Drugs for rare diseases: mixed assessment in Europe

(1) Worldwide, there are an estimated 6000 to 7000 rare diseases. Patients face special difficulties in obtaining an accurate diagnosis, adequate information about the disease, and access to qualified specialists. (2) Drug companies do not spontaneously conduct research on drugs for rare diseases, mainly because of the limited market for each indication. Only a few dozen of these drugs were available in France before 2000. (3) In 2000 the European Union adopted a Regulation, based on experience in the United States, aimed at promoting the development of drugs for patients suffering from rare diseases, i.e. 'orphan drugs'. (4) In Europe, orphan drug status can be granted when the prevalence of the disease does not exceed 5 cases per 10 000 inhabitants (or when it is more frequent but profitability is likely to be inadequate). (5) Companies that market an orphan drug receive a variety of financial assistance as well as a 10-year marketing monopoly. (6) Between April 2000 and April 2005, 268 medicinal products received European orphan drug status and 22 were granted European marketing authorization. (7) Access to these drugs varies greatly from one European Union Member State to another, mainly because of the high annual treatment costs (up to 300 000 euros per patient). Worldwide sales of the orphan drug imatinib reached more than two thousand million dollars in 2005. (8) Our systematic analyses (see the New Products column of our French edition la revue Prescrire) show that only 5 drugs which received European orphan drug status before May 2005 were for diseases for which there had previously been no treatment. (9) Clinical evaluation of orphan drugs is hindered by the small number of patients available for clinical trials. Some orphan drugs are adequately tested before being brought to market. Others are not compared to existing treatments. In many cases, surrogate criteria are used instead of clinical endpoints. These methodological flaws are in no way limited to orphan drugs. (10) Not all orphan drugs represent therapeutic advances. Clinical research and evaluation should continue after marketing authorization has been granted. (11) More drugs, with better-documented efficacy and safety, are now available for patients who previously had no effective treatment options. Yet there is too much duplication and too little evaluation, and too many drugs are extremely expensive, meaning that patients in many European countries cannot benefit. And many rare diseases are still neglected.