Investigate Efficacy, Safety, and Pharmacokinetics of Enzastaurin for the Prevention of Arterial Events in Patients With Vascular Ehlers-Danlos Syndrome.

The primary efficacy endpoint of this study will be defined as the time to intervention for an arterial event (rupture, dissection, pseudoaneurysm, carotid-cavernous sinus fistula, or aneurysm, fatal or not) or mortality attributable to an arterial event, as adjudicated by an Event Committee, and will be analyzed for difference of active vs. placebo treatments on top of background standard of care, using survival statistical analysis. Furthermore, secondary endpoints will include the rate of intestinal rupture, pneumothorax, and retinal detachment, as adjudicated by an Event Committee, safety and tolerability, as well as hospitalizations and Health Related Quality of Life (HQRL) measures.

• Enzastaurin (Drug): 500 mg QD orally in the form of four 125 mg tablets with background standard of care
• Placebo (Drug): Placebo to match enzastaurin 500 mg QD orally in the form of four 125 mg tablets with background standard of care

Primary outcomes

• Time to intervention for an arterial event (rupture, dissection, pseudoaneurysm, carotid-cavernous sinus fistula, or aneurysm, fatal or not) or mortality attributable to an arterial event. [30 months]: Time to intervention for an arterial event (rupture, dissection, pseudoaneurysm, carotid-cavernous sinus fistula, or aneurysm, fatal or not) or mortality attributable to an arterial event, as adjudicated by an Event Committee and analyzed for difference in the time-to-composite-event of active vs. placebo treatments, using survival analysis until end of study

Secondary outcomes

• Number of and proportion of patients with adverse events, or with abnormal vital signs, physical examinations, ophthalmological examinations, clinical laboratory values, or electrocardiograms (ECGs) medical attention. [30 months]: An Adverse Event (AE) is defined as any untoward medical occurrence associated with the use of the investigational product in humans, whether or not considered related to investigational product. An AE can be any unfavorable and unintended sign (e.g., an abnormal laboratory finding), symptom, or disease temporally associated with any use of the investigational product, without any judgment about causality and irrespective of route of administration, formulation, or dose, including an overdose.
• Number of and proportion of patients who discontinue study drug due to adverse events [30 months]: Discontinuation or withdrawal from the study

Sex: All, ages: 18 Years to 60 Years

Inclusion Criteria:

1. Subjects aged 18 - 60 years old at time of initial screening.
2. Adolescent subjects aged 12 - 17 years old, may be considered to enroll later in the clinical trial pending interim analysis.
3. Diagnosis for VEDS (vascular Ehlers Danlos Syndrome), with a confirmed and documented COL3A1 genetic variant.
4. Subject should be stable, having no VEDS-related vascular events within the past 3 months prior to enrollment.
5. Confirmed use of contraception for both male and female participants.

Exclusion Criteria:

1. Inability to swallow or receive intact tablets.
2. Currently being treated with CYP3A4 inhibitors within 4 weeks prior to enrollment.
3. Known allergy or hypersensitivity to enzastaurin.
4. Patient currently pregnant or breast feeding.

Other criteria will be reviewed at the first study visit to determine if you are able to participate in the study.

• Bowen CJ, Calderon Giadrosic JF, Burger Z, Rykiel G, Davis EC, Helmers MR, Benke K, Gallo MacFarlane E, Dietz HC. Targetable cellular signaling events mediate vascular pathology in vascular Ehlers-Danlos syndrome. J Clin Invest. 2020 Feb 3;130(2):686-698. doi: 10.1172/JCI130730. PMID 31639107

• Sherene Shalhub, M.D., M.P.H., Principal investigator, University of Washington
• Shaine Morris, M.D.,M.P.H., Principal investigator, Texas Children's Hospital and Baylor College of Medicine