New sponsors, in particular start-ups, of future orphan drugs often wonder what level of scientific evidence is needed to fulfill the scientific rationale criterion required to obtain the orphan status designation. In a recent editorial in Drug Discovery Today (available on line 22 dec 2011), the FDA & Keck Graduate Institute provide a quantitative description of the scientific rationale upon which promising compounds have been designated as orphan drugs in 2009. Using summary statistics of proprietary FDA-held data the paper describes the basis upon which designated products fulfilled the scientific rationale criterion in 2009 (N=160 OD).
Most interesting features were :
- The most advanced level of evidence was Clinical experience (66%), Animal models (32%) and in vitro studies (2%)
- Of “Clinical experience” orphan designations the median number of enrollees was 46 study subjects, and 53% had an active IND
The authors further explain and provide a number of reasons why “despite the animal model option for demonstrating scientific evidence in support of orphan designation, sponsors often apply only after gathering data from clinical experience”.
Data provided in the editorial include type of product and disease class, but suprisingly not the sponsor itself (e.g. SME or Large pharma company). The latter would have been very interesting, because it could have given more insight into the decision-making process by sponsors. Perhaps this will be included in a follow-up study.
Hyperlink to editoral at publisher site: http://www.sciencedirect.com/science/article/pii/S1359644611004417
Authors are Daniel Lev, Chandana Thorat, Ian Phillips (Keck Graduate Institute) and Mathew Thomas, Menfo A. Imoisili (FDA). Corresponding author is Menfo A. Imoisili
If you are interested in quantitative descriptions of the (pre-)clinical development stage of (European) orphan drugs with a marketing authorization. I can highly recommend a paper by Joppi et al. published in Br. J. Clin. Pharmacol. in 2009: http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2686065/?tool=pubmed
There is much more out there……….