NSI-189, a neurogenic compound, in Phase 1b trial demonstrates clinical and QEEG effects in major depressive disorder patients Ereshefsky L1, English, BA. 1,2, Johnstone J3, Johe K4, Gertsik L5, Sherman S1, Fava M6, Freeman M6 1 2. 3. 4. 5. 6. PAREXEL International, Los Angeles Early Phase Unit Vanderbilt University QMetrx Inc. Neuralstem Inc. California Clinical Trials Medical Group Massachusetts General Hospital, Harvard Medical School Methodological Question Being Addressed: Phase 1B trials typically evaluate safety and efficacy in healthy controls and have limited pharmacodynamic assessments. The use of patients rather than healthy volunteers in early development speeds drug development, incorporates inclusion of relevant biomarkers and behavioral endpoints. Adjudication of patients for diagnosis and severity of illness are important measures to insure maximal signal detection in small early development studies. QEEG may provide greater sensitivity in small trials to detect differences from placebo, and might serve as a surrogate for efficacy. Decisions to proceed to larger POC studies can be better informed using small patient trials. INTRODUCTION: NSI-189, a possible treatment of MDD, stimulates neurogenesis in human hippocampus-derived neural stem cells in vitro,in mouse hippocampus in vivo, and shows behavioral efficacy in novelty suppressed feeding paradigm with daily 28-day oral administration. In previous trials with SSRI’s high frequency alpha in the left posterior temporal region has correlated with changes in mood rating scales. Evaluation of clinical endpoints and QEEG measurements in Phase 1b studies can provide information supporting progression to POC. METHODS: In previous reports of a Phase 1 single-dose study, NSI-189 was shown to be rapidly absorbed and well tolerated. This double-blind, RPCT with 3 ascending cohorts, patients (n=24) enrolled confirmed major depressive disorder (MDD) using remote SAFER interview. Patients were randomized to receive NSI-189 40 mg QD, BID or TID or placebo (PBO) for 28 days. Safety EEGs surrounding Tmax and QEEG measurements for antidepressant response were obtained 6hrs post-dose on Day 14 and 28. Efficacy assessments included the Montgomery-Asberg Depression Rating Scale (MADRS), the Clinician Global Impression – Improvement (CGI-I), the Symptoms of Depression Questionnaire (SDQ) and the Cognitive and Physical Functioning Questionnaire (CPFQ). RESULTS: A clinically meaningful reduction in depressive and cognitive symptoms across the MADRS (Day 28 d=0.95; Day 84=0.84), SDQ (Day 28 d=0.9; Day 84=1.10), and CPFQ (Day 28 d=0.94; Day 84=1.20) assessment scales was observed for patients on NSI-189 compared with placebo. Safety EEGs consisted of the visual inspection of all of the 20 minute clinical EEG recordings pre vs. post dose. Most subjects showed no abnormal findings at Screening. Several cases showed minor findings that were not considered epileptiform in character. No new EEG findings were identified by visual inspection post-dose that were persistent in final recordings. No seizure activity was observed in any case. The quantitative EEG analyses showed increased high frequency alpha with NSI-189 treatment (change from baseline to Day 14 and to Day 28) in contrast to decreased high frequency alpha or less change with placebo. The NSI-189 effect is most prominent in the left posterior temporal (T5) (t=2.45, p=0.0247) and left parietal regions (P3) (t=3.31, p=0.004) and is similar when comparing QEEG at baseline to either Day 14 or Day 28 assessments. CONCLUSIONS: NSI-189, a novel compound with preclinical antidepressant properties was safely tolerated as monotherapy in patients with MDD. These findings demonstrate a measurable impact on NSI-189 on brain electrical activity in a population of patients with major depressive disorder. The largest effect was seen for the active treatment group in the higher frequency alpha range in the left posterior temporal region. This type of finding is consistent with improvement in left temporal lobe function but may also reflect changes in activity in left mesial temporal lobe and hippocampus. Methodologically, small Phase Ib patient studies can yield relevant data to contribute to go no-go decisions. These preliminary findings support the further development of NSI-189 as a potential neurogenesis activator for the treatment of depression. Limitations of this study include the small sample size, and the sequential escalating dose structure of a Phase 1 trial. Disclosures: All authors’ institutions received funding from Neuralstem Inc. Each of the author’s institutions engages in clinical trials work supported by numerous Pharmaceutical and biotechnology companies.