The MOE marking on the sidewall of a tyre stands for MERCEDES-BENZ ORIGINAL EXTENDED.
Mercedes has asked manufacturers to develop special tyres that allow flat running, without compromising on comfort. It's true that run-flat tyres are less comfortable than conventional tyres.
The only difference between a run-flat tyre and MOE is the ability to run flat with a loaded vehicle.
The ISO standard for obtaining the 'run-flat' certification requires tyres to be able to drive at 50 mph for 50 miles regardless of the vehicle's load. MOE tyres can travel 50 miles at 50 mph with a light load, and only 20 miles with a heavy load. As a result, MOE tyres aren't eligible for ISO run-flat certification.