Q32 Bio Inc. Common Stock Wells Fargo 21st Annual Healthcare Conference

Good afternoon, everybody. Thanks for joining our next session. My name is Derek Archila. I am one of the senior biotech analysts here at Wells Fargo, and I am very happy to have Q32 Bio for our next fireside. So from the company, we have Jodie Morrison, CEO, Shelia Violette, CSO, and Lee Kalowski, CFO. Thanks to you for joining us.

Thanks for having us. We appreciate it.

Maybe Jodi, starting with you, if you want to just give us at a high level what you guys are working on, state of the business. You had some data, positive data- Yeah earlier in the year.

So walk us through what transpired, and we can get into the more granular questions after.

Absolutely. A big year for us, obviously, with the readout from the Part B of our SIGNAL-AA program. An exciting turn for us, I think, as that data matured, and we were able to really show that we're in the JAK class, as far as efficacy goes. That was what we were looking to accomplish with the program, and we certainly did, both on the mITT and the ITT data, now showing that 30% and 40% SALT20. Really exciting for the company and for patients. We're excited to move to the registration program next for alopecia areata. That'll be the next step, and then beyond that, we're internally starting to think about what indications we can target next with lots of opportunity, both in the derm space and non-derm adjacencies as well.

Got it. Maybe just looking at the data from Part B and maybe talk us through the two populations that you looked at, the mITT.

Modified intent to treat, and the intent to treat populations. I guess what will you be really pointing to regulators in terms of the data and the path forward here?

Yeah. The good news for us, both data sets look really good, so we're very pleased with that. We thought it was really important to put the ITT data out. We had a pre-specified mITT population defined in our statistical analysis plan, so that included, in the end, two cuts that were applied to the program. The first was patients who had not received at least 50% of the doses. In a 36-week dosing regimen, they needed to have received at least 18 weeks. That was five of the patients that were removed fell into that category, including two that actually didn't even get past a couple doses. I think one had transportation issues, and the other had a needle phobia that hadn't been disclosed to the treating physician in a subq trial, so that was unfortunate.

We had three others for various reasons, mostly moving states, moving sites. I think one patient that went to jail, that was a first one for me.

Wanted to stay in, was actually a responder, but for reasons you can imagine, we could not keep dosing them. We lost that patient. Then we had another cut that got applied for unstable disease defined in the SAP as more than a 25% worsening of disease in the early part of the program, really representing that these patients needed to be stable under the criteria of inclusion, exclusion. Those three cases, two of them were patients at a single site that were transfer patients to the site that did not come with records on their stability. They should have provided those. The physician took patient report for that stability, and likely they were in a hair loss kind of contingency or period of time where they lost their hair. Unfortunately, those two were not appropriately eligible for the trial.

The third was actually a patient who had a medical history of NASH, reported that they had come off their NASH sort of diet that kept their disease in check, and in tandem with the worsening of NASH for a period of time, they lost their hair, which can happen during NASH. Those were the three that were cut for that.

Understood. I guess as you think about going forward into other trials, how do you control for some of these variables and ultimately- Yeah I guess the question being, how translatable, which population is probably more representative of what we would see in the phase III trial?

Yeah, I think ultimately what happens is in small studies, you apply these criteria because one patient can really throw your data set. In a large phase III trial, we are not as concerned about that, but there are some learnings. So if we think about the patients with unstable disease, we are obviously going to require that there is a paper trail of their stability provided. As part of our central review, we will do confirmation steps of that moving forward for diagnosis and stability of data. So that is manageable. I think needle phobia is an obvious question that they need to ask.

We will have more sites in this program, so that will allow us to sort of address patients who move locations when you have other, if you cover more of the states in the U.S., if a patient moves from one state to another, you may have optionality of another site for that patient. So there are ways we will address that within the program, but expectations are you would lose some patients to things like that.