8-K

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM 8-K

CURRENT REPORT

Pursuant to Section 13 or 15(d) of the
Securities Exchange Act of 1934

Date of Report (Date of earliest event reported): April 25, 2017

AVEXIS, INC.

(Exact name of registrant as specified in its charter)

Delaware

(State or other jurisdiction of incorporation)

001-37693	90-1038273
(Commission File No.)	(IRS Employer Identification No.)

2275 Half Day Rd, Suite 200

Bannockburn, Illinois 60015

(Address of principal executive offices and zip code)

Registrant’s telephone number, including area code: (847) 572-8280

(Former name or former address, if changed since last report.)

Check the appropriate box below if the Form 8-K filing is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions:

o Written communications pursuant to Rule 425 under the Securities Act (17 CFR 230.425)

o Soliciting material pursuant to Rule 14a-12 under the Exchange Act (17 CFR 240.14a-12)

o Pre-commencement communications pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240.14d-2(b))

o Pre-commencement communications pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR 240.13e-4(c))

Indicate by check mark whether the registrant is an emerging growth company as defined in Rule 405 of the Securities Act of 1933 (§230.405 of this chapter) or Rule 12b-2 of the Securities Exchange Act of 1934 (§240.12b-2 of this chapter).

Emerging growth company   x

If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 13(a) of the Exchange Act.   x

Item 7.01              Regulation FD Disclosure.

On April 25, 2017, AveXis, Inc. (the “Company”) will host a live webcast to report on results from the closeout of the Company’s Phase 1 clinical trial of AVXS-101 for the treatment of spinal muscular atrophy (“SMA”) Type 1.  These data were presented by Jerry Mendell, M.D., principal investigator in the trial and Curran-Peters Chair of Pediatric Research, Professor of Pediatrics and Neurology at the Research Institute at Nationwide Children’s Hospital and The Ohio State University, during the Clinical Trial Plenary Session at the 2017 Annual Meeting of the American Academy of Neurology in Boston, Massachusetts.  A copy of the slides to be presented during the webcast is being furnished as Exhibit 99.1 to this Current Report on Form 8-K.

The information in this Item 7.01 of this Current Report on Form 8-K (including Exhibit 99.1) is being furnished and shall not be deemed “filed” for purposes of Section 18 of the Securities Exchange Act of 1934, as amended (the “Exchange Act”), or otherwise subject to the liabilities of that Section, nor shall it be deemed incorporated by reference in any filing under the Securities Act of 1933, as amended, or the Exchange Act, except as expressly set forth by specific reference in such a filing.

Item 8.01              Other Events.

On April 25, 2017, the Company issued a press release reporting on the results from the closeout of the Company’s Phase 1 clinical trial of AVXS-101 for the treatment of SMA Type 1 as presented by Dr. Mendell at the 2017 Annual Meeting of the American Academy of Neurology.  The full text of the Company’s press release regarding the announcement is filed as Exhibit 99.2 to this Current Report on Form 8-K and is incorporated herein by reference.

Item 9.01              Financial Statements and Exhibits.

(d) Exhibits

Exhibit
Number	Exhibit Description
99.1	Slide Presentation, dated April 25, 2017, titled “AVXS-101 Clinical Update As Presented at the American Academy of Neurology 2017 Annual Meeting.”
99.2	Press Release, dated April 25, 2017, titled “AveXis Presents Results from Phase 1 Clinical Trial of AVXS-101 in SMA Type 1 at the Annual Meeting of the American Academy of Neurology.”

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SIGNATURES

Pursuant to the requirements of the Securities Exchange Act of 1934, the Registrant has duly caused this report to be signed on its behalf by the undersigned hereunto duly authorized.

Date: April 25, 2017	AVEXIS, INC.
	By:	/s/ Sean P. Nolan
		Sean P. Nolan
		President and Chief Executive Officer

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EXHIBIT INDEX

Exhibit
Number	Exhibit Description
99.1	Slide Presentation, dated April 25, 2017, titled “AVXS-101 Clinical Update As Presented at the American Academy of Neurology 2017 Annual Meeting.”
99.2	Press Release, dated April 25, 2017, titled “AveXis Presents Results from Phase 1 Clinical Trial of AVXS-101 in SMA Type 1 at the Annual Meeting of the American Academy of Neurology.”

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EX-99.1

Exhibit 99.1

April 25, 2017 AVXS-101 Clinical Update As Presented at the American Academy of Neurology 2017 Annual Meeting

2 Forward-Looking Statements This presentation contains forward-looking statements, including statements about: the timing, progress and results of preclinical studies and clinical trials for AVXS-101, including statements regarding the timing of initiation of studies or trials and related preparatory work, our expectations regarding timing for meetings with regulatory agencies, our manufacturing strategy and developments, key regulatory and development milestones and our research and development programs. These statements involve substantial known and unknown risks, uncertainties and other factors that may cause our actual results, levels of activity, performance or achievements to be materially different from the information expressed or implied by these forward-looking statements. We may not actually achieve the plans, intentions or expectations disclosed in our forward-looking statements, and you should not place undue reliance on our forward-looking statements. Actual results or events could differ materially from the plans, intentions and expectations disclosed in the forward-looking statements we make. The forward-looking statements in this presentation represent our views as of the date of this presentation. We anticipate that subsequent events and developments will cause our views to change. However, while we may elect to update these forward-looking statements at some point in the future, we have no current intention of doing so except to the extent required by applicable law. You should, therefore, not rely on these forward-looking statements as representing our views as of any date subsequent to the date of this presentation. Disclaimers

Our Strategy 3 Build pipeline of gene therapy treatments beyond SMA Expand development of AVXS-101 into SMA Type 2 Establish foundational presence in SMA Type 1 Vision: Leader in rare and life-threatening neurological genetic diseases Strategic Focus & Investment Time

Overview of SMA 4 SMA is a devastating orphan disease that results in motor neuron loss and progressive weakness; it is the most common genetic cause of infant death Incidence: ~1 in 10,000 live births Caused by reduced SMN (survival motor neuron) protein levels from loss of/defective SMN1 gene SMA divided into sub-categories, Type 1- 4, with Type 1 being most severe Severity correlates with # of copies of SMN2 backup gene

SMA Types: A Devastating Disease 5 TYPE 1 TYPE 2 TYPE 3 TYPE 4 SMN2 Copy Number Two Three or Four Three or Four Four to Eight Onset Before 6 Months 6-18 Months Early childhood to early adulthood (juvenile) Adulthood (20s-30s) usually after 30 Incidence per Live Birth Approximately 60% Approximately 27% Approximately 13% Uncommon; limited information available Developmental Milestones Will never be able to sit without support Difficulty breathing & swallowing Can’t crawl/will never walk Will never be able to walk or stand without support Stand alone and walk but may lose ability to walk in 30s-40s Stand alone and walk but may lose ability to walk in 30s-40s (Same as Type 3) Survival <10% Event free* by two years of age 68% alive at age 25 Normal Normal *Event = Death or ≥16-hr/day ventilation continuously for ≥ 2 wks, in the absence of an acute reversible illness

Natural History of SMA Type 1 “floppy baby” syndrome muscle weakness (legs more than arms) poor head control belly breathing bulbar muscle weakness (weak cry, difficulty swallowing, aspiration) will never sit unsupported loss of motor function: NeuroNEXT -- CHOP INTEND decrease of 10.5 points/yr. PNCR -- CHOP INTEND decrease of 1.27 points/yr. % Event-Free Survival* Age (mos.) PNCR (Finkel) NeuroNEXT (Kolb) *Survival for Finkel1 = no death, or no need for ≥16-hr/day ventilation continuously for ≥ 2 weeks, in the absence of an acute reversible illness; n = 23 (2 copies of SMN2) Survival for Kolb2 = no death, or no tracheostomy; n = 20 75% survival 8.1 mos 50% survival 10.5 mos 25% survival 13.6 mos 8% survival 20 mos Holds head steady alone; brings hands to mouth Rolls over in both directions Sits alone; crawls Cruises; may stand alone Walks alone; may run and walk up stairs; eats with a spoon Climbs furniture alone; kicks and throws a ball Onset of SMA Type 1 by 6 months Symptoms may present More than 90% of SMA Type 1 patients will not survive or will need permanent ventilation support by age 2 6 Milestone for a healthy infant SMA Type 1 survival rates per Finkel1 50% survival 8 mos SMA Type 1 survival rate per Kolb2 0 25 50 75 100 0 2 4 6 8 10 12 14 16 18 20 22 24

Children with SMA Type 1 Do Not Reach Any Major Motor Milestones Retrospective Study from large multi-center datasets (US and EU) Patients (n=33) have genetically confirmed homozygous deletion of exon 7 in SMN1 gene; categorized according to Dubowitz’s decimal classification (confirmation of SMN1 status and clinical observations) Study visits at baseline, every 2-3 months until the age of 12 months, and every 6 months thereafter, when possible Hammersmith Infant Neurological Examination (HINE) used to assess intermediate steps leading to full achievement of milestones DESIGN Prolongation of survival with supportive care does not impact achievement of motor milestones in SMA Type 1 infants SMA Type 1 infants with symptom onset <6 months: Will not reach any major motor milestones, such as sitting, crawling, standing, and walking Any early intermediate milestones in 1B patients will be quickly lost The highest milestone achieved is seen in the child’s first visit followed by a rapid decline Any improvement or achievement of milestones not usually achieved in a child with SMA Type 1 in a drug intervention trial can be attributed to the drug and not due to survival or enhanced standard of care CONCLUSIONS Developmental Milestones in Type 1 Spinal Muscular Atrophy De Sanctis et al. Neuromuscular Disorders, Nov-2016 7

AVXS-101 Targets the Primary SMN Gene 8 NORMAL INDIVIDUAL SMA-AFFLICTED INDIVIDUAL SMA-AFFLICTED INDIVIDUAL TREATED WITH AVXS-101 SMN Genes SMN Protein SMN1 Primary SMN2 Back up SMN Genes SMN Protein SMN1 SMN2 Back up SMN Genes SMN Protein SMN1 SMN2 Back up AVXS-101 Primary Functional SMN Protein Not-functional SMN Protein

Our Solution: AVXS-101 An Innovative Treatment Approach for SMA 9 scAAV ITR Continuous Promoter Human SMN Transgene scAAV ITR KEY COMPONENTS PURPOSE Recombinant AAV9 Capsid Shell Ability to deliver across the blood brain barrier (BBB) and into the spinal cord - Avoids the need for intrathecal delivery when treating infants Non-replicating virus does not modify the existing DNA of the patient. scAAV ITR (Self-complementary DNA technology) Enables rapid onset of effect which is key in a quickly deteriorating population Continuous Promoter Activates the transgene to allow for continuous and sustained SMN expression Human SMN Transgene Full copy of a stable, functioning SMN gene that is introduced into the cell’s nucleus Recombinant AAV9 Capsid Shell Rendering adapted from DiMattia et al. Structural Insight into the Unique Properties of Adeno-Associated Virus Serotype 9. J. Virol. June 2012. Gene therapy is the right approach for SMA: Monogenic mutation that drives the pathology

Clinical Study Closeout – January 20, 2017 10 TRIAL OVERVIEW Route of Administration One-time intravenous infusion through peripheral limb vein Prednisolone 1 mg/kg 1 day Pre-GT Trial Design Open-label, dose-escalation scAAV9.CB.SMN Principal Investigator Jerry R. Mendell, M.D. AVXS-101 PHASE 1 TRIAL OVERVIEW – SMA TYPE 1 Study Site OBJECTIVES Primary Safety and Tolerability Secondary Time from birth until death or time to ≥16-hour ventilation continuously for ≥2 weeks in the absence of an acute reversible illness or perioperatively Video confirmed achievement of ability to sit unassisted* Additional CHOP INTEND Bayley Motor Scales of Infant/Toddler development – Gross Motor OBJECTIVES OBJECTIVES Inclusion 9 months of age / 6 months of age¹ and younger at day of vector infusion with SMA Type 1 as defined by the following features: Bi-allelic SMN1 gene deletion or point mutations All enrolled patients carry bi-allelic SMN1 deletions, confirmed by independent laboratory 2 copies of SMN2 Onset of disease at birth to 6 months of age Hypotonia by clinical evaluation with delay in motor skills, poor head control, round shoulder posture and hypermobility of joints Exclusion Active viral infection (includes HIV or serology positive for hepatitis B or C) Use of invasive ventilatory support (tracheotomy)* or pulse oximetry <95% saturation Patients with Anti-AAV9 antibody titers >1:50 as determined by ELISA binding immunoassay Abnormal laboratory values considered to be clinically significant Patients with the c.859G>C mutation in SMN2 exon 7 (predicted mild phenotype)2 Key Enrollment Criteria Clinicaltrials.gov Identifier = NCT02122952 ¹ Inclusion criteria was 9 months of age and younger for the first nine patients. 6 months of age and younger for the last six patients. 2 Exclusion criteria related to c.859G>C was confirmed for all patients by an independent laboratory. *Patients may be put on non-invasive ventilatory support (BiPAP) for <16 hours/day at discretion of their physician or study staff. *key developmental milestone achievements assessed and adjudicated by external independent reviewer

Event-Free Survival Data – January 20, 2017 11 * A month is defined as 30 days Cohort 1 6.7E13 vg/kg sc.AAV9.CB.SMN Cohort 2 2.0E14 vg/kg sc.AAV9.CB.SMN PNCR (Finkel) 2014 Natural History Study: 75% event-free 50% event-free 25% event-free 8% event-free Age at Last Follow-up Cohort 1*: 30.8 months (median) 30.4 months (mean) Cohort 2*: 20.2 months (median) 20.7 months (mean) *reflects age at Last Trial Visit or most recent pulmonary assessment, E.02’s age at Pulmonary Event Day of Gene Transfer Last Trial Visit – Age Fixed Pulmonary Event – Age Fixed SURVIVAL DATA 9/9 reached 20 mo. event-free (8% PNCR) 15/15 reached 13.6 mo. event-free (25% PNCR) 15/15 reached 10.5 mo. event-free (50% PNCR) 15/15 reached 8.1 mo. event-free (75% PNCR) 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 Age (months*)

CHOP INTEND vs. Age – January 20, 2017 12 COHORT 1 (n=3) Baseline Age (months): 5.9 [median], 6.3 [mean] Current Age (months): 30.8 [median], 30.4 [mean] Mean CHOP INTEND Increase: 7.7 points COHORT 2 (n=12) Baseline Age (months): 3.1 [median], 3.4 [mean] Current Age (months): 20.2 [median], 20.7 [mean] Mean CHOP INTEND Increase: 24.7 points Dashed line denotes missed or partial CHOP-INTEND assessments Rapid Response in Cohort 2 CHOP INTEND Increase at Month 1: 9.8 [mean] CHOP INTEND Increase at Month 3: 15.4 [mean] Early intervention and dose appear to affect response 0 10 20 30 40 50 60 0 3 6 9 12 15 18 21 24 27 30 CHOP INTEND Scores Age (months) 1 month = 30 days E.01 E.02 E.03 E.04 E.05 E.06 E.07 E.08 E.09 E.10 E.11 E.12 E.13 E.14 E.15

Finkel et al. Observational Study of Spinal Muscular Atrophy Type I and Implications for Clinical Trials. Neurology. August 2014. SMA Type 1 Children Typically Require Significant Nutritional and Respiratory Supportive Care By 12 Months Of Age Nearly all Type 1 patients require nutritional support by 12 mos of age1 NUTRITIONAL SUPPORT Most Type 1 patients require respiratory support by 12 mos of age1 RESPIRATORY SUPPORT BULBAR MUSCLE FUNCTION Most patients are not able to swallow or speak effectively NATURAL HISTORY FOR SMA TYPE 1 NUTRITIONAL SUPPORT STATUS OF PROPOSED THERAPEUTIC DOSE COHORT 6 of 7 (86%) that did not require feeding support before dosing continue without nutritional support RESPIRATORY SUPPORT STATUS OF PROPOSED THERAPEUTIC DOSE COHORT 7/10 (70%) that did not require BiPAP support before dosing continue without any BiPAP No children hospitalized for respiratory illnesses required a tracheostomy or prolonged invasive ventilation. BULBAR MUSCLE FUNCTION OF PROPOSED THERAPEUTIC DOSE COHORT 11/12 (92%) patients are feeding orally, including 6 exclusively fed by mouth 8/12 (67%) patients are able to speak COHORT 2 RECEIVING THE PROPOSED THERAPEUTIC DOSE OF AVXS-101

SAFETY AND TOLERABILITY OBSERVATIONS No new treatment-related SAEs or AEs observed As previously reported, a total of 5 treatment-related AEs in 4 patients have been reported following monitoring and source verification Treatment-related SAEs and AEs were clinically asymptomatic elevated liver function enzymes (LFEs) assessed under CTCAE on the basis on laboratory values and resolved with prednisolone treatment* 2 were SAEs experienced by 2 patients 3 were AEs experienced by 2 patients A total 256 AEs (5 treatment-related AEs and 251 non-treatment related AEs) have been reported following monitoring and source verification 52 SAEs and 204 non-serious AEs 65 AEs have occurred since September 15, 2016 10 disease-related SAEs in 3 patients have occurred since September 15, 2016 AVXS-101 appears to have a favorable safety profile and appears to be generally well-tolerated in patients studied to date Safety Data – January 20, 2017 14 *No drug-induced liver injury (DILI) as defined by Hy’s Law

Children with SMA Type 1 Never Sit Unassisted 15 DISEASE CHARACTERISTICS Disease onset <6 months Hypotonia and weakness Bulbar muscle weakness Difficulty breathing and swallowing Inexorable progression to nutritional failure Inexorable progression to respiratory failure DEVELOPMENTAL MILESTONE PROGNOSIS Progressive decline in motor function soon after birth Rapid loss of any early milestones (e.g. head control, hands to mouth) Will never be able to sit unassisted Will never be able to roll Will never be able to crawl, stand, or walk The Natural History of SMA Type 1 is marked by the inability to achieve or maintain developmental milestones

Motor Milestone Achievements in Cohort 2 16 Cohort 2 2.0e14 vg/kg Age at GT (mos) Motor Milestone Achievement Brings hand to mouth Head control Partial Rolla Rollb Sitting with assistance Sitting Unassisted ≥ 5 secondsc ≥ 10 secondsd ≥ 30 secondse E.04 6 E.05 4 E.06 2 E.07 4 E.08 8 E.09 5 E.10 1 E.11 2 E.12 3 E.13 1 E.14 4 E.15 2 a a a a O a O O a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a O a a a a a O a a O Two children crawl, pull to a stand, and stand and walk independently. *Milestone achievements as of January 20, 2017, except those indicated by O, which were achieved after the January 20, 2017 cutoff. Bayley Scales of Infant and Toddler Development, item #20, rolls a minimum 180o from back in only one direction. Bayley Scales of Infant and Toddler Development, item #20, rolls a minimum 180o from back to both left and right. Sitting unassisted for ≥5 seconds is in accordance with the criteria of item 22 in the Bayley Scales of Infant and Toddler Development – gross motor subtest and surpasses the three second count used as a basis for sitting (test item 1) in the Hammersmith Functional Motor Scale – Expanded for SMA (HFMSE). Sitting unassisted for ≥10 seconds is in accordance with the criteria in the World Health Organization – MultiCentre Growth Reference Study. Sitting unassisted for ≥30 seconds defines functional independent sitting and is in accordance with the criteria of item 26 in the Bayley Scales of Infant and Toddler Development – gross motor subtest.

Cohort 2 Achieved Motor Milestones Not Seen in the Natural History of SMA Type 1 17

AVXS-101 was delivered via Intracerebroventricular (ICV) injection in the mouse model for SMA (SMND7 mouse) to evaluate phenotypic rescue The scAAV9-Green Fluorescent Protein (scAAV9-GFP) was used to evaluate transgene/AAV9-biodistribution and was delivered via ICV injection in mice and intrathecal sacral infusion incynomolgus macaques DESIGN ICV delivery of AVXS-101 in mice demonstrate improved survival in the SMA mouse CSF delivery of gene therapy utilizing the AAV9 viral vector combined with tilting (Trendelenburg position) allows widespread transgene transduction in the brain, brain stem, cerebellum and upper spinal cord segments of nonhuman primates Tilting resulted in an increase in the transduction of motor neurons in the brain stem, cerebellum and upper spinal cord segments These data offer insight into vector distribution and its correlation with transgene expression and provides guidance for future AAV9-based clinical trials in SMA, as well as other neurodegenerative disorders CONCLUSIONS A Dose-response Study in Mice and Nonhuman Primates data regarding a dose-response study for the CSF delivery of AVXS-101 Brian Kaspar, PhD, Senior Vice President and Chief Scientific Officer CSF Delivery of AAV9-mediated Gene Therapy for SMA 18

Most patients (13/16) did not exhibit elevated antibody titers prior to gene replacement therapy Consistent with the literature, AAV9 antibody seropositivity under the age of 10 appears rare When positive in young children, titers are typically low AAV9 seropositivity increases after age 40, especially in women 2 of 3 patients with initial titers >1:50 were retested and able to participate in the clinical trial In the uncommon instance where both mother and child expressed antibodies against AAV9, breast-feeding was discontinued A decrease in antibody titers to 1:50 or less was seen on retesting Data suggest pre-existing antibodies to AAV9 are quite uncommon in the pediatric population, and will not impact use of gene therapy for the vast majority of SMA Type 1 patients CONCLUSIONS AVXS-101 Phase 1 Gene Therapy Clinical Trial in SMA Type 1: Experience with Preexisting Anti-AAV9 Antibody in the SMA1 Population Douglas Sproule, MD, Vice President of Clinical Development and Medical Affairs Experience with Preexisting Anti-AAV9 Antibody in the SMA Type 1 Population 19

Regardless of age at dosing and baseline motor function, most of Cohort 2 has achieved the ability to sit unassisted In Cohort 2 (proposed therapeutic dose), 11/12 patients have surpassed a CHOP-INTEND score of 40, 10/12 have surpassed a score of 50, and 2/12 have achieved the max score Natural History studies documented that by 6 months of age, almost no SMA1 child achieves a CHOP-INTEND Score of 40 Rapid improvements in CHOP-INTEND scores were observed in Cohort 2 at 1 month (9.8 points) and 3 months (15.4 points) post-dosing Most patients (9/12) in Cohort 2 are sitting unassisted Untreated children with SMA1 do not achieve major motor milestones, including sitting unassisted The degree of treatment outcomes appear to be influenced by age at dosing and baseline motor function Two children (proposed therapeutic dose) early in age and early in disease progression achieved sitting unassisted within the range of general developmental timelines These data highlight the potential impact of expeditious treatment upon diagnosis and emphasize the need for newborn screening in SMA CONCLUSIONS AVXS-101 Phase 1 Gene Therapy Clinical Trial in SMA Type 1: Correlation between CHOP-INTEND & Motor Milestone Achievements Linda Lowes, PT, PhD, Director of Clinical Therapies Research and a member of the Center for Gene Therapy at the Research Institute of Nationwide Children’s Hospital Correlation between CHOP-INTEND and Motor Milestone Achievements 20

All patients are alive and ≥15 mos of age (6 are >2 years old) All patients reached 13.6 months of age free of permanent ventilation The published natural history shows that only 25% of SMA Type 1 patients survive to 13.6 months of age without permanent ventilation 9 of 12 patients in Cohort 2 sat unassisted and 5 of 12 sat unassisted for ≥30 sec Data Update (post-Jan 20): 10 of 12 patients sat unassisted and 8 of 12 sat unassisted for ≥30 sec 11 of 12 patients in Cohort 2 achieved head control and sitting with support 2 patients in Cohort 2 crawled, stood and walked independently The published natural history shows that no SMA Type 1 patients achieve any major motor milestones 11 of 12 patients feed orally, including 6 exclusively fed by mouth 7 of 10 patients that did not require BiPAP support before dosing continue without any BiPAP 8 of 12 patients in Cohort 2 are speaking The published natural history shows that most SMA Type 1 patients require nutritional support and most require respiratory support by 12 months of age AVXS-101 appears to have a favorable safety profile and to be generally well tolerated Clinically asymptomatic elevated liver enzymes were the only treatment-related SAEs/AEs and were managed with a prednisolone regimen CONFIDENTIAL – Do not distribute Summary: AVXS-101 Phase 1 Study in SMA Type 1 21

Company Milestones 22 Type 1 Program Type 2 Program 2017 Manufacturing Q2 2017: Initiate SMA Type 1 pivotal trial in U.S.* Q1 2017: Provide update on EU regulatory pathway and trial design feedback Q2 2017: Anticipated update/minutes from CMC Type B meeting Q1 2017: 13.6 months of data for all patients in the Phase 1 trial Q2 2017: Initiate Phase 1 safety and dosing study in SMA Type 2 via intrathecal (IT) delivery* Q2/Q3 2017: End-of-Phase 1 meeting with FDA Q2 2017: Conduct a comprehensive clinical program review with EMA 2H 2017: Initiate SMA Type 1 pivotal trial in EU* *Assumes positive outcome of CMC Type B meeting

Thank You

EX-99.2

Exhibit 99.2

Media Inquiries:

Lauren Barbiero

W2O Group

646-564-2156

lbarbiero@w2ogroup.com

Investor Inquiries:

Jim Goff

AveXis, Inc.

650-862-4134

jgoff@avexis.com

AveXis Presents Results from Phase 1 Trial of AVXS-101 in SMA Type 1 at the Annual Meeting of the American Academy of Neurology

— 10 of 12 patients on proposed therapeutic dose sat unassisted; patient videos demonstrate motor milestone achievement not seen in natural history of disease —

— 86% of patients without feeding support and 70% of patients without respiratory support prior to dosing continue without any support —

— 92% of patients on proposed therapeutic dose fed orally —

— Conference call and webcast April 25 at 4:30 p.m. EDT —

Boston, Mass. (April 25, 2017) — AveXis, Inc. (NASDAQ: AVXS), a clinical-stage gene therapy company developing treatments for patients suffering from rare and life-threatening neurological genetic diseases, today presented results from the closeout of the Phase 1 trial of AVXS-101 in spinal muscular atrophy (SMA) Type 1 at the 2017 Annual Meeting of the American Academy of Neurology (AAN) in Boston. These data were presented during the Clinical Trial Plenary Session by Jerry Mendell, MD, principal investigator in the trial and Curran-Peters Chair of Pediatric Research, Professor of Pediatrics and Neurology at the Research Institute at Nationwide Children’s Hospital and The Ohio State University, Columbus, Ohio.

“Topline data from the Phase 1 study underscore the broad and consistent clinically transformative effect AVXS-101 appears to have on central nervous system and systemic features of SMA Type 1,” said Sean Nolan, President and Chief Executive Officer of AveXis. “These include event-free survival, motor function, pulmonary and nutritional support and achievement of developmental milestones — all of which are never seen in the well-characterized natural history of the disease.”

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Results from the Phase 1 Trial of AVXS-101 in SMA Type 1 as Presented at AAN

The Phase 1, open-label, dose-escalating study was designed to evaluate the safety and tolerability of AVXS-101 in patients with SMA Type 1. The key measures of efficacy were the time from birth to an “event,” which was defined as either death or at least 16 hours per day of required ventilation support for breathing for 14 consecutive days in the absence of acute reversible illness or perioperatively, and video confirmed achievement of ability to sit unassisted. Additionally, several exploratory objective measures were assessed, including a standard motor milestone development survey and Children’s Hospital of Philadelphia Infant Test of Neuromuscular Disorders (CHOP INTEND).

Event-free Survival and Safety

·Data as of January 20, 2017, showed no new events, and 15 of 15 (100%) were patients event-free at 13.6 months. The expected event-free survival rate at 13.6 months based on the natural history of the disease is 25%. The median age at last follow-up was 20.2 months and 30.8 months for patients in the proposed therapeutic-dose cohort (Cohort 2) and low-dose (Cohort 1) respectively.

·AVXS-101 appeared to have a favorable safety profile and to be generally well tolerated, with no new treatment-related safety or tolerability concerns identified.

Nutritional and Respiratory Support

·According to natural history, nearly all Type 1 patients require nutritional and respiratory support by 12 months of age, and most SMA Type 1 babies are not able to swallow or speak effectively.

·As of January 20, 2017, six of seven (86%) patients in Cohort 2 that did not require feeding support before treatment continued without feeding support after treatment; seven of 10 (70%) patients that did not require bi-level positive airway pressure (BiPAP) support before treatment continued without any BiPAP after treatment.

·Further, as of January 20, 2017, 11 of 12 (92%) patients in Cohort 2 were fed orally, and six of 12 (50%) patients were exclusively fed orally; and eight of 12 (67%) patients were able to speak.

Motor Milestone Achievement

·As of January 20, 2017, 11 of 12 patients (92%) in Cohort 2 achieved head control, nine of 12 patients (75%) could roll a minimum of 180 degrees from back to both left and right, and 11 of 12 patients (92%) could sit with assistance.

·For the end-of-study assessment, AveXis evaluated three validated and well-established measures of sitting unassisted for periods of increasing duration. As of January 20, 2017, nine of 12 patients (75%) in Cohort 2 could sit unassisted for at least five seconds, seven of 12 patients (58%) could sit unassisted for at least 10 seconds and five of 12 patients (42%) could sit unassisted for 30 seconds or more.

·Dr. Mendell today reported three patients in Cohort 2 have achieved additional sitting unassisted milestones since the January 20, 2017 evaluation date. Ten of 12 patients (83%) in Cohort 2 could sit unassisted for at least five seconds, nine of 12 (75%) patients could sit unassisted for at least 10 seconds and eight of 12 patients (67%) could sit unassisted for 30 seconds or more in the post-January 20 analysis.

·As of January 20, 2017, two patients in Cohort 2 could crawl, pull to a stand, and stand and walk independently.

·For the end-of-study assessment, all motor milestone achievements were assessed and adjudicated by an independent third-party reviewer using video evidence. The post-

2

January 20 developmental milestones were confirmed internally by video. Detailed Cohort 2 motor milestone data is included in the chart below.

		Motor Milestone Achievement as of January 20, 2017*
							Sitting Unassisted
Cohort 2 2.0e14 vg/kg	Age at Gene Transfer (mos)	Brings Hand to Mouth	Head Control	Partial Roll(a)	Roll(b)	Sitting with Assistance	>5 seconds(c)	>10 seconds(d)	>30 seconds(e)
E.04	6	X	X	X	X	X	X
E.05	4	X	X	X	X	X	X	X	X
E.06	2	X	X	X	X	X	X	X	X
E.07	4	X	X	X	X	X	X	X
E.08	8	X
E.09	5	X	X	X	X	X	X	X	X
E.10	1	X	X	X	X	X	X	X	X
E.11	2	X	X	X	X	X	X	O	O
E.12	3	X	X	X	X	X	X	X	X
E.13	1	X	X			X	X	X	O
E.14	4	X	X	X	X	X	O	O	O
E.15	2	X	X			X

(a)Bayley Scales of Infant and Toddler Development, item #20, rolls a minimum 180° from back in only one direction.

(b)Bayley Scales of Infant and Toddler Development, item #20, rolls a minimum 180° from back to both left and right.

(c)Sitting unassisted for >5 seconds is in accordance with the criteria of item 22 in the Bayley Scales of Infant and Toddler Development — gross motor subtest and surpasses the three-second count used as a basis for sitting (test item 1) in the Hammersmith Functional Motor Scale — Expanded for SMA (HFMSE).

(d)Sitting unassisted for >10 seconds is in accordance with the criteria in the World Health Organization — MultiCentre Growth Reference Study.

(e)Sitting unassisted for >30 seconds defines functional independent sitting and is in accordance with the criteria of item 26 in the Bayley Scales of Infant and Toddler Development — gross motor subtest.

*Milestone achievements as of January 20, 2017, except those indicated by an O, which were achieved after the January 20, 2017 cutoff.

“Babies born with SMA Type 1 that are untreated will never reach or maintain developmental milestones, which is why the videos presented today at AAN showing the achievement of motor milestones after a one-time infusion of AVXS-101 — including the majority of patients in Cohort 2, the proposed therapeutic-dose cohort, who were able to roll and sit unassisted — is incredibly remarkable,” said Dr. Mendell. “Importantly, AVXS-101 appears to demonstrate continued improvements past 13.6 months of age, with three new patients reaching sitting thresholds since the January 20, 2017, evaluation date.”

Research Presented at AAN Further Scientific Understanding of AVXS-101
Brian Kaspar, PhD, Senior Vice President and Chief Scientific Officer of AveXis, will present his poster today, “CSF Delivery of AAV9-mediated Gene Therapy for SMA, a Lethal Neuromuscular Disease in Children: A Dose-response Study in Mice and Nonhuman Primates — data regarding a dose-response study for the CSF delivery of AVXS-101,” data from which support the use of intrathecal delivery of gene therapy for neurological diseases, such as SMA Types 2 and 3. The study offers insight into vector distribution and its correlation with transgene expression and provides guidance for future AAV9-based clinical trials in SMA, as well as other neurodegenerative disorders.

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Douglas Sproule, MD, Vice President of Clinical Development, and Medical Affairs of AveXis, presented, “AVXS-101 Phase 1 Gene Therapy Clinical Trial in SMA Type 1: Experience with Preexisting Anti-AAV9 Antibody in the SMA1 Population,” results of which suggest pre-existing antibodies to AAV9 are quite uncommon in the pediatric population and will not impact use of gene therapy for the vast majority of SMA Type 1 patients. Two patients in the Phase 1 study who had modestly elevated anti-AAV9 titers, presumably resulting from maternal antibody transfer through breastfeeding or placental-transfer, showed resolution at retesting that enabled dosing.

Linda Lowes, PT, PhD, Director of Clinical Therapies Research and a member of the Center for Gene Therapy at the Research Institute of Nationwide Children’s Hospital, presented, “AVXS-101 Phase 1 Gene Therapy Clinical Trial in SMA Type 1: Correlation between CHOP-INTEND and Motor Milestone Achievements,” providing further evidence of the correlation between motor function and motor milestone achievement in patients with SMA Type 1. Specifically, this data demonstrates that the degree of treatment outcome appears to be influenced by age at dosing and baseline motor function.

Today’s Conference Call Information

AveXis will host a conference call and webcast at 4:30 p.m. EDT today, April 25, to discuss these data.

Analysts and investors can participate in the conference call by dialing (844) 889-6863 for domestic callers and (661) 378-9762 for international callers, using the conference ID 10345273. The webcast can be accessed live on the Events and Presentations page in the Investors and Media section of the AveXis website, www.AveXis.com.  The webcast will be archived on the company’s website until its next quarterly earnings call and will be available for telephonic replay for 14 days following the call by dialing (855) 859-2056 (Domestic) or (404) 537-3406 (International), conference ID 10345273.

About the Phase 1 Trial Design

The Phase 1 open-label, dose-escalation clinical trial of AVXS-101 in patients with SMA Type 1 initiated in April 2014. Enrollment of 15 patients across two dosing cohorts was completed in December 2015. Patients received a one-time intravenous infusion of AVXS-101 over a one-hour period in a peripheral limb vein.

Patients in Cohort 1, the low-dose cohort (n=3), received 6.7E13 vg/kg. Patients in Cohort 2, the proposed therapeutic dose cohort (n=12), received 2.0E14 vg/kg. Key inclusion criteria included SMA Type 1 patients with clinical symptoms before six months of age, bi-allelic SMN1 gene deletions or point mutations and with two copies of the SMN2 backup gene, as determined by genetic testing. Of note, all patients in the trial had bi-allelic Exon 7 deletions in SMN1. A key exclusion criteria was the presence of c.859G>C point mutation in SMN2 (Exon 7 modifier). Additionally, patients must have been no older than nine months of age (for the first nine patients) and six months of age (for the last six patients) at the time of vector infusion.

The primary outcome measure of the Phase 1 trial was safety and tolerability. The key measures of efficacy were time from birth to an “event,” which was defined as either death or at least 16 hours per day of required ventilation support for breathing for 14 consecutive days in the absence of acute reversible illness or perioperatively, and video confirmed achievement of ability to sit unassisted. Additionally, several exploratory objective measures were assessed, including a standard motor milestone development survey and Children’s Hospital of Philadelphia Infant Test of Neuromuscular Disorders (CHOP INTEND).

The primary analysis for efficacy was assessed in January 2017 when all patients reached 13.6 months of

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age. A follow-up safety analysis will be completed when the last patient reaches 24 months post-dose.

About SMA

SMA is a severe neuromuscular disease characterized by the loss of motor neurons leading to progressive muscle weakness and paralysis. SMA is caused by a genetic defect in the SMN1 gene that codes SMN, a protein necessary for survival of motor neurons. The incidence of SMA is approximately one in 10,000 live births. SMA is the leading genetic cause of infant mortality.

The most severe form of SMA is Type 1, a lethal genetic disorder characterized by motor neuron loss and associated muscle deterioration, which results in mortality or the need for permanent ventilation support before the age of two for greater than 90 percent of patients.

About AVXS-101

AVXS-101 is a proprietary gene therapy candidate of a one-time treatment for SMA Type 1 and is designed to address the monogenic root cause of SMA and prevent further muscle degeneration by addressing the defective and/or loss of the primary SMN1 gene. AVXS-101 also targets motor neurons, providing rapid onset of effect and crosses the blood brain barrier allowing an IV dosing route and effective targeting of both central and systemic features.

About AveXis, Inc.

AveXis is a clinical-stage gene therapy company developing treatments for patients suffering from rare and life-threatening neurological genetic diseases. The company’s initial proprietary gene therapy candidate, AVXS-101, recently completed a Phase 1 clinical trial for the treatment of SMA Type 1. For additional information, please visit www.avexis.com.

Forward-Looking Statements

This press release contains “forward-looking statements,” within the meaning of the Private Securities Litigation Reform Act of 1995, regarding, among other things, AveXis’ research, development and regulatory plans for AVXS-101, including the potential of AVXS-101 to positively impact quality of life and alter the course of disease in children with SMA Type 1 and statements about the effects of SMA Type 1 on developmental milestones. Such forward-looking statements are based on current expectations and involve inherent risks and uncertainties, including factors that could delay, divert or change any of them, and could cause actual results to differ materially from those projected in its forward-looking statements. Meaningful factors which could cause actual results to differ include, but are not limited to, the scope, progress, expansion, and costs of developing and commercializing AveXis’ product candidates; regulatory developments in the U.S. and EU, as well as other factors discussed in the “Risk Factors” and the “Management’s Discussion and Analysis of Financial Condition and Results of Operations” section of AveXis’ Annual Report on Form 10-K for the year ended December 31, 2016, filed with the SEC on March 16, 2017. In addition to the risks described above and in the Annual Reports on Form 10-K, Quarterly Reports on Form 10-Q, Current Reports on Form 8-K and other filings with the SEC, other unknown or unpredictable factors also could affect AveXis’ results. There can be no assurance that the actual results or developments anticipated by AveXis will be realized or, even if substantially realized, that they will have the expected consequences to, or effects on, AveXis. Therefore, no assurance can be given that the outcomes stated in such forward-looking statements and estimates will be achieved.

All forward-looking statements contained in this press release are expressly qualified by the cautionary statements contained or referred to herein. AveXis cautions investors not to rely too heavily on the

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forward-looking statements AveXis makes or that are made on its behalf. These forward-looking statements speak only as of the date of this press release (unless another date is indicated). AveXis undertakes no obligation, and specifically declines any obligation, to publicly update or revise any such forward-looking statements, whether as a result of new information, future events or otherwise, except as required by law.

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