Updated Efficacy Data of Ivonescimab Plus Chemotherapy as First-Line Treatment for TNBC at ESMO IO 2025

Akesco presented updated Phase II data of ivonescimab (PD‑1/VEGF bispecific antibody) plus chemotherapy as first-line treatment for locally advanced unresectable or metastatic triple-negative breast cancer (TNBC) at the ESMO Immuno-Oncology Congress 2025 in London.1 2

The analysis included 36 enrolled TNBC patients as of July 15, 2025, with 35 patients evaluable for efficacy; the median follow-up period was extended to 22.1 months, providing longer-term outcome data.1 2

In the overall efficacy set, ivonescimab plus chemotherapy achieved an objective response rate (ORR) of 80.0%, a disease control rate (DCR) of 100.0%, and a median duration of response (mDOR) of 12.2 months.1

The median progression-free survival (mPFS) for the overall population was 15.2 months, with a 12‑month PFS rate of 56.3%, indicating sustained disease control over time.1 5

Across *PD‑L1 CPS subgroups, efficacy remained high:*
in CPS ≥10, ORR 83.3%, DCR 100%, mDOR 12.2 months, mPFS 15.9 months, 12‑month PFS 66.7%.1 2

In the CPS <10 subgroup, ORR was 79.3%, DCR 100%, mDOR 9.9 months, and mPFS 13.04 months, with a 12‑month PFS rate of 54.3%, suggesting benefit even in lower PD‑L1–expressing tumors.1

In the CPS ≥1 subgroup, the regimen achieved an ORR of 72.2%, DCR 100%, mDOR 12.2 months, and mPFS 15.9 months, with a 12‑month PFS rate of 63.8%.1

Overall survival (OS) data are not yet mature, and follow-up is ongoing to better define long-term survival outcomes.1 2

The combination demonstrated a *favorable safety profile:*
no treatment-related adverse events (TRAEs) led to treatment discontinuation or death, and the most common TRAEs were predominantly grade 1–2 in severity.1 2

These longer-term Phase II data were described by the company as further validating the efficacy and safety of ivonescimab plus chemotherapy as a first-line option in TNBC compared with earlier interim readouts presented at ESMO 2024 and SABCS 2024.1 2

Based on the positive efficacy and safety profile from this Phase II study, ivonescimab plus chemotherapy for first-line TNBC has been included in the Breakthrough Therapy Designation (BTD) list by China’s Center for Drug Evaluation (CDE) under the National Medical Products Administration (NMPA).1 2

A multicenter, randomized, double-blind Phase III trial, HARMONi‑BC1 (AK112‑308), is ongoing to further evaluate ivonescimab plus chemotherapy in first-line TNBC, aiming to confirm these Phase II findings.1 2 3

Broader context reports note ivonescimab’s dual PD‑1 and VEGF-A targeting, with earlier Phase II data in TNBC showing high response rates and manageable toxicity, and the Phase III HARMONi‑BC1 trial expected to complete around late 2026.3

Independent previews of ESMO IO 2025 highlighted ivonescimab plus chemotherapy in TNBC, summarizing key updated metrics as ORR 80% and mPFS 15.2 months, underscoring its prominence among immuno-oncology combinations at the meeting.5

The sponsor emphasized that these results are exploratory Phase II data, and that future regulatory approvals and commercial outcomes remain uncertain, with typical forward-looking risk factors cited (competition, regulatory changes, development risks, and market conditions).1 2

Sources:

1. https://www.prnewswire.com/news-releases/updated-efficacy-data-of-ivonescimab-combined-with-chemotherapy-as-first-line-treatment-for-tnbc-presented-at-esmo-io-2025-302638641.html

2. https://www.marketscreener.com/news/akeso-inc-announces-updated-efficacy-data-of-ivonescimab-combined-with-chemotherapy-as-first-line-ce7d50dadc8af622

3. https://www.oncozine.com/ivonescimab-to-emerge-as-chinas-first-potential-bispecific-immuno-oncology-therapy-in-tnbc/

5. https://www.lqventures.com/esmo-immuno-oncology-2025-preview/

Sources:

Leave a Reply Cancel reply