Elmiron (Pentosan Polysulfate Sodium)

The Elmiron MDL was centralized in December 2020 to coordinate claims alleging that pentosan polysulfate sodium, marketed as Elmiron and used to treat interstitial cystitis (a chronic bladder-pain condition), is associated with a distinctive form of retinal toxicity — pigmentary maculopathy — that can develop after years of use and cause permanent vision impairment. With 286 actions pending, this remains an active, moderately sized docket built around a comparatively novel and specific injury mechanism relative to more commonly litigated drug-safety theories.

What drives duration and resolution risk in this docket is centrally a dose-and-duration causation question: because the alleged retinal toxicity is associated with cumulative, long-term exposure rather than any single dose, causation proof depends heavily on establishing years of documented use alongside objective retinal-imaging findings consistent with the specific maculopathy pattern associated with the drug, as opposed to age-related or other unrelated retinal conditions that can present similarly. That differential-diagnosis element is a distinguishing feature of this litigation relative to many other pharmaceutical mass torts, where causation more often turns on epidemiological association rather than individualized diagnostic differentiation.

Because the injury has a long latency and diagnosis depends on specialized ophthalmologic evaluation, this docket's claims population has developed more gradually than a mass tort tied to an acute or short-latency injury, and that gradual development pattern continues to shape the pace at which the docket accumulates and resolves claims. It also means the docket's eventual resolution path may look less like a single compressed settlement event and more like a series of claim waves tracking when different cohorts of long-term users reach the point of a confirmed diagnosis.

Criterica Intelligence treats this kind of cumulative-exposure, diagnosis-differentiation-driven causation pattern as its own structural category — distinct from both acute-injury device torts and single-exposure environmental-contamination claims — and surfaces that distinction as part of its broader structural read across the active MDL landscape.