On February 22, 2017, Minoryx Therapeutics’ lead pipeline asset, MIN-102, received Orphan Drug Designation from the FDA, following the decision by the European Medicines Agency (EMA) to award the same designation just two months ago. Its Phase II/III trial is expected to start in H2 2017.
MIN-102 aims to target X-linked adrenoleukodystrophy (X-ALD), a life-threatening orphan central nervous system (CNS) disease. There are currently no approved treatments for this rare genetic disease, and as such, there is a huge unmet medical need. X-ALD is caused by mutations in the ABCD1 gene, resulting in the accumulation of very long chain fatty acids (VLCFA), which in turn leads to rapid neurodegeneration of the most affected tissues: the spinal cord, the brain, and the adrenal cortex.
X-ALD offers a small market for pharma companies, given it is estimated to occur in approximately 1 in 17,000 births. Besides MIN-102, there are another seven pipeline drugs targeting this rare indication, of which two also have secured an Orphan Drug Designation from the FDA, Bluebird Bio’s Lenti-D and Viking Therapeutics’ VK0214. Despite the small size of the market, the pipeline indicates that competition is heating up in an effort to gain the first-to-market position. In addition, the first Orphan Drug Approval for this indication will also secure seven years of market exclusivity in the US, and 10 years in Europe.
X-ALD can present in several forms depending on the severity of phenotype and the age of onset; MIN-102 is the only pipeline drug for potential use across the two main phenotypes, adrenomyeloneuropathy (AMN) and cerebral ALD (cALD). This could enable the drug to have the upper hand, once it reaches the market. One concern, however, is that its main competitor, Lenti-D, which is being developed as a potential one-time treatment to halt the progression of cALD, could be the first therapy approved for this indication, given this gene therapy is already undergoing Phase II/III trials. However, there can be no assurance that the FDA and EMA will not require additional studies prior to Lenti-D’s approval. The FDA has already advised Bluebird Bio that its current trial may not be deemed to be a pivotal study and therefore the company may need to conduct additional clinical studies for its gene therapy prior to a Biologics License Application (BLA) submission. In the long run, this may enable MIN-102 to get ahead of the race if it continues to show robust results in its latestage trials.