19-Peptide Cancer Vaccine Shows Promise in Refractory Triple-Negative Breast Cancer

A mixed 19-peptide cancer vaccine produced peptide-specific immune responses correlating with survival in refractory triple-negative breast cancer patients, with a median survival of 24.4 months in completers.

Toh, Uhi et al.·Cancer science·2020·Preliminary Evidenceclinical trial
RPEP-05167Clinical trialPreliminary Evidence2020RETHINKTHC RESEARCH DATABASErethinkthc.com/research

Quick Facts

Study Type
clinical trial
Evidence
Preliminary Evidence
Sample
N=small
Participants
14 patients with advanced metastatic TNBC refractory to chemotherapy

What This Study Found

Peptide-specific IgG responses correlated with overall survival (P < .01), and median OS was 24.4 months in the 10 patients who completed vaccination — notable for refractory mTNBC.

Key Numbers

n=14; 19 peptides; weekly x 6 weeks; mOS 11.5 mo (all) / 24.4 mo (10 completers); IgG-OS correlation p<0.01; no severe AEs

How They Did This

Phase II single-arm clinical trial, 14 patients, weekly vaccination for 6 weeks, immune response monitoring via peptide-specific IgG, survival analysis.

Why This Research Matters

Triple-negative breast cancer has the worst prognosis and fewest treatment options. A 24.4-month median survival in refractory patients is remarkable for this population.

The Bigger Picture

This trial provides early evidence that multi-peptide cancer vaccines can produce meaningful immune responses and survival benefits even in heavily pretreated TNBC patients.

What This Study Doesn't Tell Us

Very small single-arm trial (14 patients) without a control group. Selection bias in the completer analysis. Early phase data.

Questions This Raises

  • ?Would a randomized controlled trial confirm the survival benefit?
  • ?Can biomarkers like CRP identify patients most likely to benefit?
  • ?Could this vaccine be combined with checkpoint inhibitors for enhanced efficacy?

Trust & Context

Key Stat:
24.4 months Median overall survival in the 10 refractory mTNBC patients who completed the 19-peptide vaccination schedule
Evidence Grade:
Early phase II single-arm trial with very small sample (14 patients). Promising survival data but requires randomized confirmation.
Study Age:
Published in 2020. Peptide-based cancer vaccines for TNBC continue to be developed.
Original Title:
Early phase II study of mixed 19-peptide vaccine monotherapy for refractory triple-negative breast cancer.
Published In:
Cancer science, 111(8), 2760-2769 (2020)
Database ID:
RPEP-05167

Evidence Hierarchy

Meta-Analysis / Systematic Review
Randomized Controlled Trial
Cohort / Case-Control
Cross-Sectional / ObservationalSnapshot without intervening
This study
Case Report / Animal Study
What do these levels mean? →

Frequently Asked Questions

What is a peptide cancer vaccine?

A mixture of small protein fragments (peptides) from tumor-associated proteins is injected to train the immune system to recognize and attack cancer cells. This vaccine used 19 different peptides to broaden the immune response.

What is triple-negative breast cancer and why is it hard to treat?

TNBC lacks the three receptors (estrogen, progesterone, HER2) that most breast cancer drugs target. This makes it resistant to hormonal and HER2-targeted therapies, leaving chemotherapy as the main option. When chemo fails, treatment options are extremely limited.

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Cite This Study

RPEP-05167·https://rethinkpeptides.com/research/RPEP-05167

APA

Toh, Uhi; Sakurai, Sayaka; Saku, Shuko; Takao, Yuko; Okabe, Mina; Iwakuma, Nobutaka; Shichijo, Shigeki; Yamada, Akira; Itoh, Kyogo; Akagi, Yoshito. (2020). Early phase II study of mixed 19-peptide vaccine monotherapy for refractory triple-negative breast cancer.. Cancer science, 111(8), 2760-2769. https://doi.org/10.1111/cas.14510

MLA

Toh, Uhi, et al. "Early phase II study of mixed 19-peptide vaccine monotherapy for refractory triple-negative breast cancer.." Cancer science, 2020. https://doi.org/10.1111/cas.14510

RethinkPeptides

RethinkPeptides Research Database. "Early phase II study of mixed 19-peptide vaccine monotherapy..." RPEP-05167. Retrieved from https://rethinkpeptides.com/research/toh-2020-early-phase-ii-study

Access the Original Study

Study data sourced from PubMed, a service of the U.S. National Library of Medicine, National Institutes of Health.

This study breakdown was produced by the RethinkPeptides research team. We analyze and report published research findings without making health recommendations. All interpretations are based solely on the published abstract and study data.