Ranibizumab to Treat Choroidal Neovascularization (CNV) in Patients With Pseudoxanthoma Elasticum (PXE)

Pseudoxanthoma elasticum (PXE) is a rare hereditary systemic disease affecting mainly the skin, eyes and the cardiovascular system. Commonly, complicating choroidal neovascularization (CNV) of the central retina lead to a severely decreased visual acuity in the course of the disease. Onset of the symptoms varies with the extend of the PXE-associated findings.

In the past there has been no effective treatment for the disease's ocular complications. Recent studies in a limited number of patients with CNV treated with intravitreal injections of bevacizumab, an antagonist targeting vascular endothelial growth factor (VEGF), have shown a preservation of function and regression of CNV. An increase of visual acuity was reported in a subset of patients. Bevacizumab is a humanized antibody of which ranibizumab is a fragment.

This trial is initiated in order to investigate the effect of ranibizumab on functional outcome measures such as preservation of visual acuity as well as morphological outcome measures such as regression of CNV in angiography.

The safety and tolerability of ranibizumab will be investigated as well. As it has been tested on large numbers of patients suffering from age-related macular degeneration with only rare significant side effects or adverse events being reported, a good safety profile is assumed.

The study is conducted in a non-randomized, uncontrolled prospective setting at one center.

Patients will receive monthly injections over a period of one year.

Inclusion criteria

• Diagnosis of choroidal neovascularization in patients with pseudoxanthoma elasticum
• Age between 18-65 years
• Patient must be able to follow protocol
• Written informed consent
• Genetic diagnosis of pseudoxanthoma elasticum
• Best corrected visual acuity between 20/200 - 20/32 in the treated eye

Exclusion criteria

• Patients who do not fulfill the inclusion criteria
• Patients with other retinal vascular diseases such as diabetic retinopathy or venous occlusive disease
• Ocular surgery 3 months before study enrollment
• History of uncontrolled glaucoma
• Active intraocular inflammation or inflammation of the ocular adnexa
• Subfoveal fibrosis in the study eye
• Inability to follow study protocol
• Major surgery one month before study enrollment
• History of severe cardiovascular disease or history of stroke 6 months before study enrollment
• Allergies against the substances or components of the study medication
• Low anticipated compliance
• Patients who participated in clinical trials simultaneously or within the last 60 days
• Pregnancy, lactation, women that may become pregnant and don't use safe contraception
• Chronic alcohol- or drug abuse within the last year
• Lacking legal competence or language ability
• Neurologic diseases such as multiple sclerosis
• Need of concomitant medication that is not allowed in combination with ranibizumab
• Previous intravitreal therapy with anti-angiogenic substances in the study eye within the last 6 months