A clinical study to evaluate the effects of RO7795068 in participants with obesity or overweight without type 2 diabetes

1. Why is this study needed?

Obesity is a complex, long-term medical condition that can lead to various health problems, including issues with physical function and mental health. Many different factors contribute to obesity or overweight, such as genetics, biology, the environment a person lives in, and their socio-economic situation.There is still a need for more treatment options that help people reach a healthier weight and are easier to tolerate.

This study is testing a medicine called RO7795068. It is being developed to treat obesity or overweight.

RO7795068 is an experimental medicine. This means health authorities (like the U.S. Food and Drug Administration and European Medicines Agency) have not approved RO7795068 for the treatment of obesity or overweight.

This study aims to compare the effects of RO7795068 against non-active medicine (placebo) in people living with obesity or overweight.

2. Who can take part in the study?

People (males / females) who are 18 years or older with obesity or overweight can take part in the study if they have a body mass index (BMI) of 30 kg/m² or higher. BMI is a measure used to assess whether a person’s weight is healthy for their height. People with a BMI between 27 and 30 kg/m² can also take part if they have at least one of the following health problems: higher-than-normal blood sugar level (prediabetes), high blood pressure, high cholesterol, breathing problems during sleep, or certain types of heart disease.

People may not be able to take part in this study if they have a history of diabetes or have recently gained or lost a lot of weight (more than 5 kg in the last 3 months). People whose weight is affected by certain medical conditions or genetic disorders, or who have received certain weight loss treatments in the last 6 months will also not be able to take part.

People who are pregnant, planning to get pregnant, or currently breastfeeding cannot take part in the study.

3. How does this study work?

People will be screened to check if they are able to participate in the study. The screening period will take place for about 4 weeks before the start of treatment.

Everyone who joins this study will be randomly split up into 4 groups of about the same size (like rolling a die) and self-administer either:

1. Non-active medicine (placebo), given as an injection under the skin (subcutaneous injection), once every week for 72 weeks
2. RO7795068 (low dose), given as an injection under the skin, once every week for 72 weeks
3. RO7795068 (medium dose), given as an injection under the skin, once every week for 72 weeks
4. RO7795068 (high dose), given as an injection under the skin, once every week for 72 weeks

Participants will have an equal chance of being placed in any of the 4 groups.

This is a ‘placebo-controlled’ study. This means that participants are put in a group that will receive an active medicine or a group that will receive ‘placebo’ (a medicine that contains no active ingredients but looks the same and is taken in the same way as the study medicine). Comparing results from the different groups helps researchers know if any changes seen result from the study medicine or occur by chance. 

This is a double-blinded study. This means that neither the participants in the study nor the team running it will know which treatment is being given until the study is over. This is done to make sure that the results of the treatment are not affected by what people expect from the treatment they receive. However, the study doctor can find out which group a participant is in, if the participants' safety is at risk.

During this study, the study doctor will see participants every 4 weeks for the first 36 weeks and then every 12 weeks thereafter. They will perform assessments to understand how well the treatment is working and note any unwanted effects participants may have. After completing the main treatment period, all participants will have the option to take part in an extension of the study. Participants will have 1 follow-up visit 4 weeks after their last dose, during which the study doctor will check on the participants and look for any unwanted effects. The total time of participation in the study will be about 1.5 years. Participants have the right to stop study treatment and leave the study at any time, if they wish to do so.

4. What are the main results measured in this study?

The main results measured in the study to assess if the medicine has worked are the percentage change in the body weight from the start of the study to week 72. Other key results measured in the study include:

• The number of participants who achieve various levels of weight loss (5%, 10%, 15%, 20%, and 25%) by week 72
• Changes in body weight (in kilograms) by week 72
• Changes in waist size by week 72
• Changes in measures related to metabolism (fasting blood sugar and insulin) by week 72
• Changes in measures related to the heart (cholesterol, triglycerides, and blood pressure), and ability to do daily activities by week 72

5. Are there any risks or benefits in taking part in this study?

Taking part in the study may or may not make participants feel better. But the information collected in the study may help other people with similar health conditions in the future. 

It may not be fully known at the time of the study how safe and how well the study treatment works. The study involves some risks to the participant. But these risks are generally not greater than those related to routine medical care or the natural progression of the health condition. People interested in taking part will be informed about the risks and benefits, as well as any additional procedures or tests they may need to undergo. All details of the study will be described in an informed consent document. This includes information about possible effects and other options of treatment.

Risks associated with the study medicine
Participants may have unwanted effects from the medicine used in this study. These unwanted effects can be mild to severe, even life-threatening, and vary from person to person. During this study, participants will have regular check-ups to see if there are any unwanted effects.

RO7795068 has had limited testing in humans. Therefore, the unwanted effects of this medicine are not known now. Participants will be told about the possible unwanted effects based on laboratory studies or knowledge of similar medicines. Possible unwanted effects include wanting to throw up, throwing up, loose, watery [and more frequent] stools, inflammation of pancreas, gall bladder and/or bile ducts and low blood sugar levels.

RO7795068 and placebo will be self-administered as an injection under the skin. Known unwanted effects of injection include reactions at the injection site, such as bruising (dark purple or blackish in colour), swelling, and itching.

The study medicine(s) may be harmful to an unborn baby. Women must take precautions to avoid exposing an unborn baby to the study treatment.