DeCure for Posterior polymorphous corneal dystrophy 1

In 1983, four families with posterior polymorphous corneal dystrophy of Schlichting were studied; nine persons had typical lesions. Two families suggested dominant inheritance, one with less than 100% penetrance, and there were two sporadic cases. No corneal oedema was present, and central corneal thickness was normal, indicating the corneal endothelium in this dystrophy can maintain a normal hydrated cornea. A 1989 report described four young men with both keratoconus and posterior polymorphous corneal dystrophy; all showed central corneal steepening and irregularity, plus large areas of irregular polymorphous opacification at the level of Descemet’s membrane in at least one cornea each.

A 1985 study examined cornea and iris from a 58-year-old man with posterior polymorphous corneal dystrophy by light and electron microscopy. That patient was the son of a woman previously reported to have Chandler’s syndrome; the report discussed clinicopathologic features of both diseases in light of controversies surrounding their differential diagnosis. A 1992 review noted that basic science research was uncovering information that these disorders may not all be solely corneal abnormalities, and that a systemic disorder might help explain the high recurrence rate of certain corneal dystrophies after penetrating keratoplasty.

A 2016 review of International Committee for Classification of Corneal Dystrophies category 1 corneal dystrophies, for which a clear genetic link has been established, discussed mechanisms including structural disorganisation, instability or maladhesion, aberrant protein stability and deposition, abnormal cellular proliferation or apoptosis, and dysfunction of normal enzymatic processes. The review stated that understanding these genetic mechanisms is essential for designing targets for therapeutic intervention, especially in the age of gene therapy and gene editing. No abstract in this set reports any drug tested in posterior polymorphous corneal dystrophy, no clinical trial data, no survival or response rates, and no molecular target for a drug intervention. What is still missing is any funded clinical trial, any identified drug candidate, any patient stratification strategy, and any animal model data that could support a repurposing hypothesis.