Summary Prospectus by Investment Company (Form 497K)

SUMMARY PROSPECTUS - MAY 1, 2026

Guardian Strategic Large Cap Core 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 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 0.91% 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 43% of the average value of its portfolio.

Principal Investment Strategies

AllianceBernstein L.P., the Fund's subadviser (the "Subadviser"), seeks to achieve the Fund's objective by investing, under normal circumstances, at least 80% of its net assets plus any borrowings for investment purposes (measured at the time of investment) in common stocks, or other investments that the Subadviser believes have similar economic characteristics, of companies with large market capitalizations. The Subadviser defines large capitalization companies as companies with market capitalizations similar to companies in the Standard & Poor's 500® Index (the "Index") at the time of purchase. Although expected to change frequently, the market capitalization range of the Index was approximately $6.64 billion to $4.24 trillion as of March 31, 2026.

The Fund invests in companies that are determined by the Subadviser to offer favorable long-term sustainable profitability, price stability, and attractive valuations. The Subadviser selects investments based on an integrated approach that combines both fundamental and quantitative research to identify attractive investment opportunities. Factors that the Subadviser considers include: a company's record and projections of profitability, accuracy and availability of information with respect to the company, success and experience of management, competitive advantage, low stock price volatility, and liquidity of the company's securities. The Subadviser compares these results to the characteristics of the general stock markets to determine the relative attractiveness of each company at a given time. The Subadviser weighs economic, political and market factors in making investment decisions. The Subadviser seeks to manage the Fund's portfolio so that it is subject to less share price volatility than many other U.S. mutual funds, although there can be no guarantee that the Subadviser will be successful in this regard.

The Subadviser expects that normally the Fund's portfolio will primarily invest in securities issued by U.S. companies, although it may, at times, also invest in foreign securities. The Fund may, at times, invest in shares of exchange-traded funds ("ETFs") in lieu of making direct investments in securities or to seek to obtain desired exposures.

The Fund may enter into derivatives transactions, such as options, futures contracts, forwards and swaps. The Fund may use options strategies involving the purchase and/or writing of combinations of call and/or put options, including on individual securities and stock indices, futures contracts (including futures contracts on individual securities and stock indices) or shares of ETFs. Derivatives transactions may be used, for example, in an effort to earn extra income, to attempt to adjust exposure to individual securities or markets, or to seek to protect all, or a portion, of the Fund's portfolio from a decline in value, sometimes within certain ranges.

The Subadviser typically may sell investments when it believes that they no longer offer attractive future returns compared with other investment opportunities or that they present undesirable risks or in an attempt to limit losses on investments that may decline or have declined in value.

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.

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.

Equity Securities Risk. The price or value of the Fund's investments in a company's equity securities, such as common or preferred stock, may rise or fall rapidly or unpredictably and are subject to real or perceived changes in the company's financial condition and overall market and economic conditions. Equity securities are normally more volatile than fixed-income investments. Common stocks generally represent the riskiest investment in a company and preferred stocks generally rank junior to a company's debt with respect to dividends, which the company may or may not declare.

Large-Capitalization Company Risk. Large-capitalization companies may be unable to attain the same growth rate of small- or mid-capitalization companies. In addition, large-capitalization companies may be unable to respond to competitive challenges or opportunities as quickly as smaller companies.

Growth Investment Style Risk. Different investment styles tend to perform differently and shift in and out of favor depending on changes in market and economic sentiment and conditions. Securities of "growth" companies may be more volatile than other stocks and may involve special risks. If the Subadviser's perception of a company's growth potential is not realized, the securities purchased may not perform as expected and may be out of favor for an extended period of time, reducing the Fund's returns. Thus, the Fund may underperform other equity funds that employ a different investment style.

Value Investment Style Risk. Different investment styles tend to perform differently and shift in and out of favor depending on changes in market and economic sentiment and conditions. The Fund invests in stocks believed by the Subadviser to be undervalued, but that may not realize their perceived value for extended periods of time or may never realize their perceived value. Thus, the Fund may underperform other equity funds that employ a different investment style.

Sector Risk. To the extent the Fund's investments focus on one or more sectors of the economy, the Fund's performance will be particularly susceptible to conditions and developments relating to such sector(s). For example, the Fund may be more susceptible to the particular risks that may affect companies in the information technology sector, as well as other technology-related sectors (collectively, the technology sectors) than if it were invested in a wider variety of companies in unrelated sectors. In addition, the Fund will be more exposed to price movements affecting companies in such sector(s) than a more broadly invested fund.

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.

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.

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.

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.

Other Investment Companies Risk. To the extent the Fund invests in other investment companies (such as ETFs), the Fund will incur a pro rata share of the expenses of these investment companies and the Fund will be subject to the risks associated with these investment companies. An ETF may trade in the secondary market at a price below or above the value of its underlying portfolio and may not be liquid. In addition, an ETF may not replicate exactly the performance of the index it seeks to track for a number of reasons.

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.

Quantitative Model Risk. There is no guarantee that the quantitative models used by the Subadviser, and the investments selected based on the models, will produce the desired results. Investments selected using quantitative models may not produce the intended results due to the factors and/or assumptions used in the models, the weight placed on each factor and/or assumption in the models, changing sources of market return, and technical issues in the design, development, implementation, and maintenance of the models (e.g., incomplete or inaccurate data, programming or other software issues, and technology failures).

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 and since inception periods compare with those of a broad measure of market performance. 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.

Annual Returns (by calendar year)

Highest Quarterly Return: 10.48% (4th Q 2022)
Lowest Quarterly Return: -10.19% (2nd 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. AllianceBernstein L.P. 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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