Q2 2023 Bioatla Inc Earnings Call

Participants

Bruce Mackle; IR; LifeSci Advisors, LLC

Jay Short; Chairman, CEO, & Cofounder; BioAtla, Inc.

Richard Waldron; CFO; BioAtla, Inc.

Eric Sievers; Chief Medical Officer; BioAtla, Inc.

Sheri Lydick; Chief Commercial Officer; BioAtla, Inc.

Brian Cheng; Analyst; JPMorgan Chase & Co.

Kaveri Pohlman; Analyst; BTIG

Arthur He; Analyst; HC Wainwright & Co.

Tony Buter; Analyst; EF Hutton

Reni Benjamin; Analyst; JMP Securities

Presentation

Operator

Greetings, and welcome to the BioAtla second-quarter 2023 earnings call. (Operator Instructions) As a reminder, this conference is being recorded.
It is now my pleasure to introduce your host, Mr. Bruce Mackle with LifeSci Advisors. Thank you, Bruce. You may begin.

Bruce Mackle

Thank you, operator, and good afternoon, everyone. With me today on the phone from BioAtla are Dr. Jay Short, Chairman, CEO and Co-Founder; and Richard Waldron, Chief Financial Officer. Following today's call, Dr. Eric Sievers, Chief Medical Officer; and Sheri Lydick, Chief Commercial Officer, will join Jay and Rick for a short Q&A.
Earlier this afternoon, BioAtla released financial results and a business update for the second quarter ended June 30, 2023. A copy of the press release and corporate presentation are available on the company's website.
Before we begin, I'd like to remind everyone that statements made during this conference call will include forward-looking statements including, but not limited to, statements regarding BioAtla's business plans and prospects, potential selective licensing, collaborations, and other strategic partnerships, whether its clinical trials will be potentially registrational, achievements of milestones, results, conduct, progress, and timing of its research and development programs and clinical trials, expectations with respect to enrollment and dosing in its clinical trials, plans and expectations regarding future data updates, clinical trials, regulatory meetings, and regulatory submissions, the potential regulatory approval path for its product candidates, expectations about the sufficiency of its cash and cash equivalents, and expected R&D and G&A expenses.
These statements are subject to various risks, assumptions and uncertainties. They can cause actual results to differ materially and are described in the filings made with the SEC, including the most quarterly report on Form 10-Q. You are cautioned not to place undue reliance on these forward-looking statements, which speak only as of today, August 1, 2023, and BioAtla disclaims any obligation to update such statements to reflect future information, events, or circumstances except as required by law.
With that, I'd like to turn the call over to Jay Short. Jay?

Jay Short

Thank you, Bruce, and thanks to everyone for joining us for our second-quarter 2023 BioAtla earnings call. BioAtla is the inventor and leader in the development of novel therapies using a proprietary conditionally active biologics, CABs platform with improved selectivity for attacking tumor cells while avoiding healthy cells, thereby addressing urgent unmet needs in oncology to improve patients' lives.
We made significant progress last year across our multiple ongoing Phase 2 trials for our two latest stage, first-in-class CAB-ADC product candidates, BA3011 and BA3021, targeting solid tumor types with high unmet medical needs. As we are now a little over halfway through 2023, we continue our positive trajectory and remain on track to achieve our recently guided milestones outlined on the first-quarter call in May.
We remain focused on further advancing the development of our innovative clinical programs, leveraging the broad applicability of our CAB technology across several clinical stage antibody types, including CAB-AXL and CAB-ROR2 ADCs, CAB-CTLA4 immuno-oncology naked antibody, and our first dual CAB bispecific EpCAM CD3 T cell engager. Additional details related to what I'm going to provide are available on our website as part of our updated company presentation that may be helpful to you.
We remain excited about our lead asset BA3011 for multiple indications. Previously, we shared the encouraging partial interim data on our BA3011 Phase 2, part one sarcoma study and our BA3011 Phase 2, part one non-small cell lung cancer study. We also shared additional insights of how we have applied the learnings from our differentiated safety data and exposure response analysis as well as our UPS-related FDA interactions to study more frequent dose intensity regimens more broadly across our AXL ADC and our ROR2 ADC programs.
The goal is selling more frequent dose intensity regimens across programs is to provide data to allow us to set study parameters that maximize the company's likelihood of success for our Phase 2 potentially registrational studies. A summary of our current dose regimens can be found in the updated corporate presentation on our website.
Let's now move to our clinical, operational, and financial updates for the second-quarter 2023. First, we are advancing BA3011 in our ongoing sarcoma Phase 2 studies, including a potentially registrational study in UPS. Without specific treatments approved for UPS, there's a significant commercial opportunity as a stand-alone indication. We have shown strong execution and promising results with continued anti-tumor activity, lack of disease progression, and a differentiated safety profile with BA3011 in UPS to date.
Based on these results, together with the continued differentiated safety profile and encouraging feedback from the FDA around the study design, last year, we initiated part two of the potentially registrational portion of the trial. The first 40 patients are being randomized one-to-one between the more frequent dose intensity regimens.
Following the first 40 patients, we plan to enroll an additional 40 patients at the selected dose to complete the study. The primary efficacy endpoint, ORR will be based on approximately 60 patients treated at the selected dosing regimen. As an update, we achieved first patient in and are actively enrolling patients.
In addition to UPS, we have completed enrollment of the Phase 2, part one leiomyosarcoma cohort using the 3Q4W dosing regimen and are on track with an anticipated data readout on 10 to 15 patients in the second half of this year. Further, the remaining bone sarcoma cohorts in Phase 2, part one are on track to finish enrolling in the second half of 2023.
With regards to safety profile across all sarcoma subtypes, there are no new safety signals to report. BA3011 continues to be generally well tolerated with the Phase 2 safety profile across all doses consistent with the profile we observed in Phase 1.
Regarding our BA3011 Phase 2 study in AXL-positive multi-refractory non-small cell lung cancer, we continue to be encouraged about the data from the Q2W dosing regimen, while we anticipate data from the more frequent dose intensive regimens. Currently, the standard treatment options in patients who progressed on immune checkpoint inhibitors have suboptimal overall response rates of approximately 10% to 20% and four-month PFS rates.
Part one of the Phase 2 study in non-small cell lung cancer is ongoing in AXL-positive patients who have previously experienced failure of either PD-1, PD-L1, EGFR, or ALK inhibitors and continues to enroll patients. Anticipated data for all dosing regimens assisting with the study design for the potentially registrational portion of the trial remains on track for the second half of this year.
We have submitted a meeting request to the FDA for potentially registrational BA3011 Phase 2, part two non-small cell lung cancer study design and anticipate feedback in the second half of this year and as a result remain on track to initiate the Phase 2, part two study in non-small cell lung cancer also in the second half of this year, maintaining our overall timeline for development of the non-small cell lung cancer indication.
We continue to believe BA3011 has the potential to become a significant commercial asset for BioAtla and an even greater importance, a first-in-class treatment for a significant number of patients who failed at least one prior line of therapy, thus addressing a significant unmet medical need.
Regarding the ongoing multi-center investigator-initiated IIT Phase 2 clinical trial in patients with platinum-resistant ovarian cancer, the trial is fully enrolled and remains on track for the interim data readout consisting of 10 patients in the second half of this year.
Now turning to our second CAB-ADC asset, BA3021, a CAB-ROR2 ADC, currently, BA3021 is a subject of Phase 2 trials in the treatment four different indications. We conducted a similar exposure-response analysis of ROR2-positive tumors to inform the more frequent dose-intensive regimen of 3Q4W in our Phase 2 ROR2-positive non-small cell lung cancer study.
Based on this analysis, which is a similar strategy to our UPS Phase 2 part 2 BA3011 study I mentioned earlier, we are screening and enrolling patients. Based on the activity to date, we believe that we remain on track to obtain data this year to permit clinical trial prioritization across our portfolio.
Regarding the melanoma Phase 2 trial in patients who have previously experienced failure of PD-1 therapy, we are continuing to screen patients with a validated IHC liquid biopsy assay. As we stated last quarter, we have successfully identified ROR2-positive tumors using the liquid biopsy assay, which is allowing us to enroll ROR2-positive patients. And we are on track to dose patients in the second half of this year.
In addition, our Phase 2 head and neck study is ongoing in patients who have previously experienced failure of PD-1 therapy alone or in combination with platinum therapy. Earlier this year, we announced achievement of first patient in for this study. Since that time, multiple patients have been dosed, and we continue to enroll patients.
Regarding the ongoing multi-center investigator-initiated Phase 2 clinical trial in patients with platinum resistant ovarian cancer, the trial is fully enrolled and remains on track for the interim data readout consisting of 10 patients in the second half of this year.
Now turning to our Phase 1/2 trial for our CAB-CTLA-4 antibody, BA3071, as a reminder, the Phase 1/2 trial is being conducted in tumors known to be responsive to CTLA-4 treatment. And we are continuing to evaluate safety and tolerability of BA3071 in monotherapy and in combination with nivolumab. The trial is progressing as planned.
Last quarter, we shared that we started treating patients in the fifth cohort at 350 milligrams or 5 mg/kg as monotherapy and in combination with 3 mg/kg nivolumab. As part of today's update, I'm happy to report that the DLT observation period was cleared for the fifth cohort, and no DLTs were reported. We are currently enrolling patients in the sixth cohort at 700 milligrams or 10 mg/kg as the monotherapy or in combination with 3 mg/kg of nivolumab and remain on track to our Phase 1 data readout anticipated the second half of this year.
We also remain on track to initiate BA371 (sic - BA3071) Phase 2 study also in the second half of this year. We believe there are significant unmet medical needs with sizable commercial opportunities across multiple tumor types where CTLA-4 can deliver efficacy with a manageable safety and tolerability profile that allows patients to stay on therapy for longer and thus achieve the full benefit of this important immunotherapy.
Next on to our potentially first-in-class dual CAB bispecific T cell engager antibody CAB-EpCAM and CAB-CD3 or BA3182, as mentioned during last quarter's call, we received FDA clearance of our IND for the treatment of advanced adenocarcinoma. We are now actively enrolling patients in this Phase 1 study with the full data readout remaining on track for next year.
Similar to our other three clinical-stage CAB assets, this antibody has shown significant promise in in vivo preclinical studies, demonstrating an over 100-fold improvement in therapeutic index relative to the non-CAB variance due to the combined selectivity of the dual CAB design. We believe that our dual CAB design has the potential to address the tremendous unmet need across several of the most common subtypes of adenocarcinoma, including colon, lung, breast, pancreas, and prostate.
Finally, we continue to pursue opportunities to share our progress with the medical and scientific communities with an additional two Trial in Progress abstracts, one for BA3011 and another for BA3021, which were accepted for poster presentations at the upcoming World Conference on Lung Cancer this September. This brings the total confirmed medical meeting presentation talent to 11 since the beginning of the year. Additional abstracts have been submitted for several upcoming meetings as well.
With that, I would now like to turn the call over to Rick to review the second-quarter 2023 financials. Rick?

Richard Waldron

Thank you, Jay. As of June 30, 2023, we had $168.7 million in cash and cash equivalents compared to $215.5 million as of December 31, 2022. We expect current cash and cash equivalents will be sufficient to fund planned operations, including all ongoing CAB product development programs into 2025. As a reminder, we control all CAB product market rights in the US, Europe, and Japan.
Our business strategy includes advancing commercial preparations in key global markets while exploring opportunities to extend our cash runway by generating upfront cash through the selective licensing of product rights in certain territories or collaborations with other biopharmaceutical companies that could also provide to us development milestones and royalties upon regulatory approval and commercialization and create additional value for stockholders.
For the second quarter ended June 30, 2023, we reported a net loss of $35.8 million compared to a net loss of $28.9 million in the same period of 2022. Research and development expenses were $31 million for the second quarter ended June 30, 2023, compared to $20.7 million for the same period in 2022. The increase of $10.3 million was primarily driven by our preclinical and clinical product development efforts. We expect our R&D expenses to remain variable from quarter to quarter and generally increase as we continue to invest in R&D activities to advance our product candidates and our clinical programs.
General and administrative expenses were $6.2 million for the quarter ended June 30, 2023, compared to $8.3 million for the same quarter in 2022. The $2.1 million change was attributable to a decrease in various administrative expenses for the 2023 period. We expect our G&A expenses to moderately increase to support development of our product candidates, advance our intellectual property portfolio, support focused pre-commercialization activities for our asset BA3011, and satisfy requirements as a public company.
Net cash used in operating activities for the six months ended June 30, 2023, was $46.7 million compared to net cash used in operating activities of $42.1 million for the same period in 2022. The increase in net cash used in operating activities for the first six months of 2023 is primarily due to an increase in research and development expenses related to our program development efforts as compared to the first six months of 2022.
And now, back to Jay.

Jay Short

Thank you, Rick. We are pleased with the progress we have made to date and cumulative results that continue to support both the preliminary efficacy and safety from our differentiated proprietary CAB platform. We are encouraged with the compelling clinical profile that is emerging in treatment refractory UPS and non-small cell lung cancer and are eager to start evaluating data from our Phase 2 studies with the addition of the more frequent dose-intensive regimens.
We're also excited by the continued clinical execution of our other promising CAB assets, in particular, our BA3071 CAB-CTLA-4 clearing the fifth cohort with no DLTs observed and are well positioned to reach several value-creating milestones and key inflection points by year end. BioAtla remains confident about the future with the goal of pursuing indications of high unmet medical needs that we feel will have significant impact for patients and our shareholders worldwide.
With that, we will turn it back to the operator to take your questions.

Question and Answer Session

Operator

(Operator Instructions) Kelly Shi, Jefferies.

Hi, this is Dave on from Jefferies. Thank you for taking our questions. I have a question on the request that you submitted to FDA. Can you talk a little bit more what kind of data have you provided to do the FDA? And does it include enough data to make a decision on RP2D?

Jay Short

Yeah. I mean, I think what we've really approached the FDA with is questions related to a study design and basically both with respect to whether it's a randomized trial, single-arm trial. And we provided a basic update of things that we have to date.
And maybe, Eric, you might want to add a little bit more on that.

Eric Sievers

Sure. Your question was about whether we've provided data regarding a recommended Phase 2 dose, I believe. And presently, we've submitted questions to the agency, just as Jay had mentioned, about the overall study design, randomization, on some of those features. We anticipate preparing more information regarding our dosing regimens in the briefing program.

Right. And one more thing, how many our patient data do you expect to include in the follow up? And do you have any internal model to move forward for ORR or PFS?

Jay Short

Eric, you want to start with that one?

Eric Sievers

Sure. We are evaluating patient as shown in our corporate deck at multiple dose levels, including more dose-intensive regimens. And I anticipate we'll have a full-some analysis of those data by the end of the year that we can provide to the agency as a part of the Project Optimus.

Jay Short

And I would add that we're testing basically three different doses, the every-other-week and then the 2Q3W as well as the 3Q4W. And so we'll have a little bit more data on the Q2W, but we believe we'll have sufficient data for all of the doses for our go-forward decision, how we're going to approach it.

Great. Thank you for taking our question.

Operator

Brian Cheng, JP Morgan.

Brian Cheng

Hey, guys. Thanks for taking my questions this morning or this afternoon. Just a couple from us, maybe first on 3021, given the number of potential opportunities here for the molecule, how do you think about the factors to consider when making a prioritization decision? What is your latest thoughts on collaboration or partnership that could potentially build in this consideration?

Jay Short

Yeah. When we're making these kinds of decisions, Brian, I think we're going to be looking across the entire portfolio. We have to weigh the AXL indications, the fact that we're in the lung AXL and also in ROR2 lung. How many lung indications should we take forward at the same time?
We'll be evaluating that, and that's going to be related to data and also where things are safety wise. I think we're across the board feeling very comfortable across all the indications. So I think -- I know personally, I'm very interested to see how the head and neck reads out. We're still accumulating data, likewise in lung, and of course, on both at the AXL and ROR2, we're seeing -- we expect to see -- on track to see ovarian cancer data as well.
And by the way, just as a footnote at the time of -- right up on the script, we hadn't dosed the melanoma patient yet, but at least we crossed that line today. And so I think that's truly going, and that's going to give us a nice picture there as well, which we expected, but it's nice to see it maybe a little ahead.
So overall, I'd say we have more indications and more drug opportunities that most companies have. So you've got an opportunity to really pick the best ones to advance. And that also gives us some freedom for partnering as well.
And I don't know, that's maybe a high-level response. And maybe I don't know, Sheri, you want to add anything else to it, but don't feel obligated.

Sheri Lydick

No, I think you covered it, Jay. Thank you.

Brian Cheng

Yeah. Maybe just one more on 3071, any color on clinical activity so far with the fifth cohort dosing? And just how should we think about the potential indications for the Phase 2 dose-expansion cohort?

Jay Short

Yeah. I mean, safety wise, we're very happy with that. We're also very encouraged without getting into any specifics, but with the data readouts that we're seeing already. And so I would say that as we said in the script, we're excited about that asset, and we continue to be.
And I think you'll recall that we're testing this across eight different indications, all known to have some responsiveness to CTLA-4. And so we've done a fair bit of analysis on which ones we are likely to take forward. But I think we're going to see how the next cohort reads out and tighten that view. But I think at this point, I certainly wouldn't be ruling out any indications.
However, there will be some, I think, that have a great opportunity. And I would prefer not to list them now because this is an evolving asset. And I really like the data we're seeing with the combination with PD-1 at 3 mg/kg and clearly the 5 mg/kg. And we already have dosed the patients after at this next level, so it's ongoing.

Brian Cheng

Great. Thanks for taking my question.

Jay Short

I should add, Brian, that one nice thing about CTLA-4 is that it also opens up the door for future combination therapies and just like in analogous way that PD-1 has done with so many different other therapies. So one can't help but sit back and think about those possibilities in addition to just combining with PD-1.

Operator

Kaveri Pohlman, BTIG.

Kaveri Pohlman

Yeah. Good evening, and thanks (technical difficulty) Phase 2 trial, it's a relatively small sample size. Any color on when do you think you'll be able to complete the frequent dosing study? And will you be reporting efficacy data from these cohorts after a selection of the right schedule or that won't be allowed as some patients will be part of the pivotal trial?

Jay Short

Well, if we're talking about lung, we do anticipate -- well, we'll have the data, enough data for the more frequent dosing to make our plan for going forward into a registrational study this half of this year. We are and have identified a medical meeting where we intend to provide an update on our data, both for the every-other-week dosing as well as in the more frequent dosing.
We're going to report on that meeting after we formally get accepted at the at that meeting. But we believe that's on track for communication this year. That's with the AXL in lung. The UPS, of course, is the registrational or potentially registrational now, and again, we'll not be reporting on that until later next year once we get further down the line on that.
And then the ovarian studies, we intend to report out on those both for the AXL ROR2. And we're certainly hopeful that we'll have sufficient data from the ROR2 asset to allow us to affect the prioritization across our portfolio, both from the standpoint of what we want to take forward and what we might want to partner, et cetera. I'm not sure that we're going to report out efficacy data on ROR2 this year, but we'll certainly have some sense of the prioritization.
And of course, CTLA-4, I think also we're going to be -- we'll be giving updates, routine updates on as we progress through Phase 1 about, I think, as we'll also guide a little bit on where we're going ahead with the Phase 2 study as well. The actual readout on that is probably -- most of our plan, as we've reported earlier in the year, is to align with medical meetings for our readout. But we've tried to bring in as many of those as we can into this year.

Kaveri Pohlman

Got it. That's very helpful. And then I believe for ovarian cancer results, you mentioned that you have completed the enrollment. But can you tell us how long these patients have been on treatment? And will you be able to provide any results on durability?

Jay Short

Well, these have started some time ago, and I'll maybe allow Eric to give better feedback on the timeline. But I'd just remind everyone, these are IIT studies so the actual -- we're waiting on the data ourselves. So we're hope -- we know it is not too far off in the future. We've been told by our Phase 2 studies; we know they're fully enrolled. So we should have a nice snapshot.
But Eric, maybe you want to get a sense when things started, keeping in mind that all the patients have come on board at different times. So it's hard to give a specific number. But Eric, you want to add some more color to it?

Eric Sievers

Jay, I think you've characterized it really well on. We started working with the Canadian clinical trials group back in 2020 about this. Then we had a mature protocol and started enrolling patients at different times in the two different protocols -- I mean, the two different regimens, one for the ROR2 asset and the other for AXL. We are looking forward to seeing these data as well.

Jay Short

Well, I think we're going to get some insight on durability. Obviously, the latter patients in that study will have a little less than the earlier ones, but that's the way it works.

Kaveri Pohlman

Got it. And maybe last one, besides exploring the dosing schedule, do you also plan to continue to explore AXL expression score for each tumor type to confirm the patient population that responds best to the treatment? And any changes you expect or need to make in terms of your companion diagnostic tests?

Jay Short

I think the companion diagnostics path forward was in good shape. I would just say, though, we are -- I think we reported out earlier in the year that we had at least one PR at the 1% TmPS score level in lung. So we are exploring a bit further and without getting into too many details at this point. But yes, that's certainly on our mind, and we're evaluating things.

Kaveri Pohlman

Excellent. Thanks for taking my questions.

Operator

Arthur He, HC Wainwright.

Arthur He

Hi. Good afternoon, Jay, Rick, Eric, and Sheri. Thanks for taking my questions. I had a -- as for the on the 3071 data update, so could you just tell us at the current the 5 mg/kilo in combo, what's the average cycles of the 3071 being dosed?

Jay Short

It can be very low because I think we reported out that we were just dosing down in our May timeframe, something like that, and the May, June area. I think also at some of the conferences, we may have mentioned in June. So you can only expect it to be a couple -- a few months. But I think in general, we're encouraged with what we're seeing.

Arthur He

Okay. Thanks for that. And I just --

Jay Short

By the way, Arthur, I should add, though, but we have earlier dose levels that just happened to be earlier. Several of those have gone on for quite some time, well over the three to four cycles that have normally attainable.

Arthur He

I see. I see. Yes. And just for the 10 mg/kilo, is it still in the monotherapy dosing stage, or it's already reached the combo dosing?

Jay Short

I think it's -- we don't have a precise -- I know one has made it, but I don't have much more information, and I don't know the status, but -- so that's about all I'm going to give right now. Let's just see how it plays out here.

Richard Waldron

Sure. No worries. And my second question is on the EpCAM program. So congrats on the progress. And so for the data update we expect for the next year, could you first give some update on the enrollment status for the study? And regarding the updated -- or what kind of dataset we could expect? Thank you.

Jay Short

Well, there are elements active across many centers, which we had to roll out across. And so we're happy that that's rolling, and I think it fits our timeline. And we should be able to -- I don't know when we're going to get the first update on that. I would certainly be -- we're just basically would be a little bit similar to how we're handling CTLA-4, but I don't think we would give too much insight on the early doses because they're probably less relevant.
But as we start to march up toward, I would say, EC50, where we start seeing efficacy expectations, and I think looking at the data more (technical difficulty). But clearly, we're on track for next year as everything looks right now, and that's an exciting asset, no question.

Arthur He

Awesome. Thank you. Thank you for taking my question, and congrats on the progress.

Jay Short

Thank you.

Operator

Tony Buter, EF Hutton.

Tony Buter

Thanks very much. Jay, two questions on 3071, please. One is, at 700 mg Q3W, do you -- will you have enough durability in the three to six patients that actually tells you that you need to move forward with whatever two-ish or three-ish cohorts you wish to move forward with? That's question one.
Number two is, though you said you've done a lot of work on each of those seven cohorts, the notion that any one may be better than another, I guess would you -- are you limited to two is really what I'm saying, which is what you state in your corporate presentation? Thank you.

Jay Short

What do you mean limited to two? Two combinations?

Tony Buter

Selected to two for potential Phase 2 dose-expansion framework (multiple speakers) --

Jay Short

Oh, yeah. No, no, no --

Tony Buter

For example, in RCC or whatever. Okay. Yeah.

Jay Short

Yeah. I think we have a a lively discussion around that exact point, Tony. I'm kind of glad you asked it. I think the reason we set up beyond that two was because we're confident we're doing two. I don't mean that -- and I don't mean that to say we're not going to -- couldn't do more than two. But for now, I say two looks pretty solid, and there could be a decent argument to consider more.
I think with respect to what dose we end up with and durability, I think that remains to be seen, but one's got to love the fact that you're at 5 mg/kg with a plus 3 mg/kg on the PD-1 side, and you haven't got a DLT. And now, we're able to at least dose the people. And we'll just see where patients and where it goes at the 10 mg/kg with 3 mg/kg on PD-1.
This is close to uncharted territory. Adjust for PK and adjust for a few other things, we really like where this asset is going. And I think it's going to -- I'm hopeful it will highlight what I think is a powerful advantage of CAB technology.

Tony Buter

Within that statement -- and thank you for -- with the two. But the real notion is, is there added -- is there any reason to assume even though you may for the sake of discussion, we don't know. And notion to say that 2x 3071 dose that 350 mg/kg to 700 mg/kg, let's say, really gives you added efficacy despite the fact that there's side-effect profile?

Jay Short

Well, I think we know from other -- yeah, I think you know from past studies with other CTLA-4s, if you could -- two things: if you could potentially increase the dose or, and/or if you can keep patients on more cycles, you do translate to better outcomes if you can manage the safety. And I think there's a fair bit of literature around that.
That's not quite as much the case with PD-1. And with CTLA-4, there is support for that, and that actually was the original objective. Could we, number one, get to a higher dose in combination with PD-1? That's one question. The second question was, could we get beyond three to four cycles in the combination therapy with CTLA-4 and PD-1. And the third question is, could we do both?
And that's what we're on the precipice of answering, and I think we've already answered a portion of it with the 5 mg plus 3 mg that we cleared. And of course, we'd like to see a readout for a few more months on. So all of these things going forward here are additive, but we're at a point in the right timeframe to look at it. And I think we're going to have a great -- encouraging answer, I'm hopeful, later this year.

Tony Buter

Been very helpful. Thanks so much.

Operator

Reni Benjamin, JMP Securities.

Reni Benjamin

Hey, guys. Thanks for taking the questions. You mentioned that you identified ROR2-positive tumors using liquid biopsy. Can you talk a little bit about how many patients were identified? And what does this tell you about the proportion of ROR2 patients in the real world versus epidemiological studies and the numbers we get from that?

Jay Short

Yeah, it's kind of interesting. In melanoma, you'll recall that we saw approximately 7% positivity rate for ROR2 in melanoma using an IHC assay, immunohistochemical assay. As we transition to the liquid biopsy, we haven't given a definitive number, but I can tell you it's certainly double-digit positivity rates.
So it's clear that the liquid biopsy, because we've done a lot of validation around this assay, has -- seems to be more sensitive, being able to pick up patients that ROR2 positive, but at a lower and probably a more sensitive level. So we're seeing more patients. So that's an advantage that goes beyond the fact that it's much easier to perform that assay.
So I think the lesson here is that every assay has a certain sensitivity. And of course, the only patients that we had studied -- we had one patient in -- evaluable patient in Phase 1. We had one valuable patient come across in the Phase 2 study, partly only one and one that were evaluable because of the low positivity rate.
Well, if you can start to move the positivity rate up, then you're going to get a lot more patients wanting to come on board to do the study. It's a lot easier to take a blood draw than it is to go and get a tumor biopsy from the patient. The question remaining is, what is that threshold that allows you to see that activity? But with ADCs, there's a lot of history say that there could be a wide range of reaction.
And so like in our head and neck, we saw something in the teens. It was TmPS score in the teens that we saw a PR right our first dose. So long story short, this liquid biopsy is allowing us to see a larger number of patients from a positivity standpoint.
The next question we're hoping to answer is that do we maintain a strong response rate in this group? And we should be able to answer that in the near future.

Reni Benjamin

Got it. And I think I've asked you this before, but now that you're dosing the melanoma patients, do you kind of wait to see how this reads out before you're testing the other indications with this liquid biopsy? Or do you kind of -- I think in the past you may have said that with these other indications, you have quite a robust ROR2 expression. And so we don't really need to use the assay.

Jay Short

Well, we -- yeah, I think rolling it out -- we definitely are working at the research level to make sure we have it covered in these other areas, including AXL, if we needed. However, to roll it out with the expense that you might want to put behind a companion or need to put behind the companion diagnostic, no.
We wouldn't do that until we got more confirmation beyond what we have at the moment. Because we're -- keep in mind, we're also wanting to manage our capital, and we're forecasting to get into 2025. And that means you've got to be prudent on how we do things.

Reni Benjamin

Got it. One final one for me, the Phase 2 investigator-sponsored ovarian study in platinum-resistant ovarian cancer, you're getting the 10 patients. What kind of data do you need to see?
Or what would like to hit that so that, I don't know, it would be kind of brought back in-house and developed under a corporate IND versus giving it as an IST? Or is this something -- is this an indication that you would really just like to be seen -- developed by somebody else, even if it's an academic partner?

Jay Short

Well, we've had corporate, we've had companies ask us about the ovarian cancer. So there's interest out there. And what the exact cutoff is, is interesting because it depends on how that whole field is emerging a little bit. But I think the bar is fairly low at the moment in terms of what you need to see to advance this.
But I think how we'll take that forward is going to be linked to the data. What that exact cutoff will be -- is still being debated. But beyond that, it's hard to answer at this particular second. We have our own thoughts.
I mean, I would say I'll just throw out, I think 20% still quite viable if you're seeing responses, keep in mind, though, a lot of these drugs get approved on PFS and not ORR. So I just -- we have to keep all -- as well as overall survival. So we have to keep all of these various aspects in mind.
But we'll keep an eye on it, and we will look at it as an upside. And it's a study that we wouldn't have been able to fund ourselves at that time, and it's in combination with PD-L1. So it's going to be an interesting readout one way or the other.

Reni Benjamin

Got it. Thanks for taking the questions.

Operator

Thank you. We have reached the end of our question-and-answer session. And with that, I would like to turn the floor back over to CEO, Dr. Jay Short for closing comments.

Jay Short

Well, I just appreciate everyone's attendance, and we've got a very active fall here coming up. And we're really looking forward to speaking with everyone at meetings and other venues as we go forward. But thank you for your attention today.

Operator

Thank you. This concludes today's teleconference. You may disconnect your lines at this time. Thank you for you participation.