Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
Clinical Trial
. 2021 Aug;32(8):994-1004.
doi: 10.1016/j.annonc.2021.05.801. Epub 2021 Jul 1.

Primary results from IMpassion131, a double-blind, placebo-controlled, randomised phase III trial of first-line paclitaxel with or without atezolizumab for unresectable locally advanced/metastatic triple-negative breast cancer

D Miles  1 , J Gligorov  2 , F André  3 , D Cameron  4 , A Schneeweiss  5 , C Barrios  6 , B Xu  7 , A Wardley  8 , D Kaen  9 , L Andrade  10 , V Semiglazov  11 , M Reinisch  12 , S Patel  13 , M Patre  14 , L Morales  14 , S L Patel  15 , M Kaul  13 , T Barata  16 , J O'Shaughnessy  17 ; IMpassion131 investigators
Collaborators, Affiliations
Free article
Clinical Trial

Primary results from IMpassion131, a double-blind, placebo-controlled, randomised phase III trial of first-line paclitaxel with or without atezolizumab for unresectable locally advanced/metastatic triple-negative breast cancer

D Miles et al. Ann Oncol. 2021 Aug.
Free article

Abstract

Background: In the phase III IMpassion130 trial, combining atezolizumab with first-line nanoparticle albumin-bound-paclitaxel for advanced triple-negative breast cancer (aTNBC) showed a statistically significant progression-free survival (PFS) benefit in the intention-to-treat (ITT) and programmed death-ligand 1 (PD-L1)-positive populations, and a clinically meaningful overall survival (OS) effect in PD-L1-positive aTNBC. The phase III KEYNOTE-355 trial adding pembrolizumab to chemotherapy for aTNBC showed similar PFS effects. IMpassion131 evaluated first-line atezolizumab-paclitaxel in aTNBC.

Patients and methods: Eligible patients [no prior systemic therapy or ≥12 months since (neo)adjuvant chemotherapy] were randomised 2:1 to atezolizumab 840 mg or placebo (days 1, 15), both with paclitaxel 90 mg/m2 (days 1, 8, 15), every 28 days until disease progression or unacceptable toxicity. Stratification factors were tumour PD-L1 status, prior taxane, liver metastases and geographical region. The primary endpoint was investigator-assessed PFS, tested hierarchically first in the PD-L1-positive [immune cell expression ≥1%, VENTANA PD-L1 (SP142) assay] population, and then in the ITT population. OS was a secondary endpoint.

Results: Of 651 randomised patients, 45% had PD-L1-positive aTNBC. At the primary PFS analysis, adding atezolizumab to paclitaxel did not improve investigator-assessed PFS in the PD-L1-positive population [hazard ratio (HR) 0.82, 95% confidence interval (CI) 0.60-1.12; P = 0.20; median PFS 6.0 months with atezolizumab-paclitaxel versus 5.7 months with placebo-paclitaxel]. In the PD-L1-positive population, atezolizumab-paclitaxel was associated with more favourable unconfirmed best overall response rate (63% versus 55% with placebo-paclitaxel) and median duration of response (7.2 versus 5.5 months, respectively). Final OS results showed no difference between arms (HR 1.11, 95% CI 0.76-1.64; median 22.1 months with atezolizumab-paclitaxel versus 28.3 months with placebo-paclitaxel in the PD-L1-positive population). Results in the ITT population were consistent with the PD-L1-positive population. The safety profile was consistent with known effects of each study drug.

Conclusion: Combining atezolizumab with paclitaxel did not improve PFS or OS versus paclitaxel alone. CLINICALTRIALS.GOV: NCT03125902.

Keywords: PD-L1; advanced breast cancer; atezolizumab; immune checkpoint inhibitor; paclitaxel; triple-negative breast cancer.

PubMed Disclaimer

Conflict of interest statement

Disclosure DM has received honoraria for advisory boards from Roche/Genentech, Genomic Health and Eisai and has been an invited speaker for Roche/Genentech and Genomic Health. JG has received consulting fees from Daichi, Eisai, Genomic Health, Ipsen, Macrogenics, MSD, Mylan, Novartis, Onxeo, Pfizer and Roche/Genentech; research grants (to institution) from Daichi, Eisai, Genomic Health, Novartis, Pfizer, Roche/Genentech and Immunomedics; and travel/accommodation/expenses from Eisai, Genomic Health, Novartis, Pfizer and Roche/Genentech. FA has received research grants (to institution) from AstraZeneca, Lilly, Novartis, Pfizer and Roche and travel/accommodation/expenses from AstraZeneca, GlaxoSmithKline, Novartis and Roche. DC’s institution has received honoraria for his advisory/consultancy roles with Roche and AstraZeneca. AS has received honoraria for scientific talks from Roche, Celgene, AstraZeneca, Pfizer, MSD, Tesaro, Lilly and Novartis, and for advisory/consultancy roles from Roche and AstraZeneca; research funding (to institution) from Roche, Celgene, AbbVie and Molecular Partner; and travel support from Roche, Pfizer and Celgene. CB has received honoraria for advisory/consultancy roles from Boehringer Ingelheim, GSK, Novartis, Pfizer, Lilly, Roche/Genentech, Eisai, MSD, AstraZeneca and Bayer; research grants/funding (to institution) from AbbVie, Amgen, Astellas Pharma, AstraZeneca, Bristol-Myers Squibb, Celgene, Covance, Lilly, Medivation, Merck Serono, MSD, Novartis, Pfizer, PharmaMar and Roche/Genentech; and travel/accommodation/expenses from Boehringer Ingelheim, GSK, Novartis, Pfizer, Lilly, Roche/Genentech, Eisai, MSD, AstraZeneca and Bayer. BX has received honoraria for consulting/advisory roles from Novartis, Roche and AstraZeneca and research funding (to institution) from Pfizer, Roche, AstraZeneca, Novartis and Daiichi-Sankyo. AW reports personal fees from Roche, NAPP, Amgen, MSD, Novartis, Pfizer, AstraZeneca, Pierre Fabre, ACCORD, Athenex, Gerson Lehmann Group, Coleman Expert Network Group and Guidepoint Global, and also reports personal fees and other from Lilly and Daiichi-Sankyo (all outside the submitted work) and employment with AstraZeneca after completion of this work. DK reports consulting fees from Roche, Boehringer Ingelheim, Pfizer, MSD, BMS, Novartis, AstraZeneca, Raffo-Tecnofarma, Varifarma and Takeda and research funding (to institution) from Roche, Lilly Oncology, Clovis, MSD, AbbVie, Takeda, Novartis, Pfizer and Array BioPharma Inc. LA reports consulting/advisory roles for Zodiac Pharma, Janssen-Cilag and Roche/Genentech; speakers’ bureau for Janssen-Cilag, Zodiac Pharma, Merck Sharp & Dohme, Roche/Genentech and Novartis; research funding (to institution) from Bayer, Roche/Genentech, Janssen-Cilag and Regeneron; and travel/accommodation/expenses from Zodiac Pharma. MR reports consulting fees/advisory roles for Roche Pharma AG, Novartis, MSD, AstraZeneca, Hexal, Lilly, Somatex and Pfizer and travel/accommodation/expenses from Pfizer, Celgene and Novartis. MP, LM and TB are employees of and hold shares in F. Hoffmann-La Roche Ltd. SP, SLP and MK are employees of Genentech, Inc., and hold shares in F. Hoffmann-La Roche Ltd. JO’S has received honoraria for advisory/consultancy from AbbVie Inc., Agendia, Amgen Biotechnology, AstraZeneca, Bristol-Myers Squibb, Celgene Corporation, Eisai, Genentech, Genomic Health, GRAIL, Immunomedics, Heron Therapeutics, Ipsen Biopharmaceuticals, Jounce Therapeutics, Lilly, Merck, Myriad, Novartis, Odonate Therapeutics, Pfizer, Puma Biotechnology, Prime Oncology, Roche, Seattle Genetics, Syndax Pharmaceuticals and Takeda. VS has declared no conflicts of interest.

Publication types

MeSH terms

Associated data