Good day and welcome to the Y-mAbs Therapeutics Incorporated First Quarter 2021 Earnings Conference Call. Today's conference is being recorded. Let me quickly remind you that the following discussion contains certain statements that are considered forward-looking statements as defined in the Private Security Liquidations Reform Act of 1995.

Because forward-looking statements involve risks and uncertainties, they are not guarantees of future performance and actual results may differ materially from those expressed or implied by these forward-looking statements due to a variety of factors, including the fiscal year ended December 31, 2021 as filed with the SEC on March 1, 2021 and in the Company's subsequently filed SEC reports.

At this time, I would like to turn the conference over to Thomas Gad, the Company's Founder, Chairman and President. Please go ahead, sir..

Thank you, Tonya. Good morning, everyone, and thank you for joining us today for our first quarter 2021. So during this quarter, we have continued our execution of our strategy and expanded on all three pillars of our business, which is first, our leading monoclonal antibodies DANYELZA and omburtamab.

Secondly, our bispecific compounds developed under the Y-BiClone tech platform. And finally, the SADA technology platform, which we also refer to as liquid radiation.

We've had a strong start to 2021 and we are thrilled to submit the Marketing Authorization Application for omburtamab for the treatment of pediatric patients with CNN -- CNS metastasis from high-risk neuroblastoma in Europe. We submitted that last week on April 27.

Further, we gave an update on omburtamab in the US and also our Type B meeting with the FDA on March 26 and here we are continuing to working hard towards being able to resubmit the BLA for omburtamab late in this second quarter or in the third quarter of this year.

We believe these are important achievements as omburtamab can potentially address a significant unmet medical needs and therefore, have a substantial impact on the treatment landscape for CNS metastasis where there is currently no standard therapy today.

As you know, we received US approval for DANYELZA in relapsed primary refractory high-risk neuroblastoma in November last year. We just started delivering DANYELZA in the beginning of February and saw demand from hospitals throughout the US. So this is very exciting.

The first quarter net sales of $5.4 million, represents less than two months of commercial sales and we are pleased to report these first revenue numbers.

Although we have not provided guidance on DANYELZA sales, I'm pleased to note that despite COVID-19 forcing us into a partial virtual launch mode, both revenues and reach exceeded our internal expectations for these first few months and we could not be more pleased with that. Going on the SADA technology continues to look very promising.

We had -- we recently had positive feedback from the FDA on our pre-IND package on our GD2 SADA construct and expect to file an IND in the fourth quarter of this year.

In addition at AACR in April, we reported that pre-targeted radio immunotherapy against GPA33 in a xenograft model of colon cancer demonstrated a high therapeutic index, a favorable tumor to tissue ratio showing radioactivity uptake of 122 measure 24 hours after injection.

GPA33 is expressed on 95% of all colorectal cancers and the IND for the GPA33-SADA is targeted for next year, so very exciting. The bispecific programs under the Y-BiClone platform continue to advance. Our IND for nivatrotamab was cleared last year and we are getting ready to dose the first patients in our small cell lung cancer study this quarter.

In addition, we are planning for Phase 2 expansion in neuroblastoma and osteosarcoma later this year. Our CD33-bispecific for pediatric AML is scheduled to enter into the clinic in late 2021 and will potentially be addressing an important pediatric unmet medical need as AML remains one of the most challenging hematological malignancies for children.

I'm pleased to note that SciClone Pharmaceuticals, our strategic partner for Mainland China and Hong Kong, received a clinical trial waiver for DANYELZA in March, which should accelerate our time to market and we continue to view this opportunity as significant for Y-mAbs potentially serving a large unmet medical needs in China.

We are very pleased with our progress so far in China. I can also note that Takeda filed a BLA in March of this year for naxitamab in Israel. So overall, we are very pleased with the continued interest in both DANYELZA and omburtamab globally.

We ended the first quarter with approximately $252 million in cash after having closed the sale of our DANYELZA Priority Review Voucher for $105 million. Under our agreement with MSK, we received 60% or $62 million of proceeds of that sale.

In addition, we completed an oversubscribed secondary offering led by JP Morgan, Morgan Stanley and Bank of America, in which we sold approximately $2.8 million shares of our common stock, including the full exercise of the over-allotment option at $41 a share, resulting in net proceeds of approximately $107 million.

So, we believe we have a strong balance sheet not only to support the continued conversation of DANYELZA and potential launch of omburtamab, but also to advance our Lutetium conjugated omburtamab-DTPA construct and nivatrotamab into late-stage development.

At the same time, we continue to advance our two platforms Y-BiClone platform and the SADA platform. We're very pleased with our current financial position and we'll talk more about that later in this call.

Taking our achievements into consideration, we believe Y-mAbs is very well positioned to expand on our commercial activities while at the same time advancing our clinical pipeline to continue to address unmet medical needs and we are very excited to continue to do so. And I'm pleased to hand over the call to Dr. Moller, our Chief Executive Officer.

Thank you..

Thank you, Thomas, and welcome to Y-mAbs Therapeutics' first quarter 2021 earnings call. We're very pleased that you have chosen to join us today. During the first quarter, we have worked hard to ensure that our pipeline advances towards the market.

Our efforts included initiating commercial sales of DANYELZA in the US, as Thomas just alluded to while at the same time we're making progress with the resubmission of the omburtamab BLA and submitting the European marketing authorization application omburtamab.

In addition, we have initiated a Phase 2 study with nivatrotamab in small cell lung cancer under our own IND and initiated two Phase 1-2 studies with lutetium-177 omburtamab DTPA in medulloblastoma and in B7-H3 positive CNS leptomeningeal metastasis tumors in adult patients, and advanced our ongoing studies in other areas.

We are also continuing to work on new bispecific constructs in our SADA programs. Now let me turn to naxitamab.

DANYELZA is indicated in combination with GM-CSF for the treatment of pediatric patients one year of age or older, and adult patients with relapsed or refractory high-risk neuroblastoma in the bone or bone marrow, who have demonstrated a partial response, minor response or stable disease to prior therapy.

This indication was approved by the FDA under accelerated approval regulations based on overall response rate and duration of response. We were thrilled to send out the first commercial miles to treatment centers including MSK across the country in early February.

The total net sales of $5.4 million as Thomas just mentioned, we are very pleased with the launch.

As you would expect, MSK is our largest customer to date, but whilst have been shipped to more than 10 other cancer centers across the country now and our highly targeted commercial and medical affairs organization has done an outstanding job in educating physicians and nurses about DANYELZA.

Many treatment centers have had their first experience with DANYELZA and we believe the treatments have gone generally very well. In addition, we have had pre-BLA meetings in China and together we SciClone, we expect to submit the Chinese BLA in third quarter of this year, which hopefully will lead to a 2022 approval and launch in China.

Our clinical trials ongoing with DANYELZA in Barcelona, Spain and at MSK in New York for our first line neuroblastoma maintenance treatment as well as chemotherapy combination with naxitamab for refractory neuroblastoma patients are also progressing nicely.

We are working to initiate an international Phase 2 multicenter trials for DANYELZA and both frontline and with chemo combination treatments and we also have a Phase 2 osteosarcoma multicenter trial ongoing. Now turning to omburtamab.

On March 26, we had a Type B meeting with the US FDA to discuss the road towards resubmission of the BLA of omburtamab for treatment of pediatric patients with CNS/leptomeningeal metastases from neuroblastoma.

We are maintaining a very close and open dialog with the FDA regarding the resubmission and have scheduled a second Type B meeting of June 1, where we hope to reach final agreement with the agency on the remaining details concerning this granularity of the data from our identified historical control groups and how we would work forward with this.

In order to agree on the statistical analysis plan, this additional granularity data was submitted to the FDA in late April. We still aim to resubmit the omburtamab BLA in the form of rolling BLA by the end of second quarter or in third quarter of 2021.

The European marketing application for omburtamab was prepared in parallel with the US BLA and was submitted to the European Medicines Agency, EMA last week on April 27 and the valuation of our application is scheduled for 210 days.

However, the revenue cluster up whenever we respond to any questions posed by the FDA, the European regulatory authority and the clock resumes only once we have submitted our responses, so the 210 basis without any responses from our side.

In addition, we have begun staffing for our European commercial organization this quarter and we are excited to prepare for our first European product launch.

As previously disclosed we are also developing omburtamab for Diffuse Intrinsic Pontine Glioma known as DIPG in a Phase 1 study at MSK and we are planning to open an multicenter Phase 2 study for DIPG patients later this year. For desmoplastic small round cell tumors known as DSRCT, we have a Phase 2 study ongoing at MSK.

Then turning to the lutetium labeled portion of our omburtamab B7-H3 antibody. In October 2020, the FDA cleared our IND firm the 177 lutetium omburtamab-DTPA for the treatment of medulloblastoma, which is the most common type of primary brain cancer in children.

Medulloblastoma are invasive rapidly growing tumors that unlike most brain tumors spread through the cerebrospinal fluid and frequently metastasize to different locations along the surface of the brain and the spinal cord.

Our international multicenter Phase 1/2 trial is open for pediatric patients with medulloblastoma and based on our clinical experience from treating 27 patients with medulloblastoma with our Iodine-131 omburtamab construct.

We are very enthusiastic about this new trial and to see this construct moving into the clinic and to get started on establishing safety profiles to determine the maximum tolerated doses in this mode of using the omburtamab antibody.

In this study known as 301, we hope to leverage our prior clinical experience from the Iodine-131 omburtamab once giving -- once again giving the infusion through Ommaya Catheter and Reservoir.

In addition, our basket trial in B7-H3 positive CNS/leptomeningeal cancers in adults known as Study 302 where we hope to leverage our prior experience from treating more than 25 adults with the iodinated version of omburtamab is now open for the first adult patients to be screened and treated with 177 lutetium omburtamab-DTPA and we are thrilled to widen our clinical reach to include adult indications.

On our bispecifics, we are also excited to widen the nivatrotamab's clinical reach to include adult cancer patients in our Phase 2 study with subcutaneous administration of the bispecific. We also plan to expand the ongoing nivatrotamab at MSK into separate Phase 2 arms, one in neuroblastoma and one in osteosarcoma.

In addition, we are preparing an IND for the treat -- for the next in line bispecific antibody the CD33 bispecific generated on our Y-BiClone platform and the IND for pediatric AML is scheduled for second quarter of this year which is the Q1 quarter. Now turning to our SADA technology.

As you know we are very excited about the prospects for this technology and we are making good progress on preparing our fourth slow SADA targets for clinical development. At the AACR Annual Meeting in April, we presented our first annual data for the GPA33-SADA. In a xenograft model of colorectal peritoneal carcinomatosis.

GPA33-SADA showed a favorable tumor to blood ratios radioactivity uptake of 122 measured 24 hours after injection. GPA33 is expressed on 95% of all colorectal cancers and we are targeting an IND for the GPA33 next year.

Our other publicly announced targets includes GD2-SADA for potential use in GD2 positive solid tumors for which we expect to submit our first IND in the first quarter of 2021. We also have a B7-H3-SADA for the intended use in treatment of prostate cancer and we have HER2-SADA for potential use in breast cancer.

We believe the SADA technology can potentially improve the efficacy of radiolabeled therapies in tumors that have not historically demonstrated meaningful responses to radiolabeled agents and we are truly excited about our SADA technology on liquid radiation technology.

With the launch of DANYELZA, already leading to deliveries to multiple treatment centers across the country and internationally and the planned resubmission of the omburtamab BLA coming up, we believe that we are well-positioned to continue the development of Y-mAbs as a commercial-stage Company.

Concurrently, we plan to widen and deepen our pipeline by advancing our antibody constructs through the clinic predominantly the SADA constructs the bispecific and the next generation omburtamab DTPA radiolabeled antibodies.

In other words, we remain busy and we are very excited to move forward and build a business that helps patients and elevates our continued development. Now, let me invite Bo to share his remarks on his -- this quarter's financials. .

Okay. Thank you, Claus. We reported net income for the quarter ended March 31st, 2021 of $33.4 million corresponding to $0.80 per basic share was $0.75 on a fully diluted basis. This compares to a net loss of $26.2 million or $0.26 per share basic and loses for the quarter ended March 31st, 2020.

The main reasons for the net income to go up is revenues and other income. We reported net revenues of $5.4 million for the quarter ended March 31st, 2021 representing the sales of DANYELZA and there were no revenues reported in the quarter ended March 31st, 2020.

We also recognized $62 million from monetization of the 10 years of PRV as other income in the quarter ended March 31st, 2021, whereas there was no other income in the quarter ended March 31st, 2020.

As we take a closer look at the operating expenses for the first quarter of this year, we note that R&D expenses have increased by $3 million from $18.6 million for the quarter ended March 31st, 2020 to $21.6 million for the quarter ended March 31st, 2021.

This increase was primarily attributable to a $2 million increase in outsourced manufacturing expenses, $2.5 million increase in employee-related costs, and $0.8 million increase in the clinical trials in the first quarter of this year. The increases were partially offset by a $3.1 million decrease in outsourced research and supplies.

Selling, general, and administrative expenses increased by $3.9 million from $8.1 million in the quarter ended March 31st, 2020 to $12 million for the quarter ended March 31st, 2021.

The increase in selling, general, and administrative expenses primarily reflects a $3.3 million increase in employee-related costs including salary, benefits, and non-cash stock-based compensation for personnel. We ended the first quarter with a cash position of $252.3 million compared with 2020 year-end cash position of $140.6 million.

The increase was driven partly by the completion of the sale of our DANYELZA PRV in January and partly it would fetch the $107.77 million net rates in conjunction with our secondary offering in February. Cash used in operating activities show that the cash burn increased by $10.1 million to $31.9 million for the quarter ended March 31st, 2021.

The increase was primarily caused by the increase in operating expenses for the period as our work on the omburtamab BLA resubmission has progressed. We have continued to accelerate the launch activities of DANYELZA and omburtamab if approved which has also caused our operating cash burn to increase.

We expect the cash burn from operating activities for 2021 to remain roughly in line with the rate of the first quarter of 2021. We continue to believe that Y-mAbs remain in the healthy financial position. This concludes the financial update and I'll now turn the call over to Thomas. .

Thank you, Bo and thank you Claus. Tonya I think we can open up the lines for Q&A at this point. Thank you..

Thank you. At this time, we will conduct a question-and-answer session. [Operator Instructions] Our first question comes from David Lebowitz from Morgan Stanley. Please proceed..

Thank you very much for taking my question. Congrats on the nice launch. My question is on the launch itself.

Are there any specific dynamics regarding the initial uptake aside obviously from Memorial Sloan Kettering being the largest customer? Is there any stocking that some hospitals might do to prepare and will there be a lumpiness that we might see as the year goes on just given the nature of the small population any insight you might provide there would be helpful?.

Yes, absolutely. Thank you, David. I think of course, there were a number of patients that was converted from special license use or compassionate use when the product became commercially available that was converted at MSK but I don't think you'll see any stocking of this.

So, it's -- that's just reflecting you can see maybe a quicker ramp up than you could have expected. But I definitely don't foresee that from then ordering that we have seen that sites are stocking up anything typically beside will be using two vials per infusion per patient and typically doing four cycle three intrusion Monday, Wednesday, Friday.

So, if they are planning to treat that patient next week, they would have ordered the product by yesterday this week, six vials for the next week. And then so we get and we can see that - that's the pattern we see from both at MSK and also sites outside of MSK. They order for the patients that they are planning to treat the following week.

And because we can ship basically on a day-to-day and it's a relatively expensive product.

So, I don't think there's any stocking issue and I think as is it -- we are very comfortable with the initial launch we are in particular very pleased to see that a number of sites as you said more than 10 sites outside MSK have started using DANYELZA and I think some of them have treated actually quite a bit of patients now so and continuing to put new patients on treatment.

So, very good start for us. Very happy with the sales teams effort..

That's helpful.

As far as the special license use being converted is that mostly done at this point or should we expect more of those patients to convert as the year progresses?.

No, that happened in February. So, that's done. So, nobody -- that no more patients had already existed. And I think the last clinical trial patients. So, there was still a few study patients that needed to go into to our clinical trials but that's also happened in the first quarter.

So, we don't have any additional clinical trial recruitments ongoing in the US for naxitamab. Well, I think we are no more early access patients and no more clinical trials.

Thank you very much for taking my questions and again, congrats on the first quarter launch..

Thank you very much David..

Our next question comes from Alec Stranahan with Bank of America. Please proceed..

Hey guys. Thanks for taking my question and I want to offer my congrats on the launch so far as well. Two from me. So, the first United Therapeutics posted better than expected sales for Unituxin in 1Q and they pointed to the fact that kids are starting to come back for treatment as the pandemic abates.

So, I'd be interested to hear whether you're seeing similar market dynamics for DANYELZA and then any feedback you're receiving on clinical experience and treatment sites outside of MSK that are maybe using DANYELZA for the first time would be great. Thanks..

Thanks, Alec and I think it's difficult for us to say anything about whether the patients are coming back from COVID-19. I would say the number of patients we see on the side we know the best which is of course MSK is pretty stable was stable last year and doesn't seem to have changed a lot.

I think what the increased sales number for United Therapeutics to the best of my knowledge is two things.

It's plus 13% price increased by January 1, which always helps a bit, and but it's also the fact that United Therapeutics as you may also have seen in their report decided to abandon their attempt to get a supplementary BLA for the relapsed-refractory setting where we have an approval and I think that made them stopped sponsoring clinical trials in the relapse-refractory setting and therefore, those trials are continuing on the COT auspicious and they probably now have to buy the product, so I think it's a combination of those things, but it's great to see that the market has that size because it's reinforcing us and that we have a fantastic opportunity for these patients in the relapsed-refractory setting that is offering a treatment that doesn't necessitate hospitalization for eight days in the context of administering this product and that it's not a 10-20 hour infusion, but just median time to infusion it's about 37 minutes for naxitamab, while we are still giving 2.5 times as much antibody.

So, I think we are very satisfied with the situation, but of course also with the fact that United Therapeutics things gave up getting the approval for supplementary BLA and refractory setting..

Did that answer your question up?.

Yeah, the feedback on the -- on maybe sites that are using DANYELZA for the first time just their clinical experience..

Yeah, I think we have been positively surprised, but I also know that our research nurses and MSLs are doing a great job and making sure that the centers are comfortable.

I mean, I'm not saying that nobody is seeing any side effects or having any infusion issues, you always have that in particular with the product like a GD2 antibody, but it's gone very well and as I also mentioned we have sites that have treated more than four patients already.

So that's been very encouraging, so most of the experience has been very positive..

Okay. Great. Thanks. And congrats again on the progress. .

Thank you, very much Alec..

Our next question comes from Etzer Darout with Guggenheim. Please proceed..

Great. Thanks for taking the questions and offering up congrats as well on sort of the early launch for DANYELZA. I guess, the first question is, are you seeing enough maybe data week to week to gauge sort of demand beyond MSK at this point. I know it's early and I guess as we think about sort of the second quarter and beyond.

And then I have a second question. .

Well, I mean I think its way too early for us to start guiding on anything. We are satisfied with what we saw in the first quarter. If you were broadening it to say would I expect that we would be able to beat first quarter sales in the second quarter. I certainly hope so, but I think it would be at a very early stage now.

So but that's also kind of like responding to the issue about the stocking. I don't think what we saw with the $5.4 million net sales in first quarter was a reflection of somebody stocking the products.

So, I would definitely expect us to be able to exceed that sales number for the second quarter, but right now to start predicting anything I think it's too early..

Great and I think then getting questions around sort of going back to sort of the bystander effect with antibody drug conjugates and we talked about this earlier on.

Just wondered, if you could maybe sort of compare and contrast if you will on what sort of the radio nucleotide and its ability in terms of sort of the bystander just given sort of the interest that we see sort of coming in from investors to this point..

Yes I mean, there is no doubt that the interest in radio conjugated antibody construct is increasing also from big pharma. I think everybody is paying attention to roasted recently presented new data with the three step technology for basically a similar type of technology.

The only thing that to our start-up they are just using full antibodies and a clearing agent and then instead of using a beta-emitter they're using an alpha emitter, but with our technology we can also use alpha emitters. I'm a strong believer in alpha mirrors.

We just not at the point where we have construct I'm ready to push formerly into preclinical development, but we believe that our Proteus technology for using alpha emitter with our SADA tech will be ready within the next 12 to 18 months to initiate a formalized development. So we do see a lot of interest.

We also see a lot of interest from potential pharma partners to work with us on this technology. I think for everybody that looks carefully at the SADA tech it stands out compared to anything else that's out there in the radio conjugated field and that's also the feedback that we start getting from potential partnering.

Did that answer the question?.

Yes. Just maybe more specifics around sort of the bystander effect with really radio nucleotides compared to sort of what we see with ADCs..

Well, I mean the challenge with the regular nucleotides is that, if you don't get rid of them they keep circulating to your bone marrow and your bone marrow is the most sensitive organ.

You can also see something in the liver and the heart and the kidneys, but the bone marrow is typically what people -- is limited and of course also the blood and with the technology we are using because, we give the isotope cates in a DOTA molecule that is very tiny. It leaks out through the kidneys within hours after the administration.

And there is one thing that is the primary -- that's actually choosing that drives the radiation damage you get from two other tissues and that is the duration of the exposure and then of course also the intensity. But you can -- with those few hours of circulation of our isotope you can get to quite extensive amounts of radiation.

You may remember that Lutathera for neuroendocrine tumors is given us 200 mCi on a peptide that is having a relatively short circulation time, but 200 mCi is relatively high dose that's four times as much as we are giving for the omburtamab.

So I think we will see and I think that's also reflected with the data from the GPA33 that was presented at AACR with 122 fold as much radiation to the cancer cells as we got to the blood in those animals. I think that is what we can show that nobody else can show.

The only other data in this ballpark you can see is coming out from the three step procedures where you use a dextran like molecule to eliminate all circulating full antibodies. But for cancer patients to lose all your antibodies is probably not an optimal setting.

It works fine in an animal, but I would be cautious on exposing cancer patients for the risk of losing all their circulating antibodies including potential antitumor antibodies. But that's a completely different discussion. The time will show. .

Right. Great thank you and congrats again on the progress. .

Thank you very much..

Our next question comes from Joe Thome with Cowen. Please proceed..

Hello, good morning and thank you for taking my questions. Just a couple of the launch, if you could just walk us through a little bit the process of bringing new centers on board.

Is there a duration that's associated with that you have to work through any sort of kind of P&T committee approval in order to get DANYELZA onboard broadly? And then second from a reimbursement perspective have you seen any pushbacks from any centers outside of MSKCC and how much time will it take if there is any need to stabilize that? Thank you..

Sure. So we have a pretty clear set up for this and we also have a hub where we can help getting patient registered and help also getting reimbursement in place. Typically, what happens is that first of all, we haven't incurred any problems getting commission at sites to actually bring that product into the hospitals.

So that has been operating pretty smoothly. Almost everybody has been interested in getting practical assistance in terms of talking to research notice that know about the practicalities around the administration of the antibody and our MSL about the potential side effects etcetera.

So that has been quite smoothly -- reimbursement of course we were very interested and excited about how that would actually go on.

And I can say until now we have not had a single patients that was refused reimbursement and most I would say, more than 90% of the patients get the reimbursement in place within one to two weeks after the doctor suggest that they should have naxitamab.

We've only had one patient where it took four weeks and that was the only time, we have had that insurance company into the process and they gave in and that's accepted reimbursement that was no issues with that in the end. So that has been very nice and very successful. So, we were pleased with that.

There is no doubt in my mind that we are addressing an unmet medical need and they also have heard about the first cases of patients that were the parents have actually pointed through the possibility of rather than in this but that's refractory setting treating their kids with dinutuximab and chemo asked for naxitamab.

So but I think we are making good progress. .

That’s great and very helpful. Thank you very much..

Our next question comes from Robert Burns with HC Wainwright. Please proceed..

Hi, guys. Thanks for taking my questions and congrats on the launch as well as the quarter. Just one from me if I may.

So, I'm just curious as to how many of the Tier one prescribers, as you're commercialization team being able to make contact with to date and does the rate of contact track with your own internal expectations or has the pandemic affected it?.

Well, I can say that - I don't know what the rate in terms of Tier 1 customers that we have actually made contact with, but I would guess that we have made contact with about two-thirds at least of them and I can also see that among the sites that we have started shipping product to there is a couple of the really big Tier 1 hospitals that have started trying to use naxitamab.

.

Okay. That's completely fair. One additional follow-up. I'm sort of curious as well as it seems you may contact with two-thirds of the Tier 1 prescribers.

What is the average timing between contact and actual ordering of DANYELZA and have there been any gating factors on the prescriber and outside of the frequency that these patients are seeing at least that had limited DANYELZA?.

Rob I think it's way too early to that elaborating on that. Of course, we have a lot of statistics on this an output but it's only for two months and as I said actually as we are speaking now it's for three months. But I would say, I have not heard about any side Tier 1, Tier 2, Tier 3 that has said -- this is not relevant.

I mean sometimes this is up the attitude especially if they were principal investigators of the naxitamab or the omburtamab clinical trial not on the Unituxin clinical trials that they can do everything they need for these patients with Unituxin, but in reality it's not the truth.

I mean it gives all by itself that if you have a clinical study where only 42% of the patient come into remission.

You have 58% that your patients that has a been issue so there is -- but we are very early into the launch we are very happy with what we have seen and in particular very happy that we have been able to get actual commercial sales to more than 10 sites outside MSK so this early on in the launch process and we keep pushing out there and are seeing I would say continued strong interest in the product.

.

Now. I completely agree. Thank you the clarity, Bo..

Thank you. Have a good day..

Our next question comes from Peter Lawson with Barclays. Please proceed..

Hey thanks for the question.

And just as we think about the, the sales for the last quarter-on-quarter and then have trended and would say look like going into April?.

Well I think it's very early for us to give any indications. I think I've stretched myself as far as I can, when I said I certainly foresee that we would be able to outperform the sales of our first quarter and the second quarter.

So definitely, we have no indications that but what we saw in the first quarter is not reflecting real sales or use of the product. As I said we can see the sites are actually ordering when they have a patient they're getting ready to treat the patient in the next week they order before the end of the previous week.

So nobody is stocking up and they can you can -- if you look at our clinical trial data that has been published the median or the average number of doses or cycles the average cycle number per patient in this relapsed-refractory is 5.3 cycles of antibody.

And so that takes into consideration that patients -- some patients drop off after one cycle and some patients progress after three or four cycles and therefore drop off, but you end up with an average because we say we give five cycles after you come into remission and that typically happens after one two or three cycles.

And so, if you are in remission up the three cycles you end up with eight cycles. So the median is expected to be 5.3 based on our clinical trial data.

And that means that all the new patients that's started in February and in March and in April they will continue for an average of 5.3 cycles, which means that February patients will on average finish their treatment in July. And so, that means that we have a number of patients that come back right now for retreatment every month.

Did that answer the question?.

Yeah, that's really helpful.

Percentage of the sites do you think the treating more than one patient or had I guess, discontinuations or you've had decisions for citizens not to use this again just so kind of the products on that?.

Yes. I don't that you have any sites that have said, this was such a bad experience and never going to use naxitamab again, I don't think that has happened yet.

It may happen at some time all right, but it hasn't happened yet but -- and I think that's definitely a number of sites that have as I said reported positively back and started treating not only one patients but several patients. But as I said, we are very early into the launch, we are talking very preliminary data.

I certainly hope when we have the second quarter call that we will be able to give you a bit more details.

But I think typically you want to have at least three or four quarters before you start feeling more comfortable about treatment and retreatment and how many patients actually completed all the cycles they were incented and to see whether the 5.3 average number of cycles that we saw in the clinical trials is also reflected on what's happening in the clinic.

So I think we are very early on and I hope that gives you some clarification, Peter. .

Yes, that's great.

If you had any sites converted from United Therapeutics [Indiscernible] towards our stated?.

Well, it's two different indications. I don't think any of the sites outside MSK that are using Unituxin, but stop using Unituxin because it's approved in patients that are in complete remission in front-line. So many of them will probably continue with that for a while until the parents say, hey, come on, I don't want my kid in the hospital.

I want my kids to be treated with the new outpatient treatment.

But more data need to be reported and hopefully we get some time point can get the supplementary BLA for the front-line indication, but I think we are as is it very early on now and so we are approved in an indication where nothing else is approved our United Therapeutics just told us that in the quarterly report that they are not pursuing a supplementary BLA for those patients.

.

Okay. Thank you so much. Congrats. .

Thank you..

[Operator Instructions]. Our next question comes from Tessa Romero, JPMorgan. Please proceed..

Good morning, guys. Thanks for taking our questions. And congrats on the initial progress here. Switching gears to a pipeline question from me, a question actually on the upcoming ASCO presentation. I think you will be giving an update on the Phase 1 DIPG study.

How should we be thinking about our win scenario for this update? And then can you remind us, what are the next steps in the DIPG and DSRCT indication? Thank you so much..

Yes. So the DIPG is an update presentation from what was presented two years ago in 2019 by Mark Souweidane. So you will see data from a higher dose cohorts and you will see data on more patients and you'll see additional follow-up on the survival.

As you may recall that, the survival in these patients is typically less than 10% after two years and very, very rarely you see patients surviving five years. So that's what you could expect.

And in terms of continued planning for the DIPG, it's our intention to initiate later this year a multi-center Phase 2 study that potentially could support a supplementary BLA for omburtamab iodine in the indication DIPG.

So but first, we need to get the approval for omburtamab in the CNS leptomeningeal neuroblastoma indication and then with the data from that Phase 2 study hopefully we can get a supplementary BLA or as a minimum together with the Phase 1 study from MSK generate enough data to support reimbursement compendia listing for omburtamab iodine in the DIP setting.

On the DSRCT, as you may also recall that's a very tiny little indication it's maybe a 150 young adults and teenagers every year in the US that diagnosed with this horrible sarcoma into peer to nearly and there we give the omburtamab iodine as an IP administration in 215 ml of saline solution to these patients and the first study the Phase 1 study where data was presented at CTOS in 2019.

We have shown the safety and clear indication of treatment benefit in the Phase 1 study where patients only were given one dose and now we have expanded into a Phase 2 study where patients received two dose. Again, as I said, I think the regulatory path for these patients is still a little uncertain in the current setting.

As I said, it's an ultra-orphan indication would it be sufficient to have data published just to see any uptick in that you'll have to wait and see until the product comes to the market and more data is generated and what the FDA added to it would be to this, but it's definitely the data that's been generated in that setting also. .

Okay. Great. Thanks a lot. And then one clarifying question hopefully it's quick.

It's just -- have you guided to a number of sites for DANYELZA by the end of this year and just wondering is that you know we got in turn?.

We haven't given any guidance at all. I think what we have said is that I think Bo remind me the media and analyst expectation for sales is for DANYELZA this year, what is that is that 20 or 30. .

It's in the mid 20. .

That's in the mid '20s and the only thing. .

Claus, not sales just site. So site….

Yes. And that's -- but that was my point, we haven't said anything about sites. We have said that we are very comfortable with the median sales estimation by the analysts and feel comfortable that we can definitely reach and most likely also exceed that median.

But we are still very cautious in what we are -- we need to learn more about what's happening out there and also to see how well this -- in this. And as I said until now, we have been very positively surprised that how well this industry is managing the administration of naxitamab.

So they are definitely doing a good job, but we are early on in this process, but very positively surprised about how things have been going. I hope that with a little helpful, not too helpful. .

No. That's thing, I just wanted to clarify. Thank you so much..

Yeah. Thank you, Tessa..

At this time, I would like to turn the call back over to management for closing comments. .

All right. Well, thank you everyone for joining us today and we look forward to continuing working at perhaps and expanding our pipeline and launches. .

Well, thank you. Have a great weekend. Thank you..

Thank you. This does conclude today's teleconference. You may disconnect your lines at this time and thank you for your participation and have a great day..

Thank you..