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MacroGenics, Inc.
4/29/2021
Good afternoon. We will begin the Macrogenics 2021 First Quarter Corporate Progress and Financial Results Conference call in just a moment. All participants are in a listen-only mode at the moment, and we will conduct a question and answer session at the conclusion of the call. At this point, I will turn the call over to Jim Carroll, Senior Vice President, Chief Financial Officer at Macrogenics.
Thank you, Operator. Good afternoon, and welcome to Macrogenics Conference call to discuss our First Quarter 2021 Financial and Operational Results. For anyone who has not had the chance to review these results, we issued a press release this afternoon outlining today's announcements, which is available under the Investors tab on our website at macrogenics.com. You may also listen to this conference call via webcast on our website, where it will be archived for 30 days beginning approximately two hours after the call is completed. I would like to alert listeners that today's discussion will include statements about the company's future expectations, plans, and prospects that constitute forward-looking statements for purposes of the safe harbor provision under this Private Securities Litigation Reform Act of 1995. Actual results may differ materially from those indicated by these forward-looking statements as a result of various important factors, including those discussed in the risk factors section of our annual, quarterly, and current report filed with the SEC. In addition, any forward-looking statements represent our views only as of today and should not be relied upon as representing our views as of any subsequent date. While we may elect to update these forward-looking statements at some point in the future, we specifically disclaim any obligation to do so, even if our views change except to the extent required by applicable law. And now I'd like to turn the call over to Dr. Scott Koenig, President and Chief Executive Officer of Macrogenics.
Thank you, Jim. I'd like to welcome everyone participating via conference call and webcast today. This afternoon I will provide key highlights from our clinical programs. But before I do so, let me first turn the call back to Jim, who will review our financial results for the first quarter.
Thank you, Scott. This afternoon, Macrogenics reported financial results for the quarter ended March 31, 2021, which highlight our financial position as well as our recent progress. As described in our release this afternoon, Macrogenics' total revenue, consisting primarily of revenue from collaborative agreements, was $16.9 million for the quarter ended March 31, 2021, including $0.9 million net sales of Margenza, which launched in mid-March, compared to total revenue of $13.7 million for the quarter ended March 31, 2020. Revenue recognized during the quarter ended March 31, 2021, included a $10 million milestone related to development progress of Retifanlimab outside the U.S. under our exclusive global collaboration and license agreement with Insight. Our research and development expenses were $53.1 million for the quarter ended March 31, 2021, compared to $48.9 million for the quarter ended March 31, 2020. This increase was primarily due to higher expenses related to fletituzumab, MGCO-18, MGD-019, and preclinical projects, partially offset by a decrease in development and manufacturing costs for retifamilumab. Our selling, general, and administrative expenses were $15 million for the quarter ended March 31, 2021, compared to $10.2 million for the quarter ended March 31, 2020. This increase was primarily due to Macrogenic's 50% share of sales and marketing costs related to Margenza pre-launch and launch activities, as per our agreement with Iversana. Our net loss was $51.3 million for the quarter ended March 31, 2021, compared to a net loss of $44.7 million for the quarter ended March 31, 2020. Our cash, cash equivalents, and marketable securities balance as of March 31, 2021 was $343.2 million compared to $272.5 million as of December 31, 2020. During the quarter ended March 31, 2021, we sold 3.62 million shares through our at-the-market or ATM facility at an average price per share of $27.60, raising net proceeds of $98.2 million. As this fully depleted our previously filed $100 million ATM facility, today we refresh the ATM by filing a $200 million prospectus supplement to our SHELP registration statement. Finally, in terms of our cash runway, I will remind listeners that there are two PDUFA target action dates scheduled for July of this year relating to BLA's for both metathalamab and tiplizumab. For cash budgeting purposes, we continue to discount both milestones as we have no control over them. Even with this discounting, we anticipate that our cash, cash equivalents, and marketable securities as of March 31, 2021, combined with anticipated and potential collaboration payments, should enable us to fund our operations through 2023, assuming the company's programs and collaborations advance as currently contemplated. And now I'll turn the call back to Scott.
Thank you, Jim. With the recent launch and commercialization of Margenza, we are delivering on our vision to provide potentially life-changing therapeutics to patients with cancer. We are well-positioned to advance this mission as the growing body of data emerges from our deep pipeline of clinical and preclinical product candidates. We are particularly excited about the multiple ongoing registrational or potentially registration-enabling studies including flotatuzumab and AML, and margituximab and gastric cancer. These are in addition to two PDUFA outcomes related to teplizumab and retifanilamab in July. And finally, we know many of you are eagerly awaiting clinical data from multiple dose expansion or proof-of-concept studies, including from MGC-018, tebotelemab, and MGD-019. With that backdrop, let me use this time to walk you through updates on our portfolio of eight clinical molecules. First, let me provide an update on margituximab. As Jim and I both mentioned, Margenza was launched in mid-March in coordination with our commercial partner, Evasana. As a reminder, Margenza is approved in combination with chemotherapy for the treatment of adult patients with metastatic HER2-positive breast cancer who have received two or more prior anti-HER2 regimens, at least one of which was for metastatic disease. Margenza was recently included in NCCN guidelines. As I mentioned on our last quarterly call, we have modest expectations for Margenza sales given competitive realities that have taken place in the HER2-positive breast cancer market, including multiple new approvals, which is great for patients. Owing to these recent changes in the market and the abbreviated sales history, we don't expect to provide Margensa sales guidance until later this year when we have a better sense of uptake by oncologists. Finally, with regard to margituximab and metastatic breast cancer, as you may recall, the Phase III SOFIA trial is still ongoing for overall survival. Based on the current accrual rate of OS events in the ongoing Phase III SOFIA metastatic breast cancer study that supported approval by the FDA, we now anticipate completing the final analysis of OS data based on accrual of the 385th OS event by the end of the third quarter. Beyond breast cancer, we are evaluating margituximab in the Phase 2-3 mahogany study in patients with advanced gastric and gastroesophageal junction cancer. This trial consists of two modules designed to evaluate margituximab as an investigational agent in combination with a checkpoint inhibitor with or without chemotherapy as a potential first-line treatment for patients with advanced or metastatic HER2-positive gastric or gastroesophageal junction junction cancer. As previously indicated, we submitted a placeholder abstract on margituximab and gastric cancer in mid-February for our first half medical meeting. The submitted abstract included initial safety and efficacy data relating to 24 resist-available mahogany module A patients who were treated with a combination of retofenilamab, an investigational anti-PD1 antibody, and margituximab. The abstract was accepted by ASCO. However, in consultation with the study's lead investigator, whose preference is to present updated results when most of the 40 enrolled patients will have been evaluated radiographically by central review, we and the lead investigator withdrew the ASCO abstract and we will submit an updated one to ESMO. Module B, which is evaluating margituximab plus either of two of macrogenic's checkpoint inhibitor molecules in combination with chemotherapy compared to standard of care therapy of trastuzumab with chemotherapy in patients with HER2-positive tumors irrespective of PD-L1 expression is currently ongoing enrollment in coordination with our regional partner in Greater China, XyLab. Module B is expected to continue enrollment through 2021. Next, let me discuss Flotituzumab, our investigational bispecific CD123 by CD3 DART molecule. We continue to enroll the single-arm registrational clinical study to evaluate Flotituzumab in up to 200 patients with primary induction failure or early relapse AML. We anticipate providing further updates on the clinical development of Flotituzumab in late 2021 and completing full enrollment of the study in 2022. I'll next discuss MGCO18, our investigational antibody drug conjugate designed to deliver a DNA-oscillating durochromycin cytotoxic payload to cells that express B7H3. As you saw in ASCO's release of abstract titles yesterday, we plan to provide an update on MGC 018 Phase I clinical data at the upcoming conference via poster presentation. When the ASCO abstract comes out in mid-May, you will see that as of January 21st, 2021 data cut off ahead of the February 17th submission deadline, we had enrolled the four MIG per kid cohort, which included three melanoma patients. Based on preliminary data from these patients, we added a melanoma expansion cohort to the phase one study. In addition, although we did not enroll any squamous cell carcinoma of the head and neck patients in dose escalation, based on preclinical PDX mouse model data presented at AACR and other available data, we also added a squamous cell carcinoma of head and neck dose expansion cohort with both melanoma and squamous cell carcinoma of the head and neck patients to be dosed at three mgs per kig. We expect to fully enroll the 40 metastatic castration-resistant prostate cancer patients as well as the 20 non-small cell lung cancer patients by mid-year and the 20 triple negative breast cancer patients later this year. With regard to the metastatic castration-resistant prostate cancer expansion cohort, as of today, we have enrolled more than 20 patients. All but two of them remain on therapy and we are encouraged by the PSA data we've seen to date. Again, with appropriate caveats here, this is early preliminary data. We have too few scans from any of the cohort expansion patients at this time to draw any conclusions. We look forward to presenting the MGC 018 data at ASCO. Another of our investigational molecules exploiting the overexpression of B7H3 in solid tumors is inoblutuzumab, an FC-engineered antibody created using our FC optimization platform. In March, we initiated a combination study of inoblutuzumab in a chemotherapy-free regimen in front-line squamous cell carcinoma of the head and neck with either tebotelemab for patients who are PD-L1 negative or with retofanilamab in patients who are PD-L1 positive. Next up, Tebotelemab is our investigational bispecific PD-1 by LAG-3 DAR molecule. We are evaluating tebotelemab in a phase one dose expansion study as both monotherapy in several tumor types, as well as in combination study with margituximab. We expect to provide updates on the next stage of development for tebotelemab later this year. Our partner, XyLab, has the right to develop and commercialize tebotelemab in mainland China, Hong Kong, Macau, and Taiwan, and currently has multiple ongoing monotherapy and combination studies of Teva-Telemat. Let me next discuss MGD019, our investigational bispecific checkpoint DART molecule that targets PD-1 and CTLA-4. Our phase one dose expansion study is initially evaluating patients with microsatellite-stable colorectal cancer and checkpoint IV non-small cell lung cancer at the recommended phase 2 dose of 6 mg per kid. We are in the process of adding expansion cohorts with metastatic castration-resistant prostate cancer patients and with melanoma patients. Let me next turn to retifanilamab. The investigational anti-PD-1 antibody that we licensed to INSIGHT is INC-MGA0012. The FDA accepted for priority review INSIGHT's BLA-Furetifanilamab as a potential treatment for adult patients with locally advanced or metastatic squamous cell carcinoma of the anal canal who have progressed on or who are intolerant of platinum-based chemotherapy. According to INSIGHT statements, the BDUFA target action date for retofanilamab is July 25th, 2021. In addition to anal cancer, INSIGHT has stated it is pursuing development of retofanilamab as monotherapy and potentially registration-enabling studies in patients with MSI-high endometrial cancer, Merkel cell carcinoma, and lung cancer. In addition, they are evaluating the molecule in combination with other assets in their immuno-oncology portfolio. And finally, our second investigational ADC, IMGC0936, which targets ADAM9, is being advanced under a co-development agreement with Immunogen. Under our 50-50 collaboration, Immunogen is leading clinical development, and they have indicated they expect to complete dose escalation and move to expansion cohorts in the phase one study, with initial data anticipated by early 2022. We look forward to continuing to build momentum and advance our pipeline of innovative product candidates in 2021. We would be happy now to open the call for questions. Operator?
Thank you. As a reminder, to ask a question, you will have to press star 1 on your telephone. And to withdraw your question, please press the pound key. Please stand by while we compile the Q&A roster. Our first question will come from the line of Jonathan Chang from SVB Bank. You may begin.
Hi, guys. Thanks for taking my questions. First question, can you provide your latest thoughts and help set expectations as it pertains to the upcoming MGC 018 update at ASCO? You provided some color on the prostate expansion cohort. Maybe to follow up on that, should we expect to see any lung cancer expansion cohort data at ASCO?
Jonathan, thanks very much for your question. At this point, we're not expecting updates on the lung cohort given the very early nature of that study. As I indicated previously, patients did not start enrolling in that study until after the beginning of this year. We haven't actually looked at the full data set available. We are devising the poster very shortly. But as of now, I don't expect the lung cancer patients to be included in the update.
Got it. Thank you. And one clarifying question. I think I heard this, but I just want to double check. Are both the MGC018 expansion cohorts in head and neck cancer and melanoma evaluating the same 3 mg per kg dose level and regimen as the other ongoing expansion cohorts?
That's correct. The new expansion cohorts in head and neck and melanoma are at 3 mg per kg. Q3 weekly.
Got it. And just one final question from me. What are your latest thoughts on potential 018 updates beyond ASCO this year?
So we intend to provide updates at future scientific meetings this year. We are considering a submission to ESMO. Obviously, the date has not come up yet, but that is in the planning stage.
Got it. Thanks for taking the questions.
Our next question will come from the line of Peter Lawson from Barclays. You may begin.
Hey, thanks for taking my questions. Just as we think about the ASCO data for B7H3, I guess two parts, really. Kind of how much prostate data should we expect to see? And would we see any other indications, what triple negative breast cancer or any of the other earlier data?
Thanks, Peter. So with regard to the quantity, as I said, we're doing a cutoff this past week in terms of the data update. I haven't seen the actual data as yet as we devised the poster. My expectation is you'll have in the new expansion cohort of prostate patients, there will be a double-digit number of patients included. As I said on the call today, we have treated over 20 patients. So given that we are looking at PSA results on a Q3 weekly basis and looking at scans on every nine-week basis, it is possible that we'll have a significant number of patients having at least some initial PSA evaluations in that prostate cohort. With regard to the triple negative breast, as I indicated, that is enrolling slower than the prostate and lung cancer patients, and don't expect to complete enrollment of the 20 patients in that cohort until the second half of this year. So we will not include that at the ASCO meeting. However, as we have indicated today, we have data from the 4 mcg per kg Q3 week dosing in the dose expansion. which, as I noted today on the call, will include three melanoma patients. We had historically said we had two prostate patients, and there will be another patient with another indication included in the study.
And the reason to add head and neck, was that influenced by Diage's trial or just the PDX model?
You know, as we commented today, the latter with regard to the PDX model was obviously very reassuring, but even before we had the PDX model data, as you recall, two and a half years ago, we presented very compelling data of enoblituzumab combined with PEMBRO and late-line head and neck patients with 33% overall response rate with a lot of durability of those responses. As you know, frontline head and neck cancer treatment is pembrolizumab plus chemotherapy. So the ability now of potentially treating a frontline population with two different checkpoints based on PD-L1 status plus anoblutuzumab was very encouraging to us, and we thought it was very natural then to add an MGC018 in late-line patients as well.
Okay. Just a final question. Would we get durability data in the abstract, or do we have to wait for the presentations?
With regard to the abstract, again, as discussed today, the cutoff date was January. The abstract was due on February 17th, so very little data but for the comments on the four mcg per kg cohort group is included in that abstract. Having said that, as I have noted on earlier calls in the past month, I know there's at least one of the four MIG per kick patients that's still on therapy. So, again, we'll have to wait for the actual data to hear the update.
Thank you. Our next question will come from the line of Jonathan Miller from Evercore ISI. Your line is open.
Thanks for taking the questions, guys. I think let's start with maybe one more about the ASCO data. Are we expecting to see any color at all on those other cohorts in non-prostate cohorts mid-year, or should we have to wait for ESMO to see anything on the activity side from those cohorts? Secondly, you said you I thought I heard that you said PSA responses, you were happy with PSA responses in the MCRPC cohort. Is that, did I hear you correctly? Is it fair to say that those rates are holding in? And then maybe switching gears a little bit, let me hear those questions first before I inundate you. Thanks.
Yes, thanks, John. So with regard to the other cohorts and the timing, all I can project right now is obviously what we could do at ASCO. we typically like to present these data at scientific meetings and time it appropriately. So my sense is that it's most likely to be presented at one or more scientific meetings in the second half of the year. With regard to the PSA in the expansion cohorts, I'll just keep it general that the biological activity is trending favorably in the data that I looked at literally a week ago. And, you know, I won't say more than that. Obviously, we'll have some additional numbers come in this week. But, you know, from what I've seen so far, I'm very pleased what I'm seeing with regard to bioactivity, the safety profile we've described historically, and with the new patients, and then the additional data that we're getting from the formic-per-kick expansion cohort.
Thanks. I guess now we can switch gears maybe. I noticed the new CD123, CD3 moving forward there. How should we think about that in the context of the potential registrational cohort for flutacuzumab and your plans for updates on that data set?
Totally independent. The enrollment of the registration study of Flotatuzumab in the primary induction failure early relapse patient is continuing. We anticipate providing updates by the end of the year on that study. As I've highlighted before, we're very excited about the prospects of advancing our platform technologies So, with regard to this CD123 by CD3, this contains a slightly altered CD3 molecule that should dramatically reduce cytokine release but preserve the anti-tumor effects we have seen with Flotituzumab, plus the ability of having intermittent dosing of those patients based on the incorporation of an FC domain. So we're very excited as this is one of several molecules in our preclinical portfolio that's emerging on this advance in our platform technology.
Makes sense. And just one last one. On new expansion cohorts for MGD019, what's giving you confidence in prostate? I think melanoma makes sense for these sorts of targets, but prostate is a little bit different. Can you talk a little bit about what's driving you into that education?
So there are a couple of things that's driving. Obviously, with our strong interest in prostate cancer, we're looking at opportunities for to advance multiple molecules in that indication. As you probably remember, one of the patients that had an objective response, in fact a complete response, in our dose escalation study was a patient with castration-resistant prostate cancer, which again was quite remarkable. And that patient is still in remission And I think that's coming on close to two years now. I know it's at least a year and a half. So we're very pleased about that. Also, as you know, studies that were conducted with ipinivo in prostate cancer showed responses that were quite favorable, although they did not meet the objectives of the study for approval. The idea here of being able to use a safer and potentially safer and a very active molecule like MGTO-19 gives us a lot of enthusiasm. And then finally, as you know, one of our missions in our company is the combinability of our molecules. And so as we develop these molecules individually in a particular indication, we look for the opportunity to combine them in mechanisms that are orthogonal to each other to get to an even better response. Our preclinical data, for instance, combining MGCO18 and checkpoint molecules has been shown to be quite favorable. And so do not be surprised if future studies may be designed to ask those questions in indications that we are pursuing as monotherapy.
Next question will come from Steve and Willie from Stifel. You may begin.
Yeah, good afternoon. Thanks for taking the question. And I'm going to ask you a couple of 018 questions, if you don't mind. But I guess there seems to be a lot of emphasis around this notion of whether or not we're going to see, I guess, some resist-evaluable prostate cancer patients at ASCO, even though this is, I believe, the minority of most refractory prostate cancer patients. Is there anything that you can say just with respect to, I guess, the double-digit patients that may be included in the presentation? Of what proportion of those do you think we may actually be able to see some resist data in?
Thanks, Steve. So with regard to the expansion cohort, with regard to resist the valuable patients, I haven't looked over the latest list of patients with regard to whether they had measurable disease. What I've noted on previous looks, they seem to be following the normal composition of patients that have bony-only disease, which are a little bit more than 50%, and then patients that have either lymph node or or visceral disease that is measurable, which is a little less than 50%. So I'm assuming that we have a pretty normal distribution. I think that the issue becomes is whether we have any valuable scans at the time, because as I said, most of these patients came in in 2021, and we're only getting scans every nine weeks. if we don't have anything that's available by ASCO, we certainly will have it available in the second half of this year. So, you know, it's not that we're holding back anything. We just, you know, the patients have to have time to be evaluated.
Got it. That's very helpful. And I know in the literature, right, there's, the suggestion that the correlation between a PSA50 response and a resist response is pretty high. But do you think that correlation differs on a target-by-target basis in terms of just modality of therapy? Or do you think that that's just a correlation that broadly holds across the treatment landscape?
You know, I think the full answer is not in yet. I think that the recent data suggests a pretty good correlation. As you know, many of the agents that are approved for treatment are part of the AR inhibitor family, and so I suspect that the effects on PSA and then multiple prediction there may be different than, say, an ADC molecule with cytotoxic effects. I think we'll just need more time to evaluate this. I think that, you know, it is in the case here where you're using an ADC, the only thing that I can truly ascribe to the reduction PSA is actually a reduction in tumor. That's the only mechanism that I can see here, either by direct cytotoxic effects or possibly by secondary immunological mechanisms. So we'll have to see whether that correlation holds. I should also note that for patients that, particularly late stage patients that have continually rising PSAs, the ability to shut that off, that doubling time, should be also seen as quite favorable because ultimately we're not curing late stage patients. We're looking at both improving the morbidity and mortality of these patients and prolonging their lives. So I think, again, we're going to need more time to ultimately come out with the conclusions here. But as I said, you know, we were very excited last year by the initial data. We continue to see the current data in a positive light.
That's helpful. And just lastly, Scott, you mentioned the the possibility of combining ONA with PD-1 inhibitor. I know that the protocol for the MGC-ONA trial calls for, I guess, with or without retifanilamab. Have you started dose escalation with retifanilamab? And I guess, does some of the PD-1 plus chemo data that we've seen in the refractory setting kind of accelerate that trend? those development timelines, especially now that you've settled on a recommended phase 2 dose. Thanks.
Excellent question, Steve. So, you know, when we were starting the dose escalation, we expected to quickly go over and flip to the combo study with retofanilamab. However, we were obviously pleasantly surprised with the robustness of data we saw with the PSA reduction. And so rather than continue with that part of the protocol. As you know, we didn't even finish out the dose escalation. We went to the expansion. Now that we have so much more data with both tebotelemab, the PD-1 LAG-3, and with MGD-019, PD-1 CTLA-4, in addition to retifanilamab, we have a lot of different opportunities now and don't necessarily have to resort to just using retifanilamab. And so we're right now in discussions of next steps in designing those combination studies. And so I wouldn't necessarily assume that it's going to be retifamilamab.
Our next question will come from the line of Yagal Nakomovitz from Citigroup. You may begin.
Hi, Scott and Jim. Thank you for taking the question. Could you just clarify why you're combining inoblutuzumab with tibotilumab in the PD-L1 negative head and neck patients? given that tevotelumab targets PD-1?
Yeah, so, Yugal, this goes back to the observations we made and described last year at ASCO with regard to our FC engineering and the combination with tevotelumab. As you recall, we presented a very exciting data of margituximab with tevotelumab in patients that were HER2 positive in lay-line patients who the majority, or many of these, had very low checkpoint ligand expression. So very low PD-L1, very low LAG3. In fact, many of the patients were PD-L1-0. At the same time we were conducting the preclinical studies with that combination, we were also conducting inobutuzumab in combination studies with tevotelumab and demonstrated, as we have discussed before, the ability to drive up innate and specific immunity as a result of treating with the FC-engineered inobutuzumab, and by upregulating both LAG3 and PD-L1, we see that as an opportunity of now getting a much more dramatic therapeutic effect when added to tevotelomab. So, again, this is a phase one study in the enoblituzumab and PD-L1 negative, but our assumption is the same FC engineering that's in MARG, the way we studied positive clinical results, would translate the same way for the PD-L1 negative patients when given this FC engineering plus Tebow telemath. And as you know, the historical data from Merck with Pembro or from Bristol with Nebo in head and neck with PD-L1 negative was very poor. So any way to increase the expression here we think will have salutary effects.
Okay, got it. And then could you just comment on the rationale for expanding the Phase I MGC 018 study into melanoma? I'm just wondering if you also had mouse PDX data for melanoma as you did for head and neck.
Okay. So without revealing specific data, as you noted on our call today, we had at the 4 mc per kick three patients, with melanoma. That's all I'll say about those patients and wait until the ASCO presentation. But I also should put this in the context of our historical experience in melanoma. With an Oblituzumab as a single agent, we had objective responses or tumor reduction in late-stage melanoma patients. And the same thing was also observed in patients who were treated with our bispecific MGD-009, which was the CD3 by B7H3. So we have many avenues at this point that suggest melanoma would be a good population to continue to evaluate. And of course, we also have done immunohistochemistry studies with tissue specimens from melanoma patients showing high expression of B7H3. Great.
Thank you very much, Scott.
Our next question will come from Brad Canino from Credit Suisse. You may begin.
Great. Thank you for having me on the call. I'll just ask one and not about data expectations, but I do have a question on the product market fit for the gastric cancer module A that you're going to be reporting at ESMO, because I understand the rationale of a chemo-free regimen to reduce toxicity. But, you know, these patients present with pretty debilitating symptoms from the tumor, are likely struggling to eat, and I would think they would want a fast response, which is what the chemo would provide. So how important is the chemo-free regimen? Is this just a niche opportunity relative to your chemo triple that you'll have later, or do you think there's really a demand here? Thank you.
That's an excellent question, Brad. Nice to meet you via phone. So, again, if you recall, we had conducted studies in second line of margituximab and pembrolizumab, and actually saw, and these are patients who have progressed on Herceptin and chemotherapy, and saw in the HER2-3 plus positive, PD-L1 positive population, actually a very quick response in certainly a large number of those patients. And the additional value of that is that our overall survival of that population was dramatically better than the approved second-line therapy, ramicirumab plus paclitaxel, and much better than first-line therapy when you compared across different studies. And so that was the rationale. Also, the fact is that when you look at the patients in the frontline setting, Their HER2 expression tends to be higher, and their PD-L1 expression tends to be higher. So, again, we are expecting or had expected and hope to be able to present the data later this year at the scientific conference addressing the question you had in terms of the rapidity of response and the durability of that response.
Great. Thank you. Look forward to ASMO.
Our next question will come from the line of Boris Peeker from Calend. You may begin. Boris, your line is open. And our next question will come from the line of Absar Darrell from Guggenheim Securities. You may begin.
Great. Thanks for taking the question. The first one, I guess, is another sort of clarifying question from the introductory remarks. Just wanted to confirm that all but two patients in the sort of the prostate expansion arm remained on therapy and then also on the pace of enrollment and melanoma and head and neck. And then I have a second question.
So as the data that I had seen as of a couple of days ago, that is correct. So I can't tell you if anything changed today, but as of a couple of days ago, that statement is correct. With regard to the speed in which we will enroll the head and neck and melanoma patients as cohort, this is just opening up. The expectation is that we would enroll a significant number in the second half of this year. But, again, we'll provide updates over the course of the year how that's going.
Great. Thank you. And then one question on MGD-024. I guess based on the preclinical evaluation you've done so far, how are you thinking about sort of maybe frequency of administration as it kind of relates to sort of flutatizumab, you know, once every week, once every two weeks, etc.? ? Any thoughts around what that interval could be based on what you're seeing?
Good question. Obviously, we'll have to see what happens in patients, but I think a Q2 weekly dosing regimen is certainly possible. It may reduce to Q1 or increase to Q3. We'll just have to see. Great. Thank you.
Once again, as a reminder, that's star 1 for questions, star 1. Our next question will come from David Lebowitz from Maury Stanley. You may begin.
Thank you very much for taking my question. On the gastrointestinal trial, Module A, how many patients were originally expected to be presented at ASCO versus the 40 that will be presented later this year? And what, I guess, does it... What is the driving factor behind the, I guess, the leading physician wanting to postpone presenting the data at this point? What factors are, I guess, pushing wanting to just hold off until the complete data set is ready?
Yeah, thanks, David. It was very simple. As you know, our decision to move forward is based on a central review of 40 patients, and we only had about 20, a little over 20 patients that had investigator review, so it was really an in-between presentation. And so, since there was no compelling decision and we're waiting until the full 40 patients, get evaluated radiographically, we didn't see any harm on allowing the investigator to present this at, hopefully, at ESMO. You know, given that it was only a partial study, this was going to be a poster session, and with a much more fuller data set, there is obviously a potential for an oral presentation with this type of study.
Have any of the patients in that original abstract undergone the, I guess, radiographic assessment to this point?
So they have all the patients, 20-some of our patients, have investigator evaluations. There's been some additional patients, but there's no full central review data set available at this point.
Okay. Thanks for taking my question.
Thank you. And I'm not showing any further questions in the queue. I'd like to turn the call back over to the speakers for any closing remarks.
Thank you, Operator, and thank you for your participation in the meeting today. We look forward to updating you on our programs in the not-too-distant future. Have a wonderful afternoon.
This concludes today's conference call. Thank you for participating.