Evaluation of Dextromethorphan as a Microglia Inhibitor in the treatment of DME

五名参与者将被纳入这项公开的试点研究。然而，在接受6个月的研究治疗之前退出研究的参与者中，最多可以再招收3名参与者。参与者将口服60毫克右美沙芬，每天两次，持续24个月。在每次访问期间，参与者将测量他们的视力并进行OCT测试以测量视网膜厚度。从第4个月就诊开始，将对患者进行疾病恶化评估，定义为与基线相比，ETDRS视力损失15个字母或oct测量的视网膜总厚度增加50%。此外，从第6个月就诊开始，参与者将有资格接受病灶激光治疗，除非他们的视网膜厚度和/或视力有明显改善，或者他们不适合病灶激光治疗。不符合改善标准的参与者也将有资格接受抗血管内皮生长因子（VEGF）治疗，如贝伐单抗或雷尼单抗。被认为病情恶化的参与者也将有资格接受局部激光和/或抗vegf治疗。

Five participants will be initially enrolled in this unmasked pilot study. However, up to an additional three participants may be enrolled to account for participants who withdraw from the study prior to receipt of six months of study treatment. Participants will take an oral dose of 60 mg of dextromethorphan twice daily for 24 months. During each visit, participants will have their visual acuity measured and will undergo OCT testing to measure retinal thickness. Beginning at the Month 4 visit, participants will be assessed for worsening disease defined as loss of 15 ETDRS letters of vision compared to baseline or a 50% increase in total retinal thickness as measured by OCT. Additionally, beginning at the Month 6 visit, participants will be eligible for focal laser therapy unless they show marked improvement in retinal thickness and/or visual acuity or if they are not amenable to focal laser treatment. Participants who do not meet the criteria for improvement will also be eligible for anti-vascular endothelial growth factor (VEGF) treatments such as bevacizumab or ranibizumab. Participants deemed to have worsening disease will also be eligible for focal laser and/or anti-VEGF treatments. The primary outcome is the change in best-corrected visual acuity (BCVA) in the study eye at six months compared to baseline. Secondary outcomes include the change in retinal thickness as measured by OCT at 6, 12, 18 and 24 months compared to baseline, change in BCVA at 12, 18 and 24 months compared to baseline, change in mean macular sensitivity as measured by microperimetry at 6, 12, 18 and 24 months compared to baseline, as well as changes in fluid leakage in the macula as demonstrated by fluorescein angiography at 6, 12, 18 and 24 months compared to baseline. Safety outcomes include the number and severity of systemic and ocular toxicities, and adverse events.