According to the manufacturer, yes. Also, various users report that you can wear the device comfortably during sleep. Traditional penile extenders typically fall off while the wearer is sleeping due to movement and spontaneous erections. But, the manufacturers considered these problems when designing the Phallosan Forte, and its unique design means that most people can wear it at night.
The device draws the penis to the side and allows for movement. It also expands with the penis should you have an erection.
However, wearing the device at night may be risky, so to stay on the safe side, consider wearing the device in the daytime only.