After Object 223 was finalised as the design for the KV-3, the 107mm ZiS-6 cannon was made a requirement for the main weapon of a new super-heavy tank to be produced as the KV-4. Twenty-seven different designs were submitted for the project, some very similar to each other, while others were radically different from any tank yet built, Soviet or otherwise. Among the designers to submit a proposal for the KV-4 project was Nikolai Fëdorovich Shashmurin, who had already worked on both the SMK and KV-1. Shashmurin showed his apparent preference for the SMK in his KV-4 design, Object 901, which was one of the largest submitted (but far from the heaviest), with nine pairs of road wheels supporting 92 tonnes. According to Shashmurin’s own memoirs, his design was ultimately selected for the KV-4 project, in spite of other designers deriding it as a glorified self-propelled gun. However, regardless of which design was selected, the KV-4 project was cancelled when the Wehrmacht attacked Leningrad, and no prototype was ever constructed.
You can see more information about all the designs submitted here. This is a Russian Wikipedia link, and while there is an English page titled “KV-4,” it shows only the drawings, and does not contain any of the information that the Russian page does.
Unknown № 1
Project Dukhov (the KV-4 as it currently appears in World of Tanks)
Project Kuzmin, et al (known as KTTS in World of Tanks)
Project Strukov (the KV-4 as it used to appear in World of Tanks)