The purpose of this study is to learn about the safety and effects of 2 study medicines (PF-07275315 and PF-07264660) for the treatment of atopic dermatitis (AD). AD is a long- lasting itchy red rash, caused by a skin reaction. This study is seeking participants who: * are 18 years of age or more. * Were confirmed to have AD at least 6 months ago. * Are not having an effective treatment result from medicines that are applied on skin for AD. * Are considered by their doctors to have moderate to severe AD. In Stage 1 of the study, participants will receive either PF-07275315 or PF-07264660 or placebo. Stage 1 is complete. In Stage 2 of the study participants will receive either PF-07275315 or placebo. In Stage 3 of the study participants who have received anti-inflammatory proteins, will receive either PF-07275315 or placebo. In Stage 4 of the study participants will receive either PF-07264660 or placebo. A placebo does not have any medicine in it but looks just like the medicines being studied. PF-07275315 or PF-07264660 or placebo will be given as multiple shots in the clinic over the course of each Stage. The experiences of people receiving PF-07275315 or PF-07264660 will be compared to people who do not. This will help determine if PF-07275315 and PF-07264660 are safe and effective. Participants in Stages 1, 2 and 4 will be involved in this study for up to 40 weeks (10 months). Participants in Stage 3 will be involved in this study for up to 52 weeks (13 months).