The remainder of this cover page shall be filled out for a reporting person’s initial filing on this form with respect to the subject class of securities, and for any subsequent amendment containing information which would alter the disclosures provided in a prior cover page.

Names of Reporting Persons

REGENXBIO Inc.

Check the Appropriate Box if a Member of a Group (See Instructions)

(a)  ☐        (b)  ☐

SEC Use Only

Citizenship or Place of Organization

Delaware

Number of

Shares

Beneficially

Owned by

Each

Reporting

Person

With

Sole Voting Power

2,030,000

Shared Voting Power

0

Sole Dispositive Power

2,030,000

Shared Dispositive Power

0

Aggregate Amount Beneficially Owned by Each Reporting Person

2,030,000

Check if the Aggregate Amount in Row (9) Excludes Certain Shares (See Instructions)

☐

Percent of Class Represented by Amount in Row (9)

5.95%⁽¹⁾

Type of Reporting Person (See Instructions)

CO

Based upon 34,102,019 shares of common stock outstanding as of November 6, 2019, as reported in the Issuer’s Quarterly Report on Form 10-Q filed with the Securities and Exchange Commission on November 12, 2019.

Name of Issuer

Address of Issuer’s Principal Executive Offices

Name of Person(s) Filing

Address of Principal Business Office or, if none, Residence

Citizenship

Title of Class of Securities

CUSIP Number

If this statement is filed pursuant to §§240.13d-1(b) or 240.13d-2(b) or (c), check whether the person filing is a:

Ownership

(a) Amount beneficially owned:

(b) Percent of class:

(c) Number of shares as to which the Reporting Person has:

(i) Sole power to vote or to direct the vote:

(ii) Shared power to vote or to direct the vote:

(iii) Sole power to dispose or to direct the disposition of:

(iv) Shared power to dispose or to direct the disposition of:

Based upon 34,102,019 shares of common stock outstanding as of November 6, 2019, as reported in the Issuer’s Quarterly Report on Form 10-Q filed with the Securities and Exchange Commission on November 12, 2019.

Ownership of Five Percent or Less of a Class

Ownership of More than Five Percent on Behalf of Another Person

Identification and Classification of the Subsidiary Which Acquired the Security Being Reported on By the Parent Holding Company or Control Person

Identification and Classification of Members of the Group

Notice of Dissolution of Group

Certification