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): August 11, 2016

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 160

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))

Item 2.02              Results of Operations and Financial Condition.

On August 11, 2016, AveXis, Inc. (the “Registrant”) issued a press release announcing the Registrant’s financial results for the quarter ended June 30, 2016, as well as information regarding a conference call to discuss these financial results and the Registrant’s recent corporate highlights and outlook, including certain information related to the Registrant’s clinical data results for AVXS-101. A copy of this press release is furnished herewith as Exhibit 99.1 to this Current Report on Form 8-K and is incorporated herein by reference.

The information in this Item 2.02 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 (the “Securities Act”), or the Exchange Act, except as expressly set forth by specific reference in such a filing.

Item 7.01              Regulation FD Disclosure.

As discussed in Item 2.02 above, the Registrant intends to present certain information related to its clinical data results for AVXS-101 during the August 11, 2016 conference call.  A copy of the slides to be presented during the call are furnished herewith as Exhibit 99.2 to this Current Report on Form 8-K and are incorporated herein by reference.

The information in this Item 7.01 of this Current Report on Form 8-K (including Exhibit 99.2) is being furnished and shall not be deemed “filed” for purposes of Section 18 of 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 or the Exchange Act, except as expressly set forth by specific reference in such a filing.

Item 9.01.             Financial Statements and Exhibits.

(d) Exhibits

Exhibit
Number	Exhibit Description
99.1	Press Release, dated August 11, 2016, titled “AveXis Reports Second Quarter 2016 Financial and Operating Results and Interim Data from Ongoing Phase 1 Trial of AVXS-101 in Spinal Muscular Atrophy Type 1.”
99.2	Slide Presentation dated August 11, 2016, titled “AVXS-101 Clinical Data Update.”

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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: August 11, 2016	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	Press Release, dated August 11, 2016, titled “AveXis Reports Second Quarter 2016 Financial and Operating Results and Interim Data from Ongoing Phase 1 Trial of AVXS-101 in Spinal Muscular Atrophy Type 1.”
99.2	Slide Presentation dated August 11, 2016, titled “AVXS-101 Clinical Data Update.”

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EX-99.1

Exhibit 99.1

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 Reports Second Quarter 2016 Financial and Operating Results and Interim Data from Ongoing Phase 1 Trial of AVXS-101 in Spinal Muscular Atrophy Type 1

— Interim data through July 1 showed no “events” —

— Continued motor function improvement with 25% of patients in the proposed therapeutic dose group in the normal range —

— FDA requested Type B Meeting to discuss SMA Type 1 clinical development pathway —

— Conference call and webcast August 11 at 4:30 p.m. EDT —

Chicago, Ill. (August 11, 2016) — AveXis, Inc. (NASDAQ: AVXS), a clinical-stage gene therapy company developing treatments for patients suffering from rare and life-threatening neurological genetic diseases, today reported financial results for the second quarter ended June 30, 2016, recent corporate highlights and upcoming milestones, and provided an update on interim data from the ongoing Phase 1 trial of AVXS-101 in spinal muscular atrophy (SMA) Type 1.

Data as of July 1, 2016 showed AVXS-101 continued to demonstrate a favorable safety profile, with no new treatment-related safety or tolerability concerns identified. All patients in both Cohort 1 (low dose) and Cohort 2 (proposed therapeutic dose) remained without an “event,” defined as death or until a patient requires at least 16 hours per day of ventilation support for breathing for greater than two weeks in the absence of an acute reversible illness, or perioperatively. Since July 1, one patient in the low-dose cohort has reached a ventilation endpoint, described in further detail below. As of July 1, the mean motor function scores in both dosing cohorts continued to increase, with 25% of patients in Cohort 2 having achieved motor function in a range considered to be normal.

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“We continue to be encouraged with this interim data for AVXS-101 and are eager to collaborate with the FDA via the breakthrough designation process to determine next steps in the development pathway for SMA Type 1, and we have submitted a Type B meeting request with the agency to facilitate this discussion,” said Sean Nolan, President and Chief Executive Officer of AveXis. “We expect several key developments in the second half of the year including the presentation of developmental milestone data from our ongoing SMA Type 1 study, providing additional clarity on the development path for the Type 1 program and we expect to initiate our initial safety and dosing study in SMA Type 2 patients.”

Interim Phase 1 Data as of July 1, 2016

·AVXS-101 appeared to have a favorable safety profile and to be generally well tolerated in patients studied, with no new treatment-related adverse events reported.

·There have been a cumulative total of 107 adverse events (AEs) reported as of July 1, 2016, 31 of which were determined to be serious adverse events (SAEs). As previously reported, two of the 31 were deemed treatment-related and consisted of clinically asymptomatic liver enzyme elevations.

·Of the cumulative total of 76 non-serious AEs reported as of July 1, 2016, three were the previously reported treatment-related elevations in liver enzymes experienced by two patients.

·All of the elevated liver enzyme AEs and SAEs were clinically asymptomatic and resolved with prednisolone treatment. There were no elevations of GGT, alkaline phosphatase or bilirubin, and Hy’s Law was not met.

·Other non-treatment-related AEs were expected and were associated with SMA.

·Mean increases in motor function compared to baseline of 9.0 points in Cohort 1 and 23.3 points in Cohort 2 in CHOP-INTEND scores were observed. The Children’s Hospital of Philadelphia Infant Test of Neuromuscular Disorders (CHOP-INTEND) is a test developed to measure motor skills of patients with SMA Type 1.

·Eleven out of 12 patients (92 percent) and 8 out of 12 patients (67 percent) in Cohort 2 had achieved CHOP-INTEND scores of at least 40 or 50 points, respectively.

·Three out of 12 patients (25 percent) in Cohort 2 achieved a score of 60, which is in a range considered to be normal.

“These data demonstrate rapid, sustained and marked improvements in motor function as measured by CHOP-INTEND,” said Suku Nagendran, MD, Senior Vice President and Chief Medical Officer, AveXis. “Compared with the data presented as of April 1, 2016, the positive impact on average motor function scores increased from 8.7 to 9.0 points and from 19.2 to 23.3 points in Cohorts 1 and 2, respectively. It appears that both dose and baseline motor function are key factors in determining the degree of treatment response. Based on our data to date, early diagnosis and treatment appear to be critical for optimal outcomes in this population.”

Protocol-Specified Ventilation Event Occurring After July 1

·The protocol defines the “permanent ventilation endpoint” as the use of at least 16 hours per day of respiratory assistance (includes non-invasive ventilatory support) continuously for greater than 2 weeks in the absence of an acute reversible illness, excluding perioperative ventilation.

·In the course of reviewing the data as of July 1, 2016, AveXis learned that one patient in Cohort 1, the low-dose group, had begun to increase use of bi-level positive airway pressure (BiPAP) in advance of surgery related to hypersalivation, a condition experienced by some SMA patients. This patient did not meet the definition of a permanent ventilation endpoint until after July 1, 2016. As a

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result, the independent Data Safety Monitoring Board (DSMB) determined that this development was not a “permanent ventilation endpoint” for the data as of July 1, 2016, but would be classified as an “event” for the next data period ending September 30, 2016. This event was determined by the DSMB to represent progression of disease and not an adverse event related to the use of AVXS-101.

Recent Highlights

·Breakthrough Therapy Designation: On July 20, 2016, AveXis reported that the U.S. Food and Drug Administration (FDA) had granted Breakthrough Therapy Designation for AVXS-101 for the treatment of SMA Type 1 in pediatric patients based on preliminary clinical results from the ongoing trial of AVXS-101. In granting the designation, the FDA indicated that as a next step that AveXis should submit a Type B meeting request to facilitate a comprehensive discussion of the development pathway. AveXis has subsequently submitted the meeting request.

·Pulmonary Support Data: On May 15, 2016, Richard Shell, MD, member of the Section of Pulmonary Medicine at Nationwide Children’s Hospital and an Associate Professor of Clinical Pediatrics at The Ohio State University College of Medicine, presented additional pulmonary support data at the International Conference of the American Thoracic Society in San Francisco.

·The interim analysis presented at the meeting demonstrated gene therapy appeared to reduce the need for ventilation support and allowed patients to successfully recover from respiratory illnesses that are often lethal to SMA Type 1 patients. None of the patients in either dosing cohort required permanent ventilation as of April 1, 2016.

·In addition, 8 of 10 (80 percent) patients on the proposed therapeutic dose of 2.0x1014 vg/kg who did not need biphasic/bi-level ventilation (BiPAP) support prior to gene therapy continued with no ventilation support. The two exceptions were children hospitalized in the first quarter of 2016 for severe respiratory illness and placed on BiPAP to aid recovery.

·Presented Interim Data at ASGCT: On May 6, 2016, Jerry Mendell, MD, director of the Center for Gene Therapy at The Research Institute at Nationwide Children’s Hospital, presented interim data as of April 1, 2016 from the ongoing Phase 1 trial of AVXS-101 for the treatment of SMA Type 1 at the 19th Annual Meeting of the American Society of Gene & Cell Therapy in Washington, D.C.

·Appointed Michael B. Johannesen to Executive Management Team: On July 5, 2016, Michael B. Johannesen was appointed Senior Vice President, General Counsel and Chief Compliance Officer. Mr. Johannesen brings to AveXis nearly 20 years of legal experience within the global pharmaceutical, medical device and healthcare products industries, and is responsible for all aspects of the company’s legal and compliance functions, as well as human resources.

Targeted Clinical Development Milestones and Presentations

·Provide quarterly updates on the ongoing Phase 1 trial of AVXS-101 in SMA Type 1.

·Initiate a Phase 1 safety and dosing study of AVXS-101 via intrathecal (IT) delivery in patients with SMA Type 2 in the second half of 2016.

·Disclose motor development milestones at a medical meeting in the second half of 2016.

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·Provide an update on the SMA Type 1 development path in the second half of 2016 after meeting with FDA.

·Report 13.6 months of data for all patients in the ongoing SMA Type 1 Phase 1 trial in the first quarter of 2017.

·Initiate pivotal trials of AVXS-101 in patients with SMA Type 1 in the United States and Europe in the first half of 2017.

Second Quarter 2016 Financial Results

·Cash Position: As of June 30, 2016, AveXis had $131.4 million in cash and cash equivalents.

·R&D Expenses: Research and development expenses were $10.4 million for the second quarter of 2016 (which included $1.3 million of stock-based compensation), compared to $7.7 million for the same period in 2015 (which included $5.8 million of stock-based compensation), an increase of $2.7 million. The increase in research and development expenses was primarily attributable to an increase in expenses necessary to support the advancement of the company’s manufacturing product development efforts, clinical and pre-clinical programs, primarily the ongoing trial of AVXS-101 in SMA Type 1, and increases in employee compensation. Partially offsetting the increase in R&D spending was lower stock-based compensation expense of $4.5 million.

·G&A Expenses: General and administrative expenses were $5.4 million for the second quarter of 2016 (which included $2.6 million of stock-based compensation), compared to $2.3 million for the same period in 2015 (which included $0.8 million of stock-based compensation), an increase of $3.1 million. The increase in general and administrative expenses was primarily attributable to an increase in employee compensation, legal and professional fees and other infrastructure costs to support the company’s overall growth, and higher stock-based compensation expense.

·Net Loss: Net loss was $15.7 million, or $0.68 per share, for the second quarter of 2016, compared to a net loss of $9.9 million, or $1.41 per share, for the second quarter of 2015.

Conference Call Information

AveXis will host a conference call and webcast at 4:30 p.m. EDT today, August 11, 2016, to discuss second quarter 2016 financial results and business updates.

Analysts and investors can participate in the conference call by dialing (877) 508-0547 for domestic callers and (281) 973-6085 for international callers, using the conference ID 57726673. 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 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 57726673.

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.

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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. SMA Type 1 is the leading genetic cause of infant mortality.

About AVXS-101

AVXS-101 is a proprietary gene therapy candidate of a one-time treatment for SMA Type 1 and is the only clinical-stage gene therapy in development for SMA. AVXS-101 is designed to address the monogenetic root cause of SMA and prevent further muscle degeneration by addressing the defective and/or loss of the primary SMN 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, is in an ongoing 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 expected timing for initiating and reporting results from ongoing and planned clinical trials, the expected timing for reporting motor development milestones and the expected timing for the company’s planned Type B meeting with the FDA. 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 ability to obtain and maintain regulatory approval of AveXis’ product candidates; the scope, progress, expansion, and costs of developing and commercializing AveXis’ product candidates; AveXis’ ability to obtain and maintain intellectual property protection for our product candidates; AveXis’ ability to establish and maintain development partnerships; AveXis’ expectations regarding federal, state and foreign regulatory requirements; regulatory developments in the United States and foreign countries, as well as other factors discussed in the “Risk Factors” and “Management’s Discussion and Analysis of Financial Condition and Results of Operations” sections of AveXis’ Annual Report on Form 10-K for the year ended December 31, 2015, filed with the SEC on March 18, 2016, the company’s Quarterly Report on Form 10-Q for the quarter ended June 30, 2016, and other reports AveXis files with the SEC. 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.

Selected Financial Information

Operating Results:

	Three Months Ended June 30						Six Months Ended June 30
	2016			2015			2016			2015
Revenue	$	—		$	—		$	—		$	—
Total revenue
Operating Expenses:
General and administrative	5,418,266			2,268,521			10,242,180			2,911,156
Research and development	10,379,521			7,654,839			26,444,610			12,466,864
Total Operating Expenses	15,797,787			9,923,360			36,686,790			15,378,020
Interest income	78,829			4,185			131,725			5,641
Net loss and comprehensive loss	$	(15,718,958	)	$	(9,919,175	)	$	(36,555,065	)	$	(15,372,379	)
Weighted-average basic and diluted common shares outstanding	23,013,838			7,030,976			19,876,850			5,045,211
Basic and diluted net loss per common share	$	(0.68	)	$	(1.41	)	$	(1.84	)	$	(3.05	)

Balance Sheet Information:

	June 30			December 31
	2016			2015
Cash and cash equivalents	$	131,432,653		$	62,251,860
Total assets	143,112,011			65,084,291
Total Liabilities	8,683,173			6,877,304
Total stockholders’ deficit	$	(95,105,586	)	$	(58,550,520	)

# # #

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EX-99.2

Exhibit 99.2

AVXS-101 Clinical Data Update August 11, 2016

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 and completion of studies or trials and related preparatory work, the period during which the results of the trials will become available 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

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 90% of SMA Type 1 patients will not survive to the age of 2 3 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

AVXS-101 Targets the Primary SMN Gene 4 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

SMA Type 1 is a Motor Neuron Disease with both Central and Systemic Features 5 Addresses underlying cause of SMA – defective/loss of primary SMN gene Targets motor neurons Provides rapid onset of effect and continuous and sustained SMN expression Crosses blood brain barrier allowing IV dosing route Effectively targets both central and systemic features CNS Heart Muscle GI tract HALLMARKS OF SMA TYPE 1 Defective/loss of SMN1 gene (primary SMN producer) Motor neurons are most susceptible to diminished SMN levels Rapid loss of motor neurons throughout brain, brain stem and spinal cord (CNS) Autonomic & systemic involvement Heart rate Swallowing Muscle (e.g. respiratory) AVXS-101

Our Solution: AVXS-101 An Innovative Treatment Approach for SMA 6 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

Phase 1 Trial Design 7 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 Principal Investigator Jerry R. Mendell, M.D. TRIAL OVERVIEW 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 without support Additional CHOP INTEND Bayley Motor Scales of Infant/Toddler development – Gross Motor Exploratory Ability Captured Through Interactive Video Evaluation-mini (ACTIVE-mini) Comp Motor Action Pot (CMAP) Motor Unit Number (MUNE) Electrical Impedance Myography (EIM) 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 mutations (deletion or point mutations) 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 with positive pressure)* 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 for the last six patients. *Patients may be put on non-invasive ventilatory support (BiPAP) for <16 hours/day at discretion of their physician or study staff

Survival Data – Ongoing Phase 1 Trial, July 1, 2016 * A month is defined as 30 days Cohort 1 6.7E13 vg/kg Cohort 2 2.0E14 vg/kg PNCR (Finkel) 2014 Natural History Study: 75% event-free 50% event-free 25% event-free 8% event-free 8 Day of Gene Transfer Last Trial Visit – Age Fixed SURVIVAL DATA 6/6 reached 20 mo. event-free (8% PNCR) 9/9 reached 13.6 mo. event-free (25% PNCR) 13/13 reached 10.5 mo. event-free (50% PNCR) 15/15 reached 8.1 mo. event-free (75% PNCR)

CHOP INTEND vs. Age: Cohort 1, July 1, 2016 Dashed line denotes missing data for reasons noted below: E.01 – follow-up on Month 17 cancelled due to SAE hospitalization; full CHOP INTEND not conducted on Months 19, 20 and 21 due to broken right arm; full CHOP INTEND not conducted on Months 26, 27, 29 and 30 due to family reasons; follow-up on Month 28 cancelled due to family reasons. E.02 – CHOP INTEND not conducted on Month 14 due to broken left leg; full CHOP INTEND not conducted on Months 23, 24, 26 and 27 due to family reasons. E.03 – follow-up on Months 17 and 18 cancelled due to SAE hospitalization; CHOP INTEND not conducted on Month 19 due to SAE recovery; CHOP INTEND not conducted on Month 22 due to family reasons; full CHOP INTEND not conducted on Months 23, 25, 26, 27 and 28 due to family reasons. E.02 E.03 E.01* 9 * E.01 completed 24 months of follow-up and age is fixed at Last Trial Visit (May 2016) 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 Baseline Age (months): 5.9 [median], 6.3 [mean] Current Age* (months): 28.8 [median], 29.3 [mean] Mean CHOP INTEND Increase: 9.0 points

CHOP INTEND vs. Age: Cohort 2, July 1, 2016 10 Dashed line denotes missing data for reasons noted below: E.04 – full CHOP INTEND not conducted on Months 14 and 15 due to body cast for scoliosis; CHOP INTEND not conducted on Month 19 due to scoliosis surgery recovery; CHOP INTEND not conducted on Month 20 due to SAE hospitalization; full CHOP INTEND not conducted on Month 21 due to SAE hospitalization; CHOP INTEND not conducted on Month 24 due to SAE hospitalization. E.06 – CHOP INTEND not conducted starting on Month 16 due to inappropriateness of assessment for age and ability. E.07 – follow-up on Months 10, 11 and 15 cancelled due to family reasons. E.08 – follow-up on Months 13, 15 and 17 cancelled due to family reasons; full CHOP INTEND not conducted on Month 18 due to left leg fracture; CHOP INTEND not conducted on Month 20 due to family reasons; CHOP INTEND not conducted on Month 21 due to SAE hospitalization. E.09 – follow-up on Month 12 cancelled due to family reasons. E.10 – CHOP INTEND not conducted on Month 11 due to inappropriateness of assessment for age and ability. E.15 – follow-up on Month 6 cancelled due to family reasons. 92% reached CHOP INTEND 40 points 67% reached CHOP INTEND 50 points 25% reached CHOP INTEND 60 points – these three patients in range considered normal, including two patients who consistently achieved the max score of 64 points Baseline Age (months): 3.1 [median] 3.4 [mean] Current Age (months): 14.8 [median] 15.4 [mean] Mean CHOP INTEND Increase: 23.3 points Mean CHOP INTEND Increase*: 24.8 points * Excludes 2 patients who achieved max score 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.04 E.05 E.06 E.07 E.08 E.09 E.10 E.11 E.12 E.13 E.14 E.15

Change in CHOP INTEND Scores – July 1, 2016 NN101 = NeuroNEXT Natural History Study CHOP INTEND decrease of 10.5 points/yr. +23.3** +9.0 -10.5 11 ** Calculation includes 2 patients who achieved max score COHORT 1 (n=3) Baseline Age (months): 5.9 [median], 6.3 [mean] Current Age* (months): 28.8 [median], 29.3 [mean] Mean CHOP INTEND Increase: 9.0 points COHORT 2 (n=12) Baseline Age (months): 3.1 [median], 3.4 [mean] Current Age (months): 14.8 [median], 15.4 [mean] Mean CHOP INTEND Increase**: 23.3 points Dashed line denotes missed or partial assessments * Current Age reflects E.01’s age at Last Trial Visit -15 -10 -5 0 5 10 15 20 25 30 35 40 0 2 4 6 8 10 12 14 16 18 20 22 24 Change in CHOP INTEND Scores Months after Study Treatment NN101 Cohort 1 Cohort 2 Cohort 1 Average Cohort 2 Average

Safety Data – Ongoing Phase 1 Trial – July 1, 2016 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 observed to date. Treatment-related SAEs and AEs were clinically asymptomatic elevated liver function enzymes (LFEs) resolved with prednisolone treatment. 2 were SAEs experienced by 2 patients (SAEs defined on the basis of laboratory tests showing elevated LFEs). 3 were AEs experienced by 2 patients. 107 confirmed AEs, 31 deemed SAEs Of the 29 unrelated SAEs, 23 were related to the pulmonary system, including 4 resolved events of respiratory syncytial virus (RSV) infections. Of the 76 non-serious AEs, all were mild or moderate in severity Other non-treatment-related AEs were expected and associated with SMA AVXS-101 appears to have a favorable safety profile and appears to be generally well-tolerated in patients studied to date 12

Summary: Ongoing Phase 1 Data – July 1, 2016 13 AVXS-101 appears to have a favorable safety profile and appears to be generally well-tolerated A total 107 AEs, 31 SAEs and 76 non-serious AEs observed to date No additional treatment-related AEs have been observed beyond the previously reported five elevated LFEs experienced by 4 patients. All were resolved following prednisolone treatment. AVXS-101 appears to have a marked and positive impact on the disease course of SMA Type 1 Cohort 1 patients (n=3) are over 20.0 months of age (100% AVXS-101 vs. <8% predicted Finkel 2014) Cohort 2 patients (n=6) are over 13.6 months of age (100% AVXS-101 vs. 25% predicted Finkel 2014) The oldest 3 patients are >20.0 months of age All patients have sustained increases in CHOP INTEND vs baseline and response appears to be dose-dependent Cohort 1 (n=3) increased an average 9.0 points from baseline 16.3 CHOP INTEND Cohort 2 (n=12) increased an average 23.3 points from baseline 28.2 CHOP INTEND Finkel 2014 observed only 1 SMA Type 1 patient transiently at >40 points 92% of Cohort 2 (11 of 12) reached CHOP INTEND 40 points 67% of Cohort 2 (8 of 12) reached CHOP INTEND 50 points 25% of Cohort 2 (3 of 12) reached CHOP INTEND 60 points 2 of these 3 patients have consistently reached the max score of 64 All patients in both dosing cohorts were without an “event,” and no new treatment-related AEs were observed First patient enrolled has completed 2-year follow-up (May 2016) In Cohort 2, the first 6 patients have reached at least 1 year post-treatment

Financial Position (dollars in millions) 14 Cash and cash equivalents of $131.4 million as of June 30, 2016 Three months ended 6/30/16 Three months ended 6/30/15 R&D Expense $10.4 $7.7 G&A Expense $5.4 $2.3 Net Loss $15.7 $9.9

Clinical Development Milestones 15 2016 2H 2016: Provide update on FDA Type B meeting Q1 2017: 13.6 months of data for all patients in the SMA Type 1 Phase 1 trial 2H 2016: Initiate Phase 1 safety and dosing study in SMA Type 2 via intrathecal (IT) delivery 1H 2017: Initiate SMA Type 1 pivotal trials in U.S. and EU Type 1 Program Type 2 Program Start of 2016: Quarterly updates on ongoing Phase 1 trial 2H 2016: Report motor development milestones 2017

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