A two-part, randomised, double-blind, placebo-controlled, parallel-group, 12 week trial investigating the safety, tolerability, pharmacokinetics and efficacy of XEN-D0501 in obese participants.

Prior treatment

• Prior or current intake of grapefruit or grapefruit-containing products (refer to Section 9.6.1), or prior or current treatment with CYP3A4 inhibitors (including but not limited ketoconazole, erythromycin, verapamil, fluconazole) as judged by the Investigator.
• Treatment with weight loss agents within 90 days prior to screening or participation in lifestyle weight loss programme.
• Regular use of prescribed or non-prescribed medication within 2 weeks prior to the first administration of IMP as judged by the Investigator. Participants who are on stable treatment with anti-depressants (e.g., selective serotonin re-uptake inhibitors [SSRI]) for at least 2 months can be included at the discretion of the Investigator.
• Positive screening result for drugs of abuse/recreational drugs or alcohol at the screening visit or on admission to the trial site prior to the first administration of the IMP.
• Participation in any other trials involving investigational medicinal products within 3 months prior to the first IMP administration.
• Whole blood or red blood cell donation, or any blood loss > 500 mL during the 3 months prior to screening, or plans to donate blood during the trial.
• Previous participation in this trial (randomisation).
• Any participant could be excluded if, at the discretion of the Investigator, if, based on their medical history or examination, there may be a significantly higher risk to the participant than the general trial population, or if medication or medical history could confound or bias the trial results.
• Any planned major surgery within the duration of the trial, including prior or planned surgical treatment of obesity.

Other illness

• History of any clinically significant disease or disorder which, in the opinion of the Investigator, may either put the participant at risk because of participation in the trial, or influence the results or the participant’s ability to take part in the trial.
• History of significant drug allergies or with a known or suspected allergy to the trial product or any medicine chemically related to the trial product, as judged by the investigator.
• Clinically significant abnormal haematology or biochemistry tests at screening visit, as judged by the investigator considering the underlying disease.
• Any clinically significant illness, medical/surgical procedure or trauma within 4 weeks of the first administration of IMP.
• History of alcohol abuse or excessive intake of alcohol, as judged by the Investigator.
• Presence or history of drug abuse, as judged by the Investigator.
• History of, or current use of anabolic steroids, as judged by the Investigator.
• Type 1 or 2 diabetes.
• Malignancy within the past 5 years, with the exception of in situ removal of basal cell carcinoma.
• Prolonged QTcF (>450 ms), cardiac arrhythmias or any clinically significant abnormalities in the resting ECG at the screening visit, as judged by the Investigator.

Lab values

• Any positive result at the screening visit for serum hepatitis B surface antigen, hepatitis C antibodies and/or human immunodeficiency virus (HIV).
• Haemoglobin < 6.2 mmol/L (<99.8 g/L), total leukocyte count < 3.0 x 109/L, thrombocytes <100 x 109/L at the time of the screening visit.
• Estimated glomerular filtration rate (eGFR) < 60 mL/min, serum creatinine levels ≥ 126 μmol/L (male) or ≥ 111 μmol/L (female) at the time of the screening visit, as judged by the Investigator.
• Bilirubin > 3 x upper limit of normal (ULN), ALT > 2 x ULN, AST > 2 x ULN at the time of the screening visit.
• Prior treatment with glucose-lowering agents that also affect body weight within 3 months prior to the screening visit.
• Current treatment with drugs known to interfere with glucose metabolism such as systemic corticoids and monoamine oxidase inhibitors (MAO) inhibitors.

Other

• Thyroid stimulating hormone (TSH) above the normal range at the time of the screening visit, as judged by the Investigator.
• Current smokers or users of nicotine products. Irregular use of nicotine (e.g., smoking, snuffing, chewing tobacco) less than 3 times/week is allowed before the screening visit.
• Participant who is pregnant, currently breastfeeding, or intends to become pregnant during the course of the trial.
• Mental incapacity or language barriers which preclude adequate understanding or cooperation, unwillingness to participate in the trial, or those in the opinion of the Investigator should not participate in the trial.
• Untreated high blood pressure (systolic blood pressure ≥160 mmHg and diastolic blood pressure ≥100 mmHg) at the time of the screening visit.

• Willing and able to give written informed consent for participation in the trial.
• Male or female participant aged ≥25 years at the time of signing the informed consent form.
• BMI ≥30.0 and ≤39.9 kg/m2 at the time of the screening visit.
• Stable weight in the 3 months preceding the trial (defined as no more than 5% body weight increase or decrease by self-reporting at the screening visit).
• HbA1c < 6.5% (<48 mmol/mol) at the time of the screening visit.
• Women of non-childbearing potential are pre-menopausal females who have undergone any of the following surgical procedures; hysterectomy, bilateral salpingectomy or bilateral oophorectomy, or who are post-menopausal defined as 12 months of amenorrhea (in questionable cases a blood sample with detection of follicle stimulating hormone [FSH] >25 IU/L is confirmatory). Male participants must be willing to use condom or be vasectomised or practice sexual abstinence from heterosexual intercourse (only allowed when this is the preferred and usual lifestyle of the participant) to prevent pregnancy and drug exposure of a partner, and refrain from donating sperm from the first administration of IMP until 4 weeks after the last administration of IMP. Any female partner of a non-vasectomised male participant who is of childbearing potential must use contraceptive methods with a failure rate of <1% per year* to prevent pregnancy from at least 2 weeks prior to the first administration of IMP to 4 weeks after the last administration of IMP. *The following are considered highly effective methods of contraception: • combined (oestrogen and progestogen containing) hormonal contraception associated with inhibition of ovulation (oral, intravaginal, transdermal), • progestogen-only hormonal contraception associated with inhibition of ovulation (oral, injectable, implantable), • intrauterine device (IUD) or intrauterine hormone-releasing system (IUS), • female sterilisation.