Summary Prospectus by Investment Company (Form 497K)

Summary Prospectus January 28, 2026
Virtus International Small-Cap Fund

A: AOPAX	INSTITUTIONAL: ALOIX	R6: AIISX

Before you invest, you may want to review the fund's prospectus, which contains more information about the fund and its risks. You can find the fund's prospectus, shareholder reports, statement of additional information ("SAI"), and other information about the fund online at www.virtus.com/investor-resources/mutual-fund-documents. You can also get this information at no cost by calling 800-243-1574 or by sending an e-mail to: [email protected]. If you purchase shares of the fund through a broker-dealer or other financial intermediary such as a bank, the prospectus and other information will also be available from your financial intermediary. The fund's prospectus and SAI both dated January 28, 2026, are incorporated by reference into this Summary Prospectus.

Investment Objective

The fund seeks maximum long-term capital appreciation.

Fees and Expenses

The tables below illustrate the fees and expenses that you may pay if you buy, hold and sell shares of the fund. You may pay other fees, such as brokerage commissions and other fees to financial intermediaries, which are not reflected in the tables and examples below. You may qualify for sales charge discounts in Class A Shares if you and your family invest, or agree to invest in the future, at least $50,000 in Virtus Funds. More information on these and other discounts is available: (i) from your financial professional or other financial intermediary; (ii) under "Sales Charges" on page 59 of the fund's prospectus; and (iii) with respect to purchase of shares through specific intermediaries, in Appendix A to the fund's prospectus, entitled "Intermediary Sales Charge Discounts and Waivers."

Shareholder Fees (fees paid directly from your investment)		Class A	Institutional	Class R6
Maximum Sales Charge (load) Imposed on Purchases (as a percentage of offering price)		5.50%	None	None
Maximum Deferred Sales Charge (load) (as a percentage of the lesser of purchase price or redemption proceeds)		None	None	None
Annual Fund Operating Expenses (expenses that you pay each year as a percentage of the value of your investment)		Class A	Institutional	Class R6
Management Fees		1.00%	1.00%	1.00%
Distribution and Shareholder Servicing (12b-1) Fees		0.25%	None	None
Other Expenses		0.58%	0.55%	0.46%
Total Annual Fund Operating Expenses		1.83%	1.55%	1.46%
Less: Fee Waiver and/or Expense Reimbursement(a)		(0.58)%	(0.51)%	(0.46)%
Total Annual Fund Operating Expenses After Fee Waiver and/or Expense Reimbursement(a)		1.25%	1.04%	1.00%

(a)

The fund's investment adviser has contractually agreed to limit the fund's total operating expenses (excluding certain expenses, such as taxes, leverage and borrowing expenses (such as commitment, amendment and renewal expenses on credit or redemption facilities), interest, brokerage commissions, expenses incurred in connection with any merger or reorganization, unusual or infrequently occurring expenses (such as litigation), acquired fund fees and expenses, and dividend expenses, if any) so that such expenses do not exceed 1.25% for Class A Shares, 1.04% for Institutional Class Shares and 1.00% for Class R6 Shares through February 1, 2027. Prior to February 1, 2027, only the fund's Board may modify or terminate the expense limitation agreement. Following the contractual period, the adviser may discontinue these expense reimbursement arrangements at any time. Under certain conditions, the adviser may recapture operating expenses reimbursed and/or fees waived under these arrangements for a period of three years following the date such waiver or reimbursement occurred, provided that the recapture does not cause the fund to exceed its expense limit in effect at the time of the waiver or reimbursement, and any in effect at the time of recapture, after repayment is taken into account.

Example

This example is intended to help you compare the cost of investing in the fund with the cost of investing in other mutual funds. The example assumes that you invest $10,000 in the fund for the time periods indicated and then redeem all of your shares at the end of those periods or continued to hold them. The example also assumes that your investment has a 5% return each year, that the fund's operating expenses remain the same and that the expense reimbursement agreement remains in place for the contractual period. Although your actual costs may be higher or lower, based on these assumptions your costs would be:

Class	Share Status	1 Year		3 Years		5 Years		10 Years
Class A	Sold or Held	$670		$1,041		$1,435		$2,535
Institutional Class	Sold or Held	$106		$440		$796		$1,802
Class R6	Sold or Held	$102		$417		$754		$1,707

Portfolio Turnover

The fund pays transaction costs, such as commissions, when it buys and sells securities (or "turns over" its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when fund shares are held in a taxable account. These costs, which are not reflected in annual

fund operating expenses or in the example, affect the fund's performance. During the most recent fiscal year, the fund's portfolio turnover rate was 75% of the average value of its portfolio.

Investments, Risks and Performance

Principal Investment Strategies

The fund seeks to achieve its objective by normally investing at least 80% of its net assets (plus borrowings made for investment purposes) in companies with smaller market capitalizations. The fund currently defines companies with smaller market capitalizations as those with market capitalizations comparable to companies included in the MSCI All Country World ex USA Small-Cap Index. Under normal circumstances, the fund expects to maintain a weighted-average market capitalization between 50% and 200% of the weighted-average market capitalization of the securities in the MSCI All Country World ex USA Small-Cap Index, which as of September 30, 2025 would permit the fund to maintain a weighted-average market capitalization ranging from $1.3 billion to $5.2 billion. The fund normally invests principally in securities of issuers located outside the United States and allocates its investments among at least eight different countries. The fund may invest in emerging market securities.

Members of the portfolio management team believe that behavioral biases of investors contribute to market inefficiencies. Their quantitative investment process begins with a proprietary investment-return forecasting model which combines behavioral factors (which seek to capitalize on human behavioral biases (i.e., systematic tendencies) from financial analysts, company management and investors), with intrinsic and valuation factors (which are expected to provide tangible measures of a company's true worth). The portfolio managers integrate this multi-factor approach with a proprietary risk model to form the basis of portfolio construction, with constraints at the individual security, country and industry levels to manage exposures relative to the benchmark. Additionally, all investment recommendations are thoroughly vetted on an individual company level to confirm the investment rationale and suitability before a purchase or sale.

In addition to common stocks and other equity securities (such as preferred stocks, convertible securities and warrants), the fund may invest in securities issued in initial public offerings (IPOs), real estate investment trusts ("REITs") and may utilize foreign currency exchange contracts, options, stock index futures contracts and other derivative instruments. The fund typically does not engage in active hedging of currency but retains flexibility to do so depending on market performance. Although the fund did not invest significantly in derivative instruments as of the most recent fiscal year end, it may do so at any time.

Principal Risks

The fund may not achieve its objective(s), and it is not intended to be a complete investment program. The value of the fund's investments that supports your share value may decrease. If between the time you purchase shares and the time you sell shares the value of the fund's investments decreases, you will lose money. Investment values can decrease for a number of reasons. Conditions affecting the overall economy, specific industries or companies in which the fund invests can be worse than expected, and investments may fail to perform as the subadviser expects. As a result, the value of your shares may decrease. Purchase and redemption activities by fund shareholders may impact the management of the fund and its ability to achieve its investment objective(s). The principal risks of investing in the fund are identified below (in alphabetical order after the first six risks).

> Market Volatility Risk: The value of the securities in the fund may go up or down in response to the prospects of individual companies and/or general economic conditions. Price changes may be short- or long-term. Local, regional or global events such as war or military conflict (e.g., Russia's invasion of Ukraine), geopolitical risk, acts of terrorism, the spread of infectious illness or other public health issue, recessions, tariffs and other restrictions on trade, or the threat or potential of one or more such events and developments, could have a significant impact on the fund and its investments, including hampering the ability of the fund's portfolio manager(s) to invest the fund's assets as intended.

> Issuer Risk: The fund will be affected by factors specific to the issuers of securities and other instruments in which the fund invests, including actual or perceived changes in the financial condition or business prospects of such issuers.

> Equity Securities Risk: The value of the stocks held by the fund may be negatively affected by the financial market, industries in which the fund invests, or issuer-specific events. Focus on a particular style or in small or medium-sized companies may enhance that risk.

> Foreign Investing Risk: Investing in foreign securities subjects the fund to additional risks such as increased volatility; currency fluctuations; less liquidity; less publicly available information about the foreign investment; and political, regulatory, economic, and market risk.

> Emerging Market Risk: Emerging markets securities may be more volatile, or more greatly affected by negative conditions, than those of their counterparts in more established foreign markets. Such securities may also be subject to Sanctions Risk.

> Sanctions Risk: The imposition of sanctions and other similar measures could cause a decline in the value and/or liquidity of securities issued by or tied to the sanctioned country and increase market volatility and disruption in the sanctioned country and throughout the world. Sanctions and other similar measures could limit or prevent the fund from buying and selling securities (in the sanctioned country and other markets), significantly delay or prevent the settlement of transactions, and negatively impact the fund's liquidity and performance.

> Allocation Risk: If the fund's exposure to equities and fixed income securities, or to other asset classes, deviates from the intended allocation, or if the fund's allocation is not optimal for market conditions at a given time, the fund's performance may suffer.

> Counterparty Risk: There is risk that a party upon whom the fund relies to complete a transaction will default.

> Credit Risk: If the issuer of a debt instrument fails to pay interest or principal in a timely manner, or negative perceptions exist in the market of the issuer's ability to make such payments, the price of the security may decline.

> Currency Rate Risk: Fluctuations in the exchange rates between the U.S. dollar and foreign currencies may negatively affect the value of the fund's shares.

> Derivatives Risk: Derivatives and other similar instruments (collectively referred to in this section as "derivatives") may include, among other things, futures, options, forwards and swap agreements and may be used in order to hedge portfolio risks, create leverage or attempt to increase returns. Investments in derivatives may result in increased volatility and the fund may incur a loss greater than its principal investment.

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> Focused Investment Risk: To the extent the fund focuses its investments on a limited number of issuers, sectors, industries, geographic regions or portfolio themes, it may be subject to increased risk and volatility.

> IPO Risk: Securities purchased in initial public offerings have no trading history, limited issuer information and increased volatility.

> Leverage Risk: When the fund leverages its portfolio by borrowing or by engaging in certain types of transactions or instruments, including derivatives, the fund may be less liquid, may liquidate positions at an unfavorable time, and the volatility of the fund's value may increase.

> Liquidity Risk: Certain securities may be substantially less liquid than many other securities, such as U.S. Government securities or common stocks. To the extent the fund invests in less liquid securities or the level of liquidity in a particular market is constrained, the lack of an active market for investments may cause delay in disposition or force a sale below fair value.

> Redemption Risk: One or more large shareholders or groups of shareholders may redeem their holdings in the fund, resulting in an adverse impact on remaining shareholders in the fund by causing the fund to take actions it would not otherwise have taken. The effects of taxable gains resulting from large redemptions of fund shares would particularly impact non-redeeming shareholders who do not hold their fund shares in a tax-advantaged or tax-exempt vehicle. Such large shareholder redemptions, which may occur rapidly or unexpectedly, may cause a fund to sell portfolio securities at times when it would not otherwise do so, which may negatively impact the fund's NAV and liquidity. In addition, a large redemption could result in the fund's current expenses being allocated over a smaller asset base, leading to an increase in the fund's expense ratio.

> Real Estate Investment Risk: The fund may be negatively affected by changes in real estate values or economic conditions, credit risk and interest rate fluctuations, changes in the value of the underlying real estate and defaults by lessees and/or borrowers.

> Small and Medium Market Capitalization Companies Risk: The fund's investments in small and medium market capitalization companies may increase the volatility and risk of loss to the fund, as compared with investments in larger, more established companies.

Please see "More Information About Risks of Investing in the Funds" in the fund's prospectus for a more detailed description of the fund's risks.

Performance Information

The bar chart and table below provide some indication of the potential risks of investing in the fund. The fund's past performance, before and after taxes, is not necessarily an indication of how the fund will perform in the future.

The bar chart shows changes in the fund's performance from year to year over a 10-year period. The table shows how the fund's average annual returns compare to those of two broad-based securities market indexes. Updated performance information is available at virtus.com or by calling 800-243-1574.

Calendar year total returns for Institutional Class Shares

Returns do not reflect sales charges applicable to other share classes and would be lower if they did.

Best Quarter:	2020, Q2:	22.14%	Worst Quarter:	2020, Q1:	-24.76%

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Average Annual Total Returns (for the periods ended 12/31/25)

					Since Inception
					Class R6
Class		1 Year	5 Years	10 Years	(2/1/2016)
Institutional Class Shares
	Return Before Taxes	36.28%	5.32%	6.43%	-
	Return After Taxes on Distributions	35.04%	4.31%	5.23%	-
	Return After Taxes on Distributions and Sale of Fund Shares	22.66%	4.39%	4.99%	-
Class A Shares
	Return Before Taxes	28.50%	3.92%	5.61%	-
Class R6 Shares
	Return Before Taxes	36.37%	5.37%	-	7.37%
Index
MSCI All Country World ex USA Index (net) (reflects no deduction for fees or expenses)		32.39%	7.91%	8.41%	9.19%
MSCI All Country World ex USA Small Cap Index (net) (reflects no deduction for fees or expenses)		29.26%	6.91%	8.13%	8.96%

The MSCI All Country World ex USA Index (net) is a free float-adjusted market capitalization-weighted index that measures equity performance of developed and emerging markets, excluding the United States. The index is calculated on a total return basis with net dividends reinvested. The index is unmanaged and not available for direct investment.

The MSCI All Country World ex USA Small Cap Index (net) is a free float-adjusted market capitalization-weighted index that measures mid- and small-cap performance across 22 of 23 Developed Market countries (excluding the U.S.) and 24 Emerging Markets countries. The index is calculated on a total return basis with net dividends reinvested. The index is unmanaged and not available for direct investment.

After-tax returns are calculated using the historical highest individual federal marginal income tax rates and do not reflect the impact of state and local taxes. After-tax returns are shown only for Institutional Class Shares; after-tax returns for other classes will vary. Actual after-tax returns depend on the investor's tax situation and may differ from those shown. After-tax returns are not relevant to investors who hold fund shares in tax-deferred accounts or to shares held by non-taxable entities. In certain cases, the Return After Taxes on Distributions and Sale of Fund Shares for a period may be higher than other return figures for the same period. This will occur when a capital loss is realized upon the sale of fund shares and provides an assumed tax benefit that increases the return.

Management

The fund's investment adviser is Virtus Investment Advisers, LLC (formerly known as Virtus Investment Advisers, Inc.) ("VIA").

The fund's subadviser is Virtus Advisers-Systematic, an operating division of Virtus Advisers, LLC ("VA"), an affiliate of VIA.

Portfolio Management

The following individuals are jointly and primarily responsible for the day-to-day management of the fund's portfolio.

> Kunal Ghosh, Chief Investment Officer and Senior Managing Director, Virtus Systematic, has managed the fund since July 2022.

> Lu Yu, CFA, CIPM, Lead Portfolio Manager and Managing Director, Virtus Systematic, has managed the fund since July 2022.

Purchase and Sale of Fund Shares

Minimum initial investments applicable to Class A Shares:

 $2,500, generally

 $100 for Individual Retirement Accounts (IRAs), systematic purchase or exchange accounts

 No minimum for defined contribution plans, asset-based fee programs, profit-sharing plans or employee benefit plans.

Minimum additional investments applicable to Class A Shares:

 $100, generally

 No minimum for defined contribution plans, asset-based fee programs, profit-sharing plans or employee benefit plans.

For Institutional Class shares, the minimum initial investment in the fund is $1,000,000 and no minimum is needed to add to an existing account, though minimums may be modified for certain financial intermediaries that aggregate trades on behalf of investors.

Class R6 Shares are offered without a minimum initial investment to the following investors in plan level or omnibus accounts only (provided that they do not require or receive any compensation, administrative payments, sub-transfer agency payments or service payments with respect to Class R6 Shares): (i) qualified retirement plans, including, but not limited to, 401(k) plans, 457 plans, employer sponsored 403(b) plans, and defined benefit plans; (ii) banks and trust companies; (iii) insurance companies; (iv) financial intermediaries utilizing such shares in fee-based investment advisory programs; (v) registered investment companies; (vi) 529 portfolios that are advised or sub-advised by Virtus affiliates; and (vii) non-qualified deferred compensation plans. Other institutional investors may be permitted to purchase Class R6 Shares subject to the fund's determination of eligibility and may be subject to a $2,500,000 minimum initial investment requirement.

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The minimums may be reduced or waived in some circumstances. In general, you may buy or sell shares of the fund by mail or telephone on any business day. You also may buy and sell shares through a financial professional, broker-dealer or other financial intermediary.

Taxes

The fund's distributions are taxable to you as either ordinary income or capital gains, except when your investment is through a tax-deferred arrangement, such as a 401(k) plan or an individual retirement account. Such tax-deferred arrangements may be taxed later upon withdrawal of monies from those arrangements.

Payments to Broker-Dealers and Other Financial Intermediaries

If you purchase the fund through a broker-dealer or other financial intermediary (such as a bank), the fund and its related companies may pay the intermediary for the sale of fund shares and related services. These payments may create a conflict of interest by influencing the broker-dealer or other intermediary and your financial professional to recommend the fund over another investment.

No compensation, administrative payments, sub-transfer agency payments or service payments are paid to brokers or other entities from fund assets or the Distributor's or an affiliate's resources on sales of or investments in Class R6 Shares. Class R6 Shares do not carry sales commissions or pay Rule 12b-1 fees, or make payments to brokers or other entities to assist in, or in connection with, the sale of the fund's shares. Ask your financial professional or visit your financial intermediary's website for more information.

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Virtus Mutual Funds P.O. Box 534470 Pittsburgh, PA 15253-4470

8047	1-26