Mayo's randomized Phase 2 trial across 11 sites tested low-dose (825 μg) against high-dose (2.5 mg) TPIV200, a multi-epitope folate-receptor-alpha peptide vaccine adjuvanted with GM-CSF, with or without cyclophosphamide pretreatment in early-stage triple-negative breast cancer. The low dose matched the full dose on immunogenicity, cyclophosphamide pretreatment had no impact, and vaccination induced persistent polyepitope immunity. Kathryn Ruddy, Keith Knutson, and Saranya Chumsri presented the data June 1.
ASCO's Sunday education and poster sessions in Chicago set up the meeting's densest peptide-oncology day on Monday, June 1, when Bicycle Therapeutics presents Duravelo-2 (zelenectide pevedotin in first-line urothelial cancer, Abstract 4516), Mayo Clinic presents the TPIV200 folate-receptor-alpha vaccine in triple-negative breast cancer (Abstract 536), and Telix presents ProstACT Global PSMA radioligand data. Corbus CRB-701 and BioVaxys MVP-S round out the targeted-conjugate and vaccine slate.
ASCO 2026 Day 2 in Chicago continued the meeting's peptide-and-targeted-conjugate oncology programming. Saturday May 30 brought the Immutep eftilagimod alfa survival pooled analysis and the ImPact Biotech padeliporfin VTP pancreatic data, alongside the Bicycle Therapeutics zelenectide pevedotin dose-optimization poster (Abstract 4567, May 31) approaching. The meeting's heaviest peptide-mechanism day is Monday June 1: Bicycle Duravelo-2 zelenectide pevedotin + pembrolizumab oral presentation in 1L urothelial (Abstract 4516, 8:30 AM CT); Mayo Clinic TPIV200 folate-receptor peptide vaccine in triple-negative breast cancer (Abstract 536, 1:30 PM CT); Telix ProstACT PSMA radioligand Phase 3 Part 1; Sapience lucicebtide GBM poster. The Corbus CRB-701 Nectin-4 ADC data (42.9% OPSCC / 34.4% cervical) landed Friday May 29. The targeted-conjugate categories — Nectin-4, PSMA, B7-H3, FAP, SSTR2 — remain the densest peptide-adjacent oncology competition, with the bulk of definitive readouts concentrated in the meeting's back half through June 2.
Mayo Clinic researchers led by Dr. Kathryn Ruddy will present a randomized Phase 2 trial of the folate receptor alpha (FRα) peptide vaccine TPIV200 in early-stage triple-negative breast cancer at ASCO 2026 (Abstract 536, June 1, 1:30-4:30 PM CDT). The trial dosed 80 patients with vaccine; 58 were evaluable for immunogenicity. The TPIV200 multi-epitope FRα peptide vaccine was found safe and immunogenic using a single low-dose injection without cyclophosphamide priming. FRα is overexpressed on the cell surface in breast, ovarian, and lung cancers, making it a shared-antigen vaccine target distinct from personalized neoantigen approaches. The data supports combining TPIV200 with an immune checkpoint inhibitor to extend recurrence-free or progression-free survival in TNBC — the breast cancer subtype with the highest mortality risk and fewest targeted-therapy options. The vaccine adds to the peptide cancer vaccine cohort (BioVaxys MVP-S, Dana-Farber NeoVax, Greenwich GP2) at ASCO 2026.