Toshiba announced their enterprise SSD based on PCIe 4.0m and these units are capable of a sequential read performance of over 6.4GB/s.
The CM6 Series SSDs support dual-port PCIe Gen4 x4 lanes and are NVMe 1.4 compliant. The family of enterprise NVMe SSDs will be available in a 2.5-inch form factor with capacity points from 800GB to 30TB, and 1 or 3 drive writes per day endurance options. The volume sizes start at 800 GB and run towards a massive 30 TB over a U.2 connector. Of course, to take full advantage of SSD speeds, the host product must also benefit from PCIe 4.0.
Toshiba CM6: Server SSDs with PCIe 4.0, 6,400 MB/s and up to 30 TB