A note on versions:The version presented here may differ from the published version or from the version of record. If you wish to cite this item you are advised to consult the publisher's version. Please see the repository url above for details on accessing the published version and note that access may require a subscription.For more information, please contact eprints@nottingham.ac.uk The objective of the current study was to confirm the superior PFS advantage for 103 fulvestrant versus anastrozole observed in the FIRST study, in a double-blind Phase 3 104 design. The population for FALCON were postmenopausal women with hormone 105 receptor-positive locally advanced or metastatic breast cancer who had not received 106 prior endocrine therapy, in order to avoid reducing efficacy of the control arm through 107 exposure to adjuvant endocrine therapy. 108 METHODS 109 Study design 110The Fulvestrant and AnastrozoLe COmpared in hormonal therapy Naïve advanced 111 breast cancer (FALCON) trial (Clinicaltrials.gov: NCT01602380) is a Phase 3 112 randomised, double-blind, double-dummy, international, multicentre study that 113 compared the efficacy and tolerability of fulvestrant with anastrozole in 114 postmenopausal women with histologically confirmed ER+ and/or PgR+ locally 115 advanced or metastatic breast cancer. 116 Ethical approval 117The study was conducted in accordance with the Declaration of Helsinki and 118International Conference on Harmonisation/Good Clinical Practice guidelines. An 119 Randomisation and masking 133Patients were randomised sequentially (1:1) to fulvestrant 500 mg or anastrozole 1 mg 134 using a computer-generated randomisation scheme and an integrated voice/web 135 response system. Patients were stratified at randomisation according to locally 136 advanced or metastatic breast cancer; prior or no prior treatment with chemotherapy 137 for locally advanced or metastatic breast cancer; and measurable or non-measurable 138 disease. 139Study drugs were labelled using a unique identifier linked to the randomisation 140 scheme. The active study drug and placebo for fulvestrant (pre-filled syringes) and 141 anastrozole (tablets) were identically packaged to maintain blinding. 142 progression. Safety and tolerability were assessed at each study visit, and for up to 8 154 weeks after the last fulvestrant/placebo injection. HRQoL questionnaires were 155 administered at baseline and at 3-monthly intervals. Following disease progression or 156 treatment discontinuation, HRQoL questionnaires will be administered at 6-monthly 157 until a final OS analysis. 158 Outcomes 159The primary endpoint of the study was to demonstrate the superior PFS of patients 160 treated with fulvestrant vs anastrozole. A progression event was determined based on 161 tumour assessments performed locally by each investigator, and was defined by 162Response Evaluation Criteria in Solid Tumours (RECIST) 1·1, or 163 surgery/radiotherapy for worsening of disease, or death from any cause. 164 OS and ORR were tested using a multiple ...

Purpose This phase III study compared SB3, a trastuzumab (TRZ) biosimilar, with reference TRZ in patients with human epidermal growth factor receptor 2-positive early breast cancer in the neoadjuvant setting ( ClinicalTrials.gov identifier: NCT02149524). Patients and Methods Patients were randomly assigned to receive neoadjuvant SB3 or TRZ for eight cycles concurrently with chemotherapy (four cycles of docetaxel followed by four cycles of fluorouracil, epirubicin, and cyclophosphamide) followed by surgery, and then 10 cycles of adjuvant SB3 or TRZ. The primary objective was comparison of breast pathologic complete response (bpCR) rate in the per-protocol set; equivalence was declared if the 95% CI of the ratio was within 0.785 to 1.546 or the 95% CI of the difference was within ± 13%. Secondary end points included comparisons of total pathologic complete response rate, overall response rate, event-free survival, overall survival, safety, pharmacokinetics, and immunogenicity. Results Eight hundred patients were included in the per-protocol set (SB3, n = 402; TRZ, n = 398). The bpCR rates were 51.7% and 42.0% with SB3 and TRZ, respectively. The adjusted ratio of bpCR was 1.259 (95% CI, 1.085 to 1.460), which was within the predefined equivalence margins. The adjusted difference was 10.70% (95% CI, 4.13% to 17.26%), with the lower limit contained within and the upper limit outside the equivalence margin. The total pathologic complete response rates were 45.8% and 35.8% and the overall response rates were 96.3% and 91.2% with SB3 and TRZ, respectively. Overall, 96.6% and 95.2% of patients experienced one or more adverse event, 10.5% and 10.7% had a serious adverse event, and 0.7% and 0.0% had antidrug antibodies (up to cycle 9) with SB3 and TRZ, respectively. Conclusion Equivalence for efficacy was demonstrated between SB3 and TRZ on the basis of the ratio of bpCR rates. Safety and immunogenicity were comparable.

ClinicalTrials.gov (NCT02149524); EudraCT (2013-004172-35).

509 Background: SB3, a proposed biosimilar to the originator trastuzumab (TRZ), demonstrated similarity to its originator in terms of biological activities and pharmacokinetic (PK) equivalence. This study compared SB3 to TRZ in terms of efficacy, safety, PK, and immunogenicity in patients treated by neoadjuvant therapy for HER2 positive early breast cancer (NCT02149524). Methods: Phase III, randomized, double blind, multicenter study compared neoadjuvant SB3 or TRZ for 8 cycles concurrently given with chemotherapy (docetaxel followed by 5-fluorouracil/epirubicin/cyclophosphamide). Then patients underwent surgery followed by 10 cycles of SB3 or TRZ. The primary endpoint was breast pathologic complete response (bpCR) rate. Equivalence was declared if the 90% confidence interval (CI) of the ratio or the 95% CI of the difference of the bpCR rates in the per-protocol set (PPS) were contained within the pre-defined equivalence margins (0.785, 1.546) and (-13%, 13%), respectively. Secondary endpoints were total pathologic complete response (tpCR), overall response rate (ORR), event-free survival, PK, immunogenicity, and safety. Results: 800 patients were included in PPS. The bpCR rates were 51.7% for SB3 and 42.0% for TRZ. The ratio of bpCR rate was 1.259 and its 90% CI was 1.112-1.426, within the pre-defined equivalence margin. The difference of bpCR rate was 10.70% and its 95% CI was 4.13-17.26; the lower margin was contained within, the upper margin was outside the pre-defined equivalence margin. Secondary endpoints were comparable between SB3 vs TRZ: tpCR rate (45.8% vs 35.8%); ORR (96.3% vs 91.2%). Safety was comparable between SB3 vs TRZ during neoadjuvant period: incidence of treatment-emergent adverse events (96.6% vs 95.2%), most commonly neutropenia, alopecia, and nausea; incidence of serious adverse events (10.5% vs 10.7%). PK equivalence was demonstrated and immunogenicity between SB3 vs TRZ was comparable (0.7% vs 0.0%). Conclusions: Equivalence was demonstrated between SB3 and TRZ based on the ratio of bpCR rates. Safety, PK, and immunogenicity were similar. Complete safety and survival data will follow. Clinical trial information: NCT02149524.