Thread by @BertrandBio

$LYS +32% in Paris trading this morning, with a press release worded like the "highly stat. sig." mean change in CSF HS concentration was saying it all, but unfortunately that's not really the case.
Directionally the variation seems OK, but 1/ p-values don't provide any magnitude

of an effect by themselves (unless you reverse some other data), and 2/ one also needs to take into account where the bar is ideally.
On point #1, Abeona already provided data with "highly stat. sig." (assuming this measn "p-val in the range of ~0.001 vs baseline") according to

rapid calculations (60-80% reductions obsverved across cohorts with ABO-102 at 6-12mo) & data/charts available on HS in CSF of MPS IIIa patients. However, coming to point #2, when one looks at the HS in CSF in MPS IIIa vs control, one would ideally need to see reductions >= ~90%.

Even with the good data of ABO-102, they haven't seen much impact on the course of the disease in most of the patients, except perhaps for 3 subjects at the highest dose in cohort 3 (~75% median reduction from baseline in n=8/7 at 6-12mo respectively), though the follow-up might

still be a bit short to really know. So the bar is very high for the primary endpoint of $LYS trial (change in development quotient vs baseline), & the fact that $LYS didn't provide any numerical data on the reductions in HS in CSF but only "highly stat. sig." reductions doesn't

really help us much for now vs a potential hit on primary endpoint. These HS in CSF numbers will be out for sure mid-February for $LYS $SRPT LBA presentation at WorldSymposium 2021. (Abeona also has an update of ABO-102 Transpher A at the same event), so hopefully more clarity

after the event. Last point, $LYS LYS-SAF102 is still in clinical hold in the US after "observations in some patients of localized findings on MRI images at the intracerebral injection sites, the localized nature of the findings suggesting a pot. connection to the delivery" (see

also $VYGR $NBIX clinical hold with "observation of MRI abnormalities", which like LYS-SAF102 is administered directly into the brain via canula).