A First Time in Human Study to Evaluate the Safety and Tolerability of GSK3996401 Following Dosing With GSK4347859 in Healthy Participants

Inclusion Criteria: * Participants who are overtly healthy. * Participant has a confirmed positive vaccination status for severe acute respiratory syndrome-related Coronavirus (2 SARS-CoV-2) and, if study dosing is during Flu season, influenza vaccines administered at least 30 days prior to dosing in the study. * Fitzpatrick skin type I, II or III (Part 2 only). * Body weight greater than or equal to (≥) 50 kilogram (kg) and body mass index (BMI) within the range 18 -32 kilogram per meter square (kg/m\^2) (inclusive). * Male and female of non-childbearing potential. * Capable of giving signed informed consent. Exclusion Criteria: * History or presence of cardiovascular, respiratory, hepatic, renal, gastrointestinal, endocrine, hematological, psychiatric, or neurological disorders. - Abnormal blood pressure * A clinically significant ECG abnormality at screening. * Evidence of active or latent tuberculosis (TB). * Symptomatic herpes zoster within 3 months prior to screening * Alanine transaminase (ALT) \>1 times upper limit of normal (ULN). * Total bilirubin \>1.5x ULN \[isolated total bilirubin \>1.5x ULN is acceptable if total bilirubin is fractionated and direct bilirubin \<35- percentage (%)\]. * History of malignancy. * Participants with known Corona virus disease-2019 (COVID-19) positive contacts as per local/site Guidelines * Prior moderate/severe COVID-19 infection requiring oxygen supplementation or admission to hospital. * Live vaccine(s) within 1 month prior to screening or plan to receive such vaccines during the study. * Past or intended use of over-the-counter or prescription medication including herbal medications within 7 days prior to dosing * The participant has participated in a clinical trial and has received an investigational product within 30 days, 5 half-lives or twice the duration of the biological effect of the investigational product and dosing. * Current enrolment or past participation in this clinical study * Presence of Hepatitis B surface antigen (HBsAg) at screening or within 3 months prior to first dose of study intervention * Positive hepatitis C antibody test result at screening or within 3 months prior to first dose of study intervention * Positive hepatitis C Ribonucleic acid (RNA) test result at screening or within 3 months prior to first dose of study * Positive pre-study drug/alcohol screen * Regular use of known drugs of abuse, including tetrahydrocannabinol. * Positive Human immunodeficiency virus (HIV) antibody test * Positive smoke breathalyzer levels indicative of smoking history at screening and each in-house admission to the clinical research unit or regular use of tobacco- or nicotine-containing products within 6 months prior to screening. * Estimated glomerular filtration rate (eGFR) of less than (\<) 90 (millilitre/minute) mL/min/1.73 m2 and / or Urine Albumin Creatinine (UACR) of \>30 milligram per gram (mg/g) at screening * A positive confirmation of SARS-CoV-2 infection or signs and symptoms suggestive of SARS-CoV-2 at screening or pre-dose * The participant has a phobia to needles * An average weekly alcohol intake of \> 14 units. For Part 2: * History of benign skin conditions including but not limited to photosensitivity, atopic dermatitis, chronic eczema, psoriasis, urticaria, vitiligo, post-inflammatory hyperpigmentation, or keloid or hypertrophic scaring that in the opinion of the Investigator would impact study participation. * History or presence of excessive bleeding or coagulation disorders. * History of adverse reaction to local anesthetic. * The presence of widespread acne, freckles, naevi, tattoos, birthmarks, piercings, scarring or other skin variations within the proposed Ultraviolet B (UVB) exposure challenge area * Direct UV exposure to the areas of the body to be studied within 2 weeks. * Unable to refrain from exposure to extended and direct sunlight or use of artificial tanning devices, self-tanning products, sun blocking products or other topical products (including moisturizers and makeup) on the areas of the body to be studied.