Calamos Short-Term Bond Fund (CSTIX)

An investment in the Fund(s) is subject to risks, and you could lose money on your investment in the Fund(s). There can be no assurance that the Fund(s) will achieve its investment objective. Your investment in the Fund(s) is not a deposit in a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation (FDIC) or any other government agency. The risks associated with an investment in the Fund(s) can increase during times of significant market volatility. The Fund(s) also has specific principal risks, which are described below. More detailed information regarding these risks can be found in the Fund's prospectus.

The principal risks of investing in the Calamos Short-Term Bond Fund include: interest rate risk consisting of loss of value for income securities as interest rates rise, credit risk consisting of the risk of the borrower to miss payments, high yield risk, liquidity risk, mortgage-related and other asset-back securities risk, including extension risk and prepayment risk, U.S. Government security risk, foreign securities risk, non-U.S. Government obligation risk and portfolio selection risk. As a result of political or economic instability in foreign countries, there can be special risks associated with investing in foreign securities, including fluctuations in currency exchange rates, increased price volatility and difficulty obtaining information. In addition, emerging markets may present additional risk due to potential for greater economic and political instability in less developed countries.

Performance data quoted represents past performance, which is no guarantee of future results. Current performance may be lower or higher than the performance quoted. Please refer to Important Risk Information. The principal value and return of an investment will fluctuate so that your shares, when redeemed, may be worth more or less than their original cost. Performance reflected at NAV does not include the Fund's maximum front-end sales load of 2.25%. Had it been included, the Fund's return would have been lower.

The Bloomberg Barclays U.S. Government/Credit 1-3 Years Index includes all medium and larger issues of U.S. government, investment-grade corporate, and investmentgrade international dollar-denominated bonds that have maturities of between 1 and 3 years and are publicly issued.

Unmanaged index returns assume reinvestment of any and all distributions and, unlike fund returns, do not reflect fees, expenses or sales charges. Investors cannot invest directly in an index.

Average annual total return measures net investment income and capital gain or loss from portfolio investments as an annualized average. All performance shown assumes reinvestment of dividends and capital gains distributions.

The funds' gross expense ratios as of the prospectus dated 3/1/2019 are as follows: A Shares 0.95% and I Shares 0.70%.

NOT FDIC INSURED | NO BANK GUARANTEE | MAY LOSE VALUE

An investment in the Fund(s) is subject to risks, and you could lose money on your investment in the Fund(s). There can be no assurance that the Fund(s) will achieve its investment objective. Your investment in the Fund(s) is not a deposit in a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation (FDIC) or any other government agency. The risks associated with an investment in the Fund(s) can increase during times of significant market volatility. The Fund(s) also has specific principal risks, which are described below. More detailed information regarding these risks can be found in the Fund's prospectus.

The principal risks of investing in the Calamos Short-Term Bond Fund include: interest rate risk consisting of loss of value for income securities as interest rates rise, credit risk consisting of the risk of the borrower to miss payments, high yield risk, liquidity risk, mortgage-related and other asset-back securities risk, including extension risk and prepayment risk, U.S. Government security risk, foreign securities risk, non-U.S. Government obligation risk and portfolio selection risk. As a result of political or economic instability in foreign countries, there can be special risks associated with investing in foreign securities, including fluctuations in currency exchange rates, increased price volatility and difficulty obtaining information. In addition, emerging markets may present additional risk due to potential for greater economic and political instability in less developed countries.

Holdings and weightings are subject to change daily. Holdings are provided for informational purposes only and should not be deemed as a recommendation to buy or sell the securities mentioned.

Bond Credit Quality allocation reflects the higher of the ratings of Standards & Poor's Corporation; Moody's Investors Service, Inc. Ratings are relative, subjective and not absolute standards of quality, represent the opinions of the independent, Nationally Recognized Statistical Rating Organizations (NRSRO), and are adjusted to the Standards & Poor's scale shown. Ratings are measured using a scale that typically ranges from AAA (highest) to D (lowest). The security's credit rating does not eliminate risk. The table excludes equity securities, cash and cash equivalents. For more information about securities ratings, please see the Fund's Statement of Additional Information at calamos.com. Additional information on ratings methodologies are available by visiting the NRSRO websites: www.standardandpoors.com and www.moodys.com.

Duration- provides a measure of the Fund's interest rate sensitivity-the longer a fund's duration, the more sensitive it is to shifts in interest rates

Option adjusted spread is the yield spread which has to be added to a benchmark yield curve to discount a security's payments to match its market price; uses a dynamic pricing model that accounts for embedded options and is usually measured in basis points.

Turnover-Is the percentage of assets in a portfolio that changed over a certain period, often a year; higher turnover indicates greater buying and selling activity.

Yield-to-worst is the lowest potential yield that can be received on a bond without the issuer defaulting.

The Bloomberg Barclays U.S. Government/Credit 1-3 Years Index includes all medium and larger issues of U.S. government, investment-grade corporate, and investmentgrade international dollar-denominated bonds that have maturities of between 1 and 3 years and are publicly issued.

NOT FDIC INSURED | NO BANK GUARANTEE | MAY LOSE VALUE

An investment in the Fund(s) is subject to risks, and you could lose money on your investment in the Fund(s). There can be no assurance that the Fund(s) will achieve its investment objective. Your investment in the Fund(s) is not a deposit in a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation (FDIC) or any other government agency. The risks associated with an investment in the Fund(s) can increase during times of significant market volatility. The Fund(s) also has specific principal risks, which are described below. More detailed information regarding these risks can be found in the Fund's prospectus.

The principal risks of investing in the Calamos Short-Term Bond Fund include: interest rate risk consisting of loss of value for income securities as interest rates rise, credit risk consisting of the risk of the borrower to miss payments, high yield risk, liquidity risk, mortgage-related and other asset-back securities risk, including extension risk and prepayment risk, U.S. Government security risk, foreign securities risk, non-U.S. Government obligation risk and portfolio selection risk. As a result of political or economic instability in foreign countries, there can be special risks associated with investing in foreign securities, including fluctuations in currency exchange rates, increased price volatility and difficulty obtaining information. In addition, emerging markets may present additional risk due to potential for greater economic and political instability in less developed countries.

Performance data quoted represents past performance, which is no guarantee of future results. Current performance may be lower or higher than the performance quoted. Please refer to Important Risk Information. The principal value and return of an investment will fluctuate so that your shares, when redeemed, may be worth more or less than their original cost. Performance reflected at NAV does not include the Fund's maximum front-end sales load of 2.25%. Had it been included, the Fund's return would have been lower.

The funds' gross expense ratios as of the prospectus dated 3/1/2019 are as follows: A Shares 0.95% and I Shares 0.70%.

NOT FDIC INSURED | NO BANK GUARANTEE | MAY LOSE VALUE

An investment in the Fund(s) is subject to risks, and you could lose money on your investment in the Fund(s). There can be no assurance that the Fund(s) will achieve its investment objective. Your investment in the Fund(s) is not a deposit in a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation (FDIC) or any other government agency. The risks associated with an investment in the Fund(s) can increase during times of significant market volatility. The Fund(s) also has specific principal risks, which are described below. More detailed information regarding these risks can be found in the Fund's prospectus.

The principal risks of investing in the Calamos Short-Term Bond Fund include: interest rate risk consisting of loss of value for income securities as interest rates rise, credit risk consisting of the risk of the borrower to miss payments, high yield risk, liquidity risk, mortgage-related and other asset-back securities risk, including extension risk and prepayment risk, U.S. Government security risk, foreign securities risk, non-U.S. Government obligation risk and portfolio selection risk. As a result of political or economic instability in foreign countries, there can be special risks associated with investing in foreign securities, including fluctuations in currency exchange rates, increased price volatility and difficulty obtaining information. In addition, emerging markets may present additional risk due to potential for greater economic and political instability in less developed countries.

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The Fund's investment advisor has contractually agreed to reimburse Fund expenses through March 1, 2022 to the extent necessary so that Total Annual Fund Operating Expenses (excluding taxes, interest, short interest, short dividend expenses, brokerage commissions, acquired fund fees and expenses, and extraordinary expenses, if any) of Class A and Class I are limited to 0.65% and 0.40% of average net assets, respectively. Calamos Advisors may recapture previously waived expense amounts within the same fiscal year for any day where the respective Fund's expense ratio falls below the contractual expense limit up to the expense limit for that day. This undertaking is binding on Calamos Advisors and any of its successors and assigns. This agreement is not terminable by either party.

NOT FDIC INSURED | NO BANK GUARANTEE | MAY LOSE VALUE