No it doesn’t but they're available as a custom option.
Side Note: If the combined weight of the trailer and its load approaches or exceeds 3,000 pounds, many jurisdictions require brakes on the trailer. However, a 4x6 enclosed trailer, given its size, is unlikely to reach this weight limit when fully loaded, as they typically have a lower payload capacity.
Safety Considerations
Driving Conditions: If you plan to tow your trailer in hilly or mountainous areas, or if you'll be driving in a lot of stop-and-go traffic, having electric brakes can significantly improve safety by reducing stopping distances and improving vehicle control.
Emergency Handling: Electric brakes can offer better control in emergency braking situations, reducing the risk of accidents.
Wear on Vehicle Brakes: Using a trailer with its own braking system can reduce wear and tear on your vehicle's brakes, especially important for frequent towing or heavy loads.