FDA advisory committee: Efficacy of Vitrase not proven

GAITHERSBURG, Md. — An advisory committee of the Food and Drug Administration yesterday opted against recommending the approval of a drug for the treatment of vitreous hemorrhage because of insufficient efficacy data.

The Dermatology and Ophthalmic Advisory Committee voted 8 to 4 that Ista Pharmaceuticals did not provide sufficient evidence proving the efficacy of Vitrase (ovine hyaluronidase for intravitreal injection) for the treatment of vitreous hemorrhage. However, the panel voted 7 to 5 that the benefits of using Vitrase outweigh the risks in treating the condition.

Lisa R. Grillone, PhD, said two placebo controlled and double masked clinical trials, including one of about 1,300 patients, were combined to form the data presented to the advisory committee. The primary endpoint of the study was surrogate success, defined as clearly documented clearance of the hemorrhage, diagnosis and subsequent treatment of underlying pathology, if treatment is required.

The reduction in hemorrhage density and improvement in best-corrected visual acuity also were evaluated.

Patients included in the study were required to have severe vitreous hemorrhage for at least 1 month. Best corrected visual acuity had to be worse than 20/200 in the study eye. Patients received a single injection of the drug or placebo and were followed to 3 months. Dr. Grillone said the drug showed significant efficacy early after dosing only.

A minority of members of the committee, including C. Pat Wilkinson, MD, from the department of ophthalmology, Greater Baltimore Medical Center, said the end points were not optimal for a drug of this kind, “but there does appear to be a slight improvement in vision and peripheral visualization.”

Ming T. Tan, MD, PhD, from the University of Maryland, Department of Epidemiology and Preventative Medicine, said one of the understated benefits of the drug was improved diagnosis of underlying disease and requested additional information on this aspect.

A majority of the panel also indicated additional analysis of the drug is needed, especially on how the drug interacts with currently available treatments such as vitrectomy.

The FDA is considering Vitrase on a fast-track basis because there are no approved drugs for the treatment of severe vitreous hemorrhage.