Greetings and welcome to the Y-mAbs Therapeutics Inc. Second Quarter 2019 Earnings Conference Call. At this time, all participants are in listen-only mode. [Operator Instructions] As a reminder, this conference is being recorded. It is now my pleasure to introduce your host, Mr. Thomas Gad, Chairman and President of Y-mAbs. Thank you, Mr.

Gad, you may begin..

Thank you Terry. Hello everyone and thank you for dialing into our second quarter earnings call. Today we'll here remarks from our Chief Executive Officer, Dr. Claus Moller, and our Chief Financial Officer, Bo Kruse. Overall, we are very pleased with our second quarter results.

Our reported spending of $27.5 million year-to-date is really a direct result of a highly dedicated and productive team effort to prepare Y-mAbs to be ready to submit two BLAs in 2019. We ended the quarter with $120 million in cash and taking into consideration our potential approval timelines of Q3 2020 for naxitamab and omburtamab.

And also taking into consideration that each product have rare pediatric disease designation from the FDA which should entitle both product to a priority review voucher, we are very pleased with our financial position.

As a company, Y-mAbs continue to work very hard to solidify our position as a leader in pediatric oncology focusing on rare pediatric cancers with clear unmet medical needs. And with that I am very pleased to give the word to Dr. Moller. Thank you..

Thank you very much Thomas. And welcome to Y-mAbs second quarter conference call. This is our first ever earnings call after our IPO in September last year and we are pleased that you have chosen to join us.

Since our IPO we have worked hard to make sure that our lead product candidates naxitamab and omburtamab continue to advance through the clinic towards the BLA submission as Thomas just mentioned.

We are planning to initiate this informs of rolling BLAs before the year-end for both assets and as you previously heard November is the target timeline for naxitamab and the following months is most likely going to be the omburtamab start. We started Y-mAbs in April, 2015.

And since then we believe that we have demonstrated a strong track record of execution and improve the ability to innovate, compete and grow. Since our IPO we have increased our head count with about 65% to a total of 48 people by the end of the quarter.

And we feel that we are well positioned to move naxitamab and omburtamab to approval and commercialization next year and to capitalize on the growth opportunities presented by our earlier stage pipeline. We advanced our bispecific GD2CD3 antibody in the clinic earlier this year and expect the IND filing on Omburtamab-DTPA to be filed later this year.

That's the antibody we are planning to radiolabeled Lutetium-177. We have recruited all the patients in the Study 201 that we need for our BLA planning for the treatment of relapsed/refractory high-risk neuroblastoma and we also had the promising pre-BLA meeting with the U.S. FDA.

At the meeting we reached alignment with the FDA on an Accelerated Approval Pathway for naxitamab along with a rolling BLA submission. The Company expects to submit the clinical and safety portion and the non-clinical portion of the BLA in November 2019.

For the CMC portion, the Company believes it will have sufficient data from the PPQ batches to complete the CMC portion in early 2020 most likely in February.

Under naxitamab’s breakthrough therapy designation, the compound qualifies for a rolling BLA, which enables individual modules of the application to be submitted by the Company and reviewed by the FDA on a rolling basis, rather than waiting for all sections to be completed before submission.

The rolling application process will provide the Company with the opportunity for ongoing discussions with the agency and during this rolling process, the Company anticipates that it will be able to address what ever matter may be raised by the agency during the evaluation of the filing.

At this year's ASCO Conference in June, naxitamab data from 24 patients with primary refractory neuroblastoma enrolled in this Study 12-230 was also presented. These 24 patients had bone marrow disease and all of them managed to get a complete response on a naked antibody alone.

In addition, 22 of the patients also had neuroblastoma in their bone and as shown by MIBG scans. The MIBG scans after treatment showed other parts of the complete remission in 19 of 21 patients corresponding to 90%. So we are still seeing very nice dramatic responses in these patients.

12 patients maintain progression-free survival from two months to 56 months after enrollment with the median progression-free survival of 29 months more than two years. As a reminder naxitamab is still an outpatient treatment.

In addition, recruitment of the Phase 2 Frontline Study in high-risk neuroblastoma patients continues as progressed and progress has anticipated at MSK. The naxitamab Phase 2 study for patients that do not respond to chemotherapy and do not respond to naxitamab, which is basically double-refractory patients. It is also ongoing.

We call the protocol HITS, it's the combination of the humanized antibody irinotecan, temozolomide and sargramostim, the GM-CSF. At ASCO, we presented data from 46 heavily pre-treated patients with a median age of 6.6 years, and the median to prior relapses was presented.

At enrollment, seven patients had high-risk neuroblastoma refractory to induction chemotherapy, and while 39 had prior relapses. Early response assessed after two cycles was documented in 39% of the patients and were evenly split between complete responses and partial responses.

Later this year, we also expect to have interim data from the Phase 2 study in the naxitamab, while the treatment of osteosarcoma, the data is planned to be presented at SIOP in Lyon in France in October.

With the naxitamab, anti-GD2 antibody we believe, we might be well-positioned to develop treatments for a range of GD2 positive cancers, including both pediatric and adult indications.

In addition, as you probably have already seen, we have announced back in May, a development update on our cancer vaccine program with a vaccine against GD2 and GD3 proteins. The vaccine was originally developed also by Memorial Sloan Kettering.

To date more than 230 patients has been treated with the GD2, GD3 vaccine at MSK in New York under MSK sponsored IND. And the advances in Neuroblastoma Research Conference in San Francisco in May, 2018, we presented Phase 2 data for Stage 4 high-risk neuroblastoma patients.

In particular, a Phase 2 trial of 84 patients with vaccinated with the GD2-GD3 Vaccine, we saw that these patients actually had a 51% progression-free survival at two years and also a 90% overall survival at two years. And it's very well tolerated with no reported grade 3 or grade 4 toxicities.

Since we in-licensed the vaccine in June 2018, we have explored our options to establish commercial scale cGMP production of the vaccine, and we believe we now have a viable route forward for manufacturing and plan to begin using the newly manufactured cGMP product in the clinic at the end of this year.

Establishment of a clear path, a development path towards approval has been our prerequisite for advancing the GD2-GD3 Vaccine program and we are excited to move the program forward now.

We believe the GD2-GD3 vaccine for relapsed high-risk neuroblastoma may offer meaningful improvement in long-term treatment paradigm for pediatric patients and serving as a natural add-on to the naxitamab treatment of the patient. So first we put the patients into remission in naxitamab and then we vaccinate them to prevent them from relapsing.

Now turning onto omburtamab. Our second lead compound that is also planned to have BLA filing later this year. Omburtamab is a B7-H3 monoclonal antibody that is developed to use with radiolabeled Iodine-131. We are developing the compound initially for CNS leptomeningeal metastasis for neuroblastoma.

The next indication will be diffuse intrinsic pontine glioma, also known as DIPG and then also desmoplastic small round cell tumors known as DSRCT, all of which are highly B7-H3 positive tumors. We completed the enrollment the 18 patients with CNS leptomeningeal metastasis for neuroblastoma as needed for our filing of the BLA.

And we believe that we are on target to submit the first portion of the rolling BLA to the FDA under our breakthrough therapy designation before the year end. For DIPG, we recently shared positive interim data from the ongoing dose escalation Phase 1/2 study presented at ASCO.

A total of 37 kids were treated with 34 of them being evaluated for primary and secondary endpoints. The median age at enrollment is 6.8 years of age and there was no dose limiting toxicities in the study, among adverse events that were at least possibly related to the treatment.

There were no grade 4 or grade 5 events and only four reversible grade 3 events in four patients. The overall survival rate at 12 months was 64.7% of 22 of the 34 patients. And we are very excited about these data all derived from the first cohort of the DIPG study.

As a reminder, historical median survival from diagnosis in these patients are nine to 11 months with only 10% of the children surviving for two years following their diagnosis and less than 1% for five years. And we are looking at 15% median survival in the dose escalation study already.

In the field of bispecifics, our GD2-GD3 bispecific antibody enter clinical testing early this year in the Phase 1 study at MSK and the dose escalation part of this study is progressing as planned. We expect to have an update on this trial towards the end of the year or beginning of next year, depending on how the continued dose escalation is going.

We expect the next bispecific antibody we are working on to be our CD33, CD3 antibody and expect that to enter clinical development during 2020 for the potential users of CD33-positive hematological cancers.

We have received rare pediatric disease designation, one for each of naxitamab and omburtamab which entitle us to a priority review voucher upon FDA approval of our products. Assuming the drugs are approved before October 1, 2022 where the program currently is scheduled to expire.

The term of our MSK license provided, MSK is entitled to receive 40% of the income generated from the sales and therefore Y-mAbs 60%. And for the second, PRV, they will get 33% and Y-mAbs will get the remaining 66.6% from the sale of the PRV. So with this, I would now invite Bo to share his remarks on the second quarter financials.

Bo?.

Thank you, Claus. For the second quarter, we reported cash spending of $14.1 million, corresponding to focus of the increase in our spending compared to the first quarter of this year. This means that we ended the second quarter with a cash position of $120 million.

As our work on the BLA submissions for naxitamab and omburtamab progresses and the commercial ramp up for the potential launch of the two lead compounds accelerates, we’ve seen that annual increase and we expect amortizational increase in the second half of 2019.

R&D expenses increased by $6.2 million from $8.3 million for the three months ended June 30, 2018 to $14.5 million for the three months ended June 30, 2019. This was primarily due to a $2.9 million increase in manufacturing expenses for naxitamab and omburtamab.

In addition, expenses for outsourced research and supplies increased by $2.2 million for the three months ended June 30, 2019 due to our increased need for clinical trial support. The clinical expenses increased by $1.2 million for the three months ended June 30, 2019 due to an increased global clinical activity.

G&A expenses increased by $2.1 million from $2 million for the three months ended June 30, 2018 to $4.1 million for the three months ended June 30, 2019.

The increase in G&A expenses was primarily attributable to $1.4 million increase in employee-related costs, including salary, benefits and non-cash stock-based compensation for personnel related to our business activities. In addition, costs for setting up commercial infrastructure increased by $0.5 million for the three months ended June 30, 2019.

The increase in G&A expenses overall primarily relates to the infrastructure and administrative costs of being a public company. In total, the net loss increased by $7.7 million from $10.3 million for the three months ended June 30, 2018 to $18 million for the three months ended June 30, 2019.

For the six months ended June 30, the net loss increased by $16.2 million to $34 million compared to $17.8 million for the corresponding period in 2018.

The cash flows for the first half of 2019 show that the cash flow increased by $7.4 million from $20.3 million for the six months ended June 30, 2018 to $27.7 million for the six months ended June 30, 2019.

The increase in net cash used in operations was primarily due to an increase of $10.3 million in our net loss for the six months ended June 30, 2019 partly offset by stock-based compensation to employees, which increased by $0.7 million.

In terms of financial guidance as such the consistently since the IPO that the net proceeds would cover our operating activities and capital expenditures through the fourth quarter of 2020. This number does not take into account the potential proceeds from monetization of PRV.

As Claus mentioned, revenues from commercialization of naxitamab and omburtamab, all the proceeds from many potential partnerships that we may enter in the future. So we do believe Y-mAbs remain in a healthy financial position. Now this concludes my financial updates and I'll now turn the call over to Thomas..

All right. Thank you. Thank you everyone. I think this does takes care of our remarks and I'd like to open up the call for any questions. So if you can ask the operator to conduct the call from here. Thank you, Gary..

Thank you. We’ll now be conducting a question-and-answer session. [Operator Instructions] The first question is from Alec Stranahan, Bank of America. Please go ahead, sir..

Hey guys. Thanks for taking my questions. And congrats on your first earnings call as a public company. Just a couple from me..

Thank you..

Yes. And the first from me is regarding your GD2-GD3 bispecific. Could you give us a sense of what percentage of that we have accrued at this point? And I guess how do you see this asset fitting into the treatment paradigm if naxitamab gets approved and then I have another..

Okay. Well, I mean, we haven't disclosed any details on the recruitment but obviously, this is a dose escalation study, so we'd go from cohort-to-cohort and we have been true, I think at least the first three cohorts now. But we haven't disclosed, as I said, any details from this.

We have to wait between each cohort to see 30 days out, the last patient have any side effects before we can dose escalate. But we haven't seen anything that gives us any concern for now. We still probably need to get up another group of cohorts before we can expect to really start seeing serious effects.

Although, we should be close to what that level would be. So I think that basically takes care of that. We have said we would come with an update on the study towards the end of the year or early next year, depending on where we are in the dose escalation. Good news is that we don't – we haven't received any clinical hold yet, so it's still safe..

Great.

And sort of how do you see the asset fittings to the treatment paradigm alongside naxitamab approved?.

Well, I think we have something that works that's naxitamab.

If it turns out like five, six years from now, maybe even seven, eight years from now, that we get fantastic data in pivotal studies with the bispecific antibody in the neuroblastoma setting and osteosarcoma setting without any pain issues, which is the key challenge with GD2 antibodies, then this would naturally migrate into that setting also.

But remember that hundreds of thousands of patients that have GD2 positive tumors including all small cell lung cancer patients, a lot of melanoma patients, triple-negative breast cancer patients. So I think you should think more like the bispecific antibody in the context of the adult potential indications.

Right now the dose escalation study is basically for anybody with a GD2 positive cancer. We will continue exploring this of course in the pediatric indications, which is our primary mission as a company, but definitely also in the adult setting.

And my first shot would probably be to go for a small cell lung cancer when we have established the safe dose and probably also Ewing sarcoma, which is clearly an unmet medical need. That also seems to be expressing GD2s. So there's ample possibilities also outside the field that the pain is basically what's limiting the dosing of GD2 antibody.

And I think that the tolerability to the pain is less than the adults that we have seen previously than it is in the kids. So obviously a GD2 bispecific would really be potentially very attractive for a number of indications..

All right, great. Thank you. And then my second question is on your manufacturing agreement with SpectronRx, how long do you expect it'll take to get them online for the radiolabeling of omburtamab, particularly at the level of commercial production.

And I guess along those lines, how do you plan to split up manufacturing amongst your various CMOs?.

Well, I think first of all, Spectron will definitely be ready in the next three to six months to deliver. And initially they will just be delivering for clinical trial purposes. So we don't have any problems there. And I think the – what we initially will be doing is that for patients here in the U.S. will be using the two facilities here in the U.S.

that can actually do regulating for us. And the European one, we'll be ready for delivering for the European sites. But the good thing is that we can ship and we have also, right now, we are currently shipping from the U.S. to Europe because the European sites are not operational yet.

So we know that's possible and the product is usable within 72 hours of release from the lapping facility. So you have ample time to get it to the side and its working.

That answers your question?.

Yes, that’s perfect. Thanks..

The next question is from Boris Peaker, Cowen and Company. Please go ahead, sir..

Great. And I'd like to add my congratulations on having you guys hearing you for the first time in an earnings call..

Thanks Boris..

So first question is naxitamab, can you comment on the osteosarcoma data specifically, what should we be expecting and when?.

Well, I mean, I haven't seen any yet, so it's difficult for me to comment on – you see that whatever we have available in terms of PFS on the patients that have been treating what we have available in terms of tolerability, safety, et cetera. And I think most likely the patient cohort is going to be in the magnitude of about 30 patients or so.

We are not doing any analysis until we get a bit closer to the conference. So we have as much information available as possible. So honestly, I haven't seen the data yet except for I know the data part is fine..

No, but that's what I wanted to hear. So it sounds like just unclear, roughly 30 patients we'll see later this year..

Yes. Yes..

Okay. Okay, fantastic.

Maybe a similar – or actually maybe a similar question on DIPG and DSRCT, what should we be expecting and when?.

DIPG we presented some very nice update data at ASCO. I think the expectations you can have is that if this continues to look positive as it is right now, we will definitely go ahead and do an update again at ASCO 2020. Since this was the only study with a positive indication for anything in DIPG, everything else has not shown anything.

And if it continues to look like this we're definitely planning to give another update next year. The other thing relating to this is that there's clear interest in expanding the studies that we are trying to see if we can before next summer open additional sites or open a separate study on other sites for the DIPG patients.

For the desmoplastic small round cell tumors, we would expect to have a presentation later this year for an update on the desmoplastic small round cell tumor I think it's in November. We have an abstract approved for conference..

Okay.

And what conference would that be at?.

Bo, do you recall the name of the conference in Japan? I think did we send out the press release about it? I think we did..

Yes, CTOS..

CTOS, yes..

Great. Okay. I will take a look up to you guys. Maybe I have forgotten.

I guess and lastly on the priority vouchers, is there a way that potentially you can monetize them before actually receiving them?.

Yes..

And are you doing anything? Is that a direction you're considering?.

Well, anything is the possibility. We would definitely something we are looking at.

If we get a sufficiently attractive term say we find a pension fund that's tired of only getting minus 0.5% interest on the bonds and say, hey, maybe we can make 15% on – what do I know but we are definitely considering the possibility as a potential to have non-diluted cash into the company..

Great. Well, thank you very much for taking my question..

If we feel it's needed..

Okay. Thanks for taking my question..

Okay, thanks..

[Operator Instructions] We have a question from Robert Burns, H.C. Wainwright. Please go ahead, sir..

Hi, Claus. It's great hearing you on the first earnings call again..

Hi, Robert..

Three questions for me. So I guess the first one is, I just want to confirm from you that we're going to be seeing efficacy data at [SIOP] in osteosarcoma as abstract as it also don't seem to imply that there's going to be efficacy data in it? That’s my first one.

And then the second one is what sort of steps are you taking?.

But why don't I answer the first one first? We take the second one. So I don't forget the first and the second one. Give me the third question afterwards. We haven't said for sure there will be efficacy data but we're trying to see if we can get the PFS data for the patients.

And therefore there is nothing in the abstract because when the abstract was submitted there was no evaluation of PFS at that time point. So I haven't seen the presentation yet, at a distance it is not made yet, but we'll see if we can get data out of the – it's in the MSK database to data. So, it's not in the Y-mAbs database..

Yes. Okay. And so my second question is, I've noted that you said multiple times that you're trying to accelerate a [CMC] portion of the filing. What steps are you taking to try and accelerate that portion? How feasible is it here we might see an accelerated timetable for that portion. You said that you might be able to see but….

It's hard to accelerate something from November to two months. But we are doing what we can in terms of understanding what precisely is that the FDA wants in addition to what they already know about a repeat from the Q-filing. So we are doing what we can in terms of communicating with the agency.

But besides that we’re just following track and moving along. And I think at the end of the day, you also know that when we file the clinical part of the BLA, they're going to start evaluating that immediately. Then you're gong to split on it until they get the last part in February that's the whole idea to rolling BLA.

So typically for these compounds that are filed with rolling BLAs, instead of getting the typical six months from the PDUFA date approval, you typically see like one month to two months early approval of products that has been filed with rolling BLAs that are addressing unmet medical needs in oncology.

So I think in BLAs, we're not really looking at any significant little later date than we would otherwise get if we filed the CMC package one or two months earlier than February. But we are looking into trying to understand why it wouldn't be sufficient what we have..

Alright, it sounds good. And then my next question. Yes, so you're going to be submitting the clinical data portion in November. Can you just remind us what you anticipate the timeline to be with pivotal top line data release for naxitamab and omburtamab.

And a follow-up to that is can you sort of update us with the status of the Frontline active med program and patients with first line that you mentioned? And how does the pathway look like for adding HITS protocol to the maximum level of Naxitamab?.

How many questions was that? Could you start with the first one? What was the first question..

So just, can you remind us about the timeline for pivotal top line on naxitamab and omburtamab considering that you are….

So 24 patients from naxitamab that will go into the BLA filing. Of course, you'll have the data in November. We may have a suitable venue before ASCO, but we’ll find a suitable venue.

And depending on what we decided may even be that, that we can agree with the investigators to since this is a part of the study that since it's in the BLA, we can release the data before that. But we will have the data, we'll find a venue. For the omburtamab data, it's 18 patients with pharmacokinetic and dosimetry data.

So there is no efficacy in the 18 data from the 101 Study. So you hear after the pre-BLA meeting that, if the FDA is okay, in letting us file that we will have data that we have shared with the agency and that the pharmacokinetic and dosimetry data looks comparable at MSK and outside MSK and comparable to the data from the Study 03133.

And if that's the message, that's basically it. Then as you may recall, we are adding another 14 patients, on the top of the 18, so total of 32 patients.

And we have discussed with the agency that our post-marketing commitment after the accelerated approval next year, will be to provide the agency from these 32 patients with six months progression-free survival and two-year overall survival. Now that is discussion in topics.

So the agency can decide all the way up to they give us the approval, what our post-marketing commitment will be, but it's highly likely that is going to look like that. And those data of course, especially the progression-free survival data should be available probably by the midst of next year or on the second half of next year..

Okay. That sounds good.

And then with the HITS protocol, is there a pathway that will be added into the naxitamab label in secondary refractory patients?.

Yes. I think what we most likely will do is now, we'll get the first approval.

I'm not going to rock the boat and start talking about any additional indications or modifications, but then I will go ahead and ask for a Type B meeting with the agency and say, hey look, if we take patients in second line that our refractory to chemotherapy and then they get naxitamab and refractory to naxitamab and then we put them on this HITS regimen, and then we put 40% into remission.

And you see now say, we at that time point have 85 patients and you can see, if we do this, we get 45% or whatever it is into remission. Why don't you give us the indication for this in these patients, and why don't you say that it could be recommended to use this upfront.

I mean, why would you not use this before you give salvage chemotherapy, before you give naked antibody give the combination..

Yes. Now it makes complete sense..

And then you asked about the Frontline Study, and what we have said is that, we have about, at least 50 patients and more – or more in that study, now as a single center study, we are planning a multi-center study to start in the first half of 2020.

And again, when we have the approval for the second line, I would go and talk to the FDA about a potential approval in Frontline and find out what do they need from a multi-center study, what is the safety data needed. Are they satisfied with whatever efficacy data we can agree with them on.

And get a regulatory strategy in place after the approval, but not rock the boat right now and start talking about additional indication.

So, but we hope to be able to present data and again I do not decide what's being accepted for presentation at ASCO, but we would hopefully be able to present at ASCO next year data from our Frontline Study with the patients. Some of the patients will at that time point will have been at the Study for more than two-and-a-half year.

So hopefully we can present those safety data, hospitalization data and progression-free survival data, from the first cohort of patient. And so more than 50 patients most likely less than 100 patients..

Awesome. It sounds good. And I look forward to. Thank you so much, Claus..

Sure..

There are no further questions at this time. I'd like to turn the floor back over to management for closing remarks..

Thank you. Well, thank you everybody for joining us today. It's been a real pleasure to have our first quarterly earnings call, and I look forward to the next one. Have a good day everybody. Bye..

This concludes today's teleconference. You may disconnect your lines at this time. Thank you for your participation and have a good evening..