Bright white light, faster than a satellite and much slower than a meteor, which faded and disappeared.

My husband and I were enjoying the perseids meteor shower.  We saw several aircraft, all going east-west, which were easily identified by their flashing red lights and subsequent sound.  
At 23:24 we both spotted a fast-moving white light which had no red lights and was traveling north to south.  We agreed it was not a plane.  It was moving faster than satellites but much slower than the meteors.  
As we watched the light continue along its trajectory, it began to fade, blinked bright, then disappeared.  It was definitely not a meteor.  It left no tail nor was it moving as fast as the meteors we viewed.  
We waited to see if it would reappear along its trajectory but it never showed up.  It was not the satellite Integral (which hardly moves at all), although it was in the same general vicinity. 
Nor was it Genesis I which passed one hour later and low on the horizon.  We were at lat 38.92 and long-107.91.  
The object was about 60 degrees above the horizon to the NNE near the star Alderamin.