Re: Hopefully a late day pop?
posted on
Apr 12, 2018 11:41PM
"On the other hand, this represents a competing approach to ours. Hence my question about how much time we truly have before someone might make great strides and steal our thunder?"
I don't see how either CRISPR-mediated gene editing or the the modified CRISPR gene activation approaches compete with a small molecule that selectively binds and inhibits to the second bromodomain of BET proteins. Even if all of apabetalone's beneficial effects are derived from BRD4 modulation (has not been shown), the best a CRISPR or modified CRISPR approach could do would be to repress BRD4 levels to achieve an analagous effect. But this would block both BD1 and BD2 mechanisms and not allow a selective BD2 inhibition approach like apabetalone. And if BET proteins other than BRD4 are also involved in mediating the effects of apabetalone (they probably are), then the CRISPR methods would likely not be able to hit multiple targets.
On a similar note, apabetalone modulates the expression of MANY genes. If one wanted to use CRISPR to mimic apabetalone's effects, what genes would you choose? There are so many that are modulated by apabetalone. Even if CRISPR eventually is used to hit multiple gene targets, we are looking at decade(s) before an approval of a therapy like that. Also, keep in mind that this approach in the Salk video still uses AAV viruses, which give rise to long-term expression (years?). Once you are infected with the AAV, you might have this in your cells for life. You think the FDA would want to approve a long term AAV approach as a standard of care for high-risk CVD patients (or renal patients, etc)? Not likely. Most likely the AAV/CRISPR strategies will be useful for treating diseases rare genetic diseases with minimal to no current treatment options.
It is much more likely that another company will bring a BET inhibitor to the clinic to compete with apabetalone rather than an AAV/CRISPR approach becoming a competitor. CRISPR in the clinic is still in its infancy. A long ways to go. Eight year lead (minimum) sounds about right in my opinion for a new BET inhibitor molecule entering Phase 1 to pass all the tests concluding with a Phase 3. And by that time, the apabetalone lightning will have struck and the thunder rolled, or the weather forecast was completely wrong.
BearDownAZ