This study will evaluate the safety and tolerability of SLN124 in healthy volunteers.

This first-in-human (FIH) study will investigate the safety, tolerability, pharmacokinetics (PK) and pharmacodynamics (PD) of SLN124 after single ascending s.c. doses in healthy male and female subjects.

Up to 3 cohorts of 24 healthy volunteers will be enrolled. Each subject will receive a single dose of SLN124 or placebo given by subcutaneous (s.c) injection.

Inclusion Criteria:

• Normotensive male or female volunteers, with a body mass index of 18.0-30.0 kg/m2.
• Deemed healthy on the basis of a clinical history, physical examination, ECG, vital signs, and laboratory tests of blood and urine.
• Agree to follow the contraception requirements of the trial.
• Able to give fully informed written consent.
• Agree not to donate blood or blood products during the study and for up to 3 months after the administration of the trial medication.

Exclusion Criteria:

• History or presence of iron deficiency or iron deficiency anaemia and/or currently receiving oral or parenteral iron supplementation as treatment for those conditions.
• Positive tests for hepatitis B & C, HIV
• Drug or alcohol abuse.
• Smoke more than 10 cigarettes (or equivalent) daily.
• Use of over-the-counter medication (with the exception of paracetamol [acetaminophen]) during the 7 days before the first dose of trial medication, or prescribed medication (with the exception of hormone replacement therapy [HRT]) during the 28 days before first dose of trial medication.
• Use of supplement(s) during the 28 days before screening.
• Participation in other clinical trials of unlicensed medicines, or loss of more than 400 mL blood, within the previous 3 months.
• Clinically relevant abnormal medical history or concurrent medical condition.
• Pre-menopausal females who are pregnant or lactating, or who are sexually active and not using a reliable method of contraception.