UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

WASHINGTON, D.C. 20549

SCHEDULE 13D

Under the Securities Exchange Act of 1934

(Amendment No. 2 )*

Inozyme Pharma, Inc.

(Name of Issuer)

Common Stock, par value $0.0001 per share

(Title of Class of Securities)

45790W 108

(CUSIP Number)

Peter Haahr

Novo Holdings A/S

Tuborg Havnevej 19

Hellerup, Denmark DK-2900

+45 3527 6592

Copy to:

B. Shayne Kennedy, Esq.

Latham & Watkins LLP

650 Town Center Drive, 20^th Floor

Costa Mesa, CA 92626

Telephone: (714) 540-1235

(Name, Address and Telephone Number of Person Authorized to Receive Notices and Communications)

January 28, 2021

(Date of Event which Requires Filing of this Statement)

If the filing person has previously filed a statement on Schedule 13G to report the acquisition which is subject of this Schedule 13D, and is filing this statement because of Rule 13d-1(e), 13d-1(f) or 13d-1(g), check the following box.  ☐

Note: Schedules filed in paper format shall include a signed original and five copies of the schedule, including all exhibits. See Rule 13d-7(b) for other parties to whom copies are to be sent.

The information required on the remainder of this cover page shall not be deemed to be “filed” for the purpose of Section 18 of the Securities Exchange Act of 1934 (the “Act”) or otherwise subject to the liabilities of that section of the Act but shall be subject to all other provisions of the Act (however, see the Notes).

2

This amendment (“Amendment No. 2”), amends the Schedule 13D originally filed with the Securities and Exchange Commission (“SEC”) on July 29, 2020, as subsequently amended by Amendment No. 1 filed on October 5, 2020 (collectively, the “Schedule”), to report a decrease in beneficial ownership of common stock of the Issuer held by Novo Holdings A/S resulting from the sale of shares by Novo Holdings A/S. All capitalized terms contained herein but not otherwise defined shall have the meanings ascribed to such terms in the Schedule.

Item 2 is amended and replaced in its entirety as follows:

The name of each director and executive officer of both Novo Holdings A/S and the Foundation is set forth on Schedule I to this Schedule 13D.

The residence or business address of each director and executive officer of both Novo Holdings A/S and the Foundation is set forth on Schedule I to this Schedule 13D.

The Foundation is a Danish self-governing and profit-making foundation, whose objectives are to provide a stable basis for commercial and research activities undertaken by the group of Novo companies and to support scientific, humanitarian and social purposes through grants.

Item 5(a) and (c) are amended and replaced in its entirety as follows:

(a)    Novo Holdings A/S beneficially owns 2,194,379 shares of Common Stock representing approximately 9.4% of the Issuer’s outstanding shares of Common Stock, based upon 23,372,844 shares of the Issuer’s Common Stock outstanding as of November 6, 2020, as reported in the Issuer’s 10-Q filed with the SEC on November 12, 2020.

(c)    On January 28, 2021, Novo Holdings A/S sold 375,000 shares at $21.00 per share in a block sale broker transaction. No other transactions in the Issuer’s Common Stock were effected by Novo Holdings A/S nor the Foundation nor any person listed on Schedule I to the Schedule in the Issuer’s Common Stock within the past 60 days.

3

SIGNATURE

After reasonable inquiry and to the best of my knowledge and belief, I certify that the information set forth in this statement is true, complete and correct.

Schedule I

Information regarding each director and executive officer of both Novo Holdings A/S and the Novo Nordisk Foundation is set forth below.