Nanocrystalline Gold to Treat Remyelination Failure in Chronic Optic Neuropathy In Multiple Sclerosis

This is a randomized, double-blind, parallel-group, placebo-controlled study of the efficacy, safety, and pharmacokinetics of CNM-Au8 in stable RRMS patients who have Chronic Optic Neuropathy evidence by low contrast letter acuity deficits at Screening. Patients will be screened over a 6-week period. Patients who meet the inclusion criteria and none of the exclusionary criteria will be enrolled into the clinical study. All enrolled patients will have their visual baseline established in both eyes by functional, electrophysiological (at participating research sites), and morphological tests. For each patient, the eye with the worst Baseline LCLA score will be considered as the affected eye. The other eye will be considered as the fellow eye. If both eyes have the same LCLA score at Baseline, then one eye will be randomly selected by the statistician to assess as the designated affected eye. Efficacy endpoints will be assessed in both the affected and the fellow eyes. Patients will be randomized to one of three groups: placebo, or one of two doses of CNM-Au8. All patients will receive their randomized investigational product (IP) dose daily over at least 24 consecutive weeks during the Fixed Duration Treatment Period. The study will also have a blinded Variable Duration Treatment Period for up to an additional 24-weeks (up to a 48-week maximum blinded duration) until the last-patient enrolled completes his/her Week 24 study visit per the study scheme in Figure 2. When the last enrolled patient completes his or her Week 24 visit, patients enrolled in the Variable Duration Treatment Period will complete the End-of-Study (EOS) visit at their next scheduled study visit. The primary efficacy outcome measure will be assessed Efficacy will be assessed as an improvement in best-corrected low contrast letter acuity (BC-LCLA). Safety will be assessed up through the frequency of treatment-emergent adverse events (TEAEs), serious adverse events (SAEs), and discontinuations due to adverse events (AEs), and changes in safety assessments (e.g., vitals, ECG, C-SSRS). The study will remain blinded until the study database is locked. All patients who are discontinued from treatment will complete the End-of-Study (EOS) assessment. At the end of the Variable Duration Treatment Period, patients will complete an EOS assessment and then may choose either to exit the study, or receive open-label CNM-Au8 in a separate Open-Label Safety Extension Study. An independent DSMB will be responsible for monitoring the safety of the study on a quarterly basis and ad hoc at the request of the DSMB or the Sponsor (e.g., in the event of unexpected SAEs) to review data throughout the Fixed Duration Treatment Period and the Variable Duration Treatment Period. The DSMB may make recommendations on the conduct of the study, including study termination. Appropriate procedures will be detailed in a DSMB Charter that will define disclosure of any findings along with patient- and study-stopping criteria. There will be four study periods: 1. A six-week screening period (Screening Period); 2. A fixed 24-week double-blind, randomized treatment period (Fixed Duration Treatment Period); 3. A variable-duration, double-blind treatment period (Variable Duration Treatment Period) where patients continue the previously randomized treatment for up to an additional 24 weeks (total blinded duration of 48- weeks). This period will end for all patients when the last-enrolled patient reaches his or her 24-week visit (LP-24Wk) at which time patients in the Variable Duration Treatment Period will complete the EOS Visit at their next scheduled study visit; 4. A four-week follow-up period (Safety Follow-Up Period) for patients not continuing in the separate Open-Label Long-Term Safety Extension Study. Following the end of the blinded treatment period, all patients who complete the 24-week Fixed Duration Treatment Period may be eligible to receive open-label CNM-Au8 in a separate Open-Label Long-Term Safety Extension Study.