Raptor Pharmaceuticals announced that the FDA has granted orphan drug designation for cysteamine bitartrate for the treatment of Huntington’s disease. Cysteamine is currently approved by the FDA and European Medicines Agency to treat nephropathic cystinosis*, also an orphan designation.
In addition to the targeted orphan designation, it appears that Raptor is also trying to improve on the current Mylan product. The Raptor product is enteric coated, a process which allows the product to pass through the acidic stomach and release in the intestine as the fluids become more basic. This move is prudent because it would avoid the eventual competition/substitution.
What is Raptor’s strategy? Could they be applying for a 505(b)(2) on the current product, with just pharmacokinetic studies to gain approval of the enteric-coated product versus the current product? That might help pay the bills while the new indication is being studied.
In the development of a new 505(b)(2) product, especially those with a new indication, it is mandatory to determine a generic defense strategy. It is also highly desirable to develop a product life extension strategy.
*Nephropathic cystinosis is a rare inherited condition which causes the build up of a protein building block called cystine in the kidneys. The build up of cystine causes kidney problems. These kidney problems cause the body to lose too much sugar (glucose), proteins, and electrolytes. Cystinosis may lead to slow body growth, weak bones and worsening kidney failure.