Response to Oral Lansoprazole of Inorganic Pyrophosphate Levels in Patients With Grönblad-Stranberg Disease (Pseudoxanthoma Elasticum)

Protocol code and version: FIM-PXE-2016-01 Version 1.4 Trial title: "Response to oral lansoprazole of inorganic pyrophosphate levels in patients with Grönblad- Stranberg disease (Pseudoxanthoma Elasticum)" Trial design: Double-blind, placebo-controlled, randomised, two-stage crossover clinical trial, with each patient serving as their own control and reducing the number of patients to confirm our hypothesis. Principal Investigator: Dr. Pedro Valdivielso Felices Participating centres Virgen de la Victoria's Universitary Hospital in Malaga and Virgen de la Macarena's Universitary Hospital in Seville. Duration of the trial: 12 months Expected start date: December 2019 Objectives: Principal:To verify the changes in plasma PPi, and the main molecules that regulate it (NPP1-3, TNAP) after oral administration of lansoprazole in patients diagnosed with PXE. Description of treatment: Selection:20 patients who meet all the criteria for inclusion and none for exclusion. Randomisation and 1st stage: Patients will receive lansoprazole 30mg/day or their placebo for 8 weeks. Wash-out: After 8 weeks, all treatment will be suspended for 15 days. 2nd stage (crossed): Treatment is crossed, each patient serves as his or her own control. Evaluation variables: 1. Date of Birth 2. Sex. 3. Physical examination (anthropometry and vital signs) 4. Date of first symptom. 5. Date of final diagnosis 6. Ocular affectation (orange peel skin, complete striae angioides, lucentis, corrected visual acuity, cataracts, intraocular pressure, fundus (vascular flow, optic nerve drusen, retinal atrophy, neovascular membranes, macular thickness, colloid thickness). 7. Skin affectation (yellowish papules or plaques on the side of the neck or other areas of flexure and lax skin). 8. Vascular affectation (intermittent claudication clinic, angina and/or episode of acute myocardial infarction and/or non-embolic ischemic stroke, surgical or percutaneous revascularisation, cardiac murmur,10.) 9. History o