Prana Biotech (PRAN) said on Thursday that after further analysis of a failed Alzheimer’s study, the company will likely move forward with lead drug candidate PBT2 in a larger clinical trial. PRAN climbed 24% on the announcement.
In March, Prana announced that the IMAGINE trial failed to meet its primary endpoint, a statistically significant reduction in beta-amyloid plaques in the brains of Alzheimer’s disease patients. The drug also failed to hit key secondary endpoints, most importantly, improving cognition and function. With Thursday’s release, the company is enthusiastic about a larger trial powered to demonstrate a cognitive benefit.
Prana says that a subset of patients in the IMAGINE trial that had baseline amyloid levels above the average in the trial (SUVR – standard uptake value ratio – of 2.5) demonstrated a significant decrease in amyloid burden that was not observed in patients on placebo or PBT2 that had a baseline SUVR of less than 2.5. The company also confirmed that brain volume (measured by MRI) in PBT2 treated patients was better preserved than patients on placebo. IMAGINE was a 42-patient
Just this week, Roche (RHHBY) revealed that a mid-stage trial of an amyloid-clearing antibody, crenezumab, failed to delay a decline in cognitive skills in mild-to-moderate Alzheimer’s patients. The Roche news follows failures of similar antibodies, Elan’s (ELN) bapineuzumab and Eli Lilly’s (LLY) solanezumab. The amyloid hypothesis suggests that buildup of amyloid plaques in the brain are the cause of the cognitive and functional decline in Alzheimer’s Disease. Though researchers continue to pursue the amyloid-clearing approach, the growing body of evidence seems to indicate that clearing amyloid simply doesn’t have the impact on cognitive outcomes that many once expected.
Subset analyses (or “data dredging”) are commonplace among small cash-strapped biotech companies that need to keep investor hope alive in order to keep the lights on, though rarely do they pan out in larger trials. Regardless, Prana simply doesn’t have the resources to run a sizable trial in the indication. Late-stage Alzheimer’s studies have traditionally been funded by pharmaceutical companies with deep pockets; the bapineuzumab phase 3 program is reported to have cost over $400 million. Prana had $39.17M in cash at April 7. For those betting on the latest from IMAGINE, expect dilution down the road.
