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ArQule (ARQL)
Q3 2018 Earnings Conference Call
Oct. 31, 2018 9:00 a.m. ET

Contents:

  • Prepared Remarks
  • Questions and Answers
  • Call Participants

Prepared Remarks:

Operator

Good day, ladies and gentlemen, and welcome to the Q3 2018 ArQule, Incorporated earnings conference call. [Operator instructions] As a reminder, today's conference may be recorded. I would now like to turn the call over to Marc Schegerin, senior vice president of strategy, finance, and communications. Sir, you may begin.

Marc Schegerin -- Senior Vice President of Strategy, Finance, and Communications

Thank you very much, Mark. Good morning, everyone. Welcome to the ArQule investor conference call reviewing operational and financial results for the third quarter of 2018. I'm Marc Schegerin, senior vice president of strategy, finance, and communications at ArQule.

This morning we issued a press release that reported results for the third fiscal quarter ended September 30, 2018. This release is available on our website at arqule.com. Leading the call today will be Paolo Pucci, chief executive officer at ArQule. Also present from the company are Peter Lawrence, president and COO; and Brian Schwartz, head of R&D; and Rob Weiskopf, CFO.

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Before we begin, please note that we'll be making forward-looking statements as defined in the Private Securities Litigation Act of 1995. These statements will include, among other things, projections regarding the timing of key events related to ArQule's proprietary pipeline. Actual results may differ materially from those projected in the forward-looking statements due to numerous risks and uncertainties that exist in ArQule's operations, development efforts, and the business environment, including those factors discussed in our reports on Forms 10-Q and 10-K and other documents filed with the Securities and Exchange Commission. The forward-looking statements contained in this call represent the judgment of ArQule as of today.

ArQule disclaims any intent or obligation to update any forward-looking statements, except to the extent required by law. We will provide an opportunity for questions and answers at the end of this call. I'd like -- now like to turn the call over to the CEO of ArQule, Paolo Pucci.

Paolo Pucci -- Chief Executive Officer

Marc, thank you, and thank you everybody for joining us this morning for today's call. The summer has flown by and has been a busy summer of work. During this summer, we strengthened our capital base and we progressed all of our clinical programs. We also have engaged with external advisors, so that we could refine the plans for our three key initiatives, which I remind you are: in liquid tumors with ARQ 531, particularly B-cell malignancies; in rare PI3KCA mutated diseases with miransertib; and in hormone-sensitive solid tumors with miransertib as well as ARQ 751, our next-generation AKT inhibitor.

The work that we have done this summer is aimed at realizing all three of these opportunity best as possible. Upfront, I would like to focus your attention on two very significant milestones that we achieved during this summer as well, and this is from the operational point of view. The first one is a scientific milestone and it has to do with ARQ 531. That milestone has been achieved with the publication of the preclinical body of evidence that supports the current clinical plan for ARQ 531 as the first and best-in-class reversible or dual wild type and mutated BTK inhibitor.

The paper was published by Dr. Byrd and Dr. Woyach of Ohio State University, and these are available in the paper Cancer Discovery. It's also available on our website.

I will be remiss not to thank all the collaborators at OSU, led by Dr. Byrd, for partnering with us three years ago now on the BTK project that has delivered over this years of hard preclinical work 531 as a clinical candidate. Without the support of our collaborator at OSU, we would not have been able to interrogate our BTK chemical matter as extensively as we have nd we wouldn't have been able to choose as good as a candidate as 531 is appearing to be more and more so in the clinic. The second, it's very close to our heart and it has to do with our rare disease program.

I do understand that that is not always the major focus of all of the people that participate in this call, but it is nonetheless a high focus of ours and of our collaborators. So, here as well, as you know, we've been working at rare diseases that are AKT driven for a number of years. And two weeks ago at the January meeting of ASH in San Diego, our collaborators and our self represented the first round of data that does two things essentially: validates further the data that has been developed by the NIH genetics for Proteus syndrome and also provides the initial proof-of-concept for the expansion strategy in PROS diseases. Both -- or rather this family of diseases is devastating family -- it is a devastated type of disease.

They manifest shortly after birth and they have a major impact on the lives of the children that are affected as well as their family. Here as well, I would like to thank our collaborator at the NIH genetics. Our collaborators are Bambino Gesu Pediatric Hospital in Vatican City, in Rome, Italy and also all the individual physicians that are on the ward have participated and care for their patients under our compassionate use program. Without their dedication, without their support, we would not be in the position to be the first company with a therapeutic that could begin to address this devastating as well as rare diseases.

Now having given these two highlights that presents the culminations actually of year awards, it's always a point in time, but this point in time is reached after many, many years of work. And those of you and some -- several on this call that have followed us over the year know that we have gotten to this place starting from a very long time ago. Now let me go over in greater detail the asset that most people -- that attracts the most interest, which is ARQ 531. And I have a fairly comprehensive update and I will try to also frame what is the data that can be expected for the next data release at ASH.

So, let me remind you first that the opportunity with ARQ 531, our dual BTK inhibitor -- reversible BTK inhibitor is to develop it as the first-in-class inhibitor of its kind. The challenge, as always when you are validating a new concept, is to break new scientific ground. And I hope that the pre-clinical data that has been presented in Cancer Discovery supports the analysis that some of the people on the scope form to assess our chances of establishing this new and higher ground for patients who are resistant to frontline irreversible BTK inhibitors. As we are in the clinic, it is customary for us to run a commercial assessment of the future potential of the drug.

So, during this summer we engaged with a premier consultancy to do just that. We assessed several indications and within each indication we assess where we could position in a clinical trial program the drug. And I'm pleased to report that we walked away from this exercise even more convinced that ARQ 531 has the potential to become a blockbuster commercial opportunity.As we approach ASH, I would like to highlight a few important aspects of the Phase 1 trial that we are conducting. Let me start with confirming that we plan to present at ASH data from cohorts one to six, and that would include the initial evaluation of clinical benefit.

For cohort No. 7, which we are currently dosing, we hope to provide initial PK NPD data. I will remind you that we've gotten every few months. And so, we are very unlikely to have any efficacy look for cohort seven.

We expect by year end to have treated in total 20 patients and we are very pleased on how this trial is proceeding. The primary objectives of this trial is to assess first safety, and then to establish MTD. We also have, as an additional objective, to assess signals of clinical benefit, particularly as we go into the higher-dose cohorts. Recall also that we decided not to conduct a Phase 0 healthy volunteer trial.

And that, therefore, we initiated this trial at comparatively lower doses as -- versus the doses that we would have initiated that -- had we had the benefit of a Phase 0 trial. The reason why we proceeded this way is because we were confident of the body of data that has emerged from a long investigation of the drug clinically and also because of the general scientific landscape around reversible BTK inhibitors. At ASH, therefore, in detail, this is what we plan to update on. Data from cohorts one, two, and three, respectively adults five, 10, and 15.

A preview of the data relative to these three cohorts was last offered at EHA in Stockholm, Sweden the past summer. Then No. 2, we plan also from these cohorts to present three patients that have been dose escalated since. Then we plan to present data from cohorts four, five, and six, dose respectively at 20, 30, and 45 milligrams QD.

This will be fresh data. We have not presented any of these data until now. And then, as I mentioned before, initial PK/PD data for cohort No. 7 that is currently being dose at 65 milligram QD.

Let me also remind you that that the last data presentation at EHA for cohort one to three provided positive information for PK/PD performance, provided some initial indication of clinical benefit, and most importantly, provided the first look at the safety of this compound in this first three cohort. Based on the initial observation we shared with many of you at EHA, we proceeded with two protocol amendments for the trial, one allowed for intra-patient dose escalation. I have received a number of questions on the side on this, so let me spend a minute to explain. As an example, assume that patient A enrolled in cohort one at 5 milligram.

Assume further that that patient demonstrate a clinical benefit. Then as soon as the following cohorts have been cleared for safety, then patient A can be dose escalated. So, that's how technically the trial works. Remarkably, as I mentioned, three patients have been dose escalated, one of them at least multiple times.

And these patients are important and that's why we will incorporate them in our presentation for ASH. Important for two reasons, because they will provide initial data correlating clinical benefit with dose changes, moving the dose upward as well as, and this is incremental versus our initial objectives for this trial, they will provide us data on long-term safety. One of these patients has been on therapy for many months. Then the second amendment it's a simpler amendment, but it's an important one as well.

So, the second amendment was to reduce the wash-out period from the last drug delivered to trial to five times the half-life of the last drug that had been administered. This amendment was intended to our ameliorate the challenge we are facing with this trial, where we are recruiting not so much the patient type that we would take in a Phase 3 trial. Second- and third-line refractory and mutated to frontline, but rather much later line of therapy. So, much more heavily pretreated patients that we would look to recruit in a registrational trial.

Finally, a trial planning we have projected based on preclinical modeling to achieve MTD in cohort seven. To date, the safety profile that has been observed for 53 -- ARQ 531 has exceeded the expectation and postponing potentially to a broader therapeutic window that we had anticipated for this drug and, therefore, to the possibility of dosing beyond the 65 milligrams that we are deploying in the currently being recruited cohort No. 7. The trial, as I mentioned, continues well and we're looking forward to update in greater detail at ASH.

The shell that we put for our ASH presentation was relatively bare because it was put in place many months ago, and now you have all the details of what will be fitted into that shell by the time of the presentation. So, I would not look at that shell presentation when it's going to come out as a point of reference for what is going to be presented. That was only the baseline and what is going to be presented now you have a full framework from this call. Let me then move to miransertib in rare AKT PI3K pathway-driven overgrowth diseases.

Here really we have -- we are shifting gear. We are shifting gear in a fundamental way. And although until now we have had mostly scientific partner, and I mentioned the most important ones: the NIH Genetics Group, the Bambino Gesu Hospital in the Vatican City and all the individual physicians. Now we have, if possible, an even more important partner that is beginning to dialogue positively with us.

And that's the regulators, that's the FDA. And today's FDA is very sensitive and is very receptive to the call, the effort that companies like us are making to provide therapeutic alternatives for rare disease, particularly for the [Inaudible], which are going overlooked because of the economics potentially of these diseases. So, how are we shifting gear with the rare disease? No. 1, we received fast-track designation from the FDA.

No. 2, we have also interacted already with the FDA, not really under the fast-track, but under a -- crosses that we already set in place. The fast-track going forward will simply facilitate and make that process of exchanging information and dialogue much more intensive, much more timely than it has been so far. And then we have presented, No.

3, at ASH confirmatory data of the potential utility of miransertib in Proteus syndrome. And No. 4, we have presented the initial match of data that provides proof of concept for the expansion strategy from Proteus syndrome to PROS. I hope that you concur with me in looking at these developments of the past months as shifting gear into a much higher gear.

And we intend to proceed with speed and purpose together with our regulatory -- regulators, partners from now on. Let me remind you that with miransertib the opportunity in rare diseases initially for Proteus syndrome is small, but it can be expanded, at least from the value point of view proposition, by the fact that miransertib has already received a rare pediatric disease designation that will lead eventually to a voucher. We are -- have -- as always is the case with ultra rare disease that are going unserved therapeutically, we are always challenged in defining exactly the epidemiology of -- that is in front of us. We are making the assumptions based on the literature that is available and based on the scientifically available data that Proteus syndrome is 100 -- 200 people -- patients opportunity, but we are also making the assumption that 200 patients could become up to 2,000 patients if the indication expanded to PROS.

For that reason, we are planning to proceed now in parallel. With two potential registrational efforts, one in Proteus syndrome, where we have a very strong compelling evidence and we have some clear understanding of what hard endpoints and soft endpoints could be in a registrational effort, and with PROS where we will need to engage in dialogue with the authority --  regulatory authorities to define both hard and soft endpoints for such an effort. So, finally we are entering a new phase for our rare disease strategy. Third, for miransertib and ARQ 751 in oncology.

As you know, we are in the process of recruiting an upsize cohort in endometrial cancer in combination with anastrozole for miransertib in hormone-sensitive tumors. And then as part of that strategy, and then for 751, we have selected 75 milligram QD as recommended dose for Phase 2 and further development. Let me remind you that for our AKT inhibitors in oncology, the opportunity is to sleverage the exquisitely selective profile, which is important, given that the opportunity for AKG inhibition in hormone-sensitive tumors is largely in combination with established standard of care. The challenge is to confirm timely the signals and proceed to occupy what white space might be available the -- in -- still in this hormone-sensitive tumors.

Now let me briefly talk about derazantinib and here I simply would like to report that we are on track in all the work that was planned to be executed with both of our partners, which are Basilea and respective -- for Rest of World, Greater China, where our partner is Roivant. So, as I mentioned, a very busy summer of work, a summer where we have dramatically escalated the scientific profile of ARQ 531 with the publication of the preclinical body of data in the prestigious publication that I mentioned and a summer where we really shifted gear with our strategy for rare disease. Now I would like to pass the call to Brian that will give you some further details beginning with ARQ 531. Brian, please?

Brian Schwartz -- Head of R&D

Thank you, Paolo. I will start with ARQ 531. As Paolo mentioned, ARQ 531 is a potent reversible inhibitor of both wild type and C481S mutated BTK. Our objective is to be the first reversible BTK inhibitor to market in B-cell malignancies where we are consolidating our clinical lead.

The most important development we have had this quarter was a publication of an extensive body of preclinical data in cancer discovery. I'm confident to say that with this publication plus data we presented at AACR and EHA, ARQ 531 is the best-published reversible dual BTK inhibitor currently in development. In this publication, we highlighted ARQ 531's novel biochemical selectivity profile and preclinical efficacy in both C481S mutated and wild type BTK CLL model systems. The effect of ARQ 531 on key signaling pathways and B-cell function was also evaluated relative to ibrutinib.

In addition to the in-vitro data, two in vivo models, both on the in-vitro data show efficacy in highly predictive CLL and rectal -- rictus model systems. As discussed by the authors, ARQ 531 is a molecule well suited to combat progressive CLL and with its unique profile demonstrates superior efficacy to the targeted ibrutinib therapy in the sectors of rictus transformation as well. The publication also includes ARQ 531's chemical structure and detailed crystallography, and I would like to point out a number of these defining characteristics. The core moiety forms a hydrogen bond with a hinge backbone and the unique chloride atom is positioned between A428 and K430 side chains.

Similar to ibrutinib, ARQ 531 occupies the hydrophobic pocket of the ATP binding region preventing signaling. The potent side chain facilitates a water-mediated extensive hydrogen bonding network. Importantly, 531 does not interact with C481, suggesting that the C481S mutation would not affect binding. I'll now move over to the clinical.

As Paolo mentioned, by year end we expect to complete dosing of at least seven cohorts in the first portion of the Phase 1a/b trial in patients with B-cell malignancies, including B-cell lymphomas, CLL, Waldenstrom's, who are refractory to all other B-cell therapies. The data title for ASH abstract being released tomorrow is early this summer with substantially more data will be presented at the meeting. In addition to safety, PK and clinical activity data at ASH, we plan to present the available pharmacodynamic data demonstrating ARQ 531's expected properties of dose-dependent effect on phosphor BTK and B-cell function. This is especially relevant considering the refractory nature of these patients to multiple lines of therapy including an irreversible BTK inhibitor such as ibrutinib or acalabrutinib for CLL patients.

Recall that we expect to enroll between 20 and 40 patients at up to four sites in the U.S in a standard three by three dose escalation scheme. We are very pleased with the progress we are making with this trial and I would like to especially thank the patients, our investigators and all the study staff for facilitating the brisk and timely accrual of patients onto the study. As we enter the final stretch of the Phase 1 trial, we are beginning to make plans for the next phase and we are looking forward to presenting the data at ASH. Next, I will touch on miransertib in rare overgrowth diseases.

Miransertib is a highly selective inhibitor with a downstream effect on AKT/PI3K. Our objective is to be the first and best AKT inhibitor in Proteus syndrome and the PROS family of rare overgrowth diseases. This family of diseases is ultra-rare, very heterogeneous, and the patients currently suffer from a dismal quality of life and early mortality. We are not aware of any other effective treatment or disease-modifying treatments that are currently approved.

I am pleased to report that several presentations by ArQule and our scientific collaborators were featured at the American Society of Human Genetics Congress in October this year. I'm also particularly proud of the work we are doing under ArQule's compassionate use program. In this program, we treated a patient in her teens with concomitant relapsed ovarian cancer and Proteus syndrome, both driven by the AKT1 genetic mutation. Miransertib was administered in a relatively high dose was well tolerated for over 19 months and resulted in clinically significant and durable positive response of the tumor, an improvement of the Proteus syndrome symptoms including improved mobility and bone changes.

The patient is doing well and currently still continuing on treatment. We have also presented at ASH the first cohort of approximately 10 patients from our Phase 1/2 corporate-sponsored trial in PROS. These data in their totality are important because they compromise a variety of patients and because the length of follow up that has been reported assures us on the safety profile of this drug in children as young as two years old. We have accumulated an extraordinary significant body of data for such a rare disease and we have now shared these data with regulatory authorities.

The FDA has responded by awarding us fast-track designation, for PROS and we are close to finalizing the registration plan for both Proteus and PROS syndrome. Next, I will discuss our AKT inhibitor miransertib and ARQ 751 in oncology. For these programs, at this time, I do not have much to add other than what Paolo has reported. In the Phase 1/b expansion cohort of miransertib with anastrozole in advanced endometrial cancer we continue to recruit and expect to have data early next year.

In addition, we will pre-presenting the full Phase 1 data set of ARQ 751 at the TRIPLE meeting in November. We are excited about the profile of the next-generation AKT inhibitor and have completed extensive work this summer with consultants to define a path forward for this drug in certain major and -- cancers with significant populations. With that, I would like to turn it over to Rob for the financial report.

Rob Weiskopf -- Chief Financial Officer

Thank you, Brian. The company reported a net loss of $5,619,000 or $0.05 per share for the quarter ended September 30, 2018, compared with a net loss of $6,666,000 or $0.09 per share for the quarter of 2017. For the nine-month period ended September 30, 2018, the company reported a net loss of $6,995,000 or $0.07 per share, compared with a net loss of $21,443,000 or $0.30 per share for the comparable nine-month period. At September 30, 2018, the company had a total of approximately $105,088,000 in cash, equivalents, and marketable securities.

Revenues for the quarter ended September 30, 2018 were $4,979,000 compared with revenues of zero for the quarter ended September 30, 2017. Research and development revenue for the quarter ended September 30, 2018 consisted of $2,852,000 from our February 2018 Roivant license agreement, $1,996,000 from our April 2018 Basilea license agreement, and $131,000 from a nonexclusive license agreement for certain of our library compounds. Revenues for the nine months ended September 30, 2018 were $22,823,000 compared with revenues of zero for the nine months ended September 30, 2017. Research and development revenue in the nine months ended September 30, 2018 consisted of $5,852,000 from our February 2018 Roivant license agreement, $15,702,000 from our April 2018 Basilea license agreement, and $1,269,000 from a nonexclusive license agreement for certain of our library compounds.

Taking a look at expenses, research and development expense in the third quarter of 2018 was $7,261,000, compared with $4,570,000 for the third quarter of 2017. The $2.7 million increase in research and development expense was primarily due to higher outsourced preclinical, clinical, and product development costs. Research and development expense in nine months ended September 30, 2018 was $19,860,000, compared with $14,747,000 in the comparable period in 2017. The $5.1 million increase in research and development expense in the nine-month period was primarily due to higher outsourced preclinical, clinical, and product development costs.

General and administrative expense was $3,429,000 in the third quarter of 2018, compared with $1,762,000 in the third quarter of 2017. The $1.7 million increase in general and administrative expense in the third quarter was primarily due to higher consulting and professional fees of $1.4 million in labor and related costs of $0.2 million. General and administrative expense was $8,014,000 in the nine months ended September 30, 2018, compared with $5,702,000 in the comparable 2017 period. The $2.3 million increase in general and administrative expense in the nine-month period was principally due to a higher consulting and professional fees of $1.8 million and labor and related cost of $0.5 million.

Turning now to guidance, as a result of our advancing development programs and collaborations, and the likely timing of cash receipts and disbursements, we've updated our 2018 guidance. Net use of cash is expected to be approximately $34 million for the year, which is slightly higher than our previous guidance due primarily to an acceleration of the clinical development programs associated with proprietary and partnered clinical programs. Net loss is expected to range between $14 million and $17 million for the year and net loss per share to range between a loss of $0.14 to $0.17. We are also adjusting our revenue guidance upward to between $24 million and $25 million, primarily in connection with services provided to our derazantinib partners.

ArQule expects to end 2018 with approximately $100 million in cash and marketable securities, which we believe will be sufficient to finance our operations into 2021. With that, I would like to hand the call back to Paolo.

Paolo Pucci -- Chief Executive Officer

Thank you. Operator, we can open for questions, if there is any. 

Questions and Answers:

Operator

[Operator instructions] And our first question comes from a lot of Jonathan Chang of Leerink Partners. Your line is now open.

Jonathan Chang -- Leerink Partners -- Analyst

Hi, guys. Thanks for taking my questions --

Paolo Pucci -- Chief Executive Officer

You're welcome.

Jonathan Chang -- Leerink Partners -- Analyst

-- and for [Inaudible] additional color ahead of the ASH update. That was very helpful. For first question, for ARQ 531, can you expand on your thinking around possibly dose escalating beyond cohort seven?

Paolo Pucci -- Chief Executive Officer

It's pretty much as we said, Jonathan. We like to see an MTD, if we can, whether -- in the context of all the other data. As you know, we started conservatively in dosing because of not having perform a Phase zero study, but also because this is a potent drug that has a spectrum selective kinase profile. So, it's very much related to how the data will flow.

Not know much more than what we have said so far in this call. Brian, anything to add?

Brian Schwartz -- Head of R&D

No. I think we just like to determine some cost of therapeutic index and to date we haven't seen any safety signal or safety warning signal that will suggest we should not increase the dose and determine what the full therapeutic window will be.

Paolo Pucci -- Chief Executive Officer

And that is also in the context of some of the initial signs of therapeutic benefit we have already shown at -- in the EHA presentation. The other point of reference you want to keep in context is we have three patients that have been dose escalated from earlier cohorts and, of course, I can't comment a lot about those patients right now because they're for the ASH presentation, but I will also provide some further context on why we'd, if possible, if we have -- if the drug approves to have a slightly broader therapeautic window we had originally anticipated, we'll dose further. Remember that all was based -- at this stage for every drug, you extrapolate the preclinical work. So, we thought of putting together that -- in the public domain that preclinical work in the Cancer Discovery publication.

That's the context we can provide right now.

Jonathan Chang -- Leerink Partners -- Analyst

OK. Great. That's helpful. Second question...

Paolo Pucci -- Chief Executive Officer

But it's -- in my view it's about the context, particularly because there has been discussions not related to our drug, but related to other inhibitors in development about the safety profile. So we wanted to clarify where we are with our observations, thus far, until today, until now, I would say.

Jonathan Chang -- Leerink Partners -- Analyst

Got it. Thank you. Second question, how are you thinking next steps following the 531 dose escalation study? What could a fast path to registration look like?

Paolo Pucci -- Chief Executive Officer

So, for the next steps that's where we have worked, December, with this consultancy. And we have, of course, a major object -- so, we have two potential patient population, which is the primary target patient population, which is the population that is mutated from early use of an irreversible inhibitor frontline being ibrutinib or being acalabrutinib. So, there is -- and I confirm, I would say nothing new versus what I've said in the last few calls is that the fastest market opportunity we assume it to be the third-line patients that have progressed through ibrutinib, say through potentially [Inaudible] combination and have mutated. I wish we had been able already in this trial to recruit all the patients like that, but we have been able, thus far, to recruit patients that are much more refractory in [Inaudible] settings.

There is also an opportunity to engage with the regulators in discussion of whether a biomarker-defined population would provide an opportunity for second line and whether that second line opportunity will have to be an uncontrolled trial, as I assume, it might be for third line or have to be a controlled trial. So -- and now speaking of CLL, to talk about that universal indications that where ibrutinib is front line therapy and where we see resistance development. And then there is the non-ibrutinib related B-cell malignancies and that I can comment -- I will be able to comment more as we accumulate more data. So that's a path forward.

What I can say is that for a number of reasons we wanted to enhance our level of understanding of the commercial opportunity. And that's why we engaged the consultancy to understand that because when you are in dialogues with a number of parties including investors, you want to be well-educated about that commercial opportunity. And I have to say that the commercial opportunity could be quite significant. And the white space provided that the resistance remains -- it continues to grow as one would expect based on other [Inaudible] such experiences, it's also white space.

So, it's a better commercial opportunity I've seen in a while, to be honest.

Jonathan Chang -- Leerink Partners -- Analyst

Right. Thank you. Maybe just one last one from me. How easy or not is it to find C41S new CLL?

Paolo Pucci -- Chief Executive Officer

We have not had issues. We have not have any issue. The challenge that we've had has been not just to find the patients, but to find patients that have recently -- that have progressed from ibrutinib at the second line and/or third line. We are finding patients that are five, six lines of therapies past.

That's just been the challenge, but not -- we have not had a challenge in finding -- patients that are mutated. Now obviously you have to take this one with the frame work of having recruited 20 patients in a year or so, but that has been our experience. Within those numbers that has been our experience so far.

Jonathan Chang -- Leerink Partners -- Analyst

Great. Thank you very much.

Paolo Pucci -- Chief Executive Officer

You're welcome. I think what helps us also is that we are so well published. So, the fact that the drug is so well published and the fact that the drug has shown already at EHA initial sign of clinical benefit at clearly therapeutic doses if you look at PK/PD and the fact that the drug is essentially first-in-class right now if you look at the clinic. All these elements have probably contributed to define our experience having issues in recruiting.

And I would -- last, but not least, definitely not least, the fact that we are -- our trial pivots around Ohio State Cancer Center, the [Inaudible], where Dr. Byrd has pioneered both the irreversible inhibitor and he is now with our drug pioneering the reversible inhibitor. So, the fact that we're not having issues might be related to our circumstances, but that's how it is.

Brian Schwartz -- Head of R&D

I'd just like to add something, Jonathan. Within feasibility and expanding the trial to multiple other sites and based on the informal feasibility assessment there appears to be an increasing number of C481S mutant patients at big academic sites.

Jonathan Chang -- Leerink Partners -- Analyst

Thank you.

Paolo Pucci -- Chief Executive Officer

Sure.

Operator

Our next question comes line from the line of Chad Messer of Needham & Company. Your line is now open.

Chad Messer -- Needham & Co. -- Analyst

Thanks. Good morning and thanks for taking my question.

Paolo Pucci -- Chief Executive Officer

Good morning, Chad.

Chad Messer -- Needham & Co. -- Analyst

Good morning and congratulations on the tremendous progress this year.

Paolo Pucci -- Chief Executive Officer

Thank you.

Chad Messer -- Needham & Co. -- Analyst

I was just wondering for 531 if it's possible for you to share with us what potential expansion arms might look like in the one besides C481S mutants, if you're considering any? And also when we might expect these arms to start enrolling? I know at one point in the past we were targeting by year end, but it sounds like you guys have more dose escalation to do.

Paolo Pucci -- Chief Executive Officer

So we -- the process has not stopped and we are running in parallel the process of completing the Phase 1/a part as well as planning for the next stage. So, you've heard from me that we have run already all the commercial screen to identify what the next steps might be. You've heard just now from Brian that we are doing the feasibility for expansion study. I would say that our primary effort is going to be to remain first and best, right? As part of being best, we are trying to provide as much the scientific data as possible to support that position.

The Cancer Discovery paper, we have -- we had committed to present the data as it will flow in and I remind you, Chad, we presented at ACR already. We presented at EHA already and we are presenting at ASH as well and we're presenting at ASH essentially what we had committed to present. So, it's a little bit premature for me to add more than what I have told Jonathan. In our effort to remain first and best, the focus is on the primary target patient population, which is mutated from frontline whether that's going to be a third-line effort followed by a second-line effort or whether it's going to be to concomitant efforts, that's going to be the primary thrust of focus.

Now that said, the early cohorts have allowed us to recruit patients that are of a next-stage expansion, like the lymphomas. And some interesting data, which we had shared with you at ASH, at EHA already has emerged and now you're going to see a little bit more data from those patients. Those -- that data might point to additional expansion opportunity for the Phase 2, but that will not be the primary thrust at this point in time. That's as much as I can answer your question right now, but rest assured that the work -- the planning work has been done.

Chad Messer -- Needham & Co. -- Analyst

All right. Thanks. Understood. And then just on derazantinib, I know that's in the hands of your partners, and just your update was extremely brief.

I was wondering if there's any more you can tell us about the study that you guys had gotten started. I know there had been plans -- in the past you shared for interim look. Can we still expect that and potentially when?

Paolo Pucci -- Chief Executive Officer

The -- I think I need to refer you to our last disclosure because any incremental disclosure will have to come from our partners, but the FDA [Inaudible] this is our class continues to proceed well and to the best of our knowledge the same is for the trial we had initiated, which has now been transferred to Basilea. So, we had expected updates in the early part of next year, that was our last disclosure. And so I will have to refer you to Basilea for further disclosure. As far as Roivant, they have proceeding -- they are proceeding in a very timely manner to initiate clinical work in China, I would say.

We're very pleased with that as well.

Chad Messer -- Needham & Co. -- Analyst

All right. Great. Thank you, Paolo.

Paolo Pucci -- Chief Executive Officer

No problem. Thank you.

Operator

And our next question comes from the line of Jotin Marango of ROTH Capital. Your line is now open.

Jotin Marango -- ROTH Capital -- Analyst

Good morning, team, and congrats on the string of presentations this year. One more to go.

Paolo Pucci -- Chief Executive Officer

Thank you. Thank you. Two more to go, two more, two more, two more. First [Inaudible] and then ASH.

We are busy here.

Jotin Marango -- ROTH Capital -- Analyst

I can't -- we can't keep track anymore, Paolo. So, the question -- my questions about the BTK program were mostly asked and answered. I would like to confirm one thing though about the protocol amendment that came after EHA. And the question is the following: if a patient is escalated from 5 milligram taken up 30, let's say, as a hypothetical example, that patient in the analysis is going to be counted in the three-person cohort for 5 milligrams for the time that he was under 5 milligram, but will not be counted in the three-person cohort at 30.

However, he could be added as a fourth person to that analysis. Is that correct?

Brian Schwartz -- Head of R&D

Yes.

Paolo Pucci -- Chief Executive Officer

Yes, correct.

Brian Schwartz -- Head of R&D

It's going to be very hard to interpret. You're right. When your dose escalates, it's easy to see efficacy because if you increase dose, you can see PK/PD efficacy. It's very hard to say safety.

So the safety -- we understand with dose escalating, you sometimes compromise safety because you always have to assume that the lower dose you're going to have much less data on them than you would have if you kept them on that dose. But we found -- for this class of drug in our initial discussions with the FDA also, they felt that it's important to get the PD -- get -- make sure that the dose you're giving patients is above the dose in which you get full BTK knock down.

Jotin Marango -- ROTH Capital -- Analyst

Understood. Thank you. And turning the wheel a little bit to the data that you just presented in San Diego in overgrowth syndrome, you mentioned earlier during the remarks that at this point in Proteus with the inhabitants of hard and soft endpoints, which could be taken forward, could you give us maybe a little more detail on sort of what your view as a potential hard and soft end point there that could be taken through -- onto a registrational study. And then related to that when we think about the larger add-on opportunity here in the -- that the other syndrome, instead of the overgrowth syndrome at large, is there an example out there of in the ultra-orphan space of first therapy that was directed at the basket of condition, which we could then sort of think as we consider timelines and endpoints? Thank you.

Paolo Pucci -- Chief Executive Officer

So, I'm going to let Brian answer the basket question, I'm going to take the first two. So first of all, the data that we presented at EHA, for those that haven't gone through that in detail, for Proteus syndrome we have two sets of data. A set of data from the NIH that was presented a year ago at the Patient Association by Dr. [Inaudible] and we hope to be impressed in print very soon.

And then we had data that we have been developing in parallel through compassionate use. At EHA -- sorry at ASHG in San Diego, we presented patient actually our collaborators of Gemelli hospital in Rome presented one patient to us is a demonstration patient. It's a young woman, a teenager girl, that had both a Proteus syndrome and ovarian cancer that was AKT1 driven genotype. So, this was the one patient, where we could demonstrate the utility of miransertib in two coexisting diseases, both AKT1 driven.

While that patient was taken on therapy about a year and a half ago, after she was heading for, unfortunately, hospice. In a year and half thereafter, you've seen the presentation at EHA -- sorry at the ASHG and what you see, the cancer is essentially in remission, is a beautiful PR. And that the [Inaudible] Proteus syndrome is greatly improved. Now that patient does not offer insight in the hard endpoints.

So let me go through the second part of your question, without the potential hard endpoint. For PROS -- Proteus syndrome, potential hard points has emerged primarily from the NIH work because the NIH demonstrated in three pediatric patients that the cerebriform masses under the feet can be assessed over time as it develops or otherwise with therapy through some formal standardized photographic evidence. You have seen some photographic evidence of the regression of the disease in the hands of the patients in -- that I just mentioned, that we presented at the ASH meeting. So the cerebriform -- the development of the cerebriform masses on the feet of the patients could be through photographic evidence, a potential hard endpoint for Proteus syndrome.

There are a number of additional endpoints that can also be conceded, but they would not be -- they are softer endpoints. For PROS, the challenge is a little bit more complex because PROS the manifestation of PROS is it doesn't have a harbinger manifestation like the cerebriform masses under the feet. So probably pure photographic evidence might not be just the only hard point. There might have to be some form of photographic and radiographic hard points.

That discussion we will need to have. And so this is as much as I can tell you about the endpoints. Complex diseases, so very happy to have the designation that allows us to interact with the FDA. As far as examples of basket trials in rare diseases, I am not the expert.

I don't recall any case that will be so close to what we would look at.

Brian Schwartz -- Head of R&D

So just, Jotin, maybe I can just give a little bit of color. At ASHG and moving forward, there's a lot more understanding of somatic mosaic mutations of PI3K AKT or P10, which could result in these -- this basket of overgrowth diseases as more understanding, more drugs that inhibitors power-play are being tested. AKT being central is the only drug that could really affect all the PI3K, all the AKT, and all the P10 [Inaudible] disorders. So that it gives us a unique opportunity to affect that whole basket.

Other drugs could have an impact. We also know that from our cancer experience and from our preclinical work with [Inaudible] that there's a negative feedback loop sometimes when you block [Inaudible], you can sometimes up regulate and make these diseases worse. So, we know that mTOR blockade can help sometimes and not help on other drugs. But it is a growing area of increasing scientific body of knowledge.

We see ourselves well-positioned to be the first group to go off this syndication and we are trying to incorporate, as it is rare, the biggest group of patients possible in both our clinical trials.

Paolo Pucci -- Chief Executive Officer

We are essentially breaking such new ground with this, Jotin, and that we are kind of in the wilderness for the last three years and really we had to work on phase and stay committed. The regulatory -- the changing piece of our regulatory interactions and the kind of acceptance that we have had in beginning our formal interaction with the regulators is really the most encouraging development we've had other than data in the recent date. But I think which should related to your question, which is a very good one, about how one proceed with getting a drug approved for a basket of diseases. In your question there is also the reason for the strategy we have declared, right, Jotin? Because we will be -- we are breaking already new ground for Proteus syndrome.

We will be breaking even more new ground if we were to pursue only PROS family as diseases. We have intended to derisk a little bit the regulatory interactions by working in parallel to Proteus and PROS. The other thing that has led us to think that way is that for Proteus syndrome specifically we have the rare pediatric disease designation. And so we have a very significant economic milestones for our shareholders to achieve and that's the reason why we -- that's another reason why we had to proceed that way.

Sorry, I don't have more about the basket, but we -- I'm sure we will revisit it over time. Marc, you have a comment on the rare disease, please.

Marc Schegerin -- Senior Vice President of Strategy, Finance, and Communications

Yes, I [Inaudible] although we could refer to it as a basket in a sense. The fast track designation was given to the PROS syndrome collectively and to some extent it's a basket in that there are different mutations in the same gene, which can lead to PROS, it still is the same gene. So there's many -- it's different than a basket trial in oncology, for example, where you're enrolling truly different solid tumors, for example, that harbor the same mutation targeted by the same drug. This is a drug that will be going after a syndrome caused by mutation in the same gene.

So you see that in DMD, you see that in other cases. So on the one hand it's a basket because the phenotypic changes observed in these patients vary, of course. Still it's a fairly well-defined population of genetic alterations because it's really an alteration in the same gene -- different alterations in the same gene that we're targeting.

Paolo Pucci -- Chief Executive Officer

Thank you, Marc.

Jotin Marango -- ROTH Capital -- Analyst

Great. Thank you very much. See you at ASH.

Paolo Pucci -- Chief Executive Officer

You're welcome. See you there. Take care.

Operator

Our next question comes from the line of Hartaj Singh of Oppenheimer. Your line is now open.

Unidentified speaker

Hi. Good morning. This is Emma on for Hartaj.

Paolo Pucci -- Chief Executive Officer

Good morning.

Unidentified speaker

Just to follow up on [Inaudible] -- good morning. Would you consider seeking a partner in other -- Proteus approach for the studies or for the commercialization if it does get approved there?

Paolo Pucci -- Chief Executive Officer

We -- Emma, I would say we were always open and we're -- remain opened to discuss anything with anybody. Our [Inaudible] in the best interest of our shareholder, is it in best interest of our patients? Those are the constituencies we look at when we assess. You would argue that with the exception, as you correctly pointed out, of the rare disease potential partners could significantly expand and accelerate more to work of that we're planning to do with AKT 741 and potentially 531 in oncology as well as 531 in hematology as well. That's as much as I can say.

It's -- I'm sorry to not to be more specific. It's just a general policy. We keep an open mind. Sometimes this company -- go ahead.

Unidentified speaker

I guess, to ask it another way. From a resource perspective, do you feel that you could fully develop and commercialize the rare disease indications specifically yourself.

Paolo Pucci -- Chief Executive Officer

So, for the rare disease I think in terms of developing it, we do. It all depends also, Emma, on the context because we -- the work we have done -- so there is -- so let's say like this, there is in terms of priority, there is very significant white space for 531. So, 531 could absorb an enormous amount of resources is one wanted to press beyond the fast market opportunity, second and third line CLL. And you could argue that if -- particularly if the drug continues to provide -- show itself safe and effective, that space is only going to expand.

For -- and the same thing can be said for the AKT inhibitors where you are talking about breast cancer, ovarian cancer, granted that there will be subset, but these are subset of breast cancers, large -- talking of subset of prostate cancer as well. So, it's very difficult for me to provide a clear answer to the question as of yet, so no. It's all in context, but in principle the rare disease species, the one that least likely would benefit from a partner. As a development program, as a commercial program, there will be a different story.

For Proteus and it will be the commercial model. Proteus syndrome is so rare that you could envisage a worldwide distribution model, so to speak. If we were to chase PROS, and if PROS proved to be 2,000-plus patients, then we will have to ask ourselves the question. But development wise, I think we can support that effort on our own.

It will not be incrementally better by taking a partner on. The other two programs might be incrementally better by taking a partner on, but it will also depend on the partner, right.

Unidentified speaker

Great. No, that's helpful. And then just one follow-up on 531. Could you provide any thinking on, I guess, response rates that you have to see at ASH, what an appropriate compared or a hurdle might be there, given the popular -- patient population you're studying versus that of the approved BTK inhibitors?

Paolo Pucci -- Chief Executive Officer

So, the benchmark that we have, we haven't looked at any benchmark because there's not really one established for these patient population. So we like to see some -- we would like to see the body of data proceed all in the same way and to begin to see clinical benefit. So, improved clinical benefit versus what we have observed so far at EHA. So if we see, for us, we will be encouraged by seeing incremental benefit vis-a-vis what we presented at EHA, which is the only benchmark that we have right now for ourselves because there's not much that has been done.

The only caution there would be that we are taking patients that are very rare refractory more so than the second and third line patient. That's as much as we could see. That's as much as we can say for now. Also remember there are some technical aspects you can see there.

As you know there are some indicators that go up and then with first [Inaudible] and then they go down over time. And whatever efficacy we'll see will have to be using the context of how many scans have been administered to define that efficacy, right.

Unidentified speaker

Great. Thanks.

Paolo Pucci -- Chief Executive Officer

It's -- we're expecting to see incremental benefit versus what we have presented at EHA. That's our hope.

Operator

[Operator instructions] Our next question comes from the line of Mathew Cross of Jones Trading. Your line is now open.

Mathew Cross -- Jones Trading -- Analyst

Hey, guys. Congrats on the quarter and really looking forward to these couple of readouts coming over the next month or so.

Paolo Pucci -- Chief Executive Officer

Thank you.

Mathew Cross -- Jones Trading -- Analyst

So a couple of questions here. First was looking at your recent ASHG data on Proteus and PROS with miransertib, I was wondering about a couple of things. First, if you could discuss whether you feel you need to do any kind of further dose finding work either prior to or in Phase 3? Given that, I guess, all eight patients from that recent run search of data set in PROS ended up escalating from the base 15 milligram per meter squared to the higher 25 milligram per meter squared dose. Or do you feel that insights from the data in the time period following that dosage increase were sufficient to combat that 25 milligram per meter squared, the dose taken in Phase 3?

Brian Schwartz -- Head of R&D

Matt, I think we've sufficient data. We [Inaudible] to move forward, our principle with this disease is to try and move forward with the lowest possible dose to keep the disease in check. So, we think we have sufficient data based on the whole body of data including the NIH's data to move forward with a starting dose. We will allow a dose increase and that will be built into the study.

But although we've got enough data to start and have a recommended dosing schedule for patients throughout the trial.

Mathew Cross -- Jones Trading -- Analyst

OK. Great. That's very helpful. And then kind of a follow up on that, you mentioned obviously you're going to be looking at two side by side trials for Proteus and for PROS.

And so, I was just kind of curious if you could address or maybe go into a little more detail on any unique differences you feel you may need to address for between these two indication groups that would warrant two larger separate trials, given that the PROS as it is already kind of a basket indication as been discussed this morning. Why breaking up this disease into chunks?

Brian Schwartz -- Head of R&D

So I will tell you, in discussion with the agencies the difficulty is to try and do -- they're more appreciative of a small number of patients done in a uniform way rather than a large number of patients done with different measures. So for example, if you could find a common measure in a group of PROS patients, that would be much better than saying a bigger number of responders using multiple different methods. So for Proteus, the NIH has published already the method that we could easily use with photography. With PROS, there's already an increasing body of data suggesting imaging volume could be easily used.

So, it's just splitting the two in defining what a response is for each different group and moving forward with that in the trial.

Mathew Cross -- Jones Trading -- Analyst

Great. OK. That makes sense. I appreciate you going into that detail.

Second one, I was kind of -- third, I guess, was kind of another two-part question here. Thinking about your AKT programs, we've seen some kind of tentative but directional change in treatment patterns in these hormone-sensitive tumors to utilize a second round of treatment with aromatase inhibitors with first and second line rather than simply front line before moving on to some kind of applicable chemo. So with 751 dose escalation results coming up and as you're recollecting more data on both 751 and miransertib in combination with anastrozole, is there anything you can say about what you're hoping to see from these two trails or to kind of delineate rules for both of these AKTs within oncology and rare disease, and then also if you believe this kind of gradual shift in treatment patterns may broaden the market for whichever AKT inhibitor you take forward in these hormone-sensitive tumors, two multiple lines of therapy.

Paolo Pucci -- Chief Executive Officer

So on a broad base the more the data -- the more miransertib entrenches itself as a rare disease drug, the more we're going to be inclined to bring you forward just as a rare disease drug. With -- maybe one exception that will be diseases where AKT is important and it's important to have an AKT that crosses the [Inaudible] barrier. The more 751 demonstrates to be a more potent, a more selective and the AKT inhibitor into have a better therapeutic window, the more that drug will be positioned in oncology. This is the broad thinking that we're applying to answer your question.

But our final answer is not there yet.

Mathew Cross -- Jones Trading -- Analyst

Sure. And then as far as using multiple line of therapies with aromatase inhibitor, is there any kind of thinking about whether that may be possible reparable for whichever AKT is taken in oncology?

Paolo Pucci -- Chief Executive Officer

Yes, of course, of course, of course. I think for AKT, if I remember correctly, there is the leader in development -- in developing AKT inhibitors in that setting is Genentech right now and that if I remember well the last presentation they offer as an update to their pipeline they're expecting readout within the next two years from both of their trials currently in prostate cancer and breast cancer combinations. So that there is a challenge -- there's an opportunity to challenge because obviously they'll occupy a market. It's an opportunity because we may eventually validate.

But the answer to your question, yes, that's one of the alternatives that we have considered in the exercise ran this summer to define a path forward in oncology for whichever of the two.

Mathew Cross -- Jones Trading -- Analyst

Perfect. I appreciate that. And very much looking forward to the results in November and ASH. See you guys then.

Paolo Pucci -- Chief Executive Officer

Thank you as well. Bye, bye.

Operator

[Operator instructions] Our next question comes from the line of George Zavoico of B. Riley FBR. Your line is now open.

George Zavoico -- B. Riley FBR -- Analyst

Hi. Hi, everyone. Thanks for all the details and good progress -- good progress clearly.

Paolo Pucci -- Chief Executive Officer

You're welcome.

George Zavoico -- B. Riley FBR -- Analyst

Just a couple of really quick questions. So the compassionate use in Proteus, any new patients enrolled for compassionate use and what's the total number so far in compassionate use?

Paolo Pucci -- Chief Executive Officer

For Proteus, we are considering a couple of requests right now that might be -- that we might have to satisfy because it's going to be difficult geographically to direct them to the clinical trial we are hoping to open. And I think in the totality, Proteus patients treated is just shy of 10.

Brian Schwartz -- Head of R&D

In the total --

Paolo Pucci -- Chief Executive Officer

In the totality.

Brian Schwartz -- Head of R&D

Ttotal compassionate use program, yes.

George Zavoico -- B. Riley FBR -- Analyst

That was just shy of 10?

Paolo Pucci -- Chief Executive Officer

No, the totality of the patients treated is shy of 10, including the NIH. In the compassionate I think we got --

Brian Schwartz -- Head of R&D

Well, compassion -- so we presented the one patient, George. And then we have another four Proteus patients treated.

Paolo Pucci -- Chief Executive Officer

Yes, in compassionate.

George Zavoico -- B. Riley FBR -- Analyst

So five altogether in compassionate?

Brian Schwartz -- Head of R&D

Yes.

George Zavoico -- B. Riley FBR -- Analyst

OK. Thanks for that. Also speaking of 531, and your dose escalation is a different cohorts and the ability to promote or move someone in lower cohort into higher cohort. How many patients are eligible for that kind of movement? Is it -- you say you have to skip a cohort. In other words, you can't go for -- you can't escalate from three to four.

You have to go from three to five. If you're in the middle of six, I'm figuring -- sorry?

Paolo Pucci -- Chief Executive Officer

No -- so all that we can comment, George, for that is that there are three patients that have been dose escalated from cohorts one to three to higher doses. And the high-end of this is up to the dosage of cohort No. 6, which is 45 milligram. That's all we are saying.

Brian Schwartz -- Head of R&D

But practically speaking, George, a patient -- you clear a cohort, you wait for that patients at the lowest cohorts, tumor evaluation, and then you make a decision to dose escalate. So, it really depends if those two periods -- when those two periods fall, it could be a month after you clear the cohort, it could be two months after you clear the cohort.

George Zavoico -- B. Riley FBR -- Analyst

OK. So, but the bottom line is that nine patients were in cohorts one to three and of those three of them dose escalated. So you're having about a 33% rate of patients that go up to dose escalation. And these are the lowest dose cohorts where maybe you didn't expect to see any sign of efficacy. When you plan the trial, like you said, you didn't do healthy volunteer.

So probably the first three cohorts, you didn't expect to see very much. So this is a bit of a surprise?

Paolo Pucci -- Chief Executive Officer

It's -- I would say that it is a positive sign. Definitely, it's a positive sign for the reasons that we discussed and the reason you're highlighting. I would note though that two of those patients were lymphoma patients, I think, and which is -- one lymphoma patient and two CLL, one of the CLL was mutated. So, yes, I mean, overall it's as we described in the fourth day.

It was positive and it is a positive that we are seeing continued solid safety both from the early cohorts, from the later cohorts, and from the patients that have been dose escalated.

George Zavoico -- B. Riley FBR -- Analyst

OK. And the final question, just to clarify, you're talking about the fast track for PROS, right. It's the fast track for PROS not Proteus?

Paolo Pucci -- Chief Executive Officer

Well, Proteus is part of PROS, so we can discuss in that context, Proteus as well as a separate entity. And as Brian said, the regulators have a tendency at least for the initial indication to want -- to prefer more homogeneous groups.

George Zavoico -- B. Riley FBR -- Analyst

OK. Just to clarify, Marc, mentioned that there was mutations in one gene, presumably the AKT gene but the PROS syndrome also includes PI3K and P10 mutations.

Brian Schwartz -- Head of R&D

Just the PI3K, yes. The acronym for PROS George is PI3K CA-related overgrowth syndrome. So for the most part, although phenotypically, especially before the identification of the specific gene mutations, they may have been comped together. But you're right, PROS is genetically related to PI3K CA mutations. Whereas Proteus is typically an AKT1, again a function mutation.

George Zavoico -- B. Riley FBR -- Analyst

So, but the fast track then covers mutations in two different genes?

Brian Schwartz -- Head of R&D

FDA requested that we split the two. So we have done -- we've got four Proteus, we have orphan drug and pediatric voucher designation. For PROS, we have the fast track, but we have one IND for both. So we have the ability to discuss everything under the one IND.

George Zavoico -- B. Riley FBR -- Analyst

OK. All right. That clarifies it. Thank you very much.

Paolo Pucci -- Chief Executive Officer

You're welcome, George.

Operator

And I'm showing no further questions at this time. I would now like to turn the call back to Marc Schegerin for closing remarks.

Marc Schegerin -- Senior Vice President of Strategy, Finance, and Communications

Thanks all very much for joining. That concludes today's call.

Operator

[Operator signoff]

Duration: 83 minutes

Call Participants:

Marc Schegerin -- Senior Vice President of Strategy, Finance, and Communications

Paolo Pucci -- Chief Executive Officer

Brian Schwartz -- Head of R&D

Rob Weiskopf -- Chief Financial Officer

Jonathan Chang -- Leerink Partners -- Analyst

Chad Messer -- Needham & Co. -- Analyst

Jotin Marango -- ROTH Capital -- Analyst

Mathew Cross -- Jones Trading -- Analyst

George Zavoico -- B. Riley FBR -- Analyst

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