Randomized, double-blind study for the evaluation of the effect of losartan versus placebo on aortic root dilatation in patients with Marfan syndrome under treatment with beta-blockers.

INTERVENTION: Trade Name: Cozaar Product Name: Losartan Pharmaceutical Form: Film‐coated tablet INN or Proposed INN: Losartan potassium CAS Number: 124750998 Concentration unit: mg milligram(s) Concentration type: equal Concentration number: 50‐ Pharmaceutical form of the placebo: Capsule* Route of administration of the placebo: Oral use Trade Name: Coozar Product Name: Losartan Pharmaceutical Form: Film‐coated tablet INN or Proposed INN: Losartan potassium CAS Number: 124750998 Concentration unit: mg milligram(s) Concentration type: equal Concentration number: 100‐ Pharmaceutical form of the placebo: Capsule* Route of administration of the placebo: Oral use Trade Name: Coozar Product Name: Losartan Pharmaceutical Form: Film‐coated tablet INN or Proposed INN: Losartan potassium CAS Number: 124750998 Concentration unit: mg milligram(s) Concentration type: equal Concentration number: 25‐ Pharmaceutical form of the placebo: Capsule* Route of administration of the placebo: Oral use CONDITION: Marfan syndrome ; MedDRA version: 9.1 Level: LLT Classification code 10026829 Term: Marfan's syndrome PRIMARY OUTCOME: Main Objective: To study the effect of losartan (an angiotensin receptor blocker ‐ARB) on aortic root growth in patients with Marfan syndrome, already treated with beta‐blockers (BB). Primary end point(s): The decrease of rate of aortic root growth measured by echocardiography at the level of sinuses of Valsalva. The measure will be expressed in mm of growth per year and as Z‐score. Secondary Objective: INCLUSION CRITERIA: • Patients > 10 years • Diagnosis of MFS, according to the Ghent criteria and/or genetically proven FBN1 mutations or linkage • Consent obtained (written) either for the patient and for his/her parents (<18y) • Z‐score of the aorta at the level of the sinus of Valsalva =2 (BSA adjusted) • ARB naïve patients Are the trial subjects under 18? yes Number of subjects for this age range: F.1.2 Adults (18‐64 years) yes F.1.2.1 Number of subjects for this age range F.1.3 Elderly (>=65 years) yes F.1.3.1 Number of subjects for this age range