An Open-label Phase 1 Imaging Study to Evaluate the Biodistribution, Dosimetry, Safety and Pharmacokinetics of BAY 3630942, a 89Zr-labeled Monoclonal Antibody, With a Pre-infusion of BAY 3547922, a Monoclonal Antibody-chelator Conjugate, in Patients With Hepatocellular Carcinoma or Other Select Solid Tumors.

Researchers are studying a new potential treatment for liver cancer or other select solid cancers.

To do this, researchers have developed a protein, called a monoclonal antibody, which can find and attach itself to another protein present on the surface of cancer cells. This can help the new treatment to specifically target cancer cells.

In this study, researchers want to understand the distribution and processing of this monoclonal antibody in people with liver cancer or other select solid cancers.

Researchers will use the following two forms of monoclonal antibody as study interventions during this study:

• BAY3630942: This is the monoclonal antibody attached to a tracer. A tracer emits radiation that can help researchers track the monoclonal antibody in the body using imaging tests like PET/CT (positron emission tomography / computed tomography). All participants will receive a fixed dose of BAY3630942 during the study.
• BAY3547922: This is the monoclonal antibody without the tracer. Participants may receive different amounts of BAY3547922 during the study.

In this study, participants will not derive therapeutic benefit from receiving BAY3630942 or BAY3547922. However, this study may help researchers develop a new treatment for people with liver cancer or other select solid cancers and find a dose to be tested in future studies.

The main purpose of this first-in-human study is to check how BAY3630942 distributes among different organs in the body and how much of the radiation it emits is absorbed by the organs based on the total dose of BAY3630942 and BAY3547922 given. For this, the researchers will:

• measure the amount of BAY3630942 radiation found in different organs over time.
• measure the amount of BAY3630942 radiation absorbed by different organs.
• use the above information to estimate the amount of radiation that would be absorbed by the same organs from the new potential treatment.

Researchers will also monitor the number and severity of medical problems participants have after receiving BAY3630942 and BAY3547922. These medical problems are also known as "adverse events". Doctors keep track of all medical problems that happen in studies, even if they do not think they might be related to the study interventions.

The study participants will first receive BAY3547922 as an infusion into a vein followed by BAY3630942 as an injection into the same vein. Both interventions will be administered only once, on the same day.

Each participant will be in the study for around 44 days with up to 7 visits to the study clinic which includes:

• a visit up to 14 days before the start of the study to confirm if the participant can take part in the study.

• up to 5 visits during the imaging intervention period. During this period, participants:

• will receive the study interventions and have blood tests on the first visit,

• will have imaging and blood tests on the next 3 visits. The tests scheduled for the second visit may be performed during the first visit.

• may have blood tests on the last visit.

• a follow-up visit to check their health after 30 days of receiving the study interventions.

During the study, the doctors and their study team will:

• check participants' health by performing tests such as blood and urine tests, and check heart health using an electrocardiogram (ECG)
• track and study BAY3630942 using PET/CT imaging tests

As the study interventions are not yet treatments for liver cancer or other select solid cancers, access to BAY3630942 and BAY3547922 after the end of the study will not be required.