Combination of Talimogene Laherparepvec With Atezolizumab in Early Breast Cancer

Summary

PROMETEO is a window opportunity, single arm, exploratory study to evaluate the effect of T- VEC combined with Atezolizumab in women with operable early breast cancer who present residual disease after Neoadjuvant Chemotherapy (NAC). Other eligibility criteria include TNBC or LumB like primary tumor sized at least 1.5 cm, ECOG PS 0-1 and evaluable diagnostic tumor sample.

Timeline

Start

2018-12-10

Primary completion

2022-04-27

Completion

2025-03-18

Outcome

Met primary endpoint

paper At surgery, 7 patients (26.9%) achieved Residual Cancer Burden (RCB)-0/I (primary endpoint) PMID 41698899 ↗

paper The trial met its pre-specified efficacy and safety endpoints. PMID 41698899 ↗

Publications

• Pascual T, Vidal M, Cejalvo JM, Vega E, Sanfeliu E, Villacampa G, Ganau S, Parreno AMJ, Zamora E, Miranda I, Delgado A, Bermejo B, Segui E, Braso-Maristanty F, de la Cruz-Merino L, Juan M, Galvan P, Gonzalez-Farre X, Chillara S, Villagrasa P, Pfefferle AD, O'Connell CE, Ferrero-Cafiero JM, Oliveira M, Perou CM, Prat A. Talimogene laherparepvec and atezolizumab in HER2-negative breast cancer following neoadjuvant chemotherapy: a window-of-opportunity phase II trial (SOLTI-1503 PROMETEO). Nat Commun. 2026 Feb 16;17(1):2817. doi: 10.1038/s41467-026-69222-5.
• Pascual T, Cejalvo JM, Oliveira M, Vidal M, Vega E, Ganau S, Julve A, Zamora E, Miranda I, Delgado A, Bermejo B, la Cruz-Merino L, Juan M, Ferrero-Cafiero JM, Canes J, Gonzalez X, Villagrasa P, Prat A. SOLTI-1503 PROMETEO TRIAL: combination of talimogene laherparepvec with atezolizumab in early breast cancer. Future Oncol. 2020 Aug;16(24):1801-1813. doi: 10.2217/fon-2020-0246. Epub 2020 Jul 7.

Drugs

Evaluation	Drug	Modality	Dose	Route
Subject	Atezolizumab	Monoclonal antibody	840 mg	Intravenous
Subject	Talimogene Laherparepvec	Other / unclassified	1e+08 unknown	Other

Indications