In a case being watched by advocates for patients with anorexia and bulimia, a federal judge in Newark, N.J., has ruled that class action lawyers can pursue an attempt to compel Aetna Inc. to improve benefits for eating disorder victims.

U.S. District Judge Faith Hochberg on Wednesday denied a dismissal motion, in which the insurer argued the coverage dispute should be decided by state regulators or by its own internal review process on a case-by-case basis.