Ra falls on interim Phase II PNH data

Ra Pharmaceuticals Inc. (NASDAQ:RARX) lost $5.31 (37%) to $8.92 on Monday after reporting mixed data from a Phase II trial of subcutaneous RA101495 to treat paroxysmal nocturnal hemoglobinuria (PNH).

Ra said RA101495 met the primary endpoint of reducing lactate dehydrogenase (LDH) levels from baseline to the mean of weeks 6-12 in a cohort of 10 Soliris eculizumab-naïve patients (p=0.002). However, in a cohort of patients who had switched from Soliris to RA101495, seven of 11 transfusion-dependent patients experienced breakthrough hemolysis and reverted back to Soliris. Ra said all five transfusion-independent patients in the switch cohort successfully switched to RA101495 as indicated by stable LDH levels and no episodes of breakthrough hemolysis...