EU/3/02/122

On 13 November 2002, orphan designation (EU/3/02/122) was granted by the European Commission to Laboratoires SERB, France, for etilefrine for the treatment of low flow priapism.

What is low flow priapism?

Low flow priapism is a medical disorder in which there is persistent erection of the penis in the absence of sexual interest. Patients with low flow priapism usually present with a history of several hours of painful erection. It is believed that this condition is caused by obstruction to the normal drainage of blood from the erectile tissues. This obstruction causes buildup of poorly oxygenated blood. If the process continues for several days, abnormal thickening and scarring of the erectile tissue may develop, causing impotence. Low flow priapism is a serious and debilitating disease if it is not treated adequately and promptly.

What are the methods of treatment available?

There are no medicinal products that have been authorised for the treatment of priapism in the Community. Treatments which are currently used include medical treatment, for instance with medications consisting of certain adrenalin-like substances (alpha adrenergic agonists) or, if necessary, surgical procedures.

What is the estimated number of patients affected by the condition*

According to the information provided by the sponsor, low flow priapism is considered to affect about 4,100 persons every year in the European Union.

*Disclaimer: The number of patients affected by the condition is estimated and assessed for the purpose of the designation, for a European Community population of 377,000,000 (Eurostat 2001) and may differ from the true number of patients affected by the condition. This estimate is based on available information and calculations presented by the sponsor at the time of the application.

How is this medicinal product expected to act?

Etilefrine is a substance that stimulates the sympathetic nervous system. This system is involved in regulating several processes such as pulse, blood pressure, and the tone of smooth muscle. The erection of the penis depends on the relaxation of the smooth muscle of the two columns of erectile tissue at either side of the penis (corpora cavernosa). The relaxation causes widening of the blood vessels and the tissue is filled with blood causing the erection. The injection of etilefrine inside the corpora cavernosa leads to a decrease in the blood supply to the penis and may also increase the drainage of blood from the erectile tissues. It is expected that this will produce a gradual reduction in the erection.

What is the stage of development of this medicinal product?

At the time of submission of the application for orphan designation no clinical trials in patients with low flow priapism had been initiated. Etilefrine had not been marketed anywhere worldwide for low flow priapism or designated as orphan medicinal product elsewhere for this condition, at the time of submission.

According to Regulation (EC) No 141/2000 of 16 December 1999, the Committee for Orphan Medicinal Products (COMP) adopted on 9th October, 2002 a positive opinion recommending the grant of the above-mentioned designation.

Opinions on orphan medicinal products designations are based on the following cumulative criteria:

(i) the seriousness of the condition, (ii) the existence or not of alternative methods of diagnosis, prevention or treatment and (iii) either the rarity of the condition (considered to affect not more than five in ten thousand persons in the Community) or the insufficient return of development investments.

Designated orphan medicinal products are still investigational products which have been considered for designation on the basis of potential activity. An orphan designation is not a marketing authorisation. As a consequence, demonstration of the quality, safety and efficacy will be necessary before this product can be granted a marketing authorisation.