Efficacy and safety of the therapeutic cancer vaccine tecemotide (L-BLP25) in early breast cancer: Results from a prospective, randomised, neoadjuvant phase II study (ABCSG 34)

Eur J Cancer. 2020 Jun;132:43-52. doi: 10.1016/j.ejca.2020.03.018. Epub 2020 Apr 20.

Abstract

Background: Immune-based strategies represent a promising approach in breast cancer (BC) treatment. The glycoprotein mucin-1 (MUC-1) is overexpressed in more than 90% of BC patients, and is targeted by the cancer vaccine tecemotide. We have investigated the efficacy and safety of tecemotide when added to neoadjuvant standard-of-care (SoC) treatment in early BC patients.

Patients and methods: A total of 400 patients with HER2-early BC were recruited into this prospective, multicentre, randomised 2-arm academic phase II trial. Patients received preoperative SoC treatment (chemotherapy or endocrine therapy) with or without tecemotide. Postmenopausal women with oestrogen receptor (ER)+++, or ER++ and Ki67 < 14%, and G1,2 tumours ('luminal A' tumours) received 6 months of letrozole. Postmenopausal patients with triple-negative, ER-/+/++ and Ki67 ≥ 14%, and with G3 tumours, as well as premenopausal patients, received four cycles of epirubicin/cyclophosphamide plus four cycles of docetaxel. Primary end-point was residual cancer burden (RCB; 0/I versus II/III) at surgery. Secondary end-points included pathological complete response (pCR), safety, and quality of life.

Findings: We observed no significant difference in RCB 0/I rates between patients with (36.4%) and without (31.9%) tecemotide in the overall study population (p = 0.40) nor in endocrine and chemotherapy-treated subgroups (25.0% versus 13.3%, p = 0.17; 39.6% versus 37.8%, p = 0.75, respectively). The addition of tecemotide did not affect overall pCR rates (22.5% versus 17.4%, p = 0.23), MUC-1 expression, or tumour-infiltrating lymphocytes content. Tecemotide did not increase toxicity when compared to SoC therapy alone.

Interpretation: Neoadjuvant tecemotide is safe, but does not improve RCB or pCR rates in patients receiving standard neoadjuvant therapy.

Keywords: Breast cancer; Cancer vaccine; MUC-1; Neoadjuvant treatment; Tecemotide.

Publication types

  • Clinical Trial, Phase II
  • Multicenter Study
  • Randomized Controlled Trial
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Aged
  • Aged, 80 and over
  • Biomarkers, Tumor / metabolism*
  • Breast Neoplasms / drug therapy*
  • Breast Neoplasms / metabolism
  • Breast Neoplasms / pathology
  • Cancer Vaccines / therapeutic use*
  • Female
  • Follow-Up Studies
  • Humans
  • Membrane Glycoproteins / therapeutic use*
  • Middle Aged
  • Patient Safety
  • Prognosis
  • Prospective Studies
  • Receptor, ErbB-2 / metabolism
  • Receptors, Estrogen / metabolism
  • Receptors, Progesterone / metabolism

Substances

  • Biomarkers, Tumor
  • Cancer Vaccines
  • L-BLP25
  • Membrane Glycoproteins
  • Receptors, Estrogen
  • Receptors, Progesterone
  • Receptor, ErbB-2