Celgene pre-ASH release provides new positive data on luspatercept

This morning abstracts for the American Society of Hematology (ASH) meeting became available online, showing data from the Phase III luspatercept studies in myelodysplastic syndromes (MDS) and beta-thalassemia that were not previously disclosed in the top-line press releases by Celgene (Nasdaq: CELG), whose shares were up 4.83% at $75.06 by late morning trading.

In the MEDALIST MDS trial luspatercept resulted in a 38% rate of red blood cell transfusion independence (RBC-TI) versus 13% in placebo-treated patients. In the BELIEVE beta-thalassemia study 21% of luspatercept-treated subjects had a >33% reduction in transfusion burden versus just 5% receiving placebo. Luspatercept has been touted as a $2 billion drug.

These results are incrementally positive and confirmatory for luspatercept in both indications and make regulatory approval seem a near certainty, commented Leerink Research analyst Geoffrey Porges. It would make sense to him that both Acceleron Pharma (Nasdaq: XLRN) and Celgene’s stocks would react positively to this disclosure since regulatory approval for this very important asset appears to be a near 100% certainty at this stage. However, Acceleron was barely changed.