Yes, but in fact it's the opposite. One of the big advantages of fusion is that you operate on very small amounts of fuel at any given time. Maybe a second's worth would be in a power plant at any given time. Even if things go perfectly right and you manage to get the reaction going, which is hard, then it consumes the available fuel very quickly, so there's no chance of a runaway reaction.
At the same time, because those conditions are very difficult to achieve, if anything breaks in the machine and you don't achieve those conditions at all, then the reaction just doesn't happen. It's unlike fission, which is a spontaneous reaction. In fusion you have to work very hard to achieve those conditions. From that point of view, it's fundamentally fail-safe.
It also has the benefit of not using uranium or plutonium fuels, meaning you do not have the highly radioactive long-lived waste produced as a stream from the fusion reaction. It doesn't mean that there's no radioactivity at end of life; you'll have components like in a nuclear medicine clinic, or like in a fission reactor, that are activated. They need to be treated and carefully handled, but those are decadal time spans and not millennial-long. Its safety profile is actually one of the very attractive features of fusion.