Atara Biotherapeutics, inc (ATRA) Q2 2021 Earnings Call Transcript

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Atara Biotherapeutics, inc (ATRA -0.54%)
Q2 2021 Earnings Call
Aug 9, 2021, 4:30 p.m. ET

Contents:

• Prepared Remarks
• Questions and Answers
• Call Participants

Prepared Remarks:

Operator

Good afternoon everyone, thank you for standing by, and welcome to the Atara Biotherapeutics' Second Quarter 2021 Financial Results Conference Call. [Operator Instructions] I now would like to hand the call over to Eric Hyllengren, Vice President of Investor Relations and Finance at Atara Biotherapeutics. Please go ahead, sir.

Eric Hyllengren -- Vice President, Investor Relations and Finance

Thank you, operator. Good afternoon everyone, and welcome to Atara's second quarter 2021 results conference call. Earlier today, we issued a press release announcing our second quarter financial results and operational progress. This press release and an updated investor presentation are available in the Investors and Media section at atarabio.com. On today's call members from the Atara executive team will provide an update on our financial results and operational progress, and also review our upcoming key milestones and objectives.

Joining me on today's call are, Dr. Pascal Touchon, President and Chief Executive Officer; Dr. Jakob Dupont, Executive Vice President and Global Head of Research and Development; Utpal Koppikar, Chief Financial Officer; Joe Newell, Chief Operations Officer; Dr. Jose Vidal, Head of GMP Quality and Process Sciences; Dr. AJ Joshi, Chief Medical Officer; and Dr. Kristin Yarema, Chief Commercial Officer. We will begin with prepared comments from Pascal and Jakob, then open up the call for your questions.

We would like to remind listeners that during the call, the company's management will be making forward-looking statements. Actual results could differ materially from those stated or implied by our forward-looking statements due to risks and uncertainties associated with the company's business. These forward-looking statements are qualified in their entirety by the cautionary statements contained in today's press release and the company's SEC filings. These statements are made as of today's date and the company undertakes no obligation to update these statements.

Now, I'd like to turn the call over to Pascal. Pascal?

Pascal Touchon -- President and Chief Executive Officer

Thank you, Eric, and thank you all for joining us this afternoon. We have completed a strong first half of 2021 and are making good progress on all three of our strategic priorities tab-cel, ATA188 in multiple sclerosis, and our next-generation allogeneic CAR T programs. Reported by a breakthrough therapy designation, we have been having regular dialog since January with the FDA. We recently conducted positive meetings with the regulatory team at the FDA, and gained alignment, clarity, and actionable next steps in order to submit the tab-cel BLA.

First, we gained alignment with the FDA on the key methodologies for evaluating comparability between tab-cel clinical and commercial products. In addition, the FDA asked for and we will provide to them data on substantially all tab-cel lots made to date by Atara. We believe this should clear the way for the FDA to make a determination at an upcoming Type B CMC meeting regarding our expanded data package supporting comparability between the product use in a pivotal clinical study and the intended commercial product.

Next, the FDA decided it cannot make a determination of comparability between the non-pivotal products and the pivotal clinical study product, and clinical data from the historical non-pivotal study will not be pooled with the pivotal ALLELE study data. Rather we intend to present these data in parallel as part of the BLA submission. Importantly, at this time, the FDA has made no new request of Atara to conduct additional clinical studies, develop new assays or conduct new manufacturing offloads. We are confident that we will have a robust data package to demonstrate comparability to the FDA between pivotal and commercial product versions of tab-cel, and we are encouraged by the ongoing interactions as we work toward finalizing of CMC Module 3 for the BLA submission.

Turning to the pivotal ALLELE study. We have recently successfully completed the analysis of the Q2 that occurred previously requested by the FDA. Topline data shows strong objective response rate in line with prior results and a consistent safety profile with no new safety signals. In addition, we now have new robust durability data as well. These data from a pivotal study are impressive for such an [Indecipherable] and [Indecipherable] conditions like relapsed/refractory PTLD, where patients have no treatment options. The latest data will be discussed with the FDA with Type B committee, and is what we plan to use as the basis of both the BLA and MAA submission.

As a reminder, we continue to plan to present the Phase 3, ALLELE data at an appropriate congress in Q4 2021. Looking ahead, we now have clarity around the required next steps, resolution and submission of the BLA for tab-cel. Although these have taken some time as Atara is a trailblazer for allogeneic cell therapy as a world and is paving the way of the first ever allogeneic off the shelf T-cell therapy to which figures the way findings, we now expect to complete the BLA submission for tab-cel in Q1 2022.

Our investment in U.S. commercial readiness activities have been shifted to recent timing, gating or spending versus what was previously anticipated, as we now plan for tab-cel approval and U.S. launch in the second half of 2022. As we continue to prepare for commercial launch, I'm very pleased to announce that cell therapy and oncology commercialization veteran Ameet Mallik, was appointed to the Board of Directors. Ameet, brings to Atara's Board a wealth of experience with U.S. payers, access and reimbursement strategies and launches of innovative oncology therapy including CAR Ts.

Now turning to Europe, where we are also making excellent progress. We recently had successful pre-submission, as well as Rapporteur/Co-Rapporteur meeting with EMA, and cleared all compliance checks. So we can now move forward to submit the EU market authorization application for patients with EBV positive PTLD in November of 2021. In parallel, there is a strong level of interest from ex-U.S. partners and our partnering discussions are progressing very well in line with our expectation to secure a partner for Europe by Q4 2021. Meanwhile, we are also actively and enrolling patients in our tab-cel Phase 2 multicohort study in other EBV-driven cancers. The sick study populations of which the largest two are EBV positive AID-LPD and EBV positive PID-LPD, may support meaningful label extension beyond second line PTLD.

Turning now to ATA188 our transformative product candidate for patients with multiple sclerosis. I'm very excited to announce that important new data will be presented in October ECTRIMS. These would include new magnetization transfer ratio imaging data and imaging biomarkers linked with myelination, in addition to the 2-year clinical data update from the Phase 1A open-label extension study. We are excited to present this new data and Jakob will have more to say in a moment.

Meanwhile, we continue to make progress enrolling the Phase 2 randomized, double-blind, placebo-controlled study or EMBOLD study. We are on track to conduct an interim analysis of the study in the first half of 2022, including efficacy and safety in patients with progressive forms of MS. Following this interim analysis, we expect to have further discussion with the FDA regarding potential study adjustment for pivotal intent. These are important discussions from both a regulatory and strategic perspective for the program and could provide optionality on how we advance development.

Momentum meanwhile continues to build in the community reinforcing the association between EBV and MS and the transformative potential of ATA188 patients. This was confirmed by a recent survey among top U.S. neurologists. We also continue to see significant interest from a number of large companies regarding a potential collaboration involving ATA188, as we truly have a unique asset, the only investigational therapy in a randomized controlled trial in progressive MS with disability improvement as the primary and booked.

Moving to our CAR T portfolio and first of mesothelin franchise program, ATA2271 and ATA3271, this mesothelin-targeted CAR T products are benefiting from a global strategic collaboration with Bayer, which is off to a strong start. For ATA2271 or autologous mesothelin CAR T program, we expect to present the first update on Phase 1 data for patients with advanced mesothelioma in Q4 2021. The off the shelf allogeneic version of this mesothelin CAR T program ATA3271 using a PD-1 dominant negative receptor and one 1XX CAR co-stimulatory signaling domain built on our EBV T-cell platform is currently in IND enabling studies and it's progressing well. We expect Bayer to submit an IND in the second half of 2022 and subsequently lead clinical development and commercialization activities. Turning to ATA3219 or allogeneic CD19 targeted CAR T for patients with B-cell malignancies. We plan to submit an IND in Q1 2022, in line with our strategic goal to develop this asset as best-in-class for B-cell malignancies.

Moving to our financials. With regard to our cash positions and runway, our cash burn in Q2 was $61.8 million and we ended the second quarter of 2021 within $373.4 million in cash. With this cash balance and our updated and well controlled plan expand profile, we believe we are sufficiently funded into 2023. As we turn ahead into the third quarter of 2021, I am delighted to see how far Atara has come from this time a year ago. Each and every one of our staff has delivered on our goal of saving and improving lives of patients with serious disease. On a daily basis, we partner closely with clinical study site with our manufacturing and logistic partners and our collaborators in order to ensure patients who could continue to access our therapy. With the hard work of the Atara team, we are on a clear path to file our tab-cel regulatory submissions and bring this life-saving medicine to patients in need.

I will now turn the call over to Jakob. Jakob?

Jakob Dupont -- Global Head, Research and Development

Thank you, Pascal. I am pleased to provide further details on the progress we made during the second quarter in advancing our three strategic priorities. Starting with tab-cel. We have aligned with the FDA on several key aspects required for BLA submission. Regarding comparability of tab-cel clinical and commercial product, we reached alignment on methodologies for evaluating these two sets of products. As requested by FDA, we are providing data on nearly all pivotal and commercial tab-cel lots manufactured to date. We believe FDA should agree on our comparability data package when we discuss these new data at an upcoming Type B CMC meeting. This belief is directly related to the consistent and tightened process performance data that was generated from the pivotal and commercial production campaigns, as well as the fact the process changes between pivotal and commercial were minimal and mainly related to the commercial GMP compliance of the EBV viral reagent used in manufacturing.

With regard to comparability of historical non-pivotal tab-cel product versus pivotal clinical study product, the agency recently clarified that they would like to see comprehensive analytical data on most historical lots. Therefore, we have agreed with the FDA that comparability cannot be established because we do not have product available for some of the lots manufactured by MSK in the past. This important resolution of comparability means a clinical data generated using historical non-pivotal product will not be pooled with pivotal clinical data. Importantly, this decision is consistent with the prior FDA decision to evaluate in parallel, the data of a CAR T product from an academic centers non-pivotal product versus the industry partners' pivotal clinical study product, for which ultimately, the FDA granted marketing approval.

Turning to the pivotal ALLELE study, we have recently successfully completed the analysis of the Q2 data cut present requested by the FDA for the Phase 3 ALLELE pivotal study. Top-line data evaluated through independent oncologic and radiographic assessment shows strong ORR in line with prior results with half the patients responding, and the safety profile consistent with previously published data with no new safety signals. Importantly, this new data cut demonstrates new robust durability of response. This latest data cut is what we plan to use as the basis for both the BLA and the MAA submissions, while also providing additional supportive data from our historical non-pivotal studies, expanded access and compassionate use study patients.

To summarize next steps, we anticipate speaking with the FDA in a Type B CMC meeting to discuss our expanded data package on comparability between pivotal, clinical study product and commercial product as well as a Type B clinical meeting to discuss the latest data cut from the ALLELE study, now with robust durability of response data requested by the agency that will form the basis of the BLA filing. Requests to FDA for these meetings have already been made and pending alignment, we could then file the BLA in the first quarter of 2022.

As Pascal mentioned, we've also made excellent progress in Europe. Tab-cel's prime and orphan drug designation with EMA has enabled regular engagements with the agency and our PIP compliance checks have been successfully cleared. Our recent successful pre-submission as well as Co-Rapporteur/Rapporteur meetings means that we have cleared the path for the MAA submission in the EU. Therefore, we can submit the market authorization application for patients with EBV positive PTLD in November of 2021. Taking a step back and thinking about PTLD patients in dire need of treatment options, we recently joined the Rare Disease Company Coalition alongside other rare disease leaders and constituents to engage in conversation with policymakers on the need for speed and access for life changing therapies. Atara is committed to leading the path forward for transformational therapies for rare disease patients.

Moving now to ATA188, our product candidate for progressive multiple sclerosis. We are excited and look forward to presenting at ECTRIMS in October, long term, 2-year clinical data from the Phase 1 open-label extension, and new translational data from the Phase 1 study of ATA188 in progressive MS. Included will new imaging biomarker data considered to reflect the state of myelinate -- myelination in the CNS known as magnetization transfer ratio or MTR. With respect to MTR, decreased MTR in MS lesions may correlate with demyelination and axonal loss in MS patients, while increased MTR may correlate with remyelination. These data may provide key information on the mechanism of EDSS improvement in our ATA188 clinical data. We're excited to present these new data in October. We also plan to use MTR as a relevant imaging biomarker correlated with disability improvement in our ongoing Phase 2 EMBOLD study.

Turning now to our CAR T programs. In addition to Pascal's comments, I would also add that we are making excellent progress on our mesothelin franchise programs with our partner Bayer. This partnership is helping to demonstrate the progress of the technical and manufacturing elements of our EBV T-cell platform. We are delighted to leverage the capabilities of such an experienced company as Bayer and look forward to providing further updates later this year. ATA3219, our allogeneic CAR-T for patients with B-cell malignancies is also advancing well and we believe that this therapy could be a best-in-class treatment in B-cell malignancies, as there is still significant unmet need despite increased therapeutic options.

Finally, I'd like to extend a warm welcome to our newest leadership team member, Chief Scientific Officer, Dr Cokey Nguyen. Cokey comes to us most frequently or most recently from Fate and brings his deep experience in CAR T paired together with a strong conviction around the unique benefits of our EBV platform to drive our exciting CAR T-cell franchise forward into the future.

I'll now turn the call back to the operator to begin the Q&A portion of the call. Operator?

Questions and Answers:

Operator

[Operator Instructions] Our first question comes from the line of John Newman with Canaccord Genuity. You may proceed with your question.

John Newman -- Canaccord Genuity -- Analyst

Hi there, thanks for taking my question, and congrats on the good progress here. Jakob, you mentioned that submission has been made -- a request for a Type B meeting with a comparability data for tab-cel. Just curious if you know about but when that might take place. And then on the clinical side, beyond the most recent data look for ALLELE that you've conducted, just curious if you think the agency will require any additional data looks in the future, maybe added with some additional patients for longer follow up. Thanks.

Pascal Touchon -- President and Chief Executive Officer

Thank you, John for your question. Jakob, do you want to take the first one?

Jakob Dupont -- Global Head, Research and Development

Yeah. Thanks, Pascal. And thank you, John. So yes, we have submitted meeting request for the Type B meetings both for CMC comparability and for the clinical discussion as well. Now per PDUFA timelines, we should hear back from the agency within 60 days of that request. So we believe that this meeting will occur within the next 2 months.

Pascal Touchon -- President and Chief Executive Officer

And the second question on clinical data beyond ALLELE?

Jakob Dupont -- Global Head, Research and Development

Yes, absolutely. So we believe that this new analysis for ALLELE is strong enough to support a BLA filing. But of course, if the FDA wants updates specifically such as safety with a subsequent 90 days safety cut, we can certainly do that. But we do believe that the current Q2 data cut for ALLELE is sufficient to support the BLA submission, as well as the MAA application. And as you know, we're also going to be providing historical non-pivotal data and EAP and FPU clinical data in the BLA and MAA filings in parallel, but not in a pooled fashion due to the outcome, which we thought was quite favorable in terms of non-comparability between historical and pivotal material.

Pascal Touchon -- President and Chief Executive Officer

Does it answer your question, John?

John Newman -- Canaccord Genuity -- Analyst

Yes, it does. Thank you.

Operator

Our next question comes from the line of Jonathan Miller with Evercore ISI. You may proceed with your question.

Jonathan Miller -- Evercore ISI -- Analyst

Hey guys, thanks for taking my question and congrats on the progress. It does seem like the FDA is being pretty cautious on the tab-cel BLA. I guess given that you can't pool and that you think the Q2 update on ALLELE is as far as you're going to need to go, what is the duration of response that you'll be able to claim on the pivotal data relative to what you could have claimed on the pooled data? Separately, it seems like IND timelines for the allogeneic CAR-T programs are going to be a little bit back -- toward the back end of the prior guidance. I just wondered, what's the gating factor on those INDs going forward from here?

Pascal Touchon -- President and Chief Executive Officer

Thank you for your question. Do you want to take the first question, Jakob, please?

Jakob Dupont -- Global Head, Research and Development

Yes, absolutely. So I would say that we've made great progress with the FDA in terms of understanding the comparability issues, and then obviously also providing this Q2 data cut that the FDA requested from us in October of last year, specifically to provide durability data on the patients that had already enrolled. Now, the guidance that the FDA has provided to us, which they provide to other sponsors is that they want to see durability of that response, which basically means that from the time that a response is detected, you want an additional six months of follow up on those patients, since the time of response. So if you think about -- we got that guidance in October of last year. We let the data mature further, collected the data based on Q2 data cut and provided it to our independent review facility for independent oncologic and radiographic response. It really fits those criteria of six months duration of response after that initial response is detected, and that's pretty standard request from the agency.

Pascal Touchon -- President and Chief Executive Officer

Yeah, and I think the fact that we align with the agency on the durability of responses you see and we have the data now makes us very confident in this [Indecipherable] data package that we'll present in the forthcoming Type B clinical meeting. Now, on your second questions, it's just that we have refined our thinking on the different manufacturing timelines for this program and developments that is needed to file the IND. The work we are doing on this platform as we progress in the specific programs we, by the way, help the rest of the early pipeline, and we are leveraging our platform there. So there is no particular aspect there that is a particular challenge apart from the fact that we have now fine tuned the exact timing for the IND filing. And for ATA3219 will be of course Atara filing the IND wells. For 3271 will be Bayer filing the IND there.

Now we also trying in developing these IND package to make sure that we can optimize our chance of adding the two best-in-class platform for allogenic CAR T. And this is, we believe where ATA3219 in particular could have significant potential advantage in optimizing characteristic of the cells to make sure that we can leverage the innate properties of EBV T-cells together with 1XX as a co-stimulatory domain to really make something that could go to the clinic with the potential and the goal to be a best-in-class in B-cell malignancies. Does it answer your question, Jon?

Jonathan Miller -- Evercore ISI -- Analyst

Yes, absolutely. Thank you.

Operator

Our next question comes from the line of Salim Syed with Mizuho Securities. You may proceed with your question.

Salim Syed -- Mizuho -- Analyst

Great. Good afternoon, guys and congrats on the progress. A couple from me if I can on ATA188. So Pascal, you sound pretty excited. I know the press release even uses that word, exciting new imaging data. So as much as you can see here about the MTR and whether that's actually a -- refers to myelination patterns, are you seeing -- or you think you're seeing remyelination with the -- with ATA188? And curious to get your thoughts on the FDA being able to use this as a biomarker for accelerated approval just given everything we've seen with accelerated [Phonetic] approval around Alzheimer's. Thank you.

Pascal Touchon -- President and Chief Executive Officer

Thank you, Salim. We are definitely excited, but we are not going to give you the data. That you will have to wait for October. But AJ, do you want to comment on MTR and what we believe this particular set of data is very important, and what's our plan with the FDA in terms of how this could be used as a biomarker.

AJ Joshi -- Chief Medical Officer

Yeah, Thanks Pascal. Hey Salim. Yes, I think -- with the MTR data, you've heard that it's pretty much the -- and when you look at MRI biomarkers looking at myelination, that's really the most used one in all the studies that you're looking at. And as you might imagine, it's been correlated with decline in EDSS, so decline in disability. So if you have lower MTR, you actually have -- lower MTR means you have demyelination and that means you have decline in disability. So that correlation has been made. What's interesting is, no one's actually shown improvement because, as you know, no product has shown improvement in disability in a progressive situation. But what is interesting is, if you take a look at MTR in relapsing disease. So this is where you've got an active lesion and you use a therapy that works in inflammatory disease, you will actually see MTR increase because you get remyelination once the inflammation calms down.

So, you do see MTR increasing when you have remyelination. It's just never been shown in the progressive setting. So from that standpoint, what we're trying to do is, we're trying to -- look MTR's relatively established as a measure of myelination, both demyelination and re, and we're now trying to apply that to the study data that we have now. So obviously, we're looking forward to presenting the data coming in October.

And in terms of how you could leverage this going forward, it's really not been used as a -- anything like a surrogate mark or anything like that to date. But again, a lot of that we think is just because there hasn't been a lot of good reason to take a look at disability improvement and MTR changes. So certainly, we're going to very closely monitor MTR throughout the course of the phase -- of the EMBOLD study. And we're going to be talking to FDA and we will be including all of the MTR discussions in those conversations. But today, it's a little bit too early to say, yes, there is -- this is going to be an established biomarker. But from a scientific perspective and the clinical perspective, it is established within the scientific community right now.

Pascal Touchon -- President and Chief Executive Officer

Yeah. And as AJ has said it will be one of the endpoint we'll be following in the current randomized controlled trial. So not only we have data coming in October on the Phase 1 but we'll have also data coming forward later on the Phase 2 study when we get access to this data. So that's something of a plan in terms of leveraging these particular biomarker that has been used in a number of studies, but not yet correlated with improvement in disability and that could be something very exciting.

Salim Syed -- Mizuho -- Analyst

Super helpful. Thanks so much.

Operator

Our next question comes from the line of Phil Nadeau with Cowen. You may proceed with your question.

Phil Nadeau -- Cowen and Company -- Analyst

Good afternoon, and congrats on progress, and thanks for taking our question. A couple on the comparability issue, you mentioned briefly in the prepared remarks, what the differences are between the pivotal and commercial material. Could you go into a bit more detail at the significance of those differences? And then secondarily, the other two methodologies have been clearly defined. Can you talk a bit more about your confidence that the FDA will find the pivotal and commercial material comparable? Thanks.

Pascal Touchon -- President and Chief Executive Officer

Certainly. Jose, do you want to address the first question on the difference between pivotal and commercial material? And then Jakob you can address second question on the FDA, how we perceive a confidence that we have, that we have data that will be -- bring them to decide positively on comparability. Jose?

Jose Eduardo Vidal -- Head of Quality Assurance and Process Sciences

Certainly, Pascal. Yes. The difference is the actual source and grade of the Epstein-Barr virus that we use in the manufacturing process. We switch from a clinical research grade producer cell lines or produce the virus into our full GMP commercial grade producer cell line. And we switched also the manufacturing place of the virus to our own facility from the previous CMO as the CMO had no capacity to supply commercial volumes. We have done full characterization on that and we are pretty confident that it's a meaningful change. But that's the summary of the change between the pivotal and clinical material.

Pascal Touchon -- President and Chief Executive Officer

Thank you. And Jakob, how do we see the data package for the FDA?

Jakob Dupont -- Global Head, Research and Development

Absolutely. So I think one of the really important things so that we learned from the FDA is, their thinking evolved around tab-cel which is that, as you know, the first allogeneic T-cell product, which is going across for FDA approval. We've learned that they have this requirement now to see the data from all the lots that have been created in order for a determination of comparability to be made between pivotal material and commercial material. That was the reason why we could not deem comparability between historical and pivotal because we simply didn't have some of the lots from Memorial Sloan Kettering. But what we do have are virtually all of the lots from pivotal and commercial, so that we can do full comparability analysis. So having the agency give us the lay of the land and what the requirements were in terms of sharing the totality of that data, that is something that is really accomplishable from our perspective, and having that clarity from the agency is really valuable. So that's why we put the Type B meeting request in, which again, will occur within the next 60 days or so. And we will put to them exactly that question of, have we now secured this comparability with the full data package with the help of Jim -- Jose and his full team in CMC manufacturing and we believe that we're going to achieve this, because we know what the rules of engagement are.

Pascal Touchon -- President and Chief Executive Officer

Yeah. And we figure so -- the data set we have is really very robust due to the robustness of our manufacturing process performance and the minimal changes that we've made between pivotal and commercial process as Jose just explained. Does it answer your question?

Phil Nadeau -- Cowen and Company -- Analyst

Yeah. Maybe one -- just one last. What's the late -- limiting factor to the Q1 filing? Is that comparing -- is that computing the comparability analysis or is there something else that's giving?

Pascal Touchon -- President and Chief Executive Officer

Jakob?

Jakob Dupont -- Global Head, Research and Development

Yeah, so to provide these details -- so, as mentioned, we want to have the Type B CMC meeting within 60 days to solidify the issue of comparability of pivotal with the historical. So that will get taken care of. Then we have the Type B meeting for clinical, where we share the most recent data cut from ALLELE and we get the agency agreement on that. Now, that hopefully is going to solve most of the issues. Now, there may be some more more administrative issues that could get taken care of in a pre-BLA meeting. So our base case is, have these two type B meetings with the FDA, and then after that have a pre-BLA meeting that leads to a Q1 completion of the BLA filing. Now, there is an outside chance that if we secure all the issues in these two type B meetings that we may be able to have a faster submission of the BLA. But frankly, our base case is to say, we need to have these two type B meetings, then the pre-BLA meeting and then we complete the submission of the BLA.

Pascal Touchon -- President and Chief Executive Officer

And what makes us confident there is again the strengths of the data. We know the data in terms of clinical data there from the ALLELE that occurred in Q2, and are very strong. We know the robustness of a process and we have all the data needed to provide the FDA with substantially all the lots -- all the data on all the lots made by Atara. So in terms of delivering what the FDA is asking for, we feel very clear.

Phil Nadeau -- Cowen and Company -- Analyst

That's very helpful. Thanks for taking our questions.

Operator

[Operator Instructions] Our next question comes from the line of Matt Phipps with William Blair. You may proceed with your question.

Matt Phipps -- William Blair -- Analyst

Good afternoon, and thanks for taking my question. There're a few. First, was it always the plan to have a Type B clinical meeting after the Q2 data cut? It just seems like that would -- made it impossible to previously have fitted your guidance for Q3 submission -- completing that submission regardless of obviously the CMC issues. So just wondering if that is something new because again it doesn't seem like that lines up with your previous guidance on timelines outside of obviously the CMC issues.

Pascal Touchon -- President and Chief Executive Officer

Okay. So let me answer the first question on the guidance, and then you say that you have some other question. Now, I think what -- when we put the guidance in Q3, it was really based on the Type B CMC meeting that we had in Q2. And on the basis pf following that Type B CMC meeting, we could then move from pre-BLA meeting, and in the August time frame based on the data cut and then go with that with the submission of the BLA by the end of the Q3. That was basically the guidance basis there. Now what's happening is, we have the the aspects now. We have the new data on the ALLELE's data set and then we have, at the same time the data coming from this request of the FDA that will have the need to see all the manufacturer -- nearly all the manufactured lot by Atara there. So we aligned with the FDA during our recent interactions, and that was just a couple of weeks ago, where that's -- the best way forward will be to us in parallel Type B meeting on the CMC aspect, the comparability on the clinical, so you can look at the clinical data out there. And then we can have a pre-BLA that will just be the more check-the-box administrative part of the BLA meeting. So that's why it's put together with this two Type B meeting and then a pre-BLA. And in the past it was supposed to be to move directly from the Type B CMC to a pre-BLA. Jakob anything to add to that?

Jakob Dupont -- Global Head, Research and Development

No, I think that you've summed it up very well, Pascal.

Pascal Touchon -- President and Chief Executive Officer

Does it answer your question, Matt?

Matt Phipps -- William Blair -- Analyst

Yeah, I guess. It just seems like maybe there is something that's come up that's required another Type B meeting that obviously wasn't planned originally, but OK. Just wondering, you've previously said that you had about 15 lots manufactured from comparability. I wonder if that's still the number you plan to go into this Type B meeting with on the CMC side, or if there is any additional lots that will be used in the comparability.

Pascal Touchon -- President and Chief Executive Officer

Yeah. Maybe, Jakob you want to start and Jose can chime in if needed.

Jakob Dupont -- Global Head, Research and Development

Yeah, absolutely. So, Matt, I think this really speaks to how the thinking of the FDA has evolved and where we now have this clarity of guidance, because you're right. What we presented to the agency was 15 lots from each process version, which really gives us robust statistical power for that comparison. Now, for example, if you talk about a small molecule inhibitor or you talk about an antibody, generally speaking, they want about three lots to compare statistics on that. We're providing 15 of each process version. But then the agency came out and said, listen, we really want to assess all your lots for pivotal and commercial, which is really more consistent with the request that they made for allo CAR T, because...

Pascal Touchon -- President and Chief Executive Officer

Autologous.

Jakob Dupont -- Global Head, Research and Development

I'm sorry, auto CAR T. I'm sorry, auto is what I'm referring to. Where each one of those products -- each one of those cell products was an individual drug for that individual patient. So the agency wanted to see every single one of those. Now, the whole idea with allogeneic T-cell therapy is that you're able to treat many patients from your inventories. So you don't need to make one product from each patient. So we have proposed this robust statistical approach where we gave them 15 lots from each of the process versions. But the agency did fall back to this approach with us and said, we want to see all lots. And we said, OK, fine, we can deliver that with our pivotal to commercial material. And that's exactly what we're providing to them in this Type B CMC meeting, which is where we have confidence that we're going to be able to resolve this comparability issue.

Pascal Touchon -- President and Chief Executive Officer

Jose, anything you want to add?

Jose Eduardo Vidal -- Head of Quality Assurance and Process Sciences

Yes. To the question of beyond the 15 lots for -- process is very strong. In total, we're presenting now 74 lots to the agency.

Matt Phipps -- William Blair -- Analyst

Wow, OK.

Pascal Touchon -- President and Chief Executive Officer

That represents more than 95% of the total lots produced. So that's exactly what the agency wants to see. And we believe that the main rationale is that they want to confirm the robustness of manufacturing process for cell therapy and they're used to with autologous. They have habit now.

Matt Phipps -- William Blair -- Analyst

Okay. One last question on the magnetic transmission MTR data we're going to see. Is this something you've collected on every patient -- or how many patients should we expect? Because I can't recall this being something that was listed as a data being collected. And just -- will it be -- how many time points -- is it a pre-treatment and then now a 12 or 18-month follow-up? What kind of -- can you give us anything else on what to expect here?

Pascal Touchon -- President and Chief Executive Officer

AJ?

AJ Joshi -- Chief Medical Officer

Sure. So the way the MTR works is, it's really analysis you can do when you've got a good quality MRI done. So when you have a good quality MRI results, you can actually go ahead and do them to our analysis at whatever time points. So for -- as you know, for our Phase 1 study, we did 6-month and 12-month time points for EDSS. So that's the kind of thing we'll be looking to talk about in the -- with MTR. And then going forward, in the RCT, literally every single time point that an MRIs done, we'll be able to set the MTR as well.

Pascal Touchon -- President and Chief Executive Officer

And on the number of patients, that's all the patients in the Phase 1?

AJ Joshi -- Chief Medical Officer

All the patients that have a good MRI, will have a result there, in the Phase 1.

Operator

Our last question comes from the line of Ben Burnett with Stifel. You may proceed with your question.

Kelly Breeze -- Stifel -- Analyst

This is Kelly Breeze [Phonetic] on for Ben Burnett, thanks for taking our questions. We just have two quick ones. I was wondering if you guys could give any additional color on what we might see at the ATA2271 read out. The first one in terms of maybe duration of response or the number of patients we might see. And then additionally, I'm wondering -- I had a question for ATA3219, if you guys are planning on releasing any preclinical data for that. Thank you.

Pascal Touchon -- President and Chief Executive Officer

Thank you for your question. Jakob, do you want to take these questions?

Jakob Dupont -- Global Head, Research and Development

Yeah, absolutely. So thank you for the question. In terms of ATA2271, which is our autologous mesothelin CAR T program, which we're doing with Memorial Sloan-Kettering, obviously it's in the Bayer partnership as well. As we've announced, we do plan on presenting the first clinical data at a relevant meeting -- medical meeting before the end of this year. So we're certainly intending presenting that clinical data. Now, we do plan on presenting safety, efficacy, biomarker data from the study, and we have enrolled the first cohort of patients on the study with our partners at MSK. And we're currently enrolling the second cohort as well. So again, depending on data maturity and so forth, you'll see these various elements. And I do want to highlight, this program, we think, is really quite innovative and interesting because, yes, it's autologous, and it has this 1XX costimulatory domain that we've been licensed from Michel Sadelain and his team, which we think is a potentially best-in-class costimulatory domain for CAR T. And it also has the PD-1 dominant negative receptor, which provides intrinsic overcoming of the immuno-suppression of tumor PDL1. So the auto program has both of these components.

Now, obviously we're working also on the allogeneic program to 3271, and that's moving toward an IND filing, where at this point, we're leveraging our EBV T-cell platform additionally there. Now in terms of ATA3219. And we're very excited about that program. It's our first allogeneic CAR T-cell program out of the gate. It's directed against CD19. We do believe this is a best-in-class potentially program, and we did present at ASH last year in 2020, preclinical data from that 3219 program, so we can certainly -- that data is certainly available from ASH. And that also leverage this 1XX costimulatory domain from Dr. Sadelain and his team at MSK, and we're excited about that forthcoming IND submission.

Pascal, anything for else?

Pascal Touchon -- President and Chief Executive Officer

The only thing to remind everyone that this program is also we believe supported by these clinical proof of principle that was established by the team at Memorial that's showed at the Congress in 2020, that similar type of construct based on EBV T=cell from healthy donors to which they have added a CD19 CAR-T, in that case with traditional costimulatory domain. Then they treated patients with advanced B-cell malignancies, and they achieved an 83% CR rate. And that study was quite amazing and unique in the sense that they followed patients for very long time, and that CR rate was maintained over median follow-up of nearly two years. So I think that's really a very impressive data set, albeit on a small number of patients, but with long durability of response and excellent safety. So that's a nice proof of principle for what we want to achieve there to potential best-in-class, in particular having now 1XX as a costimulatory domain.

Any further questions?

Kelly Breeze -- Stifel -- Analyst

That's it from me. Thank you.

Pascal Touchon -- President and Chief Executive Officer

You're most welcome.

Operator

That concludes our question and answer session for today. [Operator Closing Remarks]

Duration: 48 minutes

Call participants:

Eric Hyllengren -- Vice President, Investor Relations and Finance

Pascal Touchon -- President and Chief Executive Officer

Jakob Dupont -- Global Head, Research and Development

AJ Joshi -- Chief Medical Officer

Jose Eduardo Vidal -- Head of Quality Assurance and Process Sciences

John Newman -- Canaccord Genuity -- Analyst

Jonathan Miller -- Evercore ISI -- Analyst

Salim Syed -- Mizuho -- Analyst

Phil Nadeau -- Cowen and Company -- Analyst

Matt Phipps -- William Blair -- Analyst

Kelly Breeze -- Stifel -- Analyst

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