the full analysis set. The median age was 54·2 years (IQR 45·5-63·4) in the trastuzumab deruxtecan group and 54·7 years (48·0-63·0) in the treatment of physician's choice group. 384 (63%) patients were White, 603 (99%) were female, and five (<1%) were male. The median follow-up was 21·5 months (IQR 15·2-28·4) in the trastuzumab deruxtecan group and 18·6 months (8·8-26·0) in the treatment of physician's choice group. Median progression-free survival by blinded independent central review was 17·8 months (95% CI 14·3-20·8) in the trastuzumab deruxtecan group versus 6·9 months (5·5-8·4) in the treatment of physician's choice group (HR 0·36 [0·28-0·45]; p<0·0001). The most common treatment-emergent adverse events were nausea (293 [73%] of 404 with trastuzumab deruxtecan vs 73 [37%] of 195 with treatment of physician's choice), vomiting (152 [38%] vs 25 [13%]), alopecia (150 [37%] vs eight [4%]), fatigue (147 [36%] vs 52 [27%]), diarrhoea (109 [27%] vs 105 [54%]), and palmar-plantar erythrodysaesthesia (seven [2%] vs 100 [51%]). Grade 3 or higher treatment-emergent adverse events occurred in 213 (53%) patients receiving trastuzumab deruxtecan versus 86 (44%) receiving treatment of physician's choice; whereas drug-related interstitial lung disease occurred in 42 (10%; including two grade 5 death events) versus one (<1%).

INTERPRETATION

DESTINY-Breast02 shows the favourable benefit-risk profile of trastuzumab deruxtecan in patients with HER2 positive metastatic breast cancer, as previously reported in DESTINY-Breast01, and is the first randomised study to show that one antibody-drug conjugate can overcome resistance to a previous one.

FUNDING

Daiichi Sankyo and AstraZeneca.

Real-world treatment patterns and outcomes of abemaciclib for the treatment of HR + , HER2- metastatic breast cancer patients in Japan

INTRODUCTION

This study described, in routine clinical practice in Japan, the patient characteristics, treatment patterns, and outcomes of female patients with HR + /HER2- metastatic breast cancer (MBC) who started abemaciclib treatment.

METHODS

Clinical charts were reviewed for patients starting abemaciclib in 12/2018-08/2021 with a minimum of 3 months follow-up data post-abemaciclib initiation regardless of abemaciclib discontinuation. Patient characteristics, treatment patterns, and tumor response were descriptively summarized. Kaplan-Meier curves estimated progression-free survival (PFS).

RESULTS

200 patients from 14 institutions were included. At abemaciclib initiation, median age was 59 years, and the Eastern Cooperative Oncology Group performance status score was 0/1/2 for 102/68/5 patients (58.3/38.9/2.9%), respectively. Most had an abemaciclib starting dose of 150 mg (92.5%). The percentage of patients receiving abemaciclib as 1st, 2nd, or 3rd line treatment was 31.5%, 25.8%, and 25.2%, respectively. The most frequent endocrine therapy drugs used with abemaciclib were fulvestrant (59%) and aromatase inhibitors (40%). Evaluation of tumor response was available for 171 patients, 30.4% of whom had complete/partial response. Median PFS was 13.0 months (95% CI 10.1-15.8 months).

CONCLUSIONS

In a routine clinical practice setting in Japan, patients with HR + , HER2- MBC appear to benefit from abemaciclib treatment in terms of treatment response and median PFS, with the results broadly reflecting the evidence demonstrated in clinical trials.

Multicentre, randomised, double-blind, placebo-controlled phase II study of prophylactic olanzapine for patients with metastatic breast cancer receiving T-DXd treatment: protocol for the ERICA study (WJOG14320B)

INTRODUCTION

The antibody-drug conjugate trastuzumab deruxtecan (T-DXd) has led to a change in the clinical management of breast cancer. Nausea and vomiting are the most common adverse events of T-DXd, which cannot be completely alleviated by standard prophylactic regimens. Olanzapine is particularly effective in preventing delayed nausea caused by chemotherapy. In this study, we will evaluate the efficacy of olanzapine in managing persistent nausea and vomiting during T-DXd treatment.

METHODS AND ANALYSIS

The ERICA study is a multicentre, placebo-controlled, double-blind, randomised phase II study with the aim to evaluate the antiemetic effects of the prophylactic olanzapine (5 mg orally, on days 1-6) or placebo combined with a 1,5-hydroxytryptamine-3 (5-HT₃)-receptor antagonist and dexamethasone in patients with human epidermal growth factor receptor 2-positive metastatic breast cancer undergoing T-DXd treatment. For a period of 22 days from the day of T-DXd treatment, patients will document their experience in an electronic symptom diary daily during observational periods. The primary endpoint is the complete response rate, defined as no vomiting and no rescue medications during the 'delayed phase' of 24-120 hours post-T-DXd administration. In addition, we define 120-504 hour as the 'persistent phase' and 0-504 hours as the 'overall phase' for secondary endpoint analysis. We have estimated that a total sample size of at least 156 patients is needed to allow a power of 80% at a one-sided significance level of 20% in this study. The target sample size is set to 166 to account for possible case exclusions.

ETHICS AND DISSEMINATION

The study protocol is approved by the West Japan Oncology Group protocol review committee and the SHOWA University Clinical Research Review Board. The study results will be presented at international conferences and published in a peer-reviewed journal.

TRIAL REGISTRATION NUMBER

jRCTs031210410.

Pembrolizumab plus chemotherapy in Japanese patients with triple-negative breast cancer: Results from KEYNOTE-355

Pembrolizumab plus chemotherapy improved progression-free survival (PFS) and overall survival (OS) compared with placebo plus chemotherapy in patients with previously untreated locally recurrent inoperable or metastatic triple-negative breast cancer with tumor programmed cell death ligand 1 (PD-L1) combined positive score (CPS) ≥10 in the global, phase 3, randomized controlled trial KEYNOTE-355. We report results for patients enrolled in Japan. Patients were randomized 2:1 to pembrolizumab 200 mg or placebo Q3W for 35 cycles plus chemotherapy (nab-paclitaxel, paclitaxel, or gemcitabine-carboplatin). Primary endpoints were PFS per RECIST version 1.1 by blinded independent central review and OS in patients with PD-L1 CPS ≥10, PD-L1 CPS ≥1, and the intention-to-treat (ITT) population. No alpha was assigned to this exploratory analysis. Eighty-seven patients were randomized in Japan (pembrolizumab plus chemotherapy, n = 61; placebo plus chemotherapy, n = 26), 66 (76%) had PD-L1 CPS ≥1, and 28 (32%) had PD-L1 CPS ≥10. Median time from randomization to data cutoff (June 15, 2021) was 44.7 (range, 37.2-52.9) months in the ITT population. Hazard ratios (HRs; 95% CI) for OS were 0.36 (0.14-0.89), 0.52 (0.30-0.91), and 0.46 (0.28-0.77) in the PD-L1 CPS ≥10, PD-L1 CPS ≥1, and ITT populations, respectively. HRs (95% CI) for PFS were 0.52 (0.20-1.34), 0.61 (0.35-1.06), and 0.64 (0.39-1.05). Grade 3 or 4 treatment-related adverse events occurred in 85% of patients in each group (no grade 5 events). Consistent with the global population, pembrolizumab plus chemotherapy tended to show improvements in OS and PFS with manageable toxicity versus placebo plus chemotherapy in Japanese patients and supports this combination in this setting.

Retrospective study on the effectiveness of medroxyprogesterone acetate in the treatment of ER-positive/HER2-negative post-menopausal advanced breast cancer: an additional analysis of the JBCRG-C06 Safari study

BACKGROUND

Only old evidence exists to back up the use of medroxyprogesterone acetate. Therefore, this study aimed to explore the factors that influence the time to treatment failure of medroxyprogesterone acetate in real-world settings as late-line treatment.

METHODS

This was a cohort study that used the database of the Safari study on oestrogen receptor-positive post-menopausal advanced breast cancer (UMIN000015168). We created Kaplan-Meier curves for time to treatment failure with medroxyprogesterone acetate. Further, univariate and multivariate analyses were performed using a Cox hazard model of the clinicopathological factors involved in the time to treatment failure of medroxyprogesterone acetate.

RESULTS

From the 1031 patients in the Safari study, 279 patients were selected as the population for the analysis of effectiveness of medroxyprogesterone acetate monotherapy. In the analysis of medroxyprogesterone acetate by treatment line, the median time to treatment failure was 3.0 months for third-line treatment and 4.1 months for fourth and subsequent treatment lines. In cases where medroxyprogesterone acetate was used as a third-line or later endocrine treatment, multivariate analysis showed that the length of the disease-free interval was correlated with the length of time to treatment failure of medroxyprogesterone acetate (P = 0.004). With medroxyprogesterone acetate monotherapy as the fourth-line or later treatment, 20% of the patients achieved a time to treatment failure of 12 months or longer.

CONCLUSION

In actual clinical practice, patients treated with medroxyprogesterone acetate alone as the fourth or subsequent treatment lines showed a time to treatment failure of 4 months, suggesting that there is merit in using medroxyprogesterone acetate even in late treatment lines, especially in patients with long disease-free interval and those who are difficult to treat using other antineoplastic agents.

Abstract P2-03-15: Retrospective study using database for the effectiveness of medroxyprogesterone acetate in patients with ER-positive/HER2-negative postmenopausal advanced breast cancer: An additional analysis of the JBCRG-C06 Safari study

Background: Only old evidence exist to back up the use of medroxyprogesterone acetate (MPA) in endocrine therapy. Therefore, this study aimed to explore the factors that influence the time to treatment failure (TTF) of MPA in real world settings as late-line treatment following aromatase inhibitors and fulvestrant.

Methods: This was a cohort study that used the database of the Safari study, on estrogen receptor-positive (ER+) post-menopausal advanced breast cancer previously treated with fulvestrant (UMIN000015168). We created Kaplan-Meier curves for TTF treated with MPA. Further, univariate and multivariate analyses were performed using a Cox hazard model of the clinicopathological factors involved in the TTF of MPA.

Results: Fist, we made Kaplan-Meier curves by treatment line for MPA in TTF analysis population 1 (n = 244), excluding HER2+ and HER2 with unknown status. The median TTF for MPA was 8.2 months (95% CI 5.1–14.9) for first- and second-line treatments, 3.0 months (95% CI 2.5–3.9) for third-line treatment, and 4.1 months (95% CI 3.5–5.0) for fourth or later treatment lines. The first- and second-line treatments had significantly longer TTF than the third-line treatment (P &lt; 0.001) and fourth-line or later treatments (P &lt; 0.001). No difference in TTF was observed between the third and fourth or later treatment lines. Similar results were obtained in the analysis population 2 (n = 203) for TTF, excluding cases in which MPA was considered to have been used in palliative care. The median TTF for MPA was 7.9 months (95% CI, 5.1-16.0) for first- and second-line treatments, 3.0 months (95% CI 2.8–4.6) for third-line treatment, and 4.3 months (95% CI 3.7–5.6) for fourth or later treatment lines. The first- and second-line treatments had significantly longer TTF than the third-line treatment (P &lt; 0.001) and the fourth-line or later treatments (P &lt; 0.001). No difference in TTF was observed between the third and fourth or later treatment lines. Second, Table 1 shows the clinicopathological factors involved in the TTF of MPA. In univariate analysis, long DFI (≥ 6 years), small nuclear or histological grade, and the presence of visceral metastases correlated with significantly long TTF (P &lt; 0.05). Whereas PgR, adjuvant chemotherapy, and adjuvant endocrine therapy did not affect the TTF of patients treated with MPA. However, in the multivariate regression analysis, only longer DFI (≥ 6 years) was correlated with a significantly longer TTF. Third, we compared the clinicopathologic factors in the groups that received MPA as the fourth or later treatment lines and achieved a TTF of more than 1 year with those that did not. There were no characteristic clinicopathological factors distinct between the two groups.

Conclusion: In actual clinical practice, patients treated with MPA alone as the fourth or subsequent treatment lines showed a TTF of 4 months, suggesting that there is merit in using MPA even in late treatment lines, especially in patients with long DFI and those who are difficult to treat with other antineoplastic agents.

Table 1. Univariate and Multivariate analyses to investigate association between clinicopathological factors and TTF of MPA (n=170)

Citation Format: Kaho Utsunomiya, Hidetoshi Kawaguchi, Yutaka Yamamoto, Shigehira Saji, Norikazu Masuda, Takahiro Nakayama, Kenjiro Aogi, Keisei Anan, Shoichiro Ohtani, Nobuaki Sato, Toshimi Takano, Eriko Tokunaga, Seigo Nakamura, Yoshie Hasegawa, Masaya Hattori, Tomomi Fujisawa, Satoshi Morita, Miki Yamaguchi, Toshinari Yamashita, Daisuke Yotsumoto, Masakazu Toi, Shinji Ohno. Retrospective study using database for the effectiveness of medroxyprogesterone acetate in patients with ER-positive/HER2-negative postmenopausal advanced breast cancer: An additional analysis of the JBCRG-C06 Safari study [abstract]. In: Proceedings of the 2022 San Antonio Breast Cancer Symposium; 2022 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2023;83(5 Suppl):Abstract nr P2-03-15.

Abstract P1-12-08: Biomarker analysis of hepatotoxicity in a Phase II study of nivolumab, abemaciclib and endocrine therapy in patients with HR-positive, HER2-negative breast cancer: WJOG11418BTR NEWFLAME_TR

Background Previously, we reported the clinical outcomes of the combination of anti-PD-1 Ab, cyclin-dependent kinase 4/6 inhibitors, and endocrine therapy (ET) in patients with ER positive/HER2 negative advanced breast cancer in SABCS2020; biomarker analysis has been performed to provide insight into the hepatotoxicy frequently observed in the study. Methods Subjects received 240 mg nivolumab IV on days 1 and 15, 150 mg abemaciclib PO twice daily, and either 500 mg fulvestrant (FUL) on days 1, 15, 29, and every 4 weeks thereafter (FUL cohort) or 2.5 mg letrozole (LET) once daily (LET cohort). The primary endpoint was objective response rate and secondary endpoints included toxicity evaluated in the CTCAE along with an exploratory endpoint as related to the biomarker analysis. Archival tumor tissues were collected before study entry and blood and stool samples were collected at baseline and on cycle3 day1. Tumor tissues were subjected to IHC analysis and RNA sequencing followed by subtyping using NGS. High throughput cytokine analysis using ELISA-based assay were performed with serum samples and cell sorting analysis of PBMC was performed with FACS. Results From June 2019 to December 2019, 17 subjects were enrolled (FUL cohort [n = 12], LET cohort [n = 5]). The study was prematurely closed due to safety concerns such as hepatotoxicity and interstitial lung disease. AEs ≥ Grade 3 were observed in 91.7% and 100% of patients in the FUL and LET cohorts, respectively. The most frequent AEs ≥ Grade 3 were elevated liver function tests (LFT; FUL cohort: 50.0%, LET cohort: 60.0%). Serum cytokine analysis from the subjects with severe hepatotoxicity indicated cytokine storm with elevations of sCD30/TNFRSF8, IL-11, -34, Pentraxin-3, sTNF-R1, -R2, TSLP, which was supported by the findings of reduction of effector regulatory T cells in PBMC. IHC study in liver biopsy from three subjects with the toxicity revealed infiltration of CD8+ T cells and FOXP3+ T reg into the liver, suggesting the immune related liver injury upon the treatment with nivolumab and abemaciclib. HLA typing was performed in the 17 patients but no association between HLA type and ILD or hepatotoxicity were observed. Conclusions The frequent and severe immune related hepatotoxicity induced by the combination of anti-DD-1 and CDK 4/6 inhibitors might have been an immune-boosting therapy as suggested in the preclinical studies. This study was supported by the Ono Pharmaceutical Co., LTD. The registration number of the study is UMIN000036970.

Citation Format: Junji Tsurutani, Jun Masuda, Norikazu Masuda, Yuko Tanabe, Tsutomu Iwasa, Masato Takahashi, Manabu Futamura, Koji Matsumoto, Kenjiro Aogi, Hiroji Iwata, Mari Hosonaga, Toru Mukohara, Kiyoshi Yoshimura, Chiyo K. Imamura, Sakiko Miura, Toshiko Yamochi, Kenichi Yoshimura, Toshimi Takano, Hidetaka Kawabata. Biomarker analysis of hepatotoxicity in a Phase II study of nivolumab, abemaciclib and endocrine therapy in patients with HR-positive, HER2-negative breast cancer: WJOG11418BTR NEWFLAME_TR [abstract]. In: Proceedings of the 2022 San Antonio Breast Cancer Symposium; 2022 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2023;83(5 Suppl):Abstract nr P1-12-08.

Abstract P5-02-42: Soluble CD163 may be a predictive biomarker of the efficacy of nivolumab plus chemotherapy in patients with HER2-negative metastatic breast cancer (WJOG9917BTR)

Background: We have conducted a phase II trial (WJOG9917B) to evaluate efficacy of triple therapy with nivolumab, paclitaxel and bevacizumab in patients (pts) with HER2-negative metastatic breast cancer (MBC). Although soluble CD163 has been reported as a potential biomarker for predicting the efficacy of nivolumab in melanoma, however the data is limited in breast cancer. In an ancillary study (WJOG9917BTR), serum level of soluble CD163 were evaluated to elucidate this question. Methods: The main study enrolled 57 pts and showed that median Progression-free survival (PFS) and overall survival (OS) was 14.0 months and 32.5 months, respectively, with a median follow-up of 29.5 months. We have collected blood samples from consenting patients. Serum samples were collected at pretreatment, cycle 1 day 8 and other time points, which were used to measure the concentrations of cytokines, chemokines, and other surrogate proteins. PFS, OS, and response were analyzed in association with the biomarker data using the Kaplan–Meier method, log-rank tests as appropriate. Results: Biomarker study included 50 pts (36 with recurrent BC and 14 with de novo stage IV BC). The median amount of soluble CD163 before treatment was 562.3 (pg/ml) (range: 158.7-1518.0), and the baseline CD163 levels were higher in pts with recurrent than de novo stage IV (p = 0.0099). Other clinical factors including tumor subtypes, liver metastasis, response, PFS or OS were not significantly associated with the baseline CD163 levels. The kinetic changes in serum soluble CD163 after treatment were divided into two groups; one group (30 patients, CD163 increased group) had increased soluble CD163 immediately after administration (Cycle 1 Day 8), with a median PFS of 18.2; the other group (20 patients, CD163 decreased group) had decreased CD163 immediately after administration, with a median PFS of 13.6. There was a significantly difference in PFS between these two groups (hazard ratio 0.50 [0.26-0.93], log-rank test, p = 0.0263), but not in OS (p = 0.0548). These results suggested that the early change of serum soluble CD163 may be a predictive biomarker of efficacy of nivolumab plus chemotherapy in pts with HER2-negative MBC. Conclusions: Soluble CD163 may be a predictive biomarker for early detection of the efficacy of nivolumab plus chemotherapy in pts with HER2-negative MBC. (UMIN000029590)

Citation Format: Toru Mukohara, Yukinori Ozaki, Shigehisa Kitano, Makiko Yamashita, Daiki Ikarashi, Junji Tsurutani, Tsutomu Iwasa, Masato Takahashi, Norikazu Masuda, Manabu Futamura, Hironobu Minami, Koji Matsumoto, Yuko Tanabe, Hidetaka Kawabata, Kenichi Yoshimura, Toshimi Takano. Soluble CD163 may be a predictive biomarker of the efficacy of nivolumab plus chemotherapy in patients with HER2-negative metastatic breast cancer (WJOG9917BTR). [abstract]. In: Proceedings of the 2022 San Antonio Breast Cancer Symposium; 2022 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2023;83(5 Suppl):Abstract nr P5-02-42.

Abstract GS2-01: GS2-01 Trastuzumab deruxtecan vs physician’s choice in patients with HER2+ unresectable and/or metastatic breast cancer previously treated with trastuzumab emtansine: primary results of the randomized, phase 3 study DESTINY-Breast02

In DESTINY-Breast01 (NCT03248492) and DESTINY-Breast03 (NCT03529110), trastuzumab deruxtecan (T-DXd) demonstrated unprecedented activity in patients (pts) with HER2+ (immunohistochemistry 3+; immunohistochemistry 2+/in situ hybridization+) advanced metastatic breast cancer (mBC), leading to regulatory approvals in several countries for HER2+ unresectable/mBC after a prior anti–HER2-based regimen. DESTINY-Breast02 (NCT03523585) is a phase 3 trial of T-DXd vs treatment of physician’s choice (TPC) in patients with centrally confirmed HER2+ mBC previously treated with trastuzumab emtansine (T-DM1). It acts as a confirmatory study for the pivotal phase 2 DESTINY-Breast01 trial. Here we report the primary results of DESTINY-Breast02.

Methods: Pts with HER2+ mBC were randomized 2:1 to receive T-DXd or TPC (trastuzumab + capecitabine or lapatinib + capecitabine) and stratified by hormone receptor (HR) status (HR+/HR-), prior pertuzumab treatment, and history of visceral disease. The primary endpoint of this time-driven primary analysis was progression-free survival (PFS) as determined by blinded independent central review (BICR). The powered secondary endpoint was overall survival (OS). Other secondary endpoints included confirmed objective response rate (ORR) by BICR, duration of response (DoR) by BICR, PFS by investigator assessment, safety, and others.

Results: 608 pts were randomized to receive T-DXd (n = 406) or TPC (n = 202). Pts receiving T-DXd and TPC had a median age of 54.2 years (range, 22.4-88.5 years) and 54.7 years (range, 24.7-86.5 years), respectively, with a median of 2 (range, 0-10 and range,1-8) prior lines of systemic therapy (excluding hormone therapy) in the metastatic setting. Median treatment duration was 11.3 mo in the T-DXd arm and ~4.5 mo in the TPC arm. Efficacy and safety results are shown in the table below. T-DXd significantly improved PFS (HR, 0.36; 95% CI, 0.28-0.45; P &lt;0.000001) and OS (HR, 0.66; 95% CI, 0.50-0.86; P = 0.0021) compared with TPC. Confirmed ORR was 69.7% (14% complete response) with T-DXd and 29.2% (5.0% complete response) with TPC. Grade ≥3 treatment-emergent adverse events (TEAEs) occurred in 52.7% and 44.1% of pts receiving T-DXd and TPC, respectively. Adjudicated drug-related interstitial lung disease (ILD) occurred in 10.4% of pts with T-DXd vs 0.5% of pts with TPC. In pts receiving T-DXd, most ILD cases (88.1%) were grade 1/2 and grade 5 ILD was reported in 2 (0.5%) pts.

Conclusions: Results from DESTINY-Breast02 confirmed the clinical benefit and superiority of T-DXd over conventional chemotherapy-based regimens in pts with HER2+ mBC previously treated with T-DM1, as evidenced by significant and clinically meaningful improvements in PFS and OS. These data, together with earlier reported results from the DESTINY-Breast03 study of T-DXd vs T-DM1 solidify T-DXd as an optimal treatment option in pts with progressive HER2+ mBC across broad settings.

Editorial Acknowledgment

Under guidance of the authors, assistance in medical writing and editorial support was provided by Caylin Bosch, PhD, of ApotheCom, and was funded by Daiichi Sankyo.

Funding

This study was funded by Daiichi Sankyo and AstraZeneca.

Table. Summary of Efficacy and Safety Results for T-DXd and TPC in Patients With HER2+ mBC Previously Treated With T-DM1

Citation Format: Ian Krop, Yeon H. Park, Sung-Bae Kim, Giuliano Borges, Sercan Aksoy, Joaquin Gavila Gregori, Rebecca Roylance, Elgene Lim, Rinat Yerushalmi, Flora Zagouri, Francois P. Duhoux, Tanja Fehm, Toshimi Takano, Anton Egorov, Iris Wu, Jillian Cathcart, Changan Chu, Fabrice Andre. GS2-01 Trastuzumab deruxtecan vs physician’s choice in patients with HER2+ unresectable and/or metastatic breast cancer previously treated with trastuzumab emtansine: primary results of the randomized, phase 3 study DESTINY-Breast02 [abstract]. In: Proceedings of the 2022 San Antonio Breast Cancer Symposium; 2022 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2023;83(5 Suppl):Abstract nr GS2-01.

The impact of obesity and endocrine therapy on the prognosis of premenopausal women with hormone receptor-positive breast cancer: A single-institute retrospective study

BACKGROUND

Higher body mass index (BMI) is associated with worse prognosis in pre- and postmenopausal patients with breast cancer (BC). However, there is insufficient evidence regarding the optimal adjuvant endocrine therapy for obese premenopausal women with hormone receptor (HR)-positive BC.

AIM

To evaluate the impact of obesity and adjuvant endocrine therapy on prognosis in premenopausal patients with BC.

METHODS AND RESULTS

We retrospectively reviewed the medical record of premenopausal women who received curative surgery for clinical stage I-III HR-positive BC from 2007 to 2017. Patients were classified into five groups according to BMI: underweight (UW), normal weight (NW), obese 1 degree (OB1), obese 2 degree (OB2), and obese 3 degree (OB3) categories. The primary analysis was a comparison of BC-specific survival (BCSS) according to BMI (UW/NW vs. OB1-3) and adjuvant endocrine therapy (with or without ovarian function suppression [OFS]). Of 13 021 patients, the data of 3380 patients were analyzed. BCSS in OB1-3 patients was significantly worse than that in patients with UW/NW (hazard ratio [HR] 2.37; 95% confidence interval [CI], 1.40-4.02: p = .0009). In OB1-3 patients who received tamoxifen (TAM), BCSS was significantly worse than that in UW/NW patients (p = .0086); however, a significant difference was not shown in patients who received TAM and OFS (p = .0921).

CONCLUSION

High BMI was associated with worse prognosis in premenopausal patients with HR-positive BC who received adjuvant TAM. The role of OFS as adjuvant endocrine therapy remains unclear, and further studies are required to explore the adequate management of obese premenopausal patients.

[Challenges to International Collaborative Clinical Research and Approval Disparities]

The standard treatment and prognosis of breast cancer are improving as because of international collaborative clinical research. Generally, the standard treatment for breast cancer in Japan is not different from that in the US, Europe or other Asian countries, however, some novel agents have not been developed or have been delayed. For example, no institution in Japan has participated in the clinical trials of sacituzumab-govitecan. Institutions in Japan participated in the clinical trial of alpelisib and neratinib, however, the development of these drugs was delayed due to the racial difference and lack of a company in charge. On the other hand, there are international collaborative trials that Japan has participated in or has taken the lead, such as POSITIVE trial, CREATE-X trial, and PATHWAY trial. There are many challenges for Japan to participate in or lead international collaborative trials with Europe, US, or Asia. It is necessary to build a network and infrastructure for international collaborative trials based on the cooperation between the institutions and clinical trial groups in the world.

Transcriptomic intratumor heterogeneity of breast cancer patient-derived organoids may reflect the unique biological features of the tumor of origin

BACKGROUND

The intratumor heterogeneity (ITH) of cancer cells plays an important role in breast cancer resistance and recurrence. To develop better therapeutic strategies, it is necessary to understand the molecular mechanisms underlying ITH and their functional significance. Patient-derived organoids (PDOs) have recently been utilized in cancer research. They can also be used to study ITH as cancer cell diversity is thought to be maintained within the organoid line. However, no reports investigated intratumor transcriptomic heterogeneity in organoids derived from patients with breast cancer. This study aimed to investigate transcriptomic ITH in breast cancer PDOs.

METHODS

We established PDO lines from ten patients with breast cancer and performed single-cell transcriptomic analysis. First, we clustered cancer cells for each PDO using the Seurat package. Then, we defined and compared the cluster-specific gene signature (ClustGS) corresponding to each cell cluster in each PDO.

RESULTS

Cancer cells were clustered into 3-6 cell populations with distinct cellular states in each PDO line. We identified 38 clusters with ClustGS in 10 PDO lines and used Jaccard similarity index to compare the similarity of these signatures. We found that 29 signatures could be categorized into 7 shared meta-ClustGSs, such as those related to the cell cycle or epithelial-mesenchymal transition, and 9 signatures were unique to single PDO lines. These unique cell populations appeared to represent the characteristics of the original tumors derived from patients.

CONCLUSIONS

We confirmed the existence of transcriptomic ITH in breast cancer PDOs. Some cellular states were commonly observed in multiple PDOs, whereas others were specific to single PDO lines. The combination of these shared and unique cellular states formed the ITH of each PDO.

Effect of Trastuzumab Deruxtecan on QT/QTc Interval and Pharmacokinetics in HER2-Positive or HER2-Low Metastatic/Unresectable Breast Cancer

HER2-targeted anticancer therapies may be associated with cardiovascular adverse events. This study evaluated effects of the HER2-targeted antibody-drug conjugate trastuzumab deruxtecan (T-DXd, DS-8201a) on QT/QTc interval and its pharmacokinetics. Patients with heavily pretreated, metastatic HER2-expressing breast cancer were enrolled at seven study sites in Japan. T-DXd was administered intravenously at 6.4 mg/kg on day 1 of each 21-day cycle. Primary end points were baseline-adjusted QTcF interval and pharmacokinetics parameters. Key secondary end points included safety events, serum concentration of T-DXd and DXd at the time of electrocardiographic measurements, and antitumor activity parameters. Among 51 total patients, 47 (92.2%) had HER2-low breast cancer (immunohistochemistry 1+ or 2+ and in situ hybridization-negative/equivocal/missing). Pharmacokinetic parameters after a single dose of T-DXd were consistent with previous studies. After multiple doses, T-DXd showed moderate accumulation (accumulation ratio (cycle 3/cycle 1), 1.35), but DXd showed minimal accumulation (1.09). The upper bound of the 90% confidence interval for mean ΔQTcF interval was < 10 ms at all timepoints, and at mean maximum serum concentration was also < 10 ms. Based on concentration-QT analysis, ΔQTcF increased with increasing concentrations of T-DXd and DXd. No clinically meaningful QTcF prolongation was observed. T-DXd had a manageable safety profile and showed antitumor activity in HER2-low breast cancer. In this study, a T-DXd dose of 6.4 mg/kg, higher than the 5.4-mg/kg dose currently approved for breast cancer, was not associated with clinically relevant QTcF prolongation in heavily pretreated patients with HER2-expressing metastatic breast cancer. This study adds to our understanding of T-DXd for treatment of HER2-low breast cancer.

Trastuzumab Deruxtecan in HER2-Positive Metastatic Breast Cancer Patients with Brain Metastases: A DESTINY-Breast01 Subgroup Analysis

DESTINY-Breast01 (NCT03248492) evaluated trastuzumab deruxtecan (T-DXd; DS-8201) in patients with heavily pretreated HER2-positive metastatic breast cancer (mBC). We present a subgroup of 24 patients with a history of treated brain metastases (BM), a population with limited treatment options. In patients with BMs, the confirmed objective response rate (cORR) was 58.3% [95% confidence interval (CI), 36.6%-77.9%], and the median progression-free survival (mPFS) was 18.1 months (95% CI, 6.7-18.1 months). In patients without BMs (n = 160), cORR was 61.3% and mPFS was 16.4 months. Eight patients (47.1%) experienced a best overall intracranial response of partial response or complete response. Seven patients (41.2%) had a best percentage change in brain lesion diameter from baseline consistent with stable disease. Two patients (8.3%) with BMs and two (1.3%) without BMs experienced progression in the brain. The safety profile of T-DXd was consistent with previous studies. The durable clinical activity of T-DXd in this population warrants further investigation.

SIGNIFICANCE

Advances in treating HER2-positive metastatic breast cancer have greatly improved patient outcomes, but intracranial progression remains an important risk for which few therapeutic options are currently available. T-DXd demonstrated durable efficacy in patients with stable, treated BMs. This article is highlighted in the In This Issue feature, p. 2711.

Data of programmed death-ligand 1 expression and VEGF: Nivolumab, bevacizumab and paclitaxel For HER2-negative metastatic breast cancer

The purpose was to explore potential biomarkers of the efficacy and toxicity of triple therapy of nivolumab, bevacizumab and paclitaxel in patients with HER2-negative metastatic breast cancer (MBC). Tumor tissues before treatment and blood samples at pretreatment, during and after treatment were collected. The serum samples were used to measure the concentrations of cytokines. Progression-free survival (PFS), overall survival (OS), and response were analyzed in association with the biomarker data using the Kaplan–Meier method and log-rank tests. Fifty patients were included in the biomarker analysis. Programmed death-ligand 1 (PD-L1) expression on tumor cells and immune cells were evaluated in tumor tissue samples using a Dako 28-8 immunohistochemistry assay and using a VENTANA SP142 immunohistochemistry assay. PD-L1 positive rates using anti-PD-L1 antibodies 28-8 (Combined positive score [CPS] ≥1) and SP142 (Immune cells [IC] ≥1) were 15% and 17%, respectively. The PFS and OS were not significantly different in the subgroups by PD-L1 expression. The median pretreatment vascular endothelial growth factor (VEGF)-A concentration was 116.1 pg/ml (range 0–740.23 pg/ml) on day 1 and decreased to <37 pg/ml on day 8 of cycle 1 in all patients. Subtypes (hormone receptor-positive HER2-negative or triple negative breast cancer), stage (recurrent or de novo stage IV) and liver metastasis (yes or no) were not significantly different between patients in VEGF-A high and VEGF-A low groups. PFS in the VEGF-A high group was similar to that in the VEGF-A low group.

Pertuzumab retreatment for HER2-positive advanced breast cancer: a randomized, open-label phase III study (PRECIOUS)

No standard options existed for human epidermal growth factor receptor 2 (HER2)‐positive advanced breast cancer that progresses after second‐line trastuzumab emtansine therapy before 2020. The purpose of this study was to examine the efficacy of pertuzumab retreatment after disease progression following pertuzumab‐containing therapy for HER2‐positive locally advanced or metastatic breast cancer for the first time. This randomized, open‐label, multicenter phase III trial was undertaken in 93 sites in Japan. Eligible patients with HER2‐positive breast cancer who had received pertuzumab, trastuzumab, and chemotherapy as first‐ and/or second‐line therapy were randomly assigned (1:1) to: (i) pertuzumab, trastuzumab, and physician's choice chemotherapy (PTC), or (ii) trastuzumab and physician's choice chemotherapy (TC). The primary end‐point was investigator‐assessed progression‐free survival (PFS). Between August 1, 2015 and December 31, 2018, 219 patients were randomized to PTC (n = 110) or TC (n = 109). Median follow‐up was 14.2 months (interquartile range, 9.0–22.2), and median PFS was 5.3 months (95% confidence interval [CI], 4.0–6.6) with PTC and 4.2 months (95% CI, 3.2–4.8) with TC (stratified hazard ratio 0.76 [95% CI upper limit 0.967]; p = 0.022). Progression‐free survival was improved by adding pertuzumab in all prespecified subgroups. The PTC arm showed a trend towards better overall survival and duration of response, but similar objective response and health‐related quality of life. The incidence of treatment‐related adverse events was similar between groups except for diarrhea. Pertuzumab retreatment contributes to disease control for HER2‐positive locally advanced or metastatic breast cancer previously treated with pertuzumab‐containing regimens.

Safety and efficacy of nivolumab plus bevacizumab, paclitaxel for HER2-negative metastatic breast cancer: Primary results and biomarker data from a phase 2 trial (WJOG9917B)

BACKGROUND

Preclinical models revealed potential synergistic effects of programmed cell death-1 inhibitors and anti-vascular endothelial growth factor (VEGF) antibodies. Therefore, we investigated the use of nivolumab, bevacizumab, and paclitaxel triple therapy for metastatic breast cancer.

METHODS

This phase 2, multicentre, single-arm study (NEWBEAT) investigated the safety and efficacy of first-line nivolumab, paclitaxel, and bevacizumab in patients with human epidermal growth factor receptor 2-negative metastatic breast cancer, regardless of programmed cell death-ligand 1 expression. The primary end-point was objective response rate. Key secondary end-points included progression-free survival, overall survival, and toxicities. A biomarker study evaluated tumour programmed cell death-ligand 1 expression and serum VEGF-A levels.

RESULTS

Between February 2018 and October 2018, 57 patients were enrolled. An objective response rate was seen in 39/56 patients (70%, 95% confidence interval [CI]: 55.9-81.2%), meeting the primary end-point. The objective response rate was 74% in patients with hormone receptor-positive breast cancer versus 59% in patients with triple-negative breast cancer. The median progression-free survival and overall survival were 14.0 (95% CI 11.0-16.3) and 32.5 (95% CI 26.0-not evaluable) months, respectively (median follow-up: 29.5 months). Grade 3/4 adverse drug reactions occurred in 33 of 57 patients (58%). There were no grade 5 adverse events. Immune-related adverse events occurred in 43 of 57 patients (75%), with grade 3/4 events in eight patients (14%). Biomarker analysis showed that tumour programmed cell death-ligand 1 expression was not correlated with the efficacy of triple therapy. Efficacy outcomes were similar between the serum VEGF-high and VEGF-low groups.

CONCLUSIONS

First-line nivolumab, bevacizumab, and paclitaxel therapy showed promising efficacy and manageable toxicity in patients with human epidermal growth factor receptor 2-negative metastatic breast cancer.

Factors associated with overall survival after recurrence in patients with ER-positive/HER2-negative postmenopausal breast cancer: an ad hoc analysis of the JBCRG-C06 Safari study

BACKGROUND

The Safari study (UMIN000015168) was a retrospective, multicenter study in which 1072 consecutive cases of estrogen receptor-positive advanced breast cancer treated using 500 mg fulvestrant were registered. We previously reported the relationship between the patient factors and overall survival after the diagnosis using the same cases and the same factors for the analysis of time to treatment failure in patients with estrogen receptor-positive advanced breast cancer. The current study is an ad hoc analysis that focused on the relationship between the patient factors and overall survival after recurrence by adding factors generally associated with overall survival after recurrence.

METHODS

The overall survival after recurrence in patients with estrogen receptor-positive human epidermal growth factor receptor 2 negative recurrent breast cancer was analyzed via univariate and multivariate analyses with a Cox proportional hazards model.

RESULTS

A total of 598 cases were used for the analysis of overall survival after recurrence. Multivariate analysis revealed that favorable overall survival (median, 6.4 years) was significantly correlated with long time from recurrence to fulvestrant use (≥3 years), low nuclear or histological grade (G3 vs. G1), long time to treatment failure of initial palliative endocrine therapy (≥12 months) and long time to initial palliative chemotherapy (≥2 years).

CONCLUSION

The results of this study indicate that sequential endocrine monotherapy may be a useful treatment option for patients with estrogen receptor-positive/human epidermal growth factor receptor 2 negative recurrent breast cancer who have been successfully treated with initial long-term palliative endocrine therapy.