Sangamo Therapeutics, inc (SGMO) Q3 2021 Earnings Call Transcript

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Sangamo Therapeutics, inc (SGMO -5.36%)
Q3 2021 Earnings Call
Nov 4, 2021, 9:15 a.m. ET

Contents:

• Prepared Remarks
• Questions and Answers
• Call Participants

Prepared Remarks:

Operator

Thank you all for standing by, and welcome to the Sangamo Third Quarter 2021 Teleconference Call. [Operator Instructions] Please also note that today's call is being recorded. I'll now turn the call over to your host, Aron Feingold, Head of Corporate Communications. Ma'am, you may now begin.

Aron Feingold -- Head of Corporate Communications and Investor Relations Officer

Good morning, and thank you for joining us today. With me this morning on this call are several members of the Sangamo executive leadership team, including Sandy Macrae, Chief Executive Officer; Mark McClung, Chief Operating Officer; Prathyusha Duraibabu, Chief Financial Officer; Jason Fontenot, Chief Scientific Officer; Rob Schott, Head of Development; and Bettina Cockroft, Chief Medical Officer. slides from our corporate presentation can be found on our website, sangamo.com, under the Investors & Media section under the Events and Presentations page. This call includes forward-looking statements regarding Sangamo's current expectations. These statements include, but are not limited to, statements relating to therapeutic and commercial potential of our product candidate; the anticipated plans and time lines of Sangamo and our collaborators for conducting clinical trials and presenting clinical data; execution of our corporate strategy; advancement of our product candidates; our revised 2021 financial guidance and other statements that are not historical facts. Actual results may differ materially from what we discuss today. These statements are subject to certain risks and uncertainties that are discussed in our filings with the SEC. Specifically, our annual report on Form 10-K for the fiscal year ended December 31, 2020, are supplemented by our quarterly report on Form 10-Q for the fiscal quarter ended September 30, 2021. The forward-looking statements stated today are made as of this date, and we undertake no duty to update such information, except as required by law. On this call, we discuss our non-GAAP operating expenses. Reconciliation of this measure to our GAAP operating expenses can be found in today's press release, which is available on our website. Now I'd like to turn the call over to our CEO, Sandy Macrae.

Alexander D. Macrae -- Chief Executive Officer, President and Director

Thank you, Aron, and good morning to everyone on the call. This is such an important moment for Sangamo as we share clinical data and business updates across several programs, demonstrating that we have three important assets in or progressing toward late stage development. Our gene therapy portfolio is advancing with accumulating safety and efficacy data in our Fabry and hemophilia A programs. Additionally, we are delighted with the preliminary proof of concept data demonstrated the clinical potential of our genome engineering zinc finger technology in sickle cell disease. This morning, we announced preliminary clinical data from our Phase one, two STAAR study, evaluating isaralgagene civaparvovec, or ST-920, our Fabry disease gene therapy product candidate. Data from this important study were evaluated from the four patients in the first two cohorts, dose cycles 0.5e13 and 1.e13 vg per kg as of the cutoff date, September 17 of this year. These encouraging results showed that for the first four patients, ST-920 was generally well tolerated. There were no treatment related adverse events higher than grade one and no treatment related serious adverse events. No patients experienced liver enzyme elevations or required steroid treatment.

All four patients exhibited above-normal alpha-gal activity which were maintained for up to one year for the first patient treated and through 14 weeks from most recently treated patients. Levels range from two to 15, fold above normal levels at last measurement as of the cutoff date. Interestingly, the first three patients dose reported improvements in ability to select a primary and common Fabry disease symptom that limits exercise tolerance for the patient. ERT withdrawal is now complete for one patient and is planned for the other patient on ERT based on the stability of their alpha-gal activity following treatment. Based on these data, we have initiated Phase three planning. The fifth patient in the study, who is the first patient in the third dose cohort had 3.e13 was recently dosed. The sixth patient is currently in screening also for the third dose cohort, and we expect to provide updated results throughout 2022 and present these data at a medical meeting. This morning, we also announced that preliminary proof of concept results from the Phase one, two PRECIZN study of SAR445136, an investigational zinc finger nuclease gene edited cell therapy in patients with sickle cell disease will be presented at ASH. This program is partnered with our friends at Sanofi. The data in the abstract shows that as of June 25, 2021, cutoff date, none of the four patients treated require blood transfusion post-engraftment through 65 weeks of follow-up for the longest treated patients. The Board treated patients all experienced increases in total hemoglobin, fetal hemoglobin and percent F cells. No adverse events or serious adverse events related to treatment were reported as the cutoff date. Further data will be provided in a poster presentation attached on December 12. Sangamo and Sanofi are continue to advance the sickle cell disease program. The company's recently obtained manufacturing requirements guidance from the FDA in preparation for potential further clinical studies. Separately, we and Sanofi made the business decision to cease development for the beta thalassemia indication and allowing us to focus resources on the sickle cell disease program. Moving now on to our hemophilia A program partnered with Pfizer. We announced this morning the updated follow-up results from the Phase one, two Alta study of giroctocogene fitelparvovec will be presented at ASH. For the four patients in the highest dose cohort who have been followed for at least 104 weeks as of May 19, 2021 cutoff, mean factor eight activity was 30.9% at week 104, as measured by chromogenic assay. In this cohort, annualized bleeding rate was 0 for the first year after treatment and 0.9% throughout total duration of follow-up. As demonstrated in this study, the gene therapy was generally well tolerated in patients with severe hemophilia A. Further data will be provided in a poster presentation at ASH on December 12, 2021.

We and Pfizer also announced that some of the patients treated to date in the Phase three AFFINE trial experienced Factor eight levels greater than 150% following treatment. To date, none of these patients have experienced thrombotic events, and some have been treated with direct oral anticoagulants to reduce thrombotic risk. Out of an abundance of caution, Pfizer voluntary pause screening and dosing of patients in the trial in order to implement a protocol amendment, which will provide guidelines for clinical management of elevated Factor eight levels. On November 3, Pfizer respond the FDA has put this trial on clinical hold. Pfizer and Sangamo are committed to resuming patient dosing as soon as possible. We continue to believe that this gene therapy will represent an important treatment option for patients with hemophilia A. The next step is to share the proposed protocol amendment with health authorities and respond to the clinical hold, after which the companies will be able to provide updated timing for the trial. Turning now to our kidney transplant program. We have now enrolled the first patient in our Phase one, two STEADFAST study evaluating TX200, our wholly owned autologous CAR-Treg cell therapy candidate. We believe that this is the first in human CAR-Treg study and that this field is going with much excitement as a promising approach for challenging autoimmune conditions. In this study, similar to other genetically engineered cell therapy approaches, patients will undergo a procedure from which their Treg cells will be isolated, engineered and then cryopreserved.

The HLA-A2 negative patient will subsequently undergo kidney transplant and following a recovery period, will receive their personalized TX200 therapy. We expect to dose the first two patients in the study by the middle of 2022, following their kidney transplants. We continue to open sites and screen patients. We believe this proof of concept study may represent an important treatment for patients undergoing renal transplant and will help us understand CAR-Treg biology in humans as well as advanced process development knowledge. We hope that this study establishes the foundation for a portfolio of wholly owned CAR-Treg therapies for autoimmune indications. Finally, I'm delighted to share that Mark McCann has been appointed as Sangamo's Chief Operating Officer effective November 1. Mark's expanded role as COO, is an important organizational step for Sangamo, which will support the multiple advancing wholly owned and partnered programs. We look forward to Mark's continued leadership as we continue to build the capabilities to bring genomic medicines to patients and to the marketplace. Everyone at Sangamo is thrilled with this clinical momentum, and we look forward to presenting updated Fabry results throughout 2022 as well as working with our collaboration partners and investigators to present the ASH data in December. And with that, I'll turn the call over to Prathyusha for a financial update. Prathyusha?

Prathyusha Duraibabu -- Senior Vice President, Chief Financial Officer and Principal Accounting Officer

Thank you, Sandy, and good morning. Our financial results for this quarter are available in the press release issued this morning, which can also be found on our website. I want to reiterate that this is an exciting moment for us as a company. And this quarter, we continue to invest in the advancement of our clinical programs, including Fabry and TX200, our preclinical research pipeline and our in house manufacturing capabilities. With approximately $590 million in cash, cash equivalents and marketable securities at the end of the quarter, we believe that our balance sheet remains strong. Turning to 2021 full year guidance. We expect non-GAAP operating expenses to be between $265 million to $275 million for the year, which is within the range of the guidance that we have previously provided. This range excludes estimated non cash stock-based compensation expense of approximately $35 million. I will now turn the call back to Sandy for closing remarks.

Alexander D. Macrae -- Chief Executive Officer, President and Director

Thank you, Prathyusha. We are very excited about these clinical data readouts. We show the advancement of our first generation genomic medicine pipeline with traditional gene therapy and autologous cell therapy. These programs potentially pave the way for our next generation focus on genome regulation and allogeneic CAR-Treg cell therapy, where we have a robust preclinical pipeline in neurological and autoimmune diseases, respectively. We're delighted with the positive momentum and look forward to updating you in the near term about several potential catalysts, including presentation at ASH for patient sickle cell disease Phase one, two data, presentation at ASH of two year Phase one, two hemophilia data. And additionally, we'll provide a timing update for the Phase three trial once the proposed protocol amendment in response to the hold is shared with health authorities. Dosing of the six patients and updated Fabry Phase one, two data presentations throughout 2022, including at a medical meeting, dosing of the first two patients in the STEADFAST Phase one or two study by the middle of 2022 and completion of our in house cell therapy manufacturing facility in our Valbonne France location following the completion of our in house manufacturing facility in our Brisbane California headquarters this past quarter. So we'll now turn it over to the operator to open the line for questions.

Questions and Answers:

Operator

[Operator Instructions] Speakers first question is from the line of Aspen Mori of Bank of America.

Aspen Mori -- Bank of America -- Analyst

So on Fabry, I think you previously hadn't expected to share some of the enzyme replacement therapy withdrawal data in this year end release. It's good to see that time frame seems to have maybe a bit faster than expected. But with that in mind, I guess, is there any patterns you're seeing in the time frame it takes from getting from the dose of ST-920 to removal of that therapy? And it also appears that maybe the patient for kind of got to that milestone a little quicker than Patient 1, who had a longer follow-up. Just want to see if there's anything you're seeing there to explain that?

Alexander D. Macrae -- Chief Executive Officer, President and Director

So thank you for your question. I think what I'm hearing, you're asking about is about ERT withdrawal. So we thought it was important to see, to truly understand the effect duration. And we've been very pleased that over the course of a year in the longest treated patients, there's been a consistency of effect. And we then have discussions with the investigators. And at the appropriate point for them and for their patient, they will withdraw treatment and the first patient was only withdrawn very recently, and the second one is planned to be withdrawn this year. And so we will share that data at an appropriate time.

Aspen Mori -- Bank of America -- Analyst

Okay. And then I have one more on Fabry. Are there any trends you're seeing among patients one and four for that signal maybe what's driving better alpha-Gal A response than you're seeing with patients two and three? I think two and three might have had lower baseline GB3, but if there's anything you could point to that would help out there?

Alexander D. Macrae -- Chief Executive Officer, President and Director

Well, so there's only four patients, so it's very difficult to say anything specific. It is notable though that patients one and four are on ERT and patients two and three are not. And it may be that there is some additional effect from the ERT that is leading to that effect. But I think that is only speculation, and we need to dose more patients to understand it.

Operator

Next question is from Yanan Zhu of Wells Fargo.

Yanan Zhu -- Wells Fargo -- Analyst

I have a question on Fabry and maybe also additional questions on other updates. But Fabry, could you, Sandy, comment on the dose response here? And also, I think for patient two, there was a increase in enzyme levels above normal, but the substrate levels seems to be flat. So could you shed some light on that finding?

Alexander D. Macrae -- Chief Executive Officer, President and Director

So it's a good question. And I think this has been something that's been consistently seen across all of the research into Fabry disease, if the substrate levels are low, they don't change in the treatment period. But Bettina, do you have thoughts on this on the dose response that we've seen?

Bettina M. Cockroft -- Senior Vice President and Chief Medical Officer

Thank you, Sandy. So as Sandy mentioned, we have now dosed two patients in cohort one and two patients in Cohort two. This is still a small sample size. This needs to be emphasized at this point in time. But regarding the levels of life of Gb3, for sure, in three of the four patients, those are Gb3 levels started off low and as Sandy mentioned, across programs, it has been seen that these remain stable if they are low to start with. If you look at patient three, this patient like Gb3 level start off high and the levels of lyso Gb3 were reduced by about 40% within 10 weeks after dosing, and this reduction was maintained through 32 weeks. So at this point in time, with such a small sample size, it is really difficult to talk about those relationships. I would say that throughout 2022, we anticipate to share more data and that data will also be shared at a medical meeting. So there will be more granularity and data to come.

Alexander D. Macrae -- Chief Executive Officer, President and Director

But what I want you to take away is how excited we are by this because all four patients are above the normal physiological level. All four patients have shown consistency of response in the time that they've been observed. And three of the four patients are already reporting patient effects are very encouraging about the effect of the drug, and we are already into the next higher cohort. And as Bettina says, we'll talk about this next year.

Yanan Zhu -- Wells Fargo -- Analyst

Great. And on the clinical hold, for the hemophilia A collaborated hemophilia A program, I was wondering how high is the Factor eight level? I thought we had seen like 200% from other studies. So could you shed some light on the rationale for that clinical hold? And lastly, a question on BIVV003, a very quick one that is at ASH, would we see VOC data for the treated patients?

Alexander D. Macrae -- Chief Executive Officer, President and Director

So I'm going to pass the question on hemophilia to Rob. Rob, can you talk to this?

Robert J. Schott -- Senior Vice President and Head of Development

Yes. We have seen elevations of Factor eight greater than 150% in some patients. This is an ongoing Phase three trial. So we're not getting very specific with the data around this. There were no venous thromboembolic events associated with these elevated levels and the decision to voluntarily pause the trial was out of an abundance of caution. And as anticipated, the FDA followed through with a clinical hold that was, we were notified of that late yesterday. It's our plan to, with Pfizer to submit a protocol amendment and have a discussion with the agency and resume the trial when it is appropriate to do so.

Alexander D. Macrae -- Chief Executive Officer, President and Director

And regarding sickle cell disease, we have, we'll show the full data set at ASH in December.

Operator

Next question is from Luca Issi of RBC Capital.

Luca Issi -- RBC Capital -- Analyst

Congrats on the progress. Maybe on Fabry disease exciting early proof of concept. I'm wondering if you can comment on how you're thinking about the Phase, study design? On hemophilia A, maybe if you can provide any additional color on the protocol amendment that you're thinking about to minimize the risk going forward? And then maybe on, can you just expand a little bit more on the rationale behind the decision to terminate a program?

Alexander D. Macrae -- Chief Executive Officer, President and Director

Good news. So it's so exciting to be talking about Phase three design because we are very pleased with the results. But we need to see the the results of the third cohort to really be able to understand which dose we're taking forward. And we design the study. But I can reassure you that planning and the full energy behind the Phase three has already started on these programs. Let me then pass the hemophilia question to Rob and the Peter tomorrow.

Robert J. Schott -- Senior Vice President and Head of Development

Yes. With regard to the protocol amendment, we're not disclosing any of the specifics of the protocol amendment at this time. But the protocol amendment is being considered and will be submitted promptly and in discussion with the agency in response to the clinical.

Alexander D. Macrae -- Chief Executive Officer, President and Director

And the current plan is to find the best way to guide management of any patient that has a higher level.

Robert J. Schott -- Senior Vice President and Head of Development

Yes. So it will be monitoring and management of the patients with levels of Factor eight that are greater than 150%.

Alexander D. Macrae -- Chief Executive Officer, President and Director

But we feel it important to restate every time that conversation comes up that no patient has come to on, there have been no adverse events related to this. And this is an abundance of caution, and I think a correct abundance of caution because this is a gene therapy that we need to take very seriously and do the best for the patients. Mark?

D. Mark McClung -- Executive Vice President and Chief Business Officer

Yes. So in terms of the beta-thal decision, it was really a business decision that we took alongside our partners at Sanofi just due to the timing and relative to where the competitive set lies in terms of their development. We felt that it is important to really focus our effort and our resources solely on sickle cell disease

Alexander D. Macrae -- Chief Executive Officer, President and Director

And driving forward together.

Operator

Next question is from Maury Raycroft of Jefferies.

Maury Raycroft -- Jefferies -- Analyst

Congrats on the update today. For Fabry, just wondering if you can talk more about the alpha-Gal data being two to 15-fold higher than normal. It seems higher than competitor data at month 12 that showed about five to six fold higher. I guess what's the best way to contextualize your data versus competitors? And how could this translate to kidney substrate reduction.

Alexander D. Macrae -- Chief Executive Officer, President and Director

Thank you, Maury. Bettina, do you want to talk about Fabry?

Bettina M. Cockroft -- Senior Vice President and Chief Medical Officer

Sure. Thank you, Sandy. So in terms of the alpha-Gal data, we're obviously very excited to see the super physiologic alpha-gal expression that we are seeing with all four patients. I think at this point, it is early to compare and probably not the right place to do comparisons across programs. We look forward to sharing more granularity on this data at an upcoming meeting in 2022. So that also goes to any additional data related to kidney substrate.

Alexander D. Macrae -- Chief Executive Officer, President and Director

You can imagine, though, that having seen efficacy at the two initial cohorts and moving into a third higher cohort, it gives us enormous energy that this is going to be a medicine that will be useful for patients with Fabry. It really is compelling data early as it is, we find a compelling data.

Robert J. Schott -- Senior Vice President and Head of Development

And I would add that our priority, we had targeted super physiologic expressions of alpha-Gal A and plasma to drive clearance from tissue. So this is a desired effect of what we're seeing.

Maury Raycroft -- Jefferies -- Analyst

Got it. That's all helpful. And maybe just one follow-up. If you can compare and contrast the Fabry observations and gene expression and dose with your hemophilia gene therapy program? Maybe if you can talk more about that?

Alexander D. Macrae -- Chief Executive Officer, President and Director

That's a good question. I mean we are fortunate that we used AAV6 now in several programs, and we understand the safety of it. And across all of the programs, we've had very few adverse events. In addition, if you look at the point at which there's an inflection of efficacy, it's about the one to 3.e13 in hemophilia. And it's even earlier than that in the Fabry disease program. Other than that, we're very pleased with the safety and efficacy we've now seen in our two gene therapy programs.

Operator

Next question is from the Nicole Germino, Truist Securities.

Nicole Germino -- Truist Securities -- Analyst

So I dialed in a little bit late, and I might have missed some of the opening remarks, so I apologize if my questions were already addressed. But for Fabry, can you talk about how the primary symptoms have improved over time from baseline? And any color on cardiac function? And for hem A, how long some infusion did these excursions happen? And how long are Factor seven level being assessed going forward to monitor?

Alexander D. Macrae -- Chief Executive Officer, President and Director

So your line is is a little unclear. So let me see, read back to see the your question, it's about the patient symptoms in Fabry and it's about how we manage the patients in hemophilia, is that correct?

Nicole Germino -- Truist Securities -- Analyst

I guess. And how long, for hemophilia, how long from the infusion did these persons happen?

Alexander D. Macrae -- Chief Executive Officer, President and Director

So Bettina, can you say what we know about the patient-reported symptoms in Fabry, please?

Bettina M. Cockroft -- Senior Vice President and Chief Medical Officer

Yes, of course. So as a reminder, again, I'd like to emphasize this is early data that we're sharing early preliminary data. The patients in cohort two, three of the four patients had an hidrosis, reported at baseline. And some of these patients, these three patients have reported improvement in sweating or preparation, which is a favorable outcome for patients in the time period over the course of the study that we have seen so far. One of the patients also had seen stabilization of target structure on serial assessment on imaging. So these are preliminary reports that we are gathering. And as I mentioned before, we will be sharing more information over the course of next year of some of these details.

Robert J. Schott -- Senior Vice President and Head of Development

I'd like to add that if you look at the totality of the data, including the patient observations that were related to the investigators, the alpha Gal expression, the adverse events that all of the data are all pointing in a favorable direction. So we would like you to look at the data in its totality, not just each individual component.

Nicole Germino -- Truist Securities -- Analyst

Great. And then for heme A, how long from the infusion did the excretions happen?

Robert J. Schott -- Senior Vice President and Head of Development

This is an ongoing Phase three trial. So we aren't disclosing the specifics around the data. We want to keep that Phase three trial protected because it's a potential registration trial.

Operator

Next question is from Gena Wang of Barclays.

Gena Wang -- Barclays -- Analyst

This Tom for Gina. So for the Fabry, just one question with the dosing and the alpha-Gal enzyme level. Do you plan to dose higher, depending on the data rate? And what is the mango of that outgo level in the serum? Is the current super physiological level enough in your? And how about the alpha-Gal enzyme level changed after the patient who withdraw from the ERT? And, for the hemo A.

Alexander D. Macrae -- Chief Executive Officer, President and Director

Well, let, can we just first, so as we make sure we cover all your questions. We've never said it must be this for alpha-Gal Because this is the first time that people have really done gene therapy in Fabry disease. And so there isn't a definitive level. We've always thought it had to be better than normal physiological levels. And we're pleased to the patients both on ERT and off ERT are at that level. And now what we're doing is withdrawing the ERT and seeing where the levels provided by the gene therapy in the liver level out. And until we do that experiment, we really won't understand this fully. We are also dosing at 3.e13, which is three times higher than the current dose. And once we see that data in its totality, we will be able to decide which dose to take forward into Phase III. But we felt that the first two cohorts were so compelling, as Rob says, with the alpha-Gal with the patient safety with the patient-related outcomes that came spontaneously from patients talking to the investigator about things that have been, that are important to them, like ability to exercise now sweat that we felt that this data was exciting and compelling and wanted to share it with the broader community.

Analyst

Okay. Great. That's very helpful. And maybe just a quick follow-up on the Fabry that you comment that you will share additional data, including the function data in the 2022 meeting? And will that be included like Gb3 kidney inclusion or it will be EGFR like the filtration function measurement? Can you help us to set an expectation for that?

Alexander D. Macrae -- Chief Executive Officer, President and Director

It's unlikely that we'll be sharing renal biopsy data in '22. There's a, the patient would undergo an initial biopsy and then some months later, a second one. So that data is unlikely to be available in 2022.

Analyst

Okay. Okay. And for the hemo A, so we know that there will be amendment. And other than that, do you expect any additional steps that require in order to remove the clinical hold? Or the implementation of the oral anti coagulate will be on only one that will build?

Alexander D. Macrae -- Chief Executive Officer, President and Director

I have enormous confidence in our colleagues at Pfizer. They're putting together an amendment that puts patients first and make sure that the patients always remains safe and then they will discuss that and present it to the agency. And hopefully, we'll be able to move forward with this trial. As Pfizer have said, over 50% of the patients have been involved now and they had pre-study to collect the patients to have them ready to go into the trial. So we think this will move forward and are sure that Pfizer is doing the right thing.

Operator

Next question is from Ritu Baral of Cowen.

Ritu Baral -- Cowen -- Analyst

As part of this Phase three, what other clinical, I guess, a clinical quality of life or patient reported symptomatology are you capturing? Sandy, you mentioned improvement in sweating. Are there other things that are being proactively asked clinical symptomatology wise? And then can you talk at all about sort of the curve of expression that you're seeing, like for patient one, that 15-fold at week 52. Can you confirm that that's like the top expression that you've seen and for patient four that you're sort of continuing on your way up and anything you can say about the first?

Alexander D. Macrae -- Chief Executive Officer, President and Director

Okay. So we measure a whole slew of things, including formal patient-related outcomes. We want to be very clear. This was spontaneous, patient spontaneously talking to the investigator to tell them of their, of the changes that they've known and the investigator felt compelled to tell us because it was important. We will measure this going on in the Phase three and because it's not just about the enzyme what's important is what's important to the patient is things like the neuropathic like pain that they have, it's about the sweating, it's about the quality of their life and their energy. And so we want to capture all these things. The second question, I think, that you're asking us about duration. That's very pleasing to us because this is a solution we want for as long as possible for those patients. And in all of the patients, after, once it gets to its plateau level, it has remained at that level throughout the duration of the study. And we will continue to follow these patients and report how the, hopefully, the continued duration of effect.

Ritu Baral -- Cowen -- Analyst

Got it. And just given the change in the, I guess, the regulatory landscape in Fabry over the last 12 months or so, are there any plans to potentially add a biopsy to this study? Or are you, is that going to be reserved for the next study? Can you biopsy?

Alexander D. Macrae -- Chief Executive Officer, President and Director

We have plans for biopsy in this study. It's just that the results will not be available within the 2022 phase. We've always said that we would not do the biopsy in their initial patients until we saw that the medicine was effective. And now we see the medicines affected biopsies will be part of the routine of the study.

Ritu Baral -- Cowen -- Analyst

Got it. Okay. So maybe not the biopsy from these patients that maybe the fifth and sixth patients of highest dose, is that the plan?

Alexander D. Macrae -- Chief Executive Officer, President and Director

So the first four patients did not have renal biopsy. And future patients will as part of the study protocol.

Operator

Next question is from Ben Burnett of Stifel.

Ben Burnett -- Stifel -- Analyst

I will echo my congratulations on the Fabry disease data. I did want to ask a couple of questions around this. The first one I would also agree with some of the others on the call. It seems like the enzyme activity is quite good, at least relative to competitors. But I guess just curious that the impact on lyso-Gb3 just wasn't more profound, specifically on patients one, two and four. I guess how, what is your interpretation of those data? And how representative is lyso-Gb3 in the plasma to what's happening inside of cells?

Alexander D. Macrae -- Chief Executive Officer, President and Director

Question. And until we biopsy, we won't have that direct correlation. I'll say again, in all of the Fabry trials from each of our competitors and us, patients who have low lyso-Gb3 don't go lower. If it's already very low, it's hard to make it go lower and that's across all of the trials. And even in the trials that have done Gb3, even in the trial, for example, who showed a reduction in GBC in the kidney, they also showed that effect that it had to be a high lyso-Gb3 to show a reduction in the plasma. It's a very different system that we're producing here. And we think this is what patients want. They want a one time injection that is safe, that is effective at producing alpha-gal and is effective at producing over a long period of time. And that they notice a benefit, and we're already having indications that that's what we've seen. Now we need to go to the next higher dose and hopefully show even more benefit. And then put all that data together and decide on the full design of the study for Phase three and get this medicine to patients as soon as possible. But we are very pleased with the safety, the efficacy, the consistency and the patient benefit that we've seen so far.

Ben Burnett -- Stifel -- Analyst

Understood. Okay. That's helpful. And if I could just ask one sort of clarifying question on patient four. Alpha-Gal activity at week 14, you show an assessment that looks, I think, really good. But was this assessment made after they were weaned off of enzyme replacement therapy? Or was that prior to that?

Alexander D. Macrae -- Chief Executive Officer, President and Director

Bettina, can you clarify this?

Bettina M. Cockroft -- Senior Vice President and Chief Medical Officer

Absolutely. So patient number four has only been withdrawn from ERT very recently and after the cutoff data for what you're seeing on these slides that we have posted on our corporate website. So the data you're seeing is with the patients still on ERT. And just to clarify, all the data points are at trough ERP level. So dosing was prior to the ERT infusion. So the ERT withdrawal will have been after this data cut.

Alexander D. Macrae -- Chief Executive Officer, President and Director

It's part of the reason that this therapy is, I think, offers a better solution than ERT is, ERT has a very rapid Cmax and then it declines quickly. But we wanted to be particularly careful and therefore, we measure the trough level usually out day 14 after the ERT at the very last point before the patient had their next dose of ERT to make sure there was no residual enzyme in the plasma. And that's something I think we all, in all the different studies from all the different companies need to be careful about is making sure that the trough is the trough.

Operator

Speakers, we have time for one more question from Andreas Argyrides of Wedbush Securities.

Andreas Argyrides -- Wedbush Securities -- Analyst

Let me also reiterate our congrats on this early encouraging data. Yes. So for Fabry, just a quick one on the pre-existing antibodies and your thoughts around any potential impact that may have? And then on the hemophilia A, does the protocol amendment restart the time for the ABR data?

Alexander D. Macrae -- Chief Executive Officer, President and Director

So let me answer the second one and then pass the antibodies to Bettina. Why this had to be treated seriously? Was these are patients in gene therapy? So when they get the medicine, it stays in their body, even if the trial is paused. And so we and Pfizer will continue to collect data from the patients even though the recruitment into is paused, there's still information about prolongation of effect and safety of the medicine being collected by Pfizer. So it's unusual compared to a pause trial where the patient stops taking the medicine. The medicine is still there and continuing to have benefit for the patient, we hope. Bettina, the antibodies?

Bettina M. Cockroft -- Senior Vice President and Chief Medical Officer

Yes. For the antibodies, so I think what is important to emphasize is this is early data on four patients, and it is early to make inferences as to whether antibodies and to what degree antibodies are having an effect on these patients. We need to bear in mind that two of these patients are on ERT, two or not. There is a lot of variability in the data at this point in time. So we look forward to seeing more data coming out from our next cohort, cohort three, and being able to assess that impact in a better manner.

Alexander D. Macrae -- Chief Executive Officer, President and Director

And, but we haven't seen anything, any correlation up to now.

Bettina M. Cockroft -- Senior Vice President and Chief Medical Officer

At this point in time, that would be difficult to say.

Operator

Thank you, participants. I'll now turn the call back over to Aron Feingold, for closing remarks.

Aron Feingold -- Head of Corporate Communications and Investor Relations Officer

Thank you once again for joining us today and for your questions. We look forward to keeping you updated on our future developments.

Operator

[Operator Closing Remarks]

Duration: 45 minutes

Call participants:

Aron Feingold -- Head of Corporate Communications and Investor Relations Officer

Alexander D. Macrae -- Chief Executive Officer, President and Director

Prathyusha Duraibabu -- Senior Vice President, Chief Financial Officer and Principal Accounting Officer

Bettina M. Cockroft -- Senior Vice President and Chief Medical Officer

Robert J. Schott -- Senior Vice President and Head of Development

D. Mark McClung -- Executive Vice President and Chief Business Officer

Aspen Mori -- Bank of America -- Analyst

Yanan Zhu -- Wells Fargo -- Analyst

Luca Issi -- RBC Capital -- Analyst

Maury Raycroft -- Jefferies -- Analyst

Nicole Germino -- Truist Securities -- Analyst

Gena Wang -- Barclays -- Analyst

Analyst

Ritu Baral -- Cowen -- Analyst

Ben Burnett -- Stifel -- Analyst

Andreas Argyrides -- Wedbush Securities -- Analyst

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