Status of Drug Trials for Rett Syndrome Jeffrey

Status of Drug Trials for Rett Syndrome Jeffrey L. Neul M. D. , Ph. D. Division Chief of Child Neurology Department of Neurosciences University of California, San Diego Rady Children’s Hospital – San Diego

Serotonin in Rett syndrome • Important neurotransmitter involved in many clinical features • • Control of breathing Mood Anxiety Decreased in people with RTT and mouse model dopamine serotonin dopamine norepinephrine serotonin

Sarizotan • • 5 HT 1 a agonist/D 2 antagonist Previous evaluated to treat schizophrenia or Parkinson Disease Improved breathing in RTT mice Newron Pharmaceuticals

A RANDOMIZED, DOUBLE-BLIND, PLACEBO-CONTROLLED, SIXMONTH STUDY TO EVALUATE THE EFFICACY, SAFETY AND TOLERABILITY OF SARIZOTAN IN PATIENTS WITH RETT SYNDROME WITH RESPIRATORY SYMPTONS n n n n n Phase 2/3 Double Blind, 2 dose levels + placebo 6 mo drug exposure + 6 mo blind extension Primary Outcome: Improvement in apneas Secondary Outcome: Safety and broad signals of efficacy Inclusion: Clinical Rett syndrome + MECP 2 mutation, + breathing abnormalities Age: Over 13 yo Goal enrollment: 90 (n=30 in each drug level) Sites n n n n University of California, San Diego University of Alabama-Birmingham Baylor College of Medicine Rush University, Chicago Sienna, Italy India Anticipated Start Date (at UCSD): Summer 2016

Mitochondrial abnormalities in Rett syndrome • • Mitochondria are “energy factories” of the cell Evidence of abnormal mitochondria in RTT • • Elevated serum and CSF lactate and pyruvate in some patients Abnormal mitochondria morphology Abnormal expression of proteins involved in mitochondrial function Hypothesis: Improving mitochondrial function will improve clinical features in RTT

Mitochondrial abnormalities in Rett syndrome: Triheptahoin • • C 7 fatty acid metabolized to C 4 and C 5 ketone bodies Provides alternative energy source to brain Improves mitochondrial function Improved seizures in Glut 1 deficiency • • • Improved metabolic profile Better motor performance Improved survival Preclinical treatment in RTT mouse model Park et al, PLOSOne, 2014

Triheptahoin clinical trial Emory University, Daniel Tarquinio n n Phase 2 a, open label study of 10 subjects Clinical RTT and mutation in MECP 2 n n n Primary outcome: Safety and Tolerability Secondary outcomes: n n n Improvement in seizure frequency Improvement in dystonia severity Exploratory outcomes: n n >4 seizures per month, >4 dystonic episodes per month Quality of life Improved function EEG and Ambulatory biometric devices (autonomic function, movement, oxygen saturation, electrodermal activity) Not yet enrolling

Disease modifying therapies Male Mecp 2 mice treated with tripeptide from N-terminus of IGF-I [1 -3] = Gly-Pro-Glu

IGF-I trials in Rett syndrome n Full-length IGF-I (mecasermin) in children with Rett syndrome n n Boston Children’s Hospital Trofinetide (NNZ-2566) in adults with Rett syndrome Baylor College of Medicine, Houston TX n University of Alabama-Birmingham n Gillette Children’s Hospital, St. Paul MN n

IGF-I trials in Rett syndrome n Full-length IGF-I (mecasermin) in children with Rett syndrome n n Boston Children’s Hospital Trofinetide (NNZ-2566) in adults with Rett syndrome Baylor College of Medicine, Houston TX n University of Alabama-Birmingham n Gillette Children’s Hospital, St. Paul MN n

Children’s Hospital Boston rh. IGF-1 clinical trial (NCT 01253317) n n n Treatment with full length IGF 1 (Mecasermin), initiated December 2010 n Phase I: open-label escalating subcutaneous twice daily doses (40, 80, and 120 ug/kg) for 4 weeks to assess safety Primary outcome: Safety Secondary: improvement in cardiovascular function as measured by respiratory inductance plethysmography and electrocardiogram Exploratory evaluation: Function, behavior, biomarkers Results: safe and some signals of efficacy

Children’s Hospital Boston rh. IGF-1 clinical trial (NCT 01253317) n PHASE 2: Double blind, placebo controlled, cross over, single dose study n n 30 people Randomized to drug or placebo n n n 20 weeks exposure 10 week wash out 20 week exposure Primary outcomes-breathing, anxiety Completed enrollment Analyzing data to determine next steps

IGF-I trials in Rett syndrome n Full-length IGF-I (mecasermin) in children with Rett syndrome n n Boston Children’s Hospital Trofinetide (NNZ-2566) in adults with Rett syndrome Baylor College of Medicine, Houston TX n University of Alabama-Birmingham n Gillette Children’s Hospital, St. Paul MN n

Phase 2 Study of Two Dose Levels of NNZ-2566 ([1 -3] IGF-1 analog) Cohort 0 2: 1 Randomization 35 mg/kg BID or Placebo 14 Days Treatment N=9 Cohort 1 2. 1 Randomization 35 mg/kg BID or Placebo 28 days treatment N=18 Cohort 2 2: 1 Randomization n n 70 mg/kg BID or Placebo 28 days of treatment N=29 N=56, Ages 15. 9 -44. 2 (mean 25. 3) Primary Outcome: Safety/Tolerability Secondary Outcome: Efficacy Funded by Neuren Pharmaceuticals (Sponsor) and the International Rett Syndrome Foundation 14

70 mg/kg BID Dose of NNZ-2566 Demonstrates Evidence of Efficacy Subject-Level Score Top 3 Concerns MBA Change Index n Achieved its primary endpoint - both dose levels of NNZ-2566 were welltolerated after 28 days of treatment and no safety concerns were identified. Higher dose exceeded the pre-specified criteria for improvement in core efficacy measures compared with placebo on group and subject level analysis CGI-I n Least Squares mean change from baseline to Day 26 (Direction of benefit = Up) *modified intent to treat group, n=55

Next steps: A Safety Study of NNZ-2566 in Pediatric Rett Syndrome n Double-blind, placebo controlled doseranging study n n n n n 3 dose levels Similar in design to first trial (RTT-001) Younger age range (5 -15 yo) Clinical RTT and MECP 2 mutation Cannot have QTc prolongation 11 weeks total time (56 days on compound) Primary outcome: Safety Secondary outcome: Signals of efficacy Goal enrollment: >64

Next steps: A Safety Study of NNZ-2566 in Pediatric Rett Syndrome n Enrolling n n n n Setting up n n n University of Alabama-Birmingham Greenwood Genetics Center, SC Baylor College of Medicine Vanderbilt University Rush University Boston Children’s Hospital University of California, San Francisco University of California, San Diego (summer 2016) Gillette Children’s Hospital, St. Paul, MN Colorado Children’s Hospital Cincinnati Children’s Hospital www. rettstudy. com

Ketamine Treatment for RTT • • Ketamine is a NMDA antagonist used for sedation (amnestic) Evidence for efficacy at low doses for major depression Evidence of increased cortical neuronal excitability in RTT Preclinical treatment in mice • • • Delayed onset of breathing problems Improved sensory gating Improved survival Kron et al. , 2012; Mather et al. , 2014, Patrizi et al, 2014

Ketamine Treatment for RTT • • • David Katz, Case Western Reserve University and Sumit Parikh, Cleveland Clinic Phase I/II placebo-controlled randomized crossover Goal enrollment: 30 Inclusion • • Clinical RTT and MECP 2 mutation Evidence of breathing abnormality • • Breathing Auditory evoked potentials Functional improvement on rating scales Primary outcome: Safety Exploratory • • Not yet started

Lovastatin-NYC n Montefiore (NYC), Aleksandra Djukic n n Phase II, Open Label, Dose-escalating study in RTT with MECP 2 mutations and can walk Goal enrollment: N=20, >3 yo 32 week treatment, with dose escalation Outcome measures Primary: Gait n Secondary n n n Breathing Visual recognition using eye tracking device EEG abnormalities Quality of Life Recruiting subjects

Acknowledgements n n n Daniel Tarquinio, Emory University, Atlanta GA Aleksandra Djukic, Children’s Hospital at Montefiore, Albert Einstein Medical School, New York, NY Bruria Ben-Zeev, Sheba Medical Center, Israel David Katz, Case Western University, Cleveland, OH Walter Katz Rett Syndrome Natural History Study – Alan Percy n n n NIH Rettsyndrome. org Rett Syndrome Research Trust

Thank you

Copaxone trials n n Copaxone: An artificial copolymer of peptide pool composed of random sequence of 4 amino acids : glutamine, lysine, alanine and serine Used for >20 yrs for Multiple Sclerosis n n Elevated serum BDNF levels were detected in MS patients only during copaxone Increases BDNF in brain of RTT mice Control Copaxone Ben-Zeev et al, 2011

Copaxone trials-NYC n Montefiore (NYC), Aleksandra Djukic n Phase II, Open Label, Dose-escalating study in RTT with MECP 2 mutations n Need to be able to walk Goal enrollment: N=20, >10 yo n 24 week treatment, with dose escalation n Outcome measures n n Primary: Gait n Secondary n n n Breathing Visual recognition using eye tracking device EEG abnormalities

Copaxone trials-NYC n Montefiore (NYC) Stopped after 10 people completed trial n Results: n n Gait: 7/10 improved gait speed (13. 1%-95. 2%) n Breathing: 5/10 showed improved breathing holding index n Visual recognition: 5/7 showed improvement in cognitive assessment of face stimuli n EEG: Epileptiform discharges decreases in 4/4 who had them at baseline

Copaxone trials-Israel n Sheba Medical Center (Israel), Bruria Ben Zeev n n Phase II, Open Label, Dose-escalating study in RTT with MECP 2 mutations and EEG abnormalities Goal enrollment: N=10, 5 -15 yo 24 week treatment, with dose escalation Outcome measures n Primary n n n Safety Improvement in EEG abnormalities Secondary n n n Improved breathing Decreased seizures Improved sleep Improved behavior Changes in Height and Weight

Copaxone trials-Israel n 10 people recruited n n n One had increase in seizure frequency and decided to stop the trial 4/10 mild irritation at injection site After 3 mos one subject had flushing, mild generalized edema tremor and breath holding immediately after injection n n 2 wks later 2 more subjects reported similar (immediate) but more prolonged and prominent response after injection n Subsequent injections ok, continued on study one subsided spontaneously after few hours of observation in ER One had significant generalized edema , breathing difficulties followed by seizure and requiring adrenaline injection by paramedic and hospitalization, remission after 24 hours Report to IRB – Decision to hold study and investigate SAE

Copaxone trials-Israel n IRB Review n n Evaluation of events and input on safety from Montefiore Decision to reopen study 4 more subjects recruited 3 months into the study n similar severe response in one subject Edema, flushing, prolonged breath holding and possibly seizure immediately after injection –severe enough to call paramedic team and transfer to close ER – Spontaneous remission in 1 -2 hours n Response frightening enough to very experienced parents n n IRB review of SAE – decided to stop study

Copaxone trials-Conclusion n Montifiore Safe n Positive signals of efficacy n n Israel n n Multiple SAE Future - uncertain