Part A will assess the safety and tolerability of SAD of intradermal (ID) injection of AZD8601 (modified VEGF-A RNA) and Part B will evaluate the pharmacodynamic effects of ID injection of AZD8601 in forearm skin. AZD8601 is a VEGF-A modified RNA under development as a novel modality for local production of human VEGF-A protein and is developed for the treatment of diabetic patients with ulcers. Each patient in Part A will be involved in the study for 7 to 8 weeks. Each patient in Part B will be involved in the study for 5 to 6 weeks.