No, if it were related to “safety” as you suggest, then the regulators would make it a 1) public event; 2) disclosures would have been necessary, as you need to update the consent; 3) the placebo patients would not have been the only arm to be reduced. Instead, the regulators never disclosed why. You surmised a reaction which they knew about for years, and suggest it would be serious suddenly, enough to cause a “partial halt” that the regulators did not even publicly announce.
I’ve never seen that occur where a treatment was causing “harm” to patients. Regulators are very clear about their own duties to prevent harm, they do not beat around the bush, nor do they quietly put “partial halt” on a trial website in Germany and hope no one notices. That’s not how a safety issue gets announced.
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