Manufacturers of prescription opiates lost a key ruling Monday involving public nuisance claims as pressure against them mounts ahead of a closely watched trial next month.

U.S. District Judge Dan Polster of the Northern District of Ohio, who will oversee the Oct. 21 jury trial, refused to toss claims that the opioid manufacturers, which include Purdue Pharma and Johnson & Johnson, created a public nuisance. The ruling applies to two Ohio counties serving as plaintiffs in the first federal trial over the opioid crisis.