Summary Prospectus by Investment Company (Form 497K)

SUMMARY PROSPECTUS - MAY 1, 2026

Guardian U.S. Government/Credit VIP Fund

This Summary Prospectus is intended for use in connection with variable annuity contracts and variable life insurance policies issued by The Guardian Insurance & Annuity Company, Inc. and is not intended for use by other investors. Before you invest, you may want to review the Fund's Statutory Prospectus, which contains more information about the Fund and its risks. You can find the Statutory Prospectus, reports to shareholders, and other information about the Fund, including the Fund's Statement of Additional Information (SAI), online at https://guardianvpt.onlineprospectus.net/GuardianVPT/Prospectuses/. You can also obtain this information at no cost by calling 1-888-GUARDIAN (1-888-482-7342) (variable life insurance policy owners); or by calling 1-800-830-4147 (variable annuity contract owners); variable life insurance policy owners may also send an email request to [email protected]. You may also contact your financial intermediary. This Summary Prospectus incorporates by reference the Fund's Prospectus and SAI, each dated May 1, 2026, as may be amended or supplemented from time to time.

Investment Objective

The Fund seeks total return with an emphasis on current income as well as capital appreciation.

Fees and Expenses of the Fund

This table shows the fees and expenses that you may pay if you buy, hold and sell shares of the Fund. The table does not reflect charges, fees or expenses that are, or may be, imposed under your variable annuity contract or variable life insurance policy through which Fund shares are offered as an investment option. If those charges, fees or expenses were reflected, the fees and expenses shown in the table would be higher. You may pay other fees, such as brokerage commissions and other fees to financial intermediaries, which are not reflected in the fee table or example below. For information about these charges, fees and expenses, please refer to the applicable contract or policy prospectus.

Annual Fund Operating Expenses

(expenses that you pay each year as a percentage of the value of your investment)

¹​ Park Avenue Institutional Advisers LLC, the Fund's investment manager (the "Manager"), has contractually agreed through April 30, 2027 to waive certain fees and/or reimburse certain expenses incurred by the Fund to the extent necessary to limit the Fund's Total Annual Fund Operating Expenses After Fee Waiver and/or Expense Reimbursement to 0.73% of the Fund's average daily net assets (excluding, if applicable, any acquired fund fees and expenses, taxes, interest, transaction costs and brokerage commissions, litigation and extraordinary expenses). The limitation may not be increased or terminated prior to this time without action by the Board of Trustees.

²​ "Fee Waiver and/or Expense Reimbursement" and "Total Annual Fund Operating Expenses After Fee Waiver and/or Expense Reimbursement" have been restated to reflect the current expense limitation arrangement.

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 and that the Fund's operating expenses remain the same. This Example does not reflect charges, fees or expenses that are, or may be, imposed under your variable annuity contract or variable life insurance policy, and would be higher if it did. The

Example reflects contractual fee waivers and/or expense reimbursements only for the duration of the current commitment, if applicable. Although your actual costs may be higher or lower, based on these assumptions your costs would be:

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. These costs, which are not reflected in the Annual Fund Operating Expenses or in the Example, affect the Fund's performance. As of the end of its most recent fiscal year, the Fund's portfolio turnover rate was 157% of the average value of its portfolio.

Principal Investment Strategies

Under normal circumstances, the Fund invests at least 80% of its net assets plus any borrowings for investment purposes in U.S. government securities and corporate credit investments. The Fund typically invests at least 50% of its net assets in U.S. government securities. The U.S. government securities in which the Fund invests include U.S. Treasury securities or other securities issued, guaranteed or otherwise backed by the U.S. government, its agencies, instrumentalities or government-sponsored enterprises, including bonds, notes, mortgage-backed securities and other fixed-income or debt instruments. These investments may also include securities issued by U.S. government agencies that are not backed by the full faith and credit of the U.S. government. In addition to mortgage-backed securities, the Fund may invest in other types of asset-backed securities, including commercial mortgage-backed securities ("CMBS"), collateralized mortgage obligations ("CMOs") and collateralized loan obligations ("CLOs"). The CLOs in which the Fund invests generally will be investment grade. The Fund may also invest in U.S. and foreign corporate debt securities, inflation-linked securities (e.g., Treasury Inflation-Protected Securities or "TIPS") and U.S. municipal securities. The corporate credit investments in which the Fund invests typically will be investment grade.

Under certain market conditions, the Fund may use futures contracts, options, swaps, and forward contracts to seek to (i) hedge various investments, (ii) manage or adjust duration and yield curve positioning, (iii) manage risk, (iv) enhance potential returns, or (v) as substitutes for permitted Fund investments. Duration is a measure of a bond price's sensitivity to changes in interest rates. Yield curve positioning represents the relationship between the interest rates of bonds having the same credit quality but different maturity dates.

Lord, Abbett & Co. LLC (the "Subadviser") seeks to manage the Fund's interest rate risk through the Subadviser's management of the average duration of the investments the Fund holds in its portfolio. The Fund as a whole expects to maintain an average duration of plus or minus one year of the duration of the U.S. government securities market, as measured by the Bloomberg US Intermediate Government/Credit Index (which was approximately 3.74 years as of March 31, 2026).

The Subadviser applies an active top-down and bottom-up analysis to construct the Fund's investment portfolio. The Subadviser uses a blend of fundamental research and quantitative tools to evaluate global economic conditions, opportunities, and risks across different segments of the fixed income market. The Subadviser selects specific investments for the Fund by considering a wide variety of factors, including yield, potential for appreciation in value, the credit quality of the issuer or collateral, maturity, and the degree of perceived risk associated with a specific investment relative to the potential for favorable investment returns and to other investments. The Subadviser may actively rotate the Fund's exposure to various fixed income asset classes based on its assessment of relative value.

The Fund's foreign investments may include debt securities issued by companies domiciled in emerging markets countries and companies whose principal business activities are located in emerging market countries. Emerging market countries are countries whose financial and capital markets are in the development phase and include countries located in Latin America, Asia, Africa, the Middle East, and developing countries of Europe, primarily Eastern Europe.

The Fund may sell a security when the Fund believes the security is less likely to benefit from the current market and economic environment, or shows signs of deteriorating fundamentals, among other reasons. The Fund may deviate from the investment strategy described above for temporary defensive purposes. The Fund may miss certain investment opportunities if defensive strategies are used and thus may not achieve its investment objective.

Principal Investment Risks

The risks summarized below are the principal risks of investing in the Fund. There is no guarantee that the Fund will achieve its investment objective and it is possible to lose money by investing in the Fund.

Market Risk. The financial and securities markets are very volatile and may be affected by political, regulatory, social, economic, and other global market developments and disruptions, including those arising out of geopolitical events, public health emergencies (such as the spread of infectious diseases, pandemics and epidemics), natural disasters, terrorism, and governmental or quasi-governmental actions. These events, or the threat or potential of one or more such events and developments, may negatively affect issuers, industries and markets worldwide and adversely affect the Fund and its investments. The market value of securities in which the Fund invests is based upon the market's perception of value and is not necessarily an objective measure of the securities' value. Changes to the market value of securities in which the Fund invests may be rapid and unpredictable. The price, value or liquidity of the Fund's investments may decline and will fluctuate, sometimes rapidly and unpredictably, in response to general market conditions (such as recessions, inflation, rapid interest rate changes, supply chain disruptions, tariffs and other restrictions on trade, such as sanctions) or other factors. Different sectors of the market, issuers, and security types may react differently to such developments. The fixed income investments in which the Fund invests may underperform other segments of the fixed income market or the fixed income market as a whole. Although prices of fixed income investments tend to rise and fall less dramatically than those of equity securities, they may experience heightened volatility and limited liquidity during certain market and economic conditions.

Issuer Risk. The Fund's investments may be adversely affected by a number of factors that directly relate to the issuer of securities held by the Fund, such as its earnings prospects and overall financial position. In addition, an issuer in which the Fund invests, or to which it has exposure, may perform poorly because of poor management decisions or other events, conditions, or factors, which could also negatively affect the Fund.

Active Management Risk. The Fund is actively managed by the Subadviser. The Fund may actively and frequently trade portfolio securities, which may lead to higher transaction costs that may negatively affect the Fund's performance. There is no guarantee that the Subadviser's investment techniques, risk analysis, and judgment implemented in making investment decisions for the Fund will be accurate or will produce the desired outcome. As a result, the Fund may be adversely affected and may underperform its benchmark index or funds with similar investment objectives.

U.S. Government Securities Risk. U.S. government securities may or may not be backed by the full faith and credit of the U.S. government and are subject to the risks associated with fixed-income instruments, particularly interest rate risk and credit risk. The Fund is subject to the risk that the U.S. government will not make timely payments on its debt or provide financial support to U.S. government agencies, instrumentalities or sponsored enterprises if those entities are not able to meet their financial obligations.

Credit Risk. The Fund may lose money if the issuer or guarantor of a fixed income or debt instrument is unable or unwilling, or is perceived as unable or unwilling, to pay interest or repay principal on time or otherwise to honor its obligations. A fixed income or debt instrument held by the Fund may be adversely affected by changes in, or the market's perception of, the financial strength (or credit rating) of its issuer or guarantor or the credit rating of the instrument. Credit ratings may decrease rapidly and may not be an accurate assessment of liquidity or credit risk. Actual or perceived changes in economic, social, health, financial or political conditions in general or that affect a particular type of instrument, issuer, guarantor or counterparty can reduce the ability of the party to meet its obligations, which can affect the credit quality, liquidity and/or value of an instrument. The value of an instrument also may decline for reasons that relate directly to the issuer, guarantor or counterparty, such as management performance, financial leverage and reduced demand for goods and services.

Interest Rate Risk. The value of the Fund's investments may decline because of a change in interest rates. The negative impact on fixed income and debt instruments from potential interest rate changes could be swift and significant, including falling market values, increased redemptions and reduced liquidity. The value of an instrument with a longer duration will be more sensitive to changes in interest rates than a similar instrument with a shorter duration. Very low or negative interest rates may magnify interest rate risk. Low interest rates (or negative interest rates) may magnify the risks associated with rising interest rates. There is the risk that the income generated by investments may not keep pace with inflation. Actions by governments and central banking authorities can result in increases or decreases in interest rates. Periods of higher inflation could cause such authorities to raise interest rates, which may adversely affect the Fund and its investments. The Fund may also be subject to heightened interest rate risk when the Federal Reserve raises interest rates. Duration is a measure of a bond price's sensitivity to a given change in interest rates. For example, the price of a bond with a duration of three years would be expected to fall approximately 3% if interest rates were to rise by one percentage point. In addition, the Fund is subject to the risk that the Fund's income will decline because of falling interest rates, including negative interest rates, if the Fund holds floating or variable rate debt securities or if an issuer fails to pay interest and principal in a timely manner. Other factors that may affect the value of debt securities include, but are not limited to, economic, political, public health, and other crises and responses by governments and companies to such crises.

Mortgage-Backed and Other Asset-Backed Securities Risk. Mortgage-backed and other asset-backed securities are subject to the risks associated with fixed income investments. The value of mortgage-backed and other asset-backed securities held by the Fund may be adversely affected by, among other things, changes or perceived changes in interest rates and may exhibit additional volatility during periods of rising interest rates as a result of extended duration. In addition, mortgage-backed and other asset-backed securities are subject to the risk that underlying obligations will be repaid sooner (known as "prepayment risk") or later (known as "extension risk") than expected because of changes in interest rates, either of which may result in lower than expected returns for the Fund. Because mortgage-backed securities are backed by mortgage loans, they also are subject to risks associated with the ownership of real estate and the real estate industry. CMBS may be less liquid and exhibit greater price volatility than other types of mortgage- or asset-backed securities. The mortgage-backed securities in which the Fund invests may include CMOs. CMOs are created by dividing the principal and interest payments collected on a pool of mortgages into several revenue streams (tranches) with different priority rights to portions of the underlying mortgage payments. CMOs are subject to the same risks as other mortgage-backed securities, including interest rate, prepayment and extension risk, but also present certain special risks. CMOs are subject to cash flow uncertainty and price volatility. CMOs may exhibit more or less price volatility and interest rate risk than other types of mortgage-related obligations, and under certain interest rate and payment scenarios, the Fund may fail to recoup fully its investment in certain of these securities.

Municipal Obligations Risk. Issuers, including governmental issuers, may be unable to pay their obligations as they come due. The values of municipal obligations that depend on a specific revenue source to fund their payment obligations may fluctuate as a result of changes in the cash flows generated by the revenue source or changes in the priority of the municipal obligation to receive the cash flows generated by the revenue source. In addition, changes in federal tax laws or the activity of an issuer may adversely affect the tax-exempt status of municipal obligations. Loss of tax-exempt status may result in a significant decline in the values of such municipal obligations. Such uncertainties could cause increased volatility in the municipal securities market and could negatively impact the Fund's net asset value.

Collateralized Loan Obligation Risk. Collateralized loan obligations ("CLOs") bear many of the same risks as other forms of asset-backed securities, including interest rate risk, credit risk and default risk. As they are backed by pools of loans, CLOs also bear similar risks to investing in loans directly. CLOs issue classes or "tranches" that vary in risk and yield. CLOs may experience substantial losses attributable to loan defaults. Losses caused by defaults on underlying assets are borne first by the holders of subordinate tranches. The Fund's investment in a CLO may decrease in market value when the CLO experiences loan defaults or credit impairment, the disappearance of a subordinate tranche, or market anticipation of defaults and investor aversion to CLO securities as a class. CLO managers are responsible for selecting, managing and replacing the underlying bank loans within a CLO. CLO managers may have limited operating histories and, may be subject to conflicts of interests, including managing the assets of other clients or other investment vehicles, or receiving fees that incentivize maximizing the yield, and indirectly the risk, of a CLO. Adverse developments with respect to a CLO manager may adversely impact the performance of the CLO securities in which the Fund invests.

Counterparty Risk. Certain investments or investment transactions are subject to the risk that the Fund's counterparty will become insolvent or otherwise be unwilling or unable to perform its obligations in a timely manner or at all. As a result, the Fund may be unable to recover its investment from the counterparty or may obtain a limited recovery, and/or recovery may be delayed, which may result in a loss to the Fund.

Derivatives Risk. Derivatives are instruments whose value depends on (or is derived from) the value of an underlying security, asset, or other benchmark. Derivatives (including short exposures through derivatives) pose risks in addition to and greater than those associated with investing directly in other investments, including potentially heightened liquidity and valuation risk, counterparty risk, market risk, operational risk and legal risk. In addition, certain derivatives result in leverage, which can result in losses substantially greater than the amount invested in the derivatives by the Fund.

Forwards and Futures Contracts Risk. Forwards and futures contracts are derivative contracts that obligate a purchaser to purchase, and a seller to sell, a specific amount of an asset (e.g., a currency or security) at a specified future date and price. In addition to the risks generally applicable to derivatives, these contracts are particularly subject to the risk of imperfect correlation between the change in market value of the asset underlying a contract or the asset held by the Fund being hedged and the price of the forward or futures contract, as well as losses caused by unanticipated market movements, which are potentially unlimited.

Inflation-Linked Investments Risk. Inflation-linked investments, including TIPS, tend to react to changes in real interest rates (i.e., nominal interest rates minus the expected impact of inflation) and the principal and interest payments on such investments are adjusted periodically based on the inflation rate. The price of an inflation-linked investment generally decreases when real interest rates rise and increases when real interest rates fall and may be more volatile than other

fixed-income instruments. During periods of deflation, the Fund may receive no income from such investments and the Fund's use of these investments may be unsuccessful. With respect to TIPS, the United States Treasury guarantees the repayment of the original bond principal upon maturity, as adjusted for inflation. For other inflation-lined investments that do not provide a similar guarantee, the adjusted principal value of the investment to be repaid at maturity is subject to credit risk.

Emerging Markets Risk. The risks associated with foreign investments are heightened for investments in emerging markets as emerging markets are considered to be less developed than developing countries. In particular, investments in emerging markets may present market, currency, liquidity, valuation, and other risks that are different from, or greater than, the risks of investing in developed foreign markets. The risks of investing emerging markets are elevated under adverse market conditions. Furthermore, investments in or exposure to emerging markets are generally subject to additional risks, including the risks associated with trading in smaller markets, lower volumes of trading, and being subject to lower levels of government regulation and less extensive and transparent accounting, auditing, recordkeeping, financial reporting and other requirements, sensitivity to adverse political, economic or social events affecting the region where an emerging market is located, and the potential expropriation or nationalization of foreign deposits or assets. Emerging markets may be especially volatile and securities transactions in emerging markets may be subject to delayed settlement.

Foreign Investment and Currency Risk. Foreign investments, or exposure to foreign markets, present greater risks than investing in securities of U.S. issuers. Foreign securities are particularly susceptible to liquidity and valuation risk and may be especially volatile. These investments are subject to additional risks, including: smaller markets; differing reporting, accounting, and auditing standards; nationalization, expropriation, or confiscatory taxation; foreign currency fluctuations, currency blockage, or replacement; potential for default on sovereign debt; and political changes or diplomatic developments, which may include the imposition of economic sanctions, tariffs, or other measures by the United States or other governments and supranational organizations. Economic sanctions may be, and have been, imposed against certain countries, organizations, companies, entities and/or individuals. Certain foreign markets may rely heavily on particular industries or foreign capital and are more vulnerable to diplomatic developments (including regional and global, military or other conflicts), the imposition of economic sanctions, changes in international trading patterns, trade barriers (including tariffs) and other protectionist or retaliatory measures. Economic sanctions and other similar governmental actions or developments could, among other things, adversely impact the value and liquidity of the Fund's foreign investments and the Fund's ability to invest in foreign investments and thus make the Fund's investments in such securities less liquid or illiquid. The Fund's foreign investments that are denominated in or provide exposure to a foreign currency may be negatively affected by a decline in the foreign currency's value relative to the U.S. dollar. The value of foreign currencies may fluctuate quickly and significantly and may make the return on an investment increase or decrease, unrelated to the quality or performance of the investment itself. Foreign investments may also be subject to risk of loss because of more or less foreign government regulation, less public information, and less stringent investor protections and disclosure standards.

Liquidity and Valuation Risk. Any of the Fund's investments may become illiquid or less liquid in response to overall economic conditions or adverse investor perceptions. As a result, it may be difficult to sell the Fund's investments at a favorable time or price or at all. To meet redemption requests or otherwise raise cash, the Fund may be forced to sell investments at a disadvantageous time and/or price. In addition, it may be difficult for the Fund to accurately value investments or purchase or sell investments within a reasonable time at the price at which it has been valued for purposes of the Fund's net asset value. Certain investments, including thinly-traded securities, are particularly susceptible to liquidity and valuation risk. The Fund's fixed-income instruments may experience reduced liquidity as a result of the lack of an active market or limited dealer market-making capacity. Liquidity risk may be magnified during periods of interest rate volatility, market turmoil or periods of significant shareholder redemptions.

Options Risk. An option is a derivative contract where, for a premium payment or fee, the purchaser of the option is given the right but not the obligation to buy (a call option) or sell (a put option) the underlying asset (or settle for cash an amount based on an underlying asset, rate or index) at a specified price (the exercise price) during a period of time or on a specified date or dates. In addition to the risks generally applicable to derivatives, the prices of options can be highly volatile and the Fund's use of options can lower total returns and may affect the Fund's portfolio turnover rate and the amount of brokerage commissions paid by the Fund.

Swaps Risk. Swap agreements are derivatives contracts where the parties agree to exchange the returns (or differentials in rates of return) earned or realized on particular predetermined investments or instruments. In addition to the risks generally applicable to derivatives, risks associated with swap agreements include adverse changes in the returns of the

underlying instruments, failure of the counterparties to perform under the agreement's terms and the possible lack of liquidity with respect to the agreements.

Portfolio Turnover Risk. To the extent the Fund engages in active trading, it may have high portfolio turnover. Frequent purchases and sales of portfolio investments may result in higher Fund expenses, such as higher brokerage fees or other transaction costs, which may negatively affect the Fund's performance.

Performance

The following information provides some indication of the risks of investing in the Fund by showing changes in the Fund's performance from year to year and by showing how the Fund's average annual returns for the 1 year, 5 year and since inception periods compare with those of a broad measure of market performance and an additional index. The Bloomberg US Aggregate Bond Index serves as the Fund's regulatory index and provides a broad measure of market performance. The Bloomberg US Intermediate Government/Credit Index is the Fund's additional index and was selected to align more closely with the Fund's investment strategy and portfolio holdings. The Fund's past performance is not necessarily an indication of how the Fund will perform in the future. Updated performance information is available at www.guardianlife.com or by calling the phone number on the back of the Prospectus. Variable annuity contract or variable life insurance policy fees, expenses and charges are not reflected in the returns shown in the bar chart and table below. If they were, returns would be less than those shown.

The Fund engaged the Subadviser and modified its principal investment strategies as of March 3, 2025. The past performance shown in the bar chart and table below prior to that date reflects the performance of the Fund's prior manager and principal investment strategies.

Annual Returns (by calendar year)

Highest Quarterly Return: 5.04% (4th Q 2023)
Lowest Quarterly Return: -4.19% (1st Q 2022)

Average Annual Total Returns (for the periods ended December 31, 2025)

Management

Park Avenue Institutional Advisers LLC serves as the Fund's manager. Lord, and Abbett & Co. LLC serves as the Fund's subadviser. The following persons are jointly and primarily responsible for the day-to-day management of the Fund:

Purchase and Sale of Fund Shares

The Fund offers its shares only as underlying investment options to variable annuity contracts or variable life insurance policies issued by The Guardian Insurance & Annuity Company, Inc. ("GIAC"). You choose investment options through your contract or policy. You do not purchase Fund shares directly from, or redeem Fund shares directly with, the Fund. Please refer to your contract or policy prospectus for more information regarding the purchase and sale of Fund shares.

Tax Information

No tax information is provided because the Fund's shareholders are separate accounts of GIAC. For information concerning the tax consequences applicable to your variable annuity contract or variable life insurance policy, please refer to your contract or policy prospectus or consult with your tax advisor.

Financial Intermediary Compensation

If you purchase your variable annuity contract or variable life insurance policy through a broker-dealer or other financial intermediary, GIAC, the Fund or their affiliates may pay the intermediary for the sale of the contract or policy, the selection of the Fund and certain related services. These payments may create a conflict of interest by influencing the intermediary and your salesperson to recommend the contract or policy over another investment or annuity or insurance product, or to recommend the Fund over another investment option available under the contract or policy. Ask your salesperson or visit your financial intermediary's website for more information.

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