The study is testing a new medicine for weight control in people with overweight or obesity. The aim of the study is to find out how safe the study medicine is and how it works in the body. Participants will either get NNC9204-1706 (the new study medicine) or placebo (a dummy medicine) - which treatment participants get is decided by chance. NNC9204-1706 is a new medicine which cannot be prescribed by doctors. Participants will get an injection under the skin of participants' stomach each morning for 10 weeks. A medical tool called NovoPen®4 will be used for the injection. Participants must change the part of the pen including the medicine (the cartridge) each day. The study will last for about 16 weeks. Participants will have at least 17 clinic visits and 10 phone calls with the study doctor. At certain times during the study, participants will have blood drawn and 3 different kinds of heart tests (electrocardiograms). Study doctor will ask participants to answer mental health surveys.

Inclusion Criteria:

• Male or female, aged 18-55 years (both inclusive) at the time of signing informed consent.
• Body mass index (BMI) between 25.0 and 39.9 kg/m^2 (both inclusive) at screening. Overweight should be due to excess adipose tissue, as judged by the investigator.

Exclusion Criteria:

• Female subject who is of childbearing potential (pre-menopausal and not surgically sterilised) and is sexually active with male partner(s) who are not surgically sterilised (vasectomy) or who is not using highly effective contraceptive methods (Pearl Index less than 1%) combined with a highly effective method of contraception for their male partner(s) (e.g. condom with spermicide), or are pregnant, breast-feeding or intend to become pregnant.
• Male subject who is not surgically sterilised (vasectomy) and is sexually active with female partner(s) and who is not using a highly effective method of contraception (such as condom with spermicide) combined with a highly effective method of contraception for their nonpregnant female partner(s) (Pearl Index less than 1%), and/or intend to donate sperm in the period from screening until 90 days following administration of the investigational medical product.
• Any disorder which in the investigator's opinion might jeopardise subject's safety, evaluation of results, or compliance with the protocol.

According to the Novo Nordisk disclosure commitment on novonordisk-trials.com

Sponsor staff involved in the clinical trial is masked according to company standard procedures.