January 27, 2023 as supplemented February 7, 2023

Summary Prospectus

Calamos Antetokounmpo Global Sustainable Equities ETF

(NYSE Arca – SROI)

Before you invest, you may want to review the Fund's prospectus and statement of additional information, which contain more information about the Fund and its risks. You can find the Fund's prospectus, statement of additional information, reports to shareholders and other information about the Fund online at www.calamos.com/sroi. You can also get this information at no cost by calling 866.363.9219 or by sending an e-mail request to prospectus@calamos.com. The current prospectus and statement of additional information, both dated January 27, 2023 (and as each may be amended or supplemented), are incorporated by reference into this summary prospectus.

•  Calamos Antetokounmpo Asset Management LLC ("CGAM") serves as the adviser ("Adviser") to the Calamos Antetokounmpo Global Sustainable Equities ETF (the "Fund"). CGAM is jointly owned by Calamos Advisors LLC and Original C Fund, LLC, an entity whose voting rights are wholly owned by Original PE, LLC which, in turn, is wholly owned by Giannis Sina Ugo Antetokounmpo.

•  Mr. Antetokounmpo serves on the Adviser's Board of Directors and has indirect control of half of the Adviser's Board.

•  Mr. Antetokounmpo is not a portfolio manager of the Fund and will not be involved in the day-to-day management of the Fund's investments, and neither Original C nor Mr. Antetokounmpo shall provide any "investment advice" to the Fund. Mr. Antetokounmpo provided input in selecting the initial strategy for the Fund.

•  Mr. Antetokounmpo will be involved with marketing efforts on behalf of the Adviser.

•  If Mr. Antetokounmpo is no longer involved with the Fund or the Adviser then "Antetokounmpo" will be removed from the name of the Fund and the Adviser. Further, shareholders would be notified of any change in the name of the Fund or its strategy.

Investment Objective

Calamos Antetokounmpo Global Sustainable Equities ETF (the "Fund") seeks long-term capital appreciation.

Fees and Expenses of the Fund

The following table describes the fees and expenses that you may pay if you buy, hold and sell shares of the Fund ("Fund Shares"). Investors may pay other fees, such as brokerage commissions and other fees to financial intermediaries, which are not reflected in the tables and examples below.

Annual Fund Operating Expenses (ongoing expenses that you pay each year as a percentage of the value of your investments)

Management Fees	0.95	%
Distribution and/or Service Fees (12b-1)	0.00	%
Other Expenses1	0.00	%
Total Annual Fund Operating Expenses	0.95	%

1  Other Expenses is an estimate based on the expenses the Fund expects to incur for the current fiscal year.

Example

This example is intended to help you compare the cost of investing in the Fund with the cost of investing in other funds. The example assumes that you invest $10,000 in the Fund for the time periods indicated, and then sell all of your Fund Shares at the end of those periods. The example also assumes that your investment has a 5% return each year and that the Fund's operating expenses remain the same. Although your actual costs may be higher or lower, based on these assumptions your costs, whether you sell or hold your Fund Shares, would be:

Year 1		Year 3
	97		303

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. Because the Fund has not yet commenced operations, portfolio turnover information is unavailable at this time.

Calamos Antetokounmpo Global Sustainable Equities ETF

Principal Investment Strategies

The Fund is an actively managed exchange-traded fund ("ETF") that does not seek to replicate the performance of a specified index. The Fund will, under normal circumstances, invest at least 80% of its net assets (plus borrowings for investment purposes, if any) in equity securities of companies in developed markets (including the U.S.) and emerging markets (including frontier market countries) that, in the view of Calamos Advisors LLC ("Calamos Advisors" or the "Sub-adviser"), have above average growth potential and meet the environmental, social and governance ("ESG") criteria set out below. The Fund will maintain a minimum investment in non-U.S. equity securities, including emerging markets that will be no less than 40% of the Fund's net assets under normal market conditions. The Fund will generally be invested in a minimum of five (5) countries.

Emerging markets are markets of countries in the initial stages of industrialization and generally have low per capita income. Foreign (non-U.S.) companies are those that either maintain their principal place of business outside of the United States, have their securities principally traded on non-U.S. exchanges or were formed under the laws of non-U.S. countries. Foreign companies may include companies doing business in the United States but meet the general criteria of a foreign company described above. Certain emerging markets are sometimes referred to as "frontier markets." Frontier markets are the least advanced capital markets in the developing world. Frontier markets are countries with investable stock markets that are less established than those in the emerging markets. To determine if a country is an emerging market or frontier market country, Calamos Advisors will use the classification provided by MSCI, Inc, a global investment research firm that provides stock indexes and portfolio risk and performance analytics. Foreign securities include American Depositary Receipts ("ADRs") or securities guaranteed by a U.S. person but which represent underlying shares of foreign issuers, and may include foreign securities in the form of European Depositary Receipts ("EDRs"), Global Depositary Receipts ("GDRs") or other securities representing underlying shares of foreign issuers.

Calamos Advisers ("the team") utilizes a proprietary ESG rating system, considering both quantitative and qualitative factors, to identify responsible, engaged companies (companies that demonstrate awareness and action surrounding the material ESG issues facing their businesses and industries). The team believes that a company's understanding of ESG principles demonstrates the qualities of innovation and leadership that create a distinct competitive advantage and build long-term value for a company. Calamos Advisors considers a company's position on various factors such as ecological limits, environmental stewardship, environmental strategies, stance on human rights and equality, societal impact as well as its corporate governance practices. The team conducts fundamental research to find companies with attractive ESG and financial attributes. In conducting fundamental research, Calamos Advisors combines traditional investment information with its proprietary three-pronged ESG process to identify investments which it believes promote certain environmental and/or social characteristics. Calamos Advisors believes that this creates a complete picture of how each company behaves commercially and how it deals with existing and emerging ESG risks and opportunities. The three-pronged ESG process consists of: 1) exclusionary screens; 2) materiality assessments and 3) environmental and social impact scoring.

Calamos Advisors utilizes a range of data sources as part of its proprietary ESG ratings system. These data sources may include: corporate disclosures, third party research providers (e.g., ISS ESG, MSCI ESG, Bloomberg, etc.), non-governmental organizations ("NGOs") and non-profits (e.g., Greenpeace, Friends of Earth, etc.), academic publications, news services and memberships. While the team may utilize the underlying data which supports a third party's ESG rating of an issuer, the team does not rely on any ESG ratings of third-party research providers. Calamos Advisors employs its proprietary ESG ratings system for both initial company recommendations and ongoing monitoring of investments.

Calamos Advisors may sell an investment in cases of valuation adjustments, availability of more attractive alternatives, or breakdowns in financial fundamentals or ESG performance.

The Fund is classified as "diversified" under the Investment Company Act of 1940 (the "1940 Act").

Principal Risks

An investment in the Fund is subject to risks, and you could lose money on your investment in the Fund. There can be no assurance that the Fund will achieve its investment objective. You should not consider investing in the Fund if your investment objective differs from the Funds' investment objective of long-term capital appreciation or if you are not willing to accept the principal risks associated with an investment in the Fund. The risks associated with an investment in the Fund can increase during times of significant market volatility. Your investment in the Fund is not a deposit in a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency. The principal risks are presented in order of importance, with the most significant risks appearing first. Each risk summarized below is considered a "principal risk" of investing in the Fund, regardless of the order in which it appears. The principal risks of investing in the Fund include:

•  Equity Securities Risk — The securities markets are volatile, and the market prices of the Fund's securities may decline generally. The price of equity securities fluctuates based on changes in a company's financial condition and overall market and economic conditions. If the market prices of the securities owned by the Fund fall, the value of your investment in the Fund will decline.

•  Portfolio Selection Risk — The value of your investment may decrease if the judgment of Calamos Advisors about the attractiveness, value or market trends affecting a particular security, issuer, industry or sector or about market movements is incorrect.

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Calamos Antetokounmpo Global Sustainable Equities ETF

•  Key-Person Dependence Risk — The Adviser is jointly owned and controlled by Calamos Advisors LLC and, indirectly, by Giannis Sina Ugo Antetokounmpo, a well-known professional athlete. Unanticipated events, including, without limitation, death, adverse reputational events or business disputes, could result in Mr. Antetokounmpo no longer being associated or involved with the Adviser. Any such event could adversely impact the Fund and result in shareholders experiencing substantial losses.

•  Large-Capitalization Investing Risk — Large-capitalization stocks as a group could fall out of favor with the market, which may cause the Fund to underperform funds that focus on other types of stocks.

•  American Depositary Receipts Risk — The stocks of most foreign companies that trade in the U.S. markets are traded as ADRs. U.S. depositary banks issue these stocks. Each ADR represents one or more shares of foreign stock or a fraction of a share. The price of an ADR corresponds to the price of the foreign stock in its home market, adjusted to the ratio of the ADRs to foreign company shares. Therefore, while purchasing a security on a U.S. exchange, the risks inherently associated with foreign investing still apply to ADRs.

•  Portfolio Turnover Risk — The portfolio managers may actively and frequently trade securities or other instruments in the Fund's portfolio to carry out its investment strategies. A high portfolio turnover rate increases transaction costs, which may increase the Fund's expenses. Frequent and active trading may also cause adverse tax consequences for investors in the Fund due to an increase in short-term capital gains.

•  Sector Risk — To the extent the Fund invests a significant portion of its assets in a particular sector, a greater portion of the Fund's performance may be affected by the general business and economic conditions affecting that sector. Each sector may share economic risk with the broader market, however there may be economic risks specific to each sector. As a result, returns from those sectors may trail returns from the overall stock market, and it is possible that the Fund may underperform the broader market or experience greater volatility.

•  Small and Mid-Sized Company Risk — Small and mid-sized company stocks have historically been subject to greater investment risk than large company stocks. The prices of small and mid-sized company stocks tend to be more volatile than prices of large company stocks.

•  Sustainability (ESG) Policy Risk — The Fund's ESG policy could cause it to perform differently compared to similar funds that do not have such a policy. The application of the social and environmental standards of Calamos Advisors may affect the Fund's exposure to certain issuers, industries, sectors, and factors that may impact the relative financial performance of the Fund — positively or negatively — depending on whether such investments are in or out of favor. In executing the Fund's investment strategy Calamos Advisors has developed a proprietary ESG rating system that relies in part on ESG related data provided by third parties. There is no assurance that third-party ESG data sources will always be available or that such data will be accurate.

•  Foreign Securities Risk — Risks associated with investing in foreign securities include fluctuations in the exchange rates of foreign currencies that may affect the U.S. dollar value of a security, the possibility of substantial price volatility as a result of political and economic instability in the foreign country, less public information about issuers of securities, different securities regulation, different accounting, auditing and financial reporting standards and less liquidity than in U.S. markets.

•  Emerging Markets Risk — Emerging market countries may have relatively unstable governments and economies based on only a few industries, which may cause greater instability. The value of emerging market securities will likely be particularly sensitive to changes in the economies of such countries. These countries are also more likely to experience higher levels of inflation, deflation or currency devaluations, which could hurt their economies and securities markets. Certain emerging markets are sometimes referred to as "frontier markets." Frontier markets, the least advanced capital markets in the developing world, are among the riskiest markets in the world in which to invest. Investments in this sector are typically illiquid, nontransparent and subject to very low regulation levels as well as high transaction fees, and may also have substantial political and currency risk.

•  Authorized Participant Concentration Risk — Only an Authorized Participant may engage in creation or redemption transactions directly with the Fund, and none of those Authorized Participants is obligated to engage in creation and/or redemption transactions. The Fund has a limited number of institutions that may act as Authorized Participants on an agency basis (i.e., on behalf of other market participants). To the extent that Authorized Participants exit the business or are unable to proceed with creation or redemption orders with respect to the Fund and no other Authorized Participant is able to step forward to create or redeem, Fund Shares may be more likely to trade at a premium or discount to NAV and possibly face trading halts or delisting. Authorized Participant concentration risk may be heightened for ETFs, such as the Fund, that invest in securities issued by non-U.S. issuers or other securities or instruments that have lower trading volumes.

•  New Fund Risk — The Fund is a recently organized investment company with a limited operating history. As a result, prospective investors have a limited track record or history on which to base their investment decision.

•  Costs of Buying and Selling Fund Shares — Due to the costs of buying or selling Fund Shares, including brokerage commissions imposed by brokers and bid/ask spreads, frequent trading of Fund Shares may significantly reduce investment results and an investment in Fund Shares may not be advisable for investors who anticipate regularly making small investments.

•  Currency Risk — To the extent that the Fund invests in securities or other instruments denominated in or indexed to foreign currencies, changes in currency exchange rates bring an added dimension of risk. Currency fluctuations could negatively impact investment gains or add to investment losses. Although the Fund may attempt to hedge against currency risk, the hedging instruments may not always perform

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Calamos Antetokounmpo Global Sustainable Equities ETF

as the Fund expects and could produce losses. Suitable hedging instruments may not be available for currencies of emerging market countries. Calamos Advisors may determine not to hedge currency risks, even if suitable instruments appear to be available.

•  Market Maker Risk — If the Fund has lower average daily trading volumes, it may rely on a small number of third-party market makers to provide a market for the purchase and sale of Fund Shares. Any trading halt or other problem relating to the trading activity of these market makers could result in a dramatic change in the spread between the Fund's net asset value and the price at which the Fund Shares are trading on the Exchange, which could result in a decrease in value of the Fund Shares. In addition, decisions by market makers or authorized participants to reduce their role or step away from these activities in times of market stress could inhibit the effectiveness of the arbitrage process in maintaining the relationship between the underlying values of the Fund's portfolio securities and the Fund's market price. This reduced effectiveness could result in Fund Shares trading at a discount to net asset value and also in greater than normal intra-day bid-ask spreads for Fund Shares.

•  National Closed Market Trading Risk — To the extent that the underlying securities and/or other assets held by the Fund trade on non-U.S. exchanges or in non-U.S. markets that may be closed when the securities exchange on which Fund Shares trade is open, there are likely to be deviations between the current price of such an underlying security and the last quoted price for the underlying security (i.e., the Fund's quote from the closed non-U.S. market). The impact of a closed foreign market on the Fund is likely to be greater where a large portion of the Fund's underlying securities and/or other assets trade on that closed non-U.S. market or when the non-U.S. market is closed for unscheduled reasons. These deviations could result in premiums or discounts to the Fund's NAV that may be greater than those experienced by other ETFs.

•  Premium-Discount Risk — Fund Shares may trade above or below their net asset value ("NAV"). The market prices of Fund Shares will generally fluctuate in accordance with changes in NAV as well as the relative supply of, and demand for, Fund Shares on the Exchange. The trading price of Fund Shares may deviate significantly from NAV during periods of market volatility.

•  Secondary Market Trading Risk — Investors buying or selling Fund Shares in the secondary market will pay brokerage commissions or other charges imposed by brokers as determined by that broker. Brokerage commissions are often a fixed amount and may be a significant proportional cost for investors seeking to buy or sell relatively small amounts of Fund Shares. Although the Fund Shares are listed on the Exchange, there can be no assurance that an active or liquid trading market for them will develop or be maintained. In addition, trading in Fund Shares on the Exchange may be halted.

•  Trading Issues Risk — Trading in Fund shares on the Exchange may be halted due to market conditions or for reasons that, in the view of the Exchange, make trading in shares inadvisable. In addition, trading in Fund shares on the Exchange is subject to trading halts caused by extraordinary market volatility pursuant to the Exchange's "circuit breaker" rules. There can be no assurance that the requirements of the Exchange necessary to maintain the listing of the Fund will continue to be met or will remain unchanged. The Fund may have difficulty maintaining its listing on the Exchange in the event the Fund's assets are small, the Fund does not have enough shareholders, or if the Fund is unable to proceed with creation and/or redemption orders.

Fund Performance

The Fund had not commenced operations as of the date of this prospectus. Accordingly, performance data is not included. When performance data becomes available, it will be posted to the following website: www.calamos.com. Past performance (before and after taxes) is not an indication of future performance.

Investment Adviser

Calamos Antetokounmpo Asset Management LLC, doing business as CGAM ("CGAM" or the "Adviser")

Subadviser

Calamos Advisors LLC

Portfolio Managers

PORTFOLIO MANAGER/FUND TITLE (IF APPLICABLE)	PORTFOLIO MANAGER EXPERIENCE IN THE FUND	PRIMARY TITLE WITH SUB-ADVISER
James Madden	since Fund's inception	SVP, Co-Portfolio Manager
Anthony Tursich	since Fund's inception	SVP, Co-Portfolio Manager
Beth Williamson	since Fund's inception	VP, Associate Portfolio Manager

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Calamos Antetokounmpo Global Sustainable Equities ETF

Other Important Information Regarding Fund Shares

Portfolio Holdings. The Fund's portfolio holdings are disclosed on its website daily after the close of trading on the Exchange and prior to the opening of trading on the Exchange the following day. A description of the Fund's policies and procedures with respect to the disclosure of the Fund's portfolio holdings is available in the Fund's Statement of Additional Information ("SAI").

Premium/Discount Information. Information about the premiums and discounts at which the Fund's Shares have traded will be available at www.calamos.com.

Purchase and Sale of Fund Shares

The Fund will issue (or redeem) Fund Shares to certain institutional investors (typically market makers or other broker-dealers) only in large blocks of Fund Shares known as "Creation Units." Creation Unit transactions are conducted in exchange for the deposit or delivery of a designated portfolio of in-kind securities and/or cash.

Individual Fund Shares may only be purchased and sold on the Exchange, other national securities exchanges, electronic crossing networks and other alternative trading systems through your broker-dealer at market prices. Because Fund Shares trade at market prices rather than at net asset value ("NAV"), Fund Shares may trade at a price greater than NAV (premium) or less than NAV (discount). When buying or selling Fund Shares in the secondary market, you may incur costs attributable to the difference between the highest price a buyer is willing to pay to purchase Fund Shares (bid) and the lowest price a seller is willing to accept for Fund Shares (ask) (the "bid-ask spread"). Recent information regarding the Fund's NAV, market price, premiums and discounts, and bid-ask spreads is available at https://www.calamos.com/.

Tax Information

Income and capital gains distributions you receive from the Fund generally are subject to federal income taxes and may also be subject to state and local taxes. The Fund intends to distribute income, if any, quarterly, and capital gains, if any, at least annually.

Payments to Broker-Dealers and Other Financial Intermediaries

If you purchase shares of 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 salesperson to recommend the Fund over another investment. Ask your salesperson or visit your financial intermediary's website for more information.

2020 Calamos Court
Naperville, IL 60563-2787
866.363.9219
www.calamos.com
811-22887

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