# EDGAR Filing Document

**Accession Number:** 0000778207
**File Stem:** 0001193125-25-148017
**Filing Date:** 2025-6
**Character Count:** 4038
**Document Hash:** a688ff04497a67227172e7edbfcc29b3
**Contains OCR:** False
**Source Format:** 

## Filing Content

## Filing Summary
**0001193125-25-148017.hdr.sgml**: 20250626

**ACCESSION NUMBER**: 0001193125-25-148017

**CONFORMED SUBMISSION TYPE**: 497K

**PUBLIC DOCUMENT COUNT**: 1

**FILED AS OF DATE**: 20250626

**DATE AS OF CHANGE**: 20250626

**EFFECTIVENESS DATE**: 20250626

**FILER**: 

**COMPANY DATA:**
- **COMPANY CONFORMED NAME:** TRANSAMERICA SERIES TRUST
- **CENTRAL INDEX KEY:** 0000778207

**ORGANIZATION NAME:**
- **EIN:** 000000000
- **STATE OF INCORPORATION:** DE
- **FISCAL YEAR END:** 1231

**FILING VALUES:**
- **FORM TYPE:** 497K
- **SEC ACT:** 1933 Act
- **SEC FILE NUMBER:** 033-00507
- **FILM NUMBER:** 251075699

**BUSINESS ADDRESS:**
- **STREET 1:** 1801 CALIFORNIA STREET
- **STREET 2:** SUITE 5200
- **CITY:** DENVER
- **STATE:** CO
- **ZIP:** 80202
- **BUSINESS PHONE:** 720-482-8836

**MAIL ADDRESS:**
- **STREET 1:** 1801 CALIFORNIA STREET
- **STREET 2:** SUITE 5200
- **CITY:** DENVER
- **STATE:** CO
- **ZIP:** 80202

**FORMER COMPANY:**
- **FORMER CONFORMED NAME:** AEGON/TRANSAMERICA SERIES TRUST
- **DATE OF NAME CHANGE:** 20050511

**FORMER COMPANY:**
- **FORMER CONFORMED NAME:** AEGON/TRANSAMERICA SERIES FUND INC
- **DATE OF NAME CHANGE:** 20010501

**FORMER COMPANY:**
- **FORMER CONFORMED NAME:** WRL SERIES FUND INC
- **DATE OF NAME CHANGE:** 19920703

## Series and Classes Contracts Data

### Transamerica American Funds Managed Risk VP (Series ID: S000049122)

| Class ID   | Class Name   | Ticker Symbol   |
|:---|:---|:---|
| C000154895 | Service      |  |

**TRANSAMERICA SERIES TRUST** 

**Transamerica American Funds Managed Risk VP** 

**Supplement to the Currently Effective Prospectus and Summary Prospectus** 

**\* \* \*** 

*Effective on or about August 31, 2025, the fifth paragraph of the portfolio's "Principal Investment Strategies" section in the Prospectus and Summary Prospectus and the fifth paragraph of the "More on Each Portfolio's Strategies and Investments" section in the Prospectus relating to the portfolio will be deleted in its entirety and replaced with the following:* 

The portfolio seeks to manage return volatility by employing a managed risk strategy. The portfolio's managed risk strategy seeks to stabilize the volatility of the portfolio around a target volatility level. Managing to the portfolio's volatility target is expected to, on average over time, result in approximately 60% equity related exposure and approximately 40% fixed income exposure. Managing to the target volatility level may, at times, result in the portfolio's exposures varying significantly from this asset mix goal. The sub-adviser may use derivative instruments to accomplish this goal, which may include: equity futures contracts, treasury futures contracts, currency futures contracts, and other derivative instruments judged by the sub-adviser to be necessary to achieve the goals of the managed risk strategy. The sub-adviser may also buy or sell derivative instruments based on one or more market indices in an attempt to maintain the portfolio's volatility at the targeted level in an environment in which the sub-adviser expects market volatility to decrease or increase, respectively. The sub-adviser selects individual derivative instruments that it believes will have prices that are highly correlated to the Underlying Portfolio's positions. The sub-adviser adjusts derivative instruments to manage overall net portfolio risk exposure, in an attempt to stabilize the volatility of the portfolio around a predetermined target level and reduce the potential for portfolio losses during periods of significant market declines. The sub-adviser seeks to monitor and forecast volatility in the markets using a proprietary model, and adjust the portfolio's derivative instruments accordingly. In addition, the sub-adviser will monitor liquidity levels of relevant derivative instruments and transparency provided by exchanges or the counterparties in derivatives transactions.

**\* \* \*** 

**Investors Should Retain this Supplement for Future Reference** 

**June 26, 2025**