AB Sustainable Global Thematic Fund Inc.

10/15/2026 | Press release | Distributed by Public on 10/15/2026 15:24

Prospectus by Investment Company (Form 497)

SUP-MULTI-1026

AB EQUITY FUNDS ("Equity Funds")

- ABSustainable Global Thematic Fund

Class A (Ticker: ALTFX); Class C (Ticker: ATECX); Advisor Class (Ticker: ATEYX);

Class I (Ticker: AGTIX); Class Z (Ticker: ATEZX)

- AB Sustainable International ThematicFund

Class A (Ticker: AWPAX); Class C (Ticker: AWPCX); Advisor Class (Ticker: AWPYX);

Class I (Ticker: AWPIX); Class Z (Ticker: AWPZX)

AB VARIABLE PRODUCTS SERIES FUND, INC. ("AVP")

- AB VPS Sustainable Global Thematic Portfolio

Class A; Class B

Each of the funds listed above is hereinafter referred to as a "Fund" or, collectively, the "Funds."

Supplement dated October 15, 2026 to the following Prospectuses and Summary Prospectuses, as amended:

Prospectus Date

Equity Funds

October 31, 2025

AVP

May 1, 2026

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Effective immediately, the following replaces certain information under the heading "Portfolio Managers" in the summary sections of the Prospectuses and Summary Prospectuses for the following Funds.

AB Sustainable Global Thematic Fund

PORTFOLIO MANAGERS

The following table lists the persons responsible for day-to-day management of the Fund's portfolio:

Employee Length of Service Title

Edward Bryan

Since February 2026 Senior Vice President of the Adviser

Lei Qiu

Since October 2026 Senior Vice President of the Adviser

Adam Yee

Since October 2026 Senior Vice President of the Adviser

AB Sustainable International Thematic Fund

PORTFOLIO MANAGERS

The following table lists the persons responsible for day-to-day management of the Fund's portfolio:

Employee Length of Service Title

Edward Bryan

Since February 2026

Senior Vice President of the Adviser

Lei Qiu

Since October 2026

Senior Vice President of the Adviser

Adam Yee

Since October 2026

Senior Vice President of the Adviser

AB VPS Sustainable Global Thematic Portfolio

PORTFOLIO MANAGERS

The following table lists the persons responsible for day-to-day management of the Portfolio's portfolio:

Employee Length of Service Title

Edward Bryan

Since February 2026

Senior Vice President of the Adviser

Lei Qiu

Since October 2026

Senior Vice President of the Adviser

Adam Yee

Since October 2026

Senior Vice President of the Adviser

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The following replaces certain information under the heading "Management of the [Funds/Portfolios] - Portfolio Managers" in the Prospectuses for the following Funds.

AB Sustainable Global Thematic Fund

Employee; Length of Service; Title Principal Occupation(s)
During the Past Five (5) Years
Edward Bryan; since February 2026; Senior Vice President of the Adviser Senior Vice President of the Adviser, with which he has been associated since prior to 2021.
Lei Qiu; since October 2026; Senior Vice President of the Adviser Senior Vice President of the Adviser, with which she has been associated since prior to 2021. She is also Head of Thematic Equities.
Adam Yee; since October 2026; Senior Vice President of the Adviser Senior Vice President of the Adviser, with which he has been associated since prior to 2021.

AB Sustainable International Thematic Fund

Employee; Length of Service; Title Principal Occupation(s)
During the Past Five (5) Years
Edward Bryan; since February 2026; Senior Vice President of the Adviser (see above)
Lei Qiu; since October 2026; Senior Vice President of the Adviser (see above)
Adam Yee; since October 2026; Senior Vice President of the Adviser (see above)

AB VPS Sustainable Global Thematic Portfolio

Employee; Length of Service; Title Principal Occupation(s)
During the Past Five (5) Years
Edward Bryan; since February 2026; Senior Vice President of the Adviser Senior Vice President of the Adviser, with which he has been associated since prior to 2021.
Lei Qiu; since October 2026; Senior Vice President of the Adviser Senior Vice President of the Adviser, with which she has been associated since prior to 2021. She is also Head of Thematic Equities.
Adam Yee; since October 2026; Senior Vice President of the Adviser Senior Vice President of the Adviser, with which he has been associated since prior to 2021.

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Each Statement of Additional Information is revised, as applicable, to incorporate changes conforming to this Supplement.

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This Supplement should be read in conjunction with the Prospectuses and Summary Prospectuses for the Funds.

You should retain this Supplement with your Prospectus(es) for future reference.

The [A/B] Logo is a service mark of AllianceBernstein and AllianceBernstein® is a registered trademark used by permission of the owner, AllianceBernstein L.P.

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SUP-MULTI-1026

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AB Sustainable Global Thematic Fund Inc. published this content on October 15, 2026, and is solely responsible for the information contained herein. Distributed via EDGAR on October 15, 2026 at 21:24 UTC. If you believe the information included in the content is inaccurate or outdated and requires editing or removal, please contact us at [email protected]