In short
OTP-01 is an investigational dual paratopic antibody designed to target both PD-1 and VEGFR2, being studied in advanced solid tumours. It is a protein-based substance given by intravenous infusion, with no marketing authorisation in the product records. One authorised Phase 1/2 trial is investigating its safety, tolerability and preliminary anti-tumour activity in up to 170 participants.
Key points
- OTP-01 is a dual paratopic antibody that blocks both PD-1 and VEGFR2.
- It is being studied in advanced solid tumours in a single Phase 1/2 trial.
- The trial is authorised and plans to enrol up to 170 participants.
- Phase 1 measures safety, tolerability and recommended Phase 2 dose; Phase 2A measures objective response rate and other efficacy endpoints.
- OTP-01 is given by intravenous infusion and has no marketing authorisation.
What is OTP-01?
OTP-01 is an investigational monoclonal antibody classified as an antineoplastic and immunotherapy agent. It is described as a dual paratopic antibody, meaning it is engineered to bind to two different targets at the same time: programmed cell death protein 1 (PD-1) and vascular endothelial growth factor receptor 2 (VEGFR2). The substance is protein-based and is supplied as a solution for injection given by intravenous infusion. OTP-01 has no marketing authorisation in the product records, meaning it remains an investigational substance. The originator of OTP-01 is Ottimo Pharma.
How does OTP-01 work?
OTP-01 works through two mechanisms of action. It acts as a PD-1 receptor antagonist, which means it blocks the PD-1 checkpoint that cancer cells can use to switch off the immune system. By blocking PD-1, OTP-01 helps T lymphocytes — the immune cells that attack cancer — to stay active. At the same time, OTP-01 acts as a VEGFR2 antagonist, blocking the receptor that tumours use to grow new blood vessels. This may help starve the tumour of its blood supply. The antibody is also designed to trigger antibody-dependent cell cytotoxicity, a process by which immune cells destroy antibody-coated cells.
Which conditions is OTP-01 studied for?
- Advanced solid tumours — cancers that have formed solid masses and have spread or cannot be removed by surgery. The current trial includes various types of advanced solid tumours.
How is OTP-01 given?
OTP-01 is given as a solution for injection by intravenous infusion, meaning it is delivered directly into a vein over a period of time. The trial record does not report a specific dose, as the Phase 1 part of the study is designed to find the recommended Phase 2 dose.
What do the clinical trials show?
There is one authorised Phase 1/2 trial of OTP-01 in advanced solid tumours, planning to enrol up to 170 participants. The trial is interventional and is currently in the authorised status, meaning it has received regulatory approval to proceed.
What is the trial measuring?
In Phase 1, the trial measures safety and tolerability, including the frequency and severity of adverse events and serious adverse events. It also measures pharmacokinetics — how the drug is absorbed, distributed and cleared from the body — and pharmacodynamics, which looks at the drug's biological effects. The main goal of Phase 1 is to determine the recommended Phase 2 dose (RP2D). In Phase 2A, the trial measures preliminary anti-tumour activity using RECIST v1.1, a standard way of assessing whether tumours shrink, stay the same or grow. The main Phase 2A endpoints are objective response rate (ORR) — the proportion of participants whose tumours shrink by a defined amount — and duration of response (DOR), disease control rate (DCR) and progression-free survival (PFS), which is the time without the cancer getting worse. Safety and tolerability continue to be measured in Phase 2A.
Who can take part in this trial?
The trial enrols participants with advanced solid tumours. The registry record does not list detailed eligibility criteria such as age limits or specific tumour types, so the exact inclusion and exclusion criteria would need to be checked in the trial protocol.
What side effects are known?
The available sources do not report specific side effects for OTP-01. The Phase 1 part of the current trial is designed to characterise the safety and tolerability of OTP-01, including the frequency and severity of adverse events and serious adverse events, so safety information will emerge as the trial progresses.