In short
IPN01203 is an investigational protein-based medicine being studied in adults with locally advanced or metastatic solid tumours who have already received immune checkpoint inhibitor therapies. A single Phase 1/2 trial (2025-522184-15-00) is currently authorised, planning to enrol 38 participants. The trial will assess safety, tolerability, how the body processes the drug, and early signs of anti-tumour activity.
Key points
- IPN01203 is an investigational protein-based substance given by intravenous (IV) infusion.
- It is being studied in a single Phase 1/2 trial in adults with locally advanced or metastatic solid tumours.
- The trial is currently authorised and plans to enrol 38 participants.
- Participants must have previously received immune checkpoint inhibitor therapies.
- The study measures safety, tolerability, pharmacokinetics, immunogenicity and objective response rate (ORR).
- IPN01203 has no marketing authorisation and remains an investigational substance.
What is IPN01203?
IPN01203 is an investigational protein-based substance being developed for the treatment of cancer. It is not an authorised medicine: the product records show no marketing authorisation, meaning it cannot yet be prescribed outside of clinical trials. The substance is supplied by Ipsen Pharma and is known only by its development code, IPN01203. It is classified under the therapeutic area of neoplasms, which refers to cancers and tumours.
How does IPN01203 work?
The registry data do not describe the exact molecular target or mechanism of action of IPN01203. As a protein-based substance given by infusion, it is a biological medicine rather than a small-molecule chemical drug. The trial is designed to measure pharmacodynamics — the effects the drug has on the body — as well as immunogenicity, which is whether the body produces an immune response against the drug itself. Further details on the mechanism of action are not provided in the available sources.
Which conditions is IPN01203 being studied for?
- Advanced solid tumours — cancers that have grown locally or spread to other parts of the body and are no longer considered early-stage.
- Metastatic solid tumours — solid tumours that have spread from the original site to distant organs.
The trial focuses on participants whose disease has already been exposed to immune checkpoint inhibitor therapies, a type of cancer treatment that helps the immune system attack cancer cells.
How is IPN01203 given?
IPN01203 is given as a solution for infusion, administered directly into a vein (intravenous or IV infusion). No other pharmaceutical forms, such as tablets or injections under the skin, are listed in the available data.
What do the clinical trials show?
One trial is registered for IPN01203: a combined Phase 1/2 study (EU CT number 2025-522184-15-00) that is currently authorised, meaning it has received regulatory approval to begin but is not yet reporting results. The trial plans to enrol 38 adults with locally advanced or metastatic solid tumours who have previously received immune checkpoint inhibitor therapies.
The study is divided into two parts. Phase Ia aims to evaluate the safety and tolerability of IPN01203 as a single agent and to determine the maximum tolerated dose (MTD) or maximum administered dose (MAD). Phase Ib aims to determine the optimal dosing regimen in selected tumour types.
The primary outcome measures include the percentage of participants experiencing dose-limiting toxicity (DLT), treatment-emergent adverse events (TEAEs) and treatment-emergent serious adverse events (TE SAEs). In Phase Ib, the objective response rate (ORR) is also measured — this is the percentage of participants whose tumours shrink completely (complete response) or partially (partial response), as assessed by the investigator using RECIST version 1.1 criteria. The study also evaluates pharmacokinetics, which describes how the body absorbs, distributes, breaks down and eliminates the drug.
What side effects are known?
The available registry data do not list specific side effects for IPN01203. The trial is designed to identify side effects: it measures dose-limiting toxicities, treatment-emergent adverse events and serious adverse events as primary outcomes. As an investigational substance with no published safety information, the side effect profile is not yet known.