Pluristem Therapeutics Inc (PSTI)

[zzaatt]

But today I understood the real reason why plx pad was not given to any patient.
The reason is lack of efficacy in phase 3 .

Of course that's pure speculation (which doesn't mean that it's wrong)

A counter argument is that they partnered with Charité to work on covid-19 is that they (Pluristem) thought that it has some chance of working. Why else would they?

You speculate that there's a lack of efficacy. In other words they tried and failed. There's no indication that this actually happened. I think we just have to wait and see.