By Fineline Cube 
Multitude Therapeutics, Inc. today released preliminary data from its ongoing Phase I/II, open‑label, multicenter, dose‑escalation and expansion study of AMT‑116, a novel antibody‑drug conjugate (ADC) that targets the CD44v9 onco‑antigen. The data were presented at the European Society for Medical Oncology (ESMO) Congress 2025 in Berlin, Germany.
Study Design & Patient Population
- Phase – I/II, open‑label, multicenter, dose‑escalation + expansion
- Enrollment – 164 subjects (as of July 17 2025)
- Dosing – 1.5 – 5.0 mg/kg Q2W (once every two weeks)
- Cancer Types – EGFR‑wild‑type NSCLC, nasopharyngeal carcinoma, anal squamous cell carcinoma, salivary gland carcinoma
- Line of Therapy – 1–5 prior lines for EGFR‑wild‑type NSCLC patients
Key Efficacy Findings
| Sub‑cohort | Dose | Objective Response Rate (ORR) | Disease‑Control Rate (DCR) |
|---|---|---|---|
| EGFR‑wild‑type NSCLC (≥ 3.0 mg/kg) | 3.0 – 5.0 mg/kg | 40 % (6/15) | 93 % (14/15) |
| EGFR‑wild‑type NSCLC (5.0 mg/kg) | 5.0 mg/kg | 80 % (4/5) | 100 % (5/5) |
| Nasopharyngeal carcinoma (≥ 3.0 mg/kg) | 3.0 – 5.0 mg/kg | 50 % (3/6) | — |
| Anal squamous cell carcinoma (≥ 3.0 mg/kg) | 3.0 – 5.0 mg/kg | 60 % (3/5) | — |
| Salivary gland carcinoma (≥ 3.0 mg/kg) | 3.0 – 5.0 mg/kg | 33 % (2/6) | — |
- CD44v9 Expression – Anti‑tumor activity observed regardless of baseline CD44v9 levels.
- Long‑Term Outlook – Early data suggest durable responses; ongoing follow‑up will clarify survival benefits.
Safety Profile
- Common Treatment‑Related AEs – Manageable hematologic toxicity (e.g., neutropenia, anemia).
- Non‑hematologic AEs – Minimal, low‑grade oral mucosal and skin reactions.
- Overall Tolerability – Consistent with other topoisomerase‑1 (TOP1) inhibitor‑based ADCs; no dose‑limiting toxicities reported to date.
Product Profile – AMT‑116
- Target – CD44v9, a cell‑surface protein overexpressed in solid tumors and implicated in cancer‑stem‑cell signaling.
- Antibody – Proprietary humanized IgG with high affinity for CD44v9.
- Linker – Cleavable, designed for tumor‑specific payload release.
- Payload – Belotecan derivative (KL610023), a potent, clinically validated TOP1 inhibitor.
- Drug‑to‑Antibody Ratio (DAR) – ≈ 7‑8.
Forward‑Looking Statements
The information contained herein includes forward‑looking statements that involve risks and uncertainties. Actual results may differ materially.