The Sponsor judged that the objectives of this Phase 1 study were satisfied, and the study was terminated after the completion of Cohort 3 Step 3.

The purpose of this study is to evaluate safety and tolerability after administration of KHK4951 in healthy volunteers and patients with wet age-related macular degeneration.

Inclusion Criteria: Healthy Volunteers

• Voluntary written informed consent to participate in the study
• Japanese or white men 20 to < 50 years at the time of informed consent
• BMI 18.5 to < 30.0 at screening
• Intraocular pressure (study eye) 10.0 mm Hg to 21.0 mm Hg
• Monocular or binocular visual acuity (corrected visual acuity if correction is required) ≥ 1.0 at screening

Inclusion Criteria: Patients

• Voluntary written informed consent to participate in the study
• Age ≥ 50 years at the time of informed consent
• AMD-associated by active subfoveal CNV lesions in the study eye or juxtafoveal CNV lesions with CNV-associated findings in the fovea in the study eye
• CST ≥ 300 μm in the study eye at screening, as measured by OCT
• BCVA score ≥ 23 letters in the study eye at screening and enrollment, as measured by the ETDRS visual acuity chart
• BCVA score ≥ 58 letters in the non-study eye at screening, as measured by the ETDRS visual acuity chart
• In subjects with prior treatment of the study eye with anti-vascular endothelial growth factor (anti-VEGF) drugs such as Beovu, Eylea, Lucentis, Avastin, or Macugen, presence of response to the anti-VEGF drug(s) as judged by the investigator or subinvestigator based OCT, FA, visual acuity, or other assessment results

Exclusion Criteria: Healthy Volunteers

• Current illness requiring treatment
• History of ophthalmologic laser surgery, ophthalmologic surgery, nasolacrimal duct surgery, orany eyelid surgery affecting flow in the nasolacrimal duct
• History of or current circulatory disease (e.g., cerebrovascular or cardiovascular disease)
• History of or current dry eye
• Abnormal findings on OCT at screening or enrollment examination

Exclusion Criteria: Patients

• Clinical findings or a history of conditions other than wAMD affecting the retina and choroid (e.g., diabetic retinopathy, diabetic macular edema, myopic CNV, retinal vein occlusion, or premacular membrane) in either of the eyes

• Any of the following diseases in the study eye:

  • Glaucoma
  • Ischemic optic neuropathy
  • Retinitis pigmentosa

• Current or history of vitreous hemorrhage or macular hole in the study eye

• Any abnormality in the anterior segment of the eye or vitreous body that may affect fundus observation by OCT, color fundus photography, or fluorescein angiography