Research Studies

Laboratory-confirmed or presumptive HMPXV infection: Presumptive diagnosis: Skin lesion(s), mucosal lesion(s) or proctitis consistent with a high probability of HMPXV in the opinion of the site investigator AND &#8226; Sexual contact with 1 or more persons in the 21 days prior to symptom onset or close exposure to another person known to be infected with HMPXV. HMPXV illness of <14 days duration immediately prior to study entry. At least one active (not yet scabbed) skin lesion, mouth lesion, or proctitis with or without visible ulcers. Non-pregnant people of reproductive potential must agree to use at least one effective means of contraception when engaging in sexual activities that can result in pregnancy, from the time of enrollment through the end of study participation. Acceptable methods of contraception. Ability to provide informed consent (for those above the legal age of consent and those providing consent for minors) and assent (for those over the age of 7, but below the legal age of consent)

SELECTION AND ENROLLMENT OF PARTICIPANTS 4.1 Inclusion Criteria (All participants; Arms A, B, and C) 4.1.1 Laboratory-confirmed or presumptive HMPXV infection: Laboratory-confirmed HMPXV infection is defined as determined by PCR, culture, or antigen test obtained from a sample collected from a skin lesion, oropharynx, or rectal swab obtained within 7 days prior to study entry OR Presumptive diagnosis: • Skin lesion(s), mucosal lesion(s) or proctitis consistent with a high probability of HMPXV in the opinion of the site investigator AND • Sexual contact with 1 or more persons in the 21 days prior to symptom onset or close exposure to another person known to be infected with HMPXV. 4.1.2 HMPXV illness of <14 days duration immediately prior to study entry. 4.1.3 At least one active (not yet scabbed) skin lesion, mouth lesion, or proctitis with or without visible ulcers. 4.1.4 Non-pregnant people of reproductive potential must agree to use at least one effective means of contraception when engaging in sexual activities that can result in pregnancy, from the time of enrollment through the end of study participation. Acceptable methods of contraception include the following: • Abstinence • Hormonal contraception • Male or female condom • Diaphragm or cervical cap with a spermicide • Intrauterine device 30 A5418 FINAL Version 2.0 25Aug2022 NOTE: Reproductive potential is defined as: • Participants who have reached menarche • Participants who have not been post-menopausal for at least 12 consecutive months with follicle-stimulating hormone (FSH) ≥40 IU/mL or 24 consecutive months if an FSH is not available • Participants who have not undergone surgical sterilization (e.g., hysterectomy, bilateral oophorectomy, bilateral tubal ligation, or bilateral salpingectomy) • For individuals with permanent infertility due to an alternate medical cause (e.g., Mullerian agenesis, androgen insensitivity), investigator discretion should be applied to determining study entry. 4.1.5 Ability to provide informed consent (for those above the legal age of consent and those providing consent for minors) and assent (for those over the age of 7, but below the legal age of consent) 4.2 Additional Inclusion Criteria for Arms A and B 4.2.1 Age ≥18 years at the time of study entry 4.3 Additional Inclusion Criteria for Arm C Participants who meet the above entry criteria (section 4.1) who also meet any of the following criteria will be registered to Arm C. 4.3.1 Participants age <18 years at the time of study entry 4.3.2 Those with severe HMPXV disease defined as having one or more of the following conditions: • Suspected or confirmed ocular involvement • Facial lesions on the malar, nose, or eyelid region • Confluent facial lesions • Hospitalization due to HMPXV infection or its complications • Lesions that require surgical intervention including debridement, urinary catheterization or sigmoidoscopy, or lesions extending below the dermis Those with or without severe disease and with one or more of the following will also be enrolled into Arm C: • Severe immunosuppression defined as: o HIV with CD4 <200 cells/mm3 or plasma HIV-1 RNA >1000 copies/mL o Leukemia o Lymphoma o Generalized malignancy o Solid organ transplantation o Therapy with alkylating agents within 180 days prior to study entry o Antimetabolites within 180 days prior to study entry 31 A5418 FINAL Version 2.0 25Aug2022 o Radiation therapy within 180 days prior to study entry o Tumor necrosis factor inhibitors within 180 days prior to study entry o High-dose corticosteroids (equivalent of 20 mg or greater of prednisone for at least 14 days) within 90 days prior to study entry o Being a recipient with hematopoietic stem cell transplant <24 months post-transplant or ≥24 months but with graft-versus-host disease or diseas