Wednesday, October 10, 2012

Xenoport eying a prodrug of BG-12 that would improve compliance and tolerability

Xenoport reported Phase I data on its XP-23829 a treatment for Multiple Sclerosis. XP-23829 is in Phase 1 trials and is  a a prodrug of BG-12 (dimethyl fumarate), which is currently waiting regulatory approval. Having shown superior efficacy compared to Copaxone (the current gold standard treatment in MS) BG-12 is poised to become the new
gold standard in the treatment of Multiple sclerosis. Unlike other treatments that currently work in first line MS (interferons, Copaxone)  BG-12 also offers the convenience of oral administration. In pivotal clinical trials, BG-12 has shown  the best effiacacy and safety data in Multiple sclerosis.

In Head to head trials comparing BG-12 to Copaxone (~ 40% market share) , BG-12 cut ARR (relapse rates) at two years by 45% (when taken thrice daily) as compared to just 29% with Copaxone.

Although BG-12 is administered orally, but has to be taken thrice daily which is inconvenient. BG-12 is also associated with skin flushing, stomach cramps, diarrhea, and vomiting, mostly during the first few weeks of treatment.

With its prodrug candidate XP-23829 Xenoport is attempting to develop a more convenient treatment option (once daily dosing) that could also cut down safety issues. In the Phase 1 trials, Xenoport studied five different formulations of BG-12 in order to reach to the option that would truly offer once daily dosing advantage (without compromising on efficacy and safety)