Actualité dans le traitement pharmacologique de l’Ataxie Télangiectasie

1. Università degli Studi di Brescia – Facoltà di Medicina e Chirurgia U.O. di Neuropsichiatria Infantile - Spedali Civili - Brescia Actualité dans le traitement pharmacologique de l’Ataxie Télangiectasie Current therapeutic strategies for the treatment of Ataxia-Telangiectasia Roberto Micheli, MD

2. ATAXIA-TELANGIECTASIA • Definition: rare autosomal recessive multisystemic disorder. • Incidence:1: 300.000 – 1: 40.000 in newborns. • Etiology: biallelic mutations in the ATM gene (Chr 11q22-23), that encodes a • protein kinase which plays a pivotal role in DNA repair, targeting hundreds of substrates involved in cell cycle checkpoints. • Pathogenesis:DNA-repair defect syndromes. • In neuronal cells, unrepaired DNA tend to accumulate and eventually cause the death of Purkinje cells. • Oxidative processes, induced by release of oxygen radicals from the mitochondria, is a major contributor to neurodegeneration. • Patients with ataxia telangiectasia are especially prone to oxidative stress, because the ATM protein by itself is a scavenger of reactive oxygen species.

3. ATAXIA-TELANGIECTASIA : CLINICAL MANIFESTATIONS

4. ATAXIA TELANGIECTASIA: DIAGNOSIS • High serum alpha-fetoproteinlevel (95% pt.). • Chromosomal instability (chromosome breakage, inversions and translocations > chromosomes 7 and 14). • Increase in spontaneous and radiation-induced chromosomal breaks. • Reduced/absent IgA levels (70%) and ATM protein (98%) • Proven molecular diagnosis of A-T based on ATM gene mutations and/or ATM protein deficiency (Western Blot).

5. ATAXIA-TELANGIECTASIA: PROGNOSIS • Progressive neurodegeneration. • Dramatically affect the quality of life: wheelchair dependency toward the second decade of life. • Prognosis is poor: life expectancy is around 25 years, with a wide range. Pulmonary infections and cancer are the two most common causes of death in patients with A-T.

6. ATAXIA-TELANGIECTASIA : NEUROLOGICAL DYSFUNCTION • Cerebellarataxia (100% pt.) • Generally the presentingsymptom; progressive. • Narrowgaitataxia. • Neckposturing (anterior or posterior bending). • Extrapyramidalinvolvement (70% pt.) • Disabling, in some cases prevalent manifestations. • Hyperkineticmovementdisorders / Parkinsonianfeatures. • Eyemovementabnormalities (80% pt.) • Oculomotorapraxia. • Significantmorbidity, including readingimpairment. SM axonal peripheral neuropathy Cognitive profile

7. ATAXIA-TELANGIECTASIA: TREATMENT • No established therapy is currently available • Treatments are symptomatic and supportive only • Therapy and prophylaxis of infections: • Early antibiotic treatment and continuous prophylactic therapy ; • Vaccines (S. pneumoniae;N. meningitidis; H. Influenzae); • Regular injection of immunoglobulins. • Rehabilitation and supportive care: • Physical, occupational and speech/swallowing neurorehabilitation. • Adaptive equipment, including braces, walkers, orthotics, wheelchairs and computers • X-ray exposure should be limited to times when it is medically necessary!

8. POTENTIAL THERAPEUTIC STRATEGIES • Use of antioxidants • Mutation-targeted therapies: • Correction of ATM gene function by read-through of premature termination codons (aminoglycosides) • Correction of ATM splicing mutations with antisense morpholino oligonucleotides

9. POTENTIAL THERAPEUTIC STRATEGIES Oral Betamethasone

10. POTENTIAL THERAPEUTIC STRATEGIES Oral Betamethasone

11. A Randomized Trial of Oral Betamethasone to Reduce Ataxia Symptoms in Ataxia Telangiectasia Zannolliet al., 2012

12. A Randomized Trial of Oral Betamethasone to Reduce Ataxia Symptoms in Ataxia Telangiectasia Zannolliet al., 2012 Study design summarizing the double-blind crossover trial of BETA versus placebo

13. A Randomized Trial of Oral Betamethasone to Reduce Ataxia Symptoms in Ataxia Telangiectasia Zannolliet al., 2012 Association between the change in ICARS total score and plasma level of BETA in the ITT population. • Higher BETA plasma levels corresponded with greater decreases in ICARS total score and corresponding improvement in ataxia symptoms. • All 13 but 2 patients (patients 8 and 13) had improved ataxia symptoms during the BETA treatment.

14. A Randomized Trial of Oral Betamethasone to Reduce Ataxia Symptoms in Ataxia Telangiectasia Zannolliet al., 2012 Data are medians (ranges). Thirteen ITT A-T patients are included. In this trial, BETA reduced ICARS total score by a median of 13 points in the ITT population and 16 points in the PP population (median percent decreases of ataxia symptoms of 28% and 31%, respectively).

15. A Randomized Trial of Oral Betamethasone to Reduce Ataxia Symptoms in Ataxia Telangiectasia Zannolliet al., 2012

17. POTENTIAL THERAPEUTIC STRATEGIES Dexamethasone Sodium Phosphate Encapsulation in Human Erytrhtocites To avoid theside effects of long-term administration of steroidswe utilized a method for encapsulation of dexamethasone sodium phosphate (DSP) into autologous erythrocytes (EryDex method) allowing slow release of dexamethasone for up to one month after dosing

18. POTENTIAL THERAPEUTIC STRATEGIES Dexamethasone Sodium Phosphate Encapsulation in Human Erytrhtocites

19. EryDex System LOAD Dexamethasone INTO RED BLOOD CELLS BY MEANS OF DEDICATED CE MARKED SYSTEM 2 WITHDRAWAL OF 50 ml OF WHOLE BLOOD FROM THE PATIENT 1 3 AUTOLOGOUS LOADED RBC REINFUSION TO THE PATIENT

20. Intra-Erythrocyte Infusion of Dexamethasone Reduces Neurological Symptoms in Ataxia Teleangiectasia Patients: Results of a Phase 2 Trial

21. Evaluation of Effects of Intra-Erythrocyte Dexamethasone SodiumPhosphate on Neurological Symptoms in Ataxia-Telangiectasia Patients STUDY OBJECTIVES: A single-arm, open-label, 6-month Phase II clinical trial, conducted in 22 AT patients (mean age 11.2 years) in two Italian centres (Brescia and Roma)

22. Evaluation of Effects of Intra-Erythrocyte Dexamethasone SodiumPhosphate on Neurological Symptoms in Ataxia-Telangiectasia Patients INCLUSION CRITERIA: • Neurological signs of AT • Patients in autonomous gait or helped by a support • Proven molecular diagnosis of AT • Males and females aged >3 years • Body weight >15 Kg • Plasma levels of CD4+ lymphocytes/mm3 ≥500 (for patients aged 3-6 years) or ≥200 (for patients older than 6 years) • Written IC to participate from the patient or from the parents (or from a legal acceptable representative)

23. Evaluation of Effects of Intra-Erythrocyte Dexamethasone SodiumPhosphate on Neurological Symptoms in Ataxia-Telangiectasia Patients EXCLUSION CRITERIA: • Current or previous neoplastic disease • History of severe impairment of the immunological system • Chronic conditions representing a contraindication to the use of steroid drugs • Noncompliance with the study protocol • Have participated in any other investigational trial within 30 days from Screening Period • Any previous steroid use within 30 days before starting ERY-DEX • Have any other significant disease that in the Investigator’s opinion would exclude the patient from the trial • Females of childbearing potential who were pregnant, breast-feeding or were not using adequate contraceptive methods

24. screened n = 26 enrolled n = 22 screening failure n = 4 completed study n = 18 premature terminations n = 4 CD4+ lymphocytes below the limit n = 3 concomitant disease n = 1 CD4+ lymphocytes below the limit n = 1 (protocol violation) consent withdrawal n = 1 dropouts due to AEs n = 2 Evaluation of Effects of Intra-Erythrocyte Dexamethasone SodiumPhosphate on Neurological Symptoms in Ataxia-Telangiectasia Patients STUDY DISPOSITION:

25. Evaluation of Effects of Intra-Erythrocyte Dexamethasone SodiumPhosphate on Neurological Symptoms in Ataxia-Telangiectasia Patients ASSESSMENTS • International Cooperative Ataxia Rating Scale (ICARS) • Vineland Adaptive Behavior Scales (VABS) • Investigator’s Global Assessment (IGA) • Ocular motility (measured by an ‘ad hoc’ form) • Physical examination, vital signs, ECG and laboratory tests

26. screening Visit (days 30→0) Infusion Infusion Infusion Infusion Infusion Infusion V1 V2 V3 V 4 V5 V6 V7 ICARS ICARS ICARS ICARS six months study (6 treatments) 3 weeks Evaluation of Effects of Intra-Erythrocyte Dexamethasone SodiumPhosphate on Neurological Symptoms in Ataxia-Telangiectasia Patients STUDY DESIGN: 22 enrolled (ITT) 4 drop-outs 18 completed (PP) 26 screened

27. Evaluation of Effects of Intra-Erythrocyte Dexamethasone SodiumPhosphate on Neurological Symptoms in Ataxia-Telangiectasia Patients TOTAL SCORE : ICARS Mean ICARS Total Score and Changes from Baseline (V1) by Visit (ITT Population) *Comparison vs. baseline (V1) using Wilcoxon non-parametric test.

28. Evaluation of Effects of Intra-Erythrocyte Dexamethasone SodiumPhosphate on Neurological Symptoms in Ataxia-Telangiectasia Patients PRIMARY END-POINT: ICARS I 1. WALKING CAPACITIES I 2. GAIT SPEED I 3. STANDING CAPACITIES, EYES OPEN I 4. SPREAD OF FEET IN NATURAL POSITION WITHOUT SUPPORT, EYES OPEN I 5. BODY SWAY WITH FEET TOGETHER EYES OPEN I 6. BODY SWAY WITH FEET TOGETHER EYES CLOSED I 7. QUALITY OF SITTING POSITION POSTURE AND GAIT DISTURBANCE ICARS TOTAL SCORE II 08. KNEE-TIBIA TEST: decomposition of movement II 09. ACTION TREMOR in the HEEL-TO-KNEE Test II 10. FINGER-TO-NOSE TEST: decomposition and dysmetria II 11. FINGER-TO-NOSE TEST: intention tremor II 12. FINGER-FINGER TEST: action tremor and instability II 13. PRONATION SUPINATION altering ovements II 14. DRAWING the Archimedes spiral KINETIC FUNCTIONS SPEECH DISORDERS III 15. DYSARTHRIA: fluencyofspeech III 16. DYSARTHRIA: clarityofspeech IV 17. GAZE EVOKED NYSTAGMUS IV 18. ABNORMALITIES OF THE OCULAR PURSUIT IV 19. DYSMETRIA OF THE SACCADE OCULOMOTOR DISORDERS

29. Evaluation of Effects of Intra-Erythrocyte Dexamethasone SodiumPhosphate on Neurological Symptoms in Ataxia-Telangiectasia Patients SECONDARY END-POINTS VABS Statistically significantimprovements were noted in adaptive behavior (total score, p<0.0001), with significant increases at 3 and 6 months (p<0.0001). Ocular Motility Statistically significant improvementswere noted at 3 and 6 months (p=0.021 and p=0.002). IGA Statistically significant improvements in global health status were noted at 3 and 6 months (p=0.003 and p=0.005, respectively). • Safety • Most Frequent AE: Cough (6), Fever (4), Otitis (3), Bronchitis (2); • Most events represent recurrencies of medical illness patients had experienced prior to the study; • None of these adverse events was considered related to the study medication

30. Evaluation of Effects of Intra-Erythrocyte Dexamethasone SodiumPhosphate on Neurological Symptoms in Ataxia-Telangiectasia Patients DATA ANALYSIS REVEALED: • a wide interindividual variability in the variations of ICARS scores • (range -16 +9) • a substantial variability in the patient-specific DSP-erythrocyte loading (the mean dose ranged from 0.7 to 18.6 mg per bag) • a greater proportion of loaders (mean doses of DSP of 5 mg or more) among females rather than males (80% vs 27%) • the efficiency of the erythrocytes loading was related to greater improvement  responders females > males (73% vs 18%) • patients with milder basal ICARS score (42 +- 1) experienced a better improvement (mean 11.3 points)

31. Evaluation of Effects of Intra-Erythrocyte Dexamethasone SodiumPhosphate on Neurological Symptoms in Ataxia-Telangiectasia Patients Exploratory analysis for dose response

32. Chronic treatment with ERY-DEX Long term benefit confirmed with compassionate treatment up to 18 months

33. Evaluation of Effects of Intra-Erythrocyte Dexamethasone SodiumPhosphate on Neurological Symptoms in Ataxia-Telangiectasia Patients

34. STEROIDS in AT • Cerebellar ataxia improved • Oculomotor apraxia improved • Extrapyramidal involvement not improved • Peripheral neuropathy  not improved

35. TREATMENT OF EXTRAPYRAMIDAL SYMPTOMS Drugs that increase dopamine in the striatum treat parkinsonism but exacerbate hyperkinetic movements, and vice versa

36. POTENTIAL THERAPEUTIC STRATEGIES Amantadine Sulfate

37. POTENTIAL THERAPEUTIC STRATEGIES Amantadine Sulfate • Open label, prospective study • 17 children (F:M=5:12; mean age 11.2 years) • 8 weeks, 3 visits, amantadine dosage gradually titrated up to 7 mg/kg/day • Neurological assessement: International Cooperative Ataxia Scale (ICARS); Unified Parkinson Disease Rating Scale (UPDRS); • Abnormal Involuntary Movement Scale (AIMS); • Severity of the neurological involvement: ad hoc AT score (sum of the 3 scales)

38. POTENTIAL THERAPEUTIC STRATEGIES Amantadine Sulfate

39. POTENTIAL THERAPEUTIC STRATEGIES Amantadine Sulfate • 76.5% responders(mean improvement 29.3%) • Increasing the dosage5 to 7 mg/kg/day increased response • Well tolerated(mild and transient side effects) • Compassionate treatment(9 patients, 1 year) no significant change in neurological score as compared with 8 weeks’ visit. • No compassionate treatment(7 patients, 1 year)  significant neurological deterioration • Improvement of both parkinsonism and hyperkinetic movements

40. screening Visit (days 30→0) V1 V2 V3 Up to 4 mg/kg Up to 8 mg/kg ICARS ICARS ICARS Twomonthsstudy (Tapering1 MG/KG/WEEK) POTENTIAL THERAPEUTIC STRATEGIES L- Dopa AIMS AIMS AIMS UPDRS UPDRS UPDRS 10 screened 7 enrolled

41. POTENTIAL THERAPEUTIC STRATEGIES L-Dopa/Amantadine

42. CONCLUSIONS • Efficacy of steroids in improving ataxia of AT patients has been proven in the last 5 years • To avoid the side effects of long-term administration of steroids, EryDex method may be a promising challenge • Extrapyramidal symptoms may be ameliorated by dopaminergic or NMDA antagonists, but long-term, placebo-controlled studies are needed • In the future we are looking for a long-term treatmentcombining both steroids and dopaminergic/NMDA antagonists, to improve both ataxia/oculomotor apraxia and parkinsonism/movement disorders. • Early treatment in asymptomatic children could be speculated to delay neurological degeneration

45. ITT population Number of patient (divided for Trial Center: 1–Roma and 2-Brescia), sex, date of birth, molecular identification, number of infusions and mean dose of DSP loaded

46. Demographic and clinicalcharacteristics at baseline

47. Primaryefficacyend-pointmet Mean ICARS Total Score over the 6-Month Study Period (ITT Population) *(p= 0.02) RMANOVA analysis

48. Secondaryend-point: VABS *p< 0.0001 RMANOVA analysis Mean VABS Total Score over the 6-Month Study Period (ITT Population)

49. Secondaryend-point: OcularMotility (*p= 0.014) RMANOVA analysis Mean Ocular Motility Assessment Score by Visit (ITT Population)