William Collier: Yes. Okay. Good question. Maybe Mike Sofia, would you like to talk about 161 and 101, and I’ll come back with 729.
Michael Sofia: Sure. Thanks, Charlie, for the question. So when we look at our oral PD-L1 inhibitor AB-101, obviously we’re looking at safety as our first readout in the Phase Ia study. But we can also actually gain some insight on how this molecule is working and whether we anticipate efficacy when we’re looking at, so we have several abilities to look at target engagement and target occupancy. So from those studies, we’ll be able to see whether this molecule is actually engaging the target and producing some kind of target relevant biological readout from the immunology side. So that will give us some early hints on whether this molecule, it has the potential to show HBV clinical efficacy as we progress in the Phase Ib studies.
So we’ll get that in the SAD-MAD portion of the study pretty early. And so we’ll be able to say something about that by the end of the year. When you look at AB-161, our RNA stabilizer oral compound there, clearly this field has struggled with safety. So safety is going to be a big part of how we assess this very early on. Now as I’ve always mentioned, we’ve done in a very extensive preclinical safety assessment based on our previous knowledge that we gained on AB-452 and the peripheral neuropathy studies. And so we’ve done 60-day, 2 species toxicology studies — I mean 2 90-day, 2 species toxicology studies, to reaffirm our belief that this molecule has a safety profile that we feel confident in going forward in the clinic. But that early — obviously, Phase I studies where we’ll be looking at safety pretty clearly and paying clear attention to some of the signals for the peripheral neuropathy are going to be important to us.
Once that’s done, then obviously, we’ll run right into a Phase Ib study where we’ll be capturing the efficacy aspect of it, the biomarkers and specifically looking there at the antigen reduction in HBV DNA reduction in those parts of the Phase Ib study.
William Collier: And then on the 729 follow-up of these nine patients who are now off therapy. I just want to clarify, we now have seven patients remaining for follow-up. But I want to just clarify, but actually, — so far, only one patient has met the clinical criteria to restart therapy. There was one other patient who experienced what looked like some kind of increase in HBV DNA. So before that patient met any restart criteria, the physician and the patient decided to restart therapy. So out of the nine, we only have one that’s met the predefined protocol criteria for restarting therapy. So we remain really intrigued and interested in this data. We think it is a well worthwhile following up. We have some interest, obviously, from physicians and KOLs in continuing to track these patients.
We should point out that many of these patients now are multiple weeks into being off of therapy. And so I think as we’ve alluded to, we’ll track these patients and continue to report data as we progress through 2023.
Operator: Our next question comes from Thomas Yip with H.C. Wainright. Your line is open.
Thomas Yip: Good morning, everyone. Thomas asking a couple of questions for Ed. So first, a follow-up on the tale of the seven patients that remain off treatment in the 001 study. Can you tell us what is the range of how many weeks these patients have gone off treatment? And how frequently should we expect updates this year from these patients?
