Summary Prospectus April 10, 2017, as supplemented May 8, 2017

Virtus Duff  & Phelps International Equity Fund

A: VIEAX C: VIECX I: VIIEX T: VIETX

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, statement of additional information (SAI), annual report and other information about the fund online at virtus.com/products/prospectuses.

You can also get this information at no cost by calling 800-243-1574 or by sending an e-mail to: virtus.investment.partners@virtus.com. 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 April 10, 2017, as supplemented May 8, 2017, are incorporated by reference into this Summary Prospectus.

Investment Objective

The fund has an investment objective of long-term capital appreciation.

Fees and Expenses

The tables below illustrate all fees and expenses that you may pay if you buy and hold shares of the fund. 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. You may qualify for sales charge discounts in Class T Shares if you invest at least $250,000 in the fund. More information on these and other discounts is available: (i) from your financial advisor or other financial intermediary; (ii) under “Sales Charges” on page 202 of the fund’s prospectus; (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;” and (iv) under “Alternative Purchase Arrangements” on page 107 of the fund’s statement of additional information.

Shareholder Fees (fees paid directly from your investment)

Class A

Class C

Class I

Class T

Maximum Sales Charge (load) Imposed on Purchases (as a percentage of offering price)

​

5.75

%

​

Non

e

​

Non

e

​

2.50

%

Maximum Deferred Sales Charge (load) (as a percentage of the lesser of purchase price or redemption proceeds)

​

Non

e

​

1.00

%(a)

​

Non

e

​

Non

e

Annual Fund Operating Expenses (expenses that you pay each year as a percentage of the value of your investment)	Class A			Class C			Class I			Class T
Management Fees	​	0.85	%	​	0.85	%	​	0.85	%	​	0.85	%
Distribution and Shareholder Servicing (12b-1) fees	​	0.25	%	​	1.00	%	​	Non	e	​	0.25	%
Other Expenses	​	1.93	%	​	1.93	%	​	1.93	%	​	1.93	%(b)
Total Annual Fund Operating Expenses	​	3.03	%	​	3.78	%	​	2.78	%	​	3.03	%
Less: Fee Waiver and/or Expense Reimbursement(c)	​	(1.53)	%	​	(1.53)	%	​	(1.53)	%	​	(1.53)	%
Total Annual Fund Operating Expenses After Expense Reimbursement(c)	​	1.50	%	​	2.25	%	​	1.25	%	​	1.50	%

(a)

The deferred sales charge is imposed on Class C Shares redeemed during the first year only.

(b)

Estimated for current fiscal year, as annualized.

(c)

The fund's investment adviser has contractually agreed to limit the fund's total operating expenses (excluding certain expenses, such as front-end or contingent deferred sales charges, taxes, interest, brokerage commissions, unusual or infrequently occurring expenses (such as litigation) and acquired fund fees and expenses, if any) so that such expenses do not exceed 1.50% for Class A Shares, 2.25% for Class C Shares, 1.25% for Class I Shares and 1.50% for Class T Shares through April 30, 2018. 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 under these arrangements for a period of three years following the time such reimbursement occurred.

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. 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 arrangement remains in place for the contractual period. Although your actual costs may be higher or lower, based on these assumptions your costs would be:

​	Share Status	1 Year		3 Years		5 Years		10 Years
Class A	Sold or Held	​	$719	​	$1,322	​	$1,949	​	$3,627
Class C	Sold	​	$328	​	$1,014	​	$1,820	​	$3,922
	Held	​	$228	​	$1,014	​	$1,820	​	$3,922
Class I	Sold or Held	​	$127	​	$717	​	$1,333	​	$2,998
Class T	Sold or Held	​	$399	​	$1,022	​	$1,671	​	$3,407

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 70% of the average value of its portfolio.

Investments, Risks and Performance

Principal Investment Strategies

Under normal circumstances, the fund invests at least 80% of its assets in equity securities of issuers located outside of the United States. The fund invests primarily in developed countries, but may also invest in issuers located in emerging market countries. The subadviser seeks to diversify its portfolio from a variety of sectors and countries, and typically invests in the securities of medium to large capitalization companies, but is not limited to investing in the securities of companies of any particular size. The fund may use derivatives to hedge against foreign currency exchange rates.

The fund seeks to provide investors with access to high-quality international businesses selling at attractive valuations. Ideally these companies are not only growing their earnings but are also creating economic value by maintaining or growing their return on invested capital. The subadviser’s process is driven by bottom-up fundamental research and informed by top-down macro views. In evaluating securities for inclusion in the fund, the subadviser applies a cash flow based approach to valuation, as well as additional fundamental research to assess the economic value added, financial strength, franchise quality, and management alignment of individual companies. Top-down macro research is utilized to assess the market environment, and to assist with regional, country, and sector allocations. As part of the macro process, the sub-adviser takes into account, among other things; monetary policy, political factors, economic growth, and valuation.

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 redemption by one or more large shareholders or groups of shareholders of their holdings in the fund could have an adverse impact on the remaining shareholders in the fund including by accelerating the realization of capital gains and increasing the fund's transaction costs. The principal risks of investing in the fund are:

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Depositary Receipts Risk.  The risk that investments in foreign companies through depositary receipts will expose the fund to the same risks as direct investments in securities of foreign issuers.

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Derivatives Risk.  The risk that the fund will incur a loss greater than the fund’s investment in, or will experience greater share price volatility as a result of investing in, a derivative contract. 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 to attempt to increase yield.

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Emerging Market Investing Risk.  The risk that prices of emerging markets securities will be more volatile, or will be more greatly affected by negative conditions, than those of their counterparts in more established foreign markets.

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Equity Securities Risk.  The risk that events negatively affecting issuers, industries or financial markets in which the fund invests will impact the value of the stocks held by the fund and, thus, the value of the fund’s shares over short or extended periods. Investments in a particular style or in small or medium-sized companies may enhance that risk.

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Foreign Investing Risk.  The risk that the prices of foreign securities in the fund’s portfolio will be more volatile than those of domestic securities, or will be negatively affected by currency fluctuations, less regulated or liquid securities markets, or economic, political or other developments.

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Market Volatility Risk.  The risk that the value of the securities in which the fund invests may go up or down in response to the prospects of individual issuers and/or general economic conditions. Such price changes may be temporary or may last for extended periods.

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Value Stocks Risk.  The risk that the fund will underperform when value investing is out of favor or that the fund’s investments will not appreciate in value as anticipated.

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.

Performance for Class T Shares is not shown here as Class T Shares were not available prior to the date of this prospectus.

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

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Calendar year total returns for Class I Shares

Returns do not reflect sales charges and would be lower if they did.

Best Quarter: Q1/2012: 7.53% Worst Quarter:​ Q3/2011: -13.50% Year to Date (3/31/17):​ 3.49%

Average Annual Total Returns (for the periods ended 12/31/16)

Returns reflect deduction of maximum sales charges and full redemption at end of periods shown.

​	1 Year			5 Years			Since Inception (9/16/10)
Class I	​	​	​	​	​	​	​	​	​
Return Before Taxes	​	-1.80	%	​	4.52	%	​	4.28	%
Return After Taxes on Distributions	​	-1.85	%	​	3.36	%	​	3.28	%
Return After Taxes on Distributions and Sale of Fund Shares	​	-0.55	%	​	3.48	%	​	3.40	%
Class A	​	​	​	​	​	​	​	​	​
Return Before Taxes	​	-7.73	%	​	3.06	%	​	3.11	%
Class C	​	​	​	​	​	​	​	​	​
Return Before Taxes	​	-2.83	%	​	3.48	%	​	3.24	%
MSCI EAFE® Index (net) (reflects no deduction for fees, expenses or taxes)	​	1.00	%	​	6.53	%	​	4.48	%

The MSCI EAFE® Index (net) is a free float-adjusted market capitalization-weighted index that measures developed foreign market equity performance, excluding the U.S. and Canada. The MSCI EAFE® Index (net) 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 Class I 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, Inc. (“VIA”).

The fund’s subadviser is Duff  & Phelps Investment Management Co. (“Duff  & Phelps”) (since September 2016), an affiliate of VIA.

Portfolio Management

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Frederick A. Brimberg,  Senior Managing Director and International Equity Portfolio Manager at Duff  & Phelps, is the manager of the fund. Mr. Brimberg has served as the Portfolio Manager of the fund since May 2013.

Purchase and Sale of Fund Shares

Minimum initial investments applicable to Class A, Class C and Class T 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, Class C and Class T Shares:

•

$100, generally

•

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

For Class I Shares, the minimum initial purchase is $100,000; there is no minimum for additional purchases.

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 advisor, broker-dealer or other financial intermediary.

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Virtus Mutual Funds
P.O. Box 9874
Providence, RI 02940-8074

8447 5-17​

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 advisor to recommend the fund over another investment. Ask your financial advisor or visit your financial intermediary’s Web site for more information.