21 Characteristics of KSI-301 We believe that KSI-301 can be a highly differentiated treatment with an improved durability and bioavailability profile compared to current anti-VEGF therapies due to the following design features and resulting performance benefits we have observed with KSI-301 in our preclinical development: • Design feature: KSI-301’s ultra-high molecular weight of 950,000 Daltons as compared to 115,000 for EYLEA, 48,000 for Lucentis and 27,000 for brolucizumab • Associated performance benefits: • 4x improvement in key ocular pharmacokinetic parameters of KSI-301, as compared to ranibizumab • >100x ocular concentration advantage at two months post-dosing of KSI-301, as compared to the standard of care anti-VEGF agents • Design feature: KSI-301’s phosphorylcholine-based ABC Platform • Associated performance benefits: • 4x increase in key target ocular tissue bioavailability, as compared to EYLEA • Same or increased bioactivity, as compared to the standard of care anti-VEGF agents • Increased stability and resistance to degradation of bioconjugates compared to therapeutic proteins • Design feature: KSI-301’s increased formulation strength of 50 mg/mL as compared to 40 mg/mL for EYLEA and 10 mg/mL for Lucentis, as measured by weight of protein moiety • Associated performance benefits: • 3.5x and 7x higher number of anti-VEGF binding sites per dose, as compared with EYLEA and Lucentis, respectively We believe that the aggregated effects of these properties could afford KSI-301 a longer on-mechanism durability that will more closely match the frequency of physician visits that is realistic for patients in clinical practice. We also believe that these properties along with KSI-301’s delivery by intravitreal injection position it favorably compared to other therapies being studied in the clinic with the aim of long-interval dosing in retinal vascular disease. For example, both gene therapy and an implantable drug reservoir require the patient to undergo surgery, which is generally riskier than an intravitreal injection. This need for surgery may reduce the likelihood that those technologies could be useful for or adopted by a broad range of physicians and patients, especially those patients with earlier-stage disease. An implantable drug reservoir also leaves a foreign body permanently in the eye, with an attendant increased risk of infection. Coated microsphere drug depots that deliver small-molecule receptor tyrosine kinase inhibitor drugs into the eye may leave a foreign residual material, which may cause visual symptoms and/or other safety problems. Additionally, receptor tyrosine kinase inhibitor drugs affect signaling through additional receptors other than VEGF receptor; the effects on the eye of this additional receptor inhibition, either good or bad, are not yet known. Finally, bispecific antibodies that target VEGF as well as other angiogenic signaling pathways are attempting to increase durability of treatment effect through targeting of yet- unvalidated biologic pathways, but the antibodies being used are the same size as typical monoclonal antibodies (~150 kDa) and we believe they do not have any unique size or half-life extending properties.