BioAtla, Inc. (NASDAQ:BCAB) Q3 2022 Earnings Conference Call November 3, 2022 4:30 PM ET
Company Participants
Bruce Mackle – Investor Relations
Jay Short – Chairman, Chief Executive Officer and Co-Founder
Scott Smith – President
Philippe Martin – Chief, Clinical Development and Operations
Sheri Lydick – Senior Vice President, Commercial Strategy
Richard Waldron – Chief Financial Officer
Conference Call Participants
Brian Cheng – JPMorgan
Kelly Shi – Jefferies
Tony Butler – ROTH Capital
Arthur He – H.C. Wainwright
Reni Benjamin – JMP Securities
Operator
Good day and welcome to the BioAtla Third Quarter 2022 Earnings Conference Call – pardon me, BioAtla. [Operator Instructions] I would now like to turn the conference over to Bruce Mackle from LifeSci Advisors. Please go ahead.
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; Scott Smith, President; Philippe Martin, Chief of Clinical Development and Operations; Sheri Lydick, Senior Vice President, Commercial Strategy; and Richard Waldron, Chief Financial Officer. Earlier this afternoon, BioAtla released financial results and a business update for the quarter ended September 30, 2022. A copy of the press release is 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 our clinical trials will be potentially registrational, results, conduct, progress and timing of our research and development programs and clinical trials; expectations with respect to enrollment and dosing in our clinical trials, plans regarding future data updates, clinical trials, regulatory meetings and regulatory submissions, the potential regulatory approval path for our product candidates; expectations about the sufficiency of our cash and cash equivalents and expected R&D and G&A expenses. These statements are subject to various risks, assumptions and uncertainties that can cause actual results to differ materially and are described in the filings made with the SEC, including the most recent 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, November 3, 2022, 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. Thanks to everyone for joining us for our third quarter 2022 BioAtla earnings call. We continued the positive trajectory for advancing the development of our innovative clinical and preclinical programs enabled by the broad applicability of BioAtla’s CAB technology. The third quarter was marked by continued strong execution with promising results across our five ongoing Phase 2 trials for our two latest-stage CAB-ADC product candidates, BA3011 and BA3021 across multiple solid tumor types for these first-in-class therapeutic candidates.
Additionally, we are excited with the continued anti-tumor activity and lack of disease progression, along with multiple partial responses. As we continue to enroll additional patients in our BA3011 Phase 2 non-small cell lung cancer study as well as recent feedback from the FDA from our proposed path forward for our BA3011 Phase 2 sarcoma study. But before I go any further, I’d like to remind everyone that additional details related to what we are going to present are available on our website as part of our updated company presentation that may be helpful to you. We previously shared interim data on our BA3011 Phase 2 sarcoma study and our BA3011 Phase 2 non-small cell lung cancer study. And we now look forward to providing additional insights on both.
Further, on today’s call, we will discuss additional updates for our other clinical programs. Our Phase 2 BA3021 studies continue to progress, and we anticipate enrollment completion of up to 20 patients in our non-small cell lung cancer study by year-end for reporting in January. Our validated liquid biopsy assay in the melanoma studies being implemented using our assay before year-end. In addition, our head and neck study is ongoing, and we anticipate dosing multiple patients by year end. Our Phase 1/2 basket trial for our CAB-CTLA-4 antibody, BA3071 is progressing nicely with the first 2 cohorts completed and the third cohort expected by year-end.
We also received encouraging pre-IND feedback from the FDA for our dual CAB bispecific T-cell engager antibody, EpCAM CD3 or BA3182 and remain on track for an IND submission of the fourth quarter of this year. Additionally, we remain on track with IND submissions for up to two next-generation CAB candidates next year. We are pleased with our cumulative results that continue to support both the preliminary efficacy and safety from our differentiated proprietary CAB platform thus far in 2022, and we are well poised to continue with strong execution. We have several additional upcoming catalysts as well as important results to be covered in today’s discussion, including exciting updates from our Phase 2 sarcoma study as well as updates from our Phase 2 non-small cell lung cancer study with our lead asset, BA3011.
With that, I would now like to turn the call over to Philippe for additional details. Philippe?
Philippe Martin
Thank you, Jay, and good afternoon, everyone. I would like to start by providing an update on our Phase 2 study in non-small cell lung cancer with our CAB-AXL-ADC BA3011. As a reminder, part 1, our Phase 2 study in non-small cell lung cancer is ongoing in AXL-positive patients who have previously experienced failure of PD-1, EGFR or ALK inhibitor therapies. As of October, we have enrolled 24 patients of these patients, 14 are efficacy variable. These patients had failed on average three prior lines of systemic therapies, 13 patients had failed a PD -1 and 1 at failed EGFR inhibitors. These 14 patients are composed of 12 non-squamous and 2 squamous cell carcinoma patients.
Regarding non-squamous patients, 8 of 12 were administered BA 3011 and 4 of 12 received BA3011 in combination with a PD-1 inhibitor nivolumab. In non-squamous patients, we have observed to date 4 partial responses or PRs in the monotherapy group, representing an objective response rate or ORR of 50%. In PD-1 failure patients, the ORR in non-squamous patients is 57%. In the combination group, we have observed 1 complete response, or CR, for an ORR of 25%. These observations remain consistent with the preliminary data reported last quarter and confirms the efficacy signal observed in Phase 1. Of the two evaluable squamous cell carcinoma patients, no new patients were enrolled this quarter, and we have not yet observed a response in this subtype.
All patients enrolled were AXL-positive with a GNPS of 1% or more. The rate of AXL positivity in the non-small cell lung cancer population continues to be high. We estimate it to be approximately 35% for the non-squamous population and approximately 30% for the squamous population based on over 200 non-small cell lung cancer tumor sample listed so far for AXL expression. As of the latest safety data cut, the safety and tolerability profile from the Phase 2 non-small cell lung cancer study continues to be differentiated from other MMAE ADCs in monotherapy and in combination with nivolumab. No new signals have been identified from Phase 1, no treatment-related deaths and few grade 3, 4 AEs were reported.
To put this data into perspective, and notwithstanding the relatively small sample size of our data set, the preliminary efficacy observed in this study and in particular, that observed for the BA3011 monotherapy non-squamous group is highly competitive in this PD-1 refractory population and supportive of moving forward to the potentially registrational part of this study. As of data cutoff, we have enrolled 24 patients, which will allow us to perform an interim analysis by year-end. In the meantime, we continue to enroll patient in part 1 to help us better define which population and which treatment cohort or cohorts, we will be advancing to the potentially registrational part of the study.
Moving on to sarcoma. Previously, we presented interim data, both our Phase 1 and ongoing part 1 of the Phase 2 trial of BA3011. In part 1, we found that UPS and osteosarcoma subtypes responded to BA3011, which provided the rationale for moving forward into part 2, of the study based on predefined internal go-no-go criteria of either at least 1 partial response, a complete response for subtype or progression-free or PFS rate of at least 40% at 3-month. During our call last quarter, we shared data from additional cohorts where we observed the PFS rate of 60% in liposarcoma, a PFS rate of 50% in synovial sarcoma and a PFS rate of 67% in osteosarcoma. All three subtypes exceeded our predefined go criteria to Part 2 of Phase 2. To date, we continue to see similar or slightly improved PFS rate in all three sarcoma subtypes and are very encouraged that all three subtypes continue to meet our predefined go criteria to advance into part 2 of the Phase 2 study.
With regard to the safety profile across sarcoma subtypes, BA3011 continues to be generally well tolerated with a Phase 2 safety profile consistent with the profile observed in Phase 1. As communicated previously, we had asked FDA for written feedback on our proposed registrational plans in UPS. Written feedback was received in October, and we are pleased with the FDA response to the proposed study design. In particular, the agency was not opposed to the selection of objective response rate or as a primary endpoint in this population with initially proceeding with a total sample size of 80 patients and had minor comments regarding our inclusion/exclusion criteria.
FDA was also supportive of including a more intensive dosing arm as part of this study. Based on this written feedback from the agency and the compelling profile observed for BA3011, in this population, we believe we have a path forward to advance BA3011 toward registration in UPS. We are currently finalizing the protocol following the agency’s feedback and plan to start those inflation by the end of this year. Additionally, we plan on moving forward with additional sarcoma subtypes as part of a label expansion strategy following BA3011 approval in UPS.
I’d like to thank you for your attention, and Sheri will now highlight the significant unmet medical need and commercial opportunity in UPS and non-small cell lung cancer. Sheri?
Sheri Lydick
Thank you, Philippe and good afternoon everyone. With the data observed today in our Phase 2 sarcoma study, the FDA guidance received and the high unmet medical need and undifferentiated pleomorphic sarcoma, or UPS, we are excited to move quickly in pursuit of our leading indication for BA3011. UPS is one of the largest sarcoma subtypes, representing nearly 15% of all soft tissue sarcoma. It is also one of the most aggressive subtypes with one of the highest recurrence rates. There are currently no FDA treatment specifically approved to treat UPS and patients tend to progress very rapidly.
In addition, AXL positivity rate in UPS is quite high at around 80%, and we estimate there are approximately 3,000 to 4,000 AXL-positive addressable UPS patients per year in the U.S. alone. Adding in Europe and Rest of World, the number of addressable UPS patients who could potentially benefit from BA3011 exceeds 10,000 per year, which we estimate to be a worldwide commercial opportunity of approximately $750 million at peak. As such, UPS represents a solid initial indication for BioAtla as we seek to transition into a commercial stage biotech company. Additionally, based on data observed in other sarcoma subtypes, there is an opportunity to expand our label and footprint to include osteosarcoma, liposarcoma, synovial sarcoma and perhaps other sarcoma subtypes.
Ultimately, BA3011 has the potential to treat 25,000 plus sarcoma patients per year and generate up to $2 billion in revenue worldwide in this area of very high unmet medical need. Furthermore, we continue to be enthusiastic by the responses we’re observing with BA3011 in multi refractory non-small cell lung cancer. There are limited treatment options for these patients who progress on immune checkpoint inhibitors and available treatments in the second line and beyond setting have suboptimal overall objective response rates of approximately 10% to 20%.
With respect to market size, a significant proportion of non-small cell lung patients express AXL, and we estimate that there are approximately 40,000 to 50,000 AXL-positive addressable patients per year in the U.S. and over 100,000 per year worldwide. This second line plus indication has the potential to add approximately $2.5 billion to $3 billion in worldwide revenue at peak. The fact that we continue to see anti-tumor activity in non-small cell lung as we enroll more patients is very encouraging. And based on preliminary interim observations, we believe BA3011 will be highly commercially relevant with an ORR well above current ORRs observed in a multi-refractory patient population.
Taken together, sarcoma and non-small cell lung cancer, we believe BA3011 has the potential to become a significant commercial asset for BioAtla across multiple solid tumor types. Of even greater importance is that BA3011 has the potential to be a best-in-class treatment for a significant number of patients who fail multiple lines of therapy, thus filling a significant unmet medical need.
Now I would like to turn the call over to Scott Smith, President of BioAtla, to provide an overview and updates to our ongoing clinical programs. Scott?
Scott Smith
Thank you, Sheri and good afternoon. Before I review our key operational updates for the quarter, I want to share my excitement around our lead asset, BA3011 with updates on part 1 of the Phase 2 non-small cell lung cancer study and the proposed path forward in soft tissue sarcoma, specifically UPS.
First, in non-small cell lung, we are thrilled with continued responses we’re observing as we enroll additional patients. As of data cutoff, we have enrolled 24 patients, 14 of which are efficacy evaluable. We continue to see responses in both monotherapy and combination therapy with nivolumab in non-squamous non-small cell lung with 4 out of 8 partial responses to monotherapy and 1 with complete response out of 4 patients in the combination arm. These responses are quite remarkable, especially in this multi-refractory patient population. We anticipate a full interim data set of approximately 20 patients through multiple scans by the end of this year. We will wait for the full interim data analysis before making detailed future study determinations, but we are thrilled to see compelling anti-tumor activity thus far with 3011 in both monotherapy and in combination with nivo.
Moving on to UPS, as Philippe noted, we are very pleased to be moving into part two of the study, the potentially registrational portion of the trial. We are currently finalizing the protocol and anticipate that study enrollment in dosing will commence by year-end. In addition to UPS, we continue to see positive anti-tumor activity across several soft tissue and bone sarcoma subtypes. We have already exceeded our internal do criteria for osteosarcoma, liposarcoma and synovial sarcoma and continue to enroll other sarcoma subtypes. In terms of our overall sarcoma strategy, we are initially focused on UPS with an opportunity to expand our label to include other sarcoma subtypes should we obtain approval in UPS. UPS represents a significant commercial opportunity as a stand-alone indication. However, given the encouraging anti-tumor activity we’re observing in other subtypes, coupled with a significant unmet medical need, we see real value in potentially expanding our sarcoma footprint over time.
Now turning to our second lead CAB-ADC product candidate, BA3021, a CAB-ROR2-ADC. As a reminder, there are no other therapies targeting worth in the clinic, so we have the potential to have a first-in-class treatment for solid tumors. In Phase 1, we saw impressive responses in ROR2-positive patients refractory to PD-1 therapy, including 2 PRs in non-small cell lung, 1 PR in head and neck cancer and a complete response in a melanoma patient who remains a complete remission off treatment for over 2 years. To date, we have three Phase 2 trials on going with 3021 and I’m happy to provide an update as to where we are with each, beginning with non-small cell lung. The non-small cell lung trial in refractory patients is enrolling this plant and currently dosing with an interim update of the preliminary cohort of up to 20 patients following at least 3 months of therapy anticipated at the beginning of next year.
Turning to the melanoma trial, which is being conducted in patients refractory to PD-1 therapy, non-evasive liquid biopsy assay has been validated and we anticipate initiating screening with this assay by the end of the year. We remain very excited about the potential of 3021 and melanoma patients, particularly with the potential acceleration of enrollment following full implementation of the liquid bioassay. The third Phase 2 study we’ve initiated with 3021 is in refractory patients with head and neck cancer. This study continues to enroll and is actively screening patients. We anticipate multiple patients dosed on year-end. To round out our CAB-ADC programs, we are supporting a multicenter investigated initiated Phase 2 clinical trial of 3011 or 3021 in patients with platinum-resistant ovarian cancer. To date, a total of 10 patients have been dosed five in each program. This trial is ongoing, and we will provide an update as one becomes available to us.
Now I’d like to talk briefly about updates for our CAB-CTLA-4 antibody, BA3071. This Phase 1/2 trial is being conducted in tumors known to be responsive to CTLA-4 treatment and will evaluate safety and tolerability of 3071 in monotherapy and in combination with nivolumab. This trial is progressing as planned with the first 2 cohorts completed without any DLTs or SAEs reported. The third cohort, which is at a dose equivalent to the approved dose of ipilimumab is ongoing with the DLT observation period anticipated to conclude by year-end.
Turning to our preclinical pipeline. BioAtla has several candidates in IND-enabling phase that include CAB bispecifics with second-generation ADC antibodies. Regarding our CAB-EpCAM CAB-CD3 bispecific BA3182, we received written pre-IND feedback from the FDA that our preclinical package is adequate to move forward, and we will remain on track with IND submission by the end of this year. We also remain on track for potential near-term IND submissions for preclinical next-generation CAB candidates in 2023 and beyond.
With that, I’d like to hand it over to Rick to review the third quarter 2022 financials.
Richard Waldron
Thank you, Scott. As of September 30, 2022, we had $178.1 million in cash and cash equivalents compared to $245 million as of December 31, 2021. We expect current cash and cash equivalents will be sufficient to fund planned operations, including all ongoing CAB product development programs into second half 2024. As a reminder, we control all CAB product market rights in the U.S., 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 to stockholders.
For the third quarter ended September 30, 2022, we reported a net loss of $25.8 million compared to a net loss of $22.9 million in the same quarter of 2021. Research and development expenses were $19.8 million for the quarter ended September 30, 2022, compared to $16.6 million for the same quarter in 2021. The increase of $3.2 million was primarily driven by our 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 $6.3 million for the quarter ended September 30, 2022, compared to $7.1 million for the same quarter in 2021. The $800,000 change was attributable to a decrease in stock-based compensation for the 2022 period. We expect our G&A expenses to moderately increase to support development of our product candidates, advance our intellectual property portfolio, support pre-commercialization activities for our product candidate BA3011 and satisfy requirements as a public company.
Net cash used in operating activities for the 9 months ended September 30, 2022, was $66.1 million compared to net cash used in operating activities of $41.3 million for the same period in 2021. The increase in net cash used in operating activities for the first 9 months of 2022 is primarily due to an increase in research and development expense related to our program development efforts as compared to the first 9 months of 2021.
And now back to Scott.
Scott Smith
Thank you, Rick. We are very pleased with the progress that we have made this quarter across the portfolio. We are excited with the compelling clinical profile that is beginning to emerge in treatment refractory non-small cell lung cancer and are eager to advance into the potentially registrational part of the Phase 2 study in UPS. We also remain encouraged for continued execution around our other promising CAB assets in multiple cancer indications. We are well poised to reach several value-creating milestones include inflection points with our innovative CAB assets and remain enthusiastic about the future. BioAtla will continue to have strong focus on execution with the goal of pursuing indications of high unmet medical need that we feel will have significant impact for patients and our shareholders worldwide.
With that, we will now turn back to the operator and take your questions. Thank you.
Question-and-Answer Session
Operator
[Operator Instructions] Our first question comes from Brian Cheng from JPMorgan. Brian, please go ahead.
Brian Cheng
Thanks, and congrats on the progress. And thanks for taking my question. Can you provide some color on the time to respond and the durability of response that you’ve seen across the 14 patients that you presented today for AXL-positive NSCLC? And then I have one follow-up on UPS.
Scott Smith
Thank you, Brian. Thanks for the question. I will ask Philippe to give some color around your – the two parts of your first question around the time to respond and also initial thoughts on durability, although I will say it is awfully early for us in the study to be able to be to have any definitive view on duration of durability at this point, but Philippe?
Philippe Martin
Yes. Thanks, Scott. So we saw a response as early as first cycle generally response either observed at first cycle or a second cycle – first scan, I’m sorry, your second scan, that’s what I like, first scan or second scan, scan is at 6 weeks. And with regard to durability of response, we’ve – as Scott said, it’s early for us to give you a number, but the patients have been responding have been on treatment as long as 9 cycles, so about 9 months on treatment. So, so far, we are not seeing a problem with durability.
Brian Cheng
Great. And then on the UPS front, we noticed that there is a more intensive dosing arm that you’ve planned for part two Phase 2 for the UPS side. I thought that the response that you had previously was already pretty competitive in the space. So I’m wondering if you can shed some light on why there is an additional more intensive dosing arm. What is the importance of this dosing arm? And is this more of an exploratory exercise to see if you can get a better response. Thank you.
Scott Smith
Yes. Thank you very much for the question, Brian. We have seen – if we combine our Phase 1 and Phase 2 UPS patients, we’re seeing a 50% response rate, which is very, very high in this particular population. UPS like other sarcomas very difficult disease, very difficult to get patients under control. And so this high-intensity dose arm is just exploratory to see if we can get even better efficacy. We will also have an arm at the current 1.8 million ounce per kilogram dose that we will move forward. And after we have an initial dose of patients, we will choose one of those two arms to move forward. So overall, I think it’s a very positive signal that the safety and tolerability that we have seen so far allows us to try a more intensive arm. If we don’t see good benefit risk coming into that, we will go to the current arm. So I think overall, a very positive development.
Brian Cheng
Great. Thanks, Scott.
Operator
Our next question comes from Kelly Shi from Jefferies. Kelly, please go ahead.
Kelly Shi
Congrats on the great progress. And thank you for taking my question. Firstly, so for the 24 patients enrolled into the non-small cell lung cancer cohort, for 3011? And how many of the 10 patients, not efficacy evaluable actually non-small I mean non-squamous? And why should we expect the next data update? And also, do you extend – do you intend to enroll more patients beyond these 24 patients? And I also have a follow-up.
Scott Smith
Thank you very much for the question, Kelly. Yes, we have actually now the 24 patients was a data cutoff in late October, we’ve now enrolled 27 patients. We expect to make our decisions on how to structure part two of the study and make our decisions on how to approach the agency, the FDA on part 2 based on a bolus/reports of 20 patients evaluable through multiple scans. So – but we do, under the protocol, have an opportunity to enroll up to 40 patients. And there are some questions still outstanding that we’d like to answer around squamous versus non-squamous monotherapy versus combination therapy, etcetera. So we will continue to enroll some more patients but the initial cohort that we are going to use to make decisions off from is 20 patients just so of the additional patients who have not yet gone through multiple scans that are in the study, I believe they are all known squamous. I don’t know personally the L27, but 24 of the cutoff, I believe they are all non-squamous patients. So any correction there?
Philippe Martin
No, that is correct. And to answer your first question, 12 out of the 14 efficacy variable patients were non-squamous patients. We still have two squamous patients. These are the same patients we had talked about during the last update. We’ve not enrolled new squamous patients.
Kelly Shi
Great, thanks. And also for the UPS, can you actually talk or share more details regarding the FDA feedback and also more color on the registrational trial design?
Scott Smith
Yes. UPS, Kelly, Philippe, do you want to talk a little bit about – a little bit more context on the written response from the FDA and the design moving forward.
Philippe Martin
Yes. So we set a proposal to FDA for the registration part of the study. FDA, we asked for ORR as a primary endpoint. We also last for a sample size of 80 patients and also ask for including the more intensive dosing arm, which FDA had no objection to – we – the study design is the 1.8 milligram dose in 1 arm and then the more intensive building in another arm. We’re randomizing patients 20 in each of these two arms. And then we will make a decision on which of these two dose we go forward with and then add an additional 40 patients after that, so that the registrational dose will have 60 patients total.
Kelly Shi
That’s helpful. Congrats again.
Scott Smith
Thanks, Kerry.
Operator
Our next question is coming from Tony Butler from ROTH Capital. Tony, please go ahead.
Tony Butler
Thanks very much. I continue to be impressed with the non-small cell lung cancer data, especially in those previous PD-1, and part 2, where I believe last quarter, you made comments that you’d like to enroll 100 patients. Are you suggesting today or are you saying today that, that, in fact, could be registrationable and it’s true. Could the trial actually – would it be a trial without a control group? And would it – do you think that it would include monotherapy and combo at least within those 100 patients? In other words, 50-50, that’s question one. And number two, am I correct, or do I remember correctly, maybe that’s a better way to put it, a 20% response rate and NSCLC is commercially relevant for 3011? Thank you.
Scott Smith
Yes. Thank you very much for the question. So, the design of part two here is obviously contingent subject to discussion with the FDA. I believe there is a path and some precedents in this multi-refractory PD-1 failure, lung population to be able to do a single-arm ORR study. I am not able to determine at this point in time whether we move just the monotherapy arm for the mono and combo arms forward. We want to reserve the right to collect a little bit more data to be able to assess that more properly. But we are thrilled with the response rates that we are seeing. It’s I think a great sign that we are seeing significant efficacy in monotherapy. As we have gone from the Q2 into the Q3 disclosure, we maintained 50% response rate in the non-squamous monotherapy arm, 57% if you just look at PD-1 failure population there. So, very, very strong data. Based on our internal discussions and thoughts before the study started, we believe, again, this multi-refractory PD-1 failure population that a 20% ORR rate could be registrational, of course, pending agency review and benefit risk and some of those things. We thought that 25% and above would be commercially viable. It’s important to note that the AXL-positive – the group of AXL-positive non-small cell lung patients is quite large, trending in between 35% and 40% of the refractory population. And so being able to get to those response rates above 25% in this large population, I think will be highly commercially viable for us.
Tony Butler
I appreciate that. I may ask one follow-up. Obviously, you don’t have a waterfall plot, but you would have a view about this from subsequent scans at least over time. Have responses or do you have patients where responses deepen over time? Thanks.
Scott Smith
I think generally, the pattern in past patients has for their responses to deepen over time. I think we have talked about, for example, the complete response patient that was a partial response on first scan and a complete response on second scan. Most of the patients that we have seen in Phase 1 and Phase 2 do continue to deepen the response over time. Philippe, do you want to put any more color on that?
Philippe Martin
No, I think you have answered the question, Scott. We generally see patients depending their response over time. I think that’s what we have seen in Phase 1 and certainly what we are starting to see here in Phase 2.
Tony Butler
Scott and Philippe, thank you.
Scott Smith
Thanks Tony.
Operator
We have a question from Arthur He from H.C. Wainwright. Arthur, please go ahead.
Arthur He
Hi. Good afternoon everyone. Congrats on the strong data to confirm the activity for the 3011. Just regarding the non-small cell lung cancer trial, I just wonder what the net rent of the 10 patients, how many patients received the monotherapy compared to the competition there?
Scott Smith
Thank you for the question Arthur. I believe as we go from 14 to the 24, I believe that the distribution of mono and combo is relatively even between mono and combo two groups, yes. So, we will start to catch up and see some more combination patients come in. I think it’s maybe a little higher factor being early here. But we should see some more combinations – combination patients come in, which we are excited about because not only do we see a complete response there, but we would also like to have more data to fully evaluate the risks and benefits of the combination arm. Thanks for the question.
Arthur He
Got it. That makes sense. And for the BA3021 program, regarding the non-small cell lung cancer enrollment, could you give us an update regarding the status and currently, how many active sites in the U.S.?
Scott Smith
So, I will let Philippe in a minute to answer the active sites in the U.S. I don’t have the number exactly with me. But I will say that the more to lung program is probably three months to four months behind where we are with the AXL program, which started later and the AXL is ahead of it, and then continues to be that way. We are seeing reasonable enrollment. I would expect to have a good group of patients for us to take a look at by the time we get to year-end. This year, we want to get through multiple scans. So – and I think right now, the timing that we are looking at to talk about that data set is likely in Q1 2023, whether during the actual quarter or the Q1 call. But I think that’s Q1 2023 event when we have enough patients through multiple scans to be able to really understand that data. And like I say, going well, I think the execution of that study probably three months to four months behind where we were with that. So, Philippe, any thoughts on the exact number of sites.
Philippe Martin
Yes. We have approximately 35 sites initiated. Some of these sites are in Hong Kong and Taiwan, but the vast majority, about 30 of them are in the U.S. We are also in the process of initiating sites in Europe as we see the approval to do that across a number of countries. So, currently 35, but it will continue to grow.
Arthur He
Thanks. If I could, I just raise one last question. For the BA3011, have you guys see any correlation between the AXL expression with the clinical activity for the drive?
Scott Smith
Yes. So, I think if we are talking about the sarcoma program for 3011 of the AXL-ADC, we definitely see a relationship. And we saw the relationship relatively early in Phase 1. These sarcoma patients have heavy tumor burdens. And it seems like you need high levels of AXL expression, i.e., over 50% to really move the needle. Now, in sarcoma, it’s very bimodal. Patients either express it at a very small degree or none at all or at a very large degree, there is not a lot of middle ground there. But we see relationship between actual expression and response for sarcoma. For long, it looks a little bit different. It’s probably too early for me to make a definitive statement on the relationship between expression and response. We are seeing responders at lower levels of AXL expression in non-small cell lung and at high levels. So, I would like to gather some more data, I would like to get this next six, seven patients through multiple scans, take a look at that full 20 patient subset and make some determinations relative to actual special and response, but it doesn’t look different than we saw with sarcoma.
Arthur He
Got it. Thanks Scott and again congrats on the progress and talk to you soon.
Scott Smith
Thank you very much.
Operator
[Operator Instructions] Our next question comes from Reni Benjamin from JMP Securities. Reni, please go ahead.
Reni Benjamin
Thanks. Good afternoon guys and thanks for taking the question. Congrats on the progress. I would like to maybe just start off with the non-evaluable patients that you have so far. Can you just tell me how many are on drug, as of now, it seems like several maybe just don’t have scans yet. Can you give us the breakdown of that? And can you also just remind us that if all the responses to-date have been confirmed. And I guess finally, are there any learnings that you have been able to ascertain from the non-responders that might help you to further define an exclusion criteria?
Scott Smith
So, to answer your last question first, I don’t know that we have really defined learnings yet from the non-responders. I know from a couple of non-responders, they were more heavily pretreated and failed more prior lines of therapy than others. So, that seems to be a trend which continues. In terms of a confirmation, so of the five patients have responded, the four partial responses and one complete response, three of those are confirmed, two have come in more recently, and they have not had second scan yet. So, once those second scans come in, and if they remain, we will confirm those. The trend has been for patients that do respond early continue to improve response. So, our hope is that those two will be confirmed, but they just haven’t been confirmed yet because they haven’t had second scan. And then the first question you asked, I am sorry, I need time to write that down.
Reni Benjamin
That’s okay. Sorry, I probably shouldn’t invest all three at once.
Scott Smith
No. Just forget.
Reni Benjamin
Just the non-evaluable patients, are they still on drug? I couldn’t do the math just, there were 24 year-old, there 14 efficacy. I think 10 are not evaluable, but there might be a further breakdown.
Scott Smith
Yes. I believe the majority of those affiliate again, can break down the exact number source. The majority of those – the large majority are patients that are dosed just have not had scans or not have had two scans yet into the on drug, there is a couple of that are on drug, I believe. But Philippe, do you want address those?
Philippe Martin
Yes. So, 24-patient annual 14 efficacy evaluable, the 10 difference is that we had six patients that are currently ongoing, being treated, but haven’t reached their first scan. We had two patients at the time of data cutoff that were not dosed yet. And we had the two patients that we drew consent early, which are the same patients we mentioned at the last quarterly call. So, that’s the breakdown for the 10 patients.
Reni Benjamin
Terrific. Thanks Philippe. And just one final one for us. As I evaluate the combo data and the response rates, can you help maybe define what would be – at what point do you kind of cut they or can you evaluate any different checkpoint or a different combination?
Scott Smith
Yes. I think it’s hard for me to answer that question with exact numbers. I think what you want to see in general is you want to see something emerging from that, that is better than what you are seeing from the drug in monotherapy. You want to see a better benefit risk emerging or there is no sense going in combo unless there is a subset of patients who would are more likely to benefit from combination than they are for monotherapy. I think what we are seeing in combination therapy is maybe more of an [indiscernible] numbers, and that’s why we are really excited to get some more combination patients in to see what’s going on there because we would like to see efficacy at or above what you are seeing in monotherapy and not significant additive toxicity. I think that’s overall what we are looking for. So, we have not given up on the combo arm by any means. Of the four patients there, we do have a complete response. We have two patients who were on the study because of toxicity that I believe was before it was related to nivolumab. So, small numbers, let’s get another 4, 5, 6, up to 10 patients in that arm when we can take a look and see what’s there. But what is really sort of heartening to us is that you see four patients in monotherapy responding. Those patients all five patients have responded here are still in response and remain in the study, which is very, very encouraging as well. And the drug certainly seems to be active in monotherapy. And we got a little more work to do a few more patients in the combination side to make final determination there.
Reni Benjamin
Prefect. Thanks very much for taking the questions and congrats.
Scott Smith
Thank you.
Operator
And this concludes our question-and-answer session. I would like now to turn the conference back over to Scott Smith, President of BioAtla for any closing remarks.
Scott Smith
Yes. Just thank you all very much for your time and attention. We are really proud of the progress that we have made, not only from Q2 to Q3, but this whole year. The year started off as a tough year for critical development from Omicron, COVID-19 perspective. But we thought through that, we remediated the pace of clinical development is going very well. The results are going very well. More than anything, I think when we take a look at the safety and efficacy data, the benefit risk that’s emerging here, at least for 3011 that we can – that we have got enough patients to make this assessment. You really seem to see the CAB technology playing out in the clinic. You see a side effect profile, which is very much in line with the idea of using technology to greatly eliminate to sort of really produce or eliminate on-target off-tumor toxicity and eliminate some of that baggage that you get with cancer antigens, which are very promising, but also exist on healthy tissue as well. So, we are seeing the CAB technology and move forward in the clinic.
The execution has been well. We are really excited about moving 3011 into what could be a potential registrational study in UPS moving forward into part two of the lung study, and we are really excited about next year as well were two data coming, CTLA-4, data coming from the Phase 1/2 study there. And also, we should be bringing a CAB-EpCAM CAB-CD3 bispecific antimitotic by the end of this year and start of dosing that next year. So, we should have four candidates in the clinic next year and approximately 10 cancer indications. And we are really excited, not just about 3011, which we are very excited about, but the whole portfolio going forward.
So, thank you all very much for your time and attention.
Operator
The conference has now concluded. Thank you for attending today’s presentation. You may now disconnect.
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