DragonSpeed will leave the World Endurance Championship's LMP1 class at the end of the 2018/19 superseason to focus on IndyCar in 2020, says team boss Elton Julian.
The team will continue to race in LMP2 at selected races during the 2019/20 WEC season.
A DragonSpeed statement said the decision had been made to focus the team's "energies on expanding its current schedule of selected IndyCar Series events in 2020."
Julian added: "The Le Mans 24 Hours next month will be our final LMP1 and regular WEC outing, allowing us to ramp up our IndyCar efforts on both the technical and marketing fronts.
"We're not leaving the WEC completely, as we plan to enter our number 21 LMP2 ORECA O7-Gibson in individual rounds, including Spa, Brazil and Le Mans, with Le Mans of course subject to us earning or being granted an invitation.
"We're also considering running Daytona and Sebring with IMSA again.
"We'll definitely be continuing in the [European Le Mans Series], which we think offers the best sportscar racing on the planet and remains the ideal series for the top gentleman drivers.
"With the kind of competition you get from 19 regular LMP2 entries, we take pride in the fact that the last two ELMS victories with a bronze driver, in 2016 and '19, have been ours.
"For us, the potential for growing DragonSpeed as an engineering and commercial concern is far clearer in IndyCar than anywhere else in the sport, given the quality of racing and stable formula. That's what's driven our decision."
DragonSpeed is attempting to start the Indianapolis 500 for the first time in 2019, with driver Ben Hanley.