Still, if people are currently concerned about their drinking water while any potential toxicity is yet to be evaluated, study author David Wahman said in the briefing that previous literature has shown the by-product to be removed by activated carbon.
And of course they don’t say if it’s filterable.
Edit: https://www.cbsnews.com/news/chloronitramide-anion-chemical-drinking-water-toxicity/
So a standard Britta-like filter is all you need.