I asked Pavel Podvig about the PRS-1, he claims it was developed by Novator for the S-225 as the 5Ya26, to complement Fakel's 5Ya27. The 53T6 GAZELLE is a different weapon which replaced the PRS-1 when the S-225 was cancelled and was a Novator product, explaining the perceived similarities with Novator's 9M82/83 weapons for the S-300V.

The S-225 was intended to defend cities and other strategic point targets from limited ICBM strikes.