The original question during the webinar was: My design is analogic measurement current in an isolated high tension (25 kV) system. Sometimes, we have breakdowns, and we have damage (aop 1st stage AD4610 or a voltage regulator (+5 V or -15 V or +15 V). I tried to insert protective components without performance loss. I measured 5 nA current and some TVS diodes have leakage current 1 or 10 or 100 nA. Any useful reference in future can be test, it might be differential measurement.
For that specific case, 2 ESD protections on common mode may be better than a single ESD protection in differential. We recommend ESDZV5H-1BU2 for +/-5 V and ESDLC20-1BF4 for +/-20 V.