A Phase 1, First-time-in-human, Three-part Study to Evaluate the Safety, Tolerability, Pharmacokinetics, Pharmacodynamics, and Immunogenicity of GSK4527363 in Healthy Participants (Part A), Participants With Active Systemic Lupus Erythematosus (Part B), Healthy Participants of Chinese and Japanese Descent (Part C) and Participants With Interstitial Lung Disease Associated With Connective Tissue Disease (Part D)
This study will assess the safety, tolerability, pharmacokinetics, pharmacodynamics and immunogenicity of GSK4527363 in healthy participants (Part A), participants with active SLE (Part B), healthy participants of Chinese and Japanese descent (Part C), and participants with interstitial lung disease associated with connective tissue disease (Part D)
⁃ For Part A and Part C (Healthy Participants):
• Participant must be 18 to 55 years of age inclusive, at the time of signing the informed consent form.
• Participants who are overtly healthy as determined by medical evaluation including medical history, physical examination, laboratory tests, and cardiac monitoring (vital signs and 12-lead ECG).
• Part C only: Be of Japanese (Cohort C1) or Chinese (Cohort C2) ancestry. i. Born in Japan (Cohort C1) or China mainland, Hong Kong or Taiwan (Cohort C2); and ii. Descendent of 2 ethnic Japanese (Cohort C1) or Chinese (Cohort C2) parents and 4 ethnic grandparents; and iii. Have lived outside Japan (Cohort C1) or China mainland, Hong Kong or Taiwan (Cohort C2) for less than 10 years at the time of screening.
• Body weight greater than or equals to (\>=) 45 kilograms (kg).
• Body mass index (BMI) within the range 18-32 kilograms per square meter (kg/m\^2) (inclusive).
• Male or female of non-childbearing potential
⁃ For Part B (SLE participants):
• 18 to 65 years of age inclusive, at the time of signing the informed consent form
• Documented clinical diagnosis of SLE according to the (European alliance of associations of rheumatology \[EULAR\]/ American College of Rheumatology \[ACR\] SLE classification criteria)
• Body weight \>= 45 kg.
• BMI within the range 18-32 kg/m\^2 (inclusive).
• Male or female
• Capable of giving signed informed consent For Part D (CTD-ILD Participants)
• Participants must be 18 to 65 years of age, at the time of signing the informed consent form.
• Documented clinical diagnosis of Rheumatoid arthritis (RA), Systemic sclerosis (SSc), Idiopathic inflammatory myopathy (IIM); including polymyositis, dermatomyositis, antisynthetase syndrome, Primary Sjogren's syndrome (pSS) or mixed connective tissue disease (MCTD) in accordance with internationally recognised classification criteria
• Documented clinical diagnosis of interstitial lung disease (ILD) as determined by historical High-resolution computed tomography (HRCT)
• Participants must be on a stable dose of therapy to manage ILD and/or underlying connective tissue disease (CTD)
• Participant has an area of skin that, in the opinion of the Investigator, would allow Subcutaneous (SC) administration of study intervention according to the protocol
• Participants must be current for all vaccinations in accordance with local guidelines, within a year of, and at least 30 days before, first dose. If local guidelines recommend seasonal influenza vaccine, this need only be administered during Flu season (October to April)
• Body weight \>= 45 kg
• BMI within the range 18-32 kg/m\^2 (inclusive)
• Male or female