Good morning. And welcome to Oncolytics Biotech's First Quarter 2023 Conference Call. All participants are now in listen-only mode. There will be a question-and-answer session at the end of this call. Please be advised that this call is being recorded at the company's request.

I would now like to turn the call over to Jon Patton, Director of Investor Relations and Communications. Please go ahead..

Thank you, operator. And good morning everyone. Earlier this morning, Oncolytics issued a press release providing recent operational highlights and financial results for the first quarter and full year of 2023.

A replay of today's call will be available on the Events & Presentations section of the Oncolytics website approximately two hours after its completion. After remarks from company management, we will open the call for Q&A.

As a reminder, various remarks made during this call contain certain forward-looking statements relating to the company's business prospects and the development and commercialization of pelareorep, including statements regarding the company's focus, strategy and objectives, company's belief as to the potential and mode of action of pelareorep as a cancer therapeutic, the design, aims and anticipated benefits of the company's current pending clinical trials, and anticipated timing of the release of additional data, the company's plans and expectations regarding potential registrational studies, company's business development plans and strategies, company's financial runway, and other statements related to anticipated developments in the company's business.

These statements are based on management's current expectations and beliefs and are subject to a number of factors, which involve known and unknown risks, delays uncertainties and other factors not under the company's control that may cause actual results, performance or achievements of the company to be materially different from the performance or expectations implied by these forward-looking statements.

Any new forward-looking statement in which Oncolytics expresses an expectation or beliefs as to future results, such expectations or beliefs are expressed in good faith and are believed to have a reasonable basis, but there can be no assurance that these statement or expectation or belief will be achieved.

These factors include results of current or pending clinical trials, risks associated with intellectual property protection, financial projections, actions by regulatory agencies and those factors detailed in the company's filings with the SEDAR and the SEC.

Oncolytics does not undertake any obligation to update these forward-looking statements, except as required by applicable laws. Speaking on today's call will be Oncolytics' Chief Executive Officer, Dr. Matt Coffey; Chief Medical Officer, Dr.

Thomas Heineman; Global Head of Business Development, Andrew de Guttadauro; and Chief Financial Officer, Kirk Look. I will now turn the call over to Matt to begin management's remarks. Please go ahead, Matt..

Thanks, Jon. It's my pleasure to provide an overview of our recent highlights and outlook for the coming months.

I will start with the exciting news that came out just last week when we announced the results from our randomized BRACELET-1 trial in HR-positive/HER2-negative metastatic breast cancer will be shared in an oral presentation at the upcoming ASCO Annual Meeting.

ASCO is one of the world's most well-regarded oncology conferences and will provide an excellent venue to discuss our results with potential partners and the broader breast cancer community. With BRACELET’s ASCO abstract set to be published later this month, we are weeks away from a crucial milestone to pelareorep or Pela, as I'll often refer to it.

As I have mentioned on previous calls BRACELET-1 represents Pela's last major step on the path to a pivotal study in HR-positive/HER2-negative metastatic breast cancer.

Key goals for the trial are to inform and design a subsequent licensure-enabling study and to validate prior randomized Phase 2 data that showed Pela driving a statistically significant near doubling of median overall survival when combined with paclitaxel in this indication.

Given BRACELET is important to Pela's value proposition, setting the stage for its upcoming readout will be the primary focus of today's call.

As we look ahead to BRACELET-1 upcoming readout and beyond, we believe we are well positioned for growth with a pipeline that includes two core pillars, namely our HR-positive/HER2-negative breast cancer and pancreatic cancer programs.

Both of these programs represent meaningful registration opportunities supported by compelling proof-of-concept clinical data and FDA Fast Track designations. We expect to have additional guidance on the optimal registration-enabling pathway for these programs later this year, highlighting just how excited these times are for Oncolytics.

With that, I'll now pass the call off to Tom..

Thanks, Matt. Before previewing BRACELET’s upcoming readout, let me first briefly recap our HR-positive/HER2-negative breast cancer programs current clinical data set to provide context for the trial's goals.

I'll start with an overview of IND.213, which was a randomized Phase 2 trial that evaluated Pela combined with Paclitaxel versus Paclitaxel alone.

As Matt mentioned, the trial produced statistically significant data that showed a near doubling of median overall survival in HR-positive/HER2-negative metastatic breast cancer patients in the combination therapy group.

These results supported a subsequent Fast Track designation from the FDA as well as a special protocol assessment agreement indicating that IND.213 was a sufficient foundation to allow advancement to a pivotal licensure-enabling study.

Additional data supporting our HR-positive/HER2-negative breast cancer program include Phase 1 results demonstrating Pela's single agent activity in this syndication as well as results of AWARE-1 a window-of-opportunity study that evaluated Pela-based treatment combinations in early-stage breast cancer patients.

AWARE-1 successfully met its primary endpoint. In addition, AWARE-1 demonstrated Pela's immunologic mechanism of action including its ability to remodel the tumor microenvironment in ways that are associated with improved patient prognosis such as increased infiltration of T cells into the tumor and improvement in the risk of recurrent score.

With these prior results, providing a robust foundational data set for our HR-positive/HER2-negative breast cancer program, the goals of BRACELET-1 are to substantiate the positive results of IND.213 and inform the design of a licensure-enabling study.

To accomplish these goals, we and our collaborators at Pfizer and Merck KGaA, designed BRACELET to enroll 48 patients randomized across three cohorts, a control arm, consisting of standard of care Paclitaxel monotherapy, an arm evaluating Paclitaxel combined with Pela and a third arm in which the checkpoint inhibitor of avelumab was added to Paclitaxel plus Pela.

The first two arms mirror, the IND.213 study groups, while the third arm was included to evaluate whether the additional of avelumab to Paclitaxel plus Pela provides additional benefit. Note that avelumab is an anti-PD-L1 antibody that was co-owned by Pfizer and Merck KGaA when we designed the study. However, today it is solely owned by Merck KGaA.

Note that BRACELET-1 is not powered to demonstrate statistically significant differences between the treatment groups. Therefore, a successful BRACELET-1 result would be a demonstration that one or both of the Pela containing arms numerically outperform the Paclitaxel monotherapy group.

The key endpoints that we are monitoring in the trial include overall response rate and progression-free survival. Another key endpoint is overall survival. However, these survival results need more time to mature before they come into focus.

Next, I would like to lay out the sequence of events that will take place around the BRACELET-1 announcement, all of which will be guided by ASCO’s embargo policy. On May 25 at 5:00 p.m. Eastern Time, the BRACELET-1 abstract will be published on the ASCO website, which will allow us to put out a press release detailing the contents of the abstract.

So, please keep a lookout for that press release with the most up to date information. On Saturday June 3, BRACELET-1’s oral presentation will be delivered by Dr. Amy Clark during one of ASCO's Clinical Science Symposium.

Following this presentation, we plan to host the Key Opinion Leader Webinar on Monday, June 5 at 8:00 AM Eastern Time, to provide expert perspective on the results and what they mean for our HR-positive/HER2-negative breast cancer program’s next steps.

Those interested in joining can find the webinar's registration link on the Events and Presentation section of our website. In addition to the oral presentation on BRACELET, the ASCO Conference will include a poster on preclinical studies evaluating Pela’s potential [indiscernible] technology for CAR T-cell therapy in solid tumors.

These studies were conducted in collaboration with Dr. Richard Vile's group at the Mayo Clinic and followed the publication of a paper on this topic in Science Translational Medicine last year.

As a reminder, data from the Science Translational Medicine paper showed Pela synergistically enhancing the efficacy of CAR T cells leading to cures in murine solid tumor models. This was an exciting finding.

To date CAR T cells have been unable to effectively treat solid tumors despite the fact that they have revolutionized the treatment of blood-based cancers where long-term patient cures have been achieved.

Mechanistic analyses linked the promising results reported in Science Translational Medicine to Pela's ability to overcome the three key challenges that limit the activity of CAR T cells against solid tumors, namely four cell perseverance, immunosuppressive tumor microenvironments, and antigen escape.

With solid tumors representing the vast majority of new cancers, these data suggest Pela may have the potential to substantially expand the addressable population for CAR T cell therapies. Collaborative studies to build on these results are ongoing and we look forward to sharing additional data at ASCO in the coming weeks.

Lastly, before handing it off to Andrew, I'll speak briefly about our Phase 1/2 GOBLET trial. This trial evaluates treatment combinations including Pela plus Roche's atezolizumab and gastrointestinal cancers.

We continue to make encouraging progress in GOBLET with updates from its advanced anal and metastatic colorectal cancer cohorts expected in the second half of the year. In addition, we continue to advance towards key milestones in the trials pancreatic cancer cohort, which forms a foundation of our pipeline's second core pillar.

Updated data from this cohort as well as guidance on the program's path towards registration are also expected in the second half of the year. With that, Andrew will now speak about our business development efforts.

Andrew?.

Thanks Tom. Let me start by reiterating our enthusiasm for Pela's core licensing value proposition, which stems from our two substantially de-risk registration opportunities in breast and pancreatic cancer.

By 2028, the addressable markets for drug treatable HR-positive HER2-negative breast and first-line pancreatic cancer are expected to reach approximately 300 and 135,000 patients respectively across the U.S., major European countries and Japan.

Moreover, data from the IND-213 and GOBLET trial provides clinical proof of concept and demonstrate Pela's potential to substantially improve the treatment paradigm in these indications.

With clinical data de-risking our efforts in large markets with clear unmet needs for improved treatments, we have been gardening healthy interest in our pursuit of a single licensing deal for our breast and pancreatic cancer programs.

While I can't speak to the specifics of ongoing BD conversations at this time, there are a couple of points that I can make now. First, feedback from our ongoing conversations have indicated that BRACELET-1's readout in a few weeks will hopefully kick-off a new phase in our BD process.

Given the potential for BRACELET-1 to provide a second randomized data set demonstrating the ability of Pela Paclitaxel combination to outperform Paclitaxel alone, this feedback isn't surprising. Second, I'll note that even in the event of a successful BRACELET-1 outcome we don't expect to hastily finalize or announce any deal.

If successful, we have a breast cancer program supported by two randomized data sets, a special protocol assessment agreement indicating one of two necessary pivotal studies is complete and a fast track designation. This would put us in an enviable position, any negotiation particularly when paired with a pancreatic cancer program.

Given all this, we plan to continue advancing our BD activities with a disciplined methodical approach that seeks to drive competition among multiple parties.

Our ongoing past collaborative trials have allowed us to establish formal relationships with many of the leading players in the space, including Pfizer, Roche, Merck Serono, Bristol-Myers Squibb and Insight, which we believe leaves us well positioned as we seek the best deal possible for our shareholders.

To conclude my section of the call, I'll speak briefly about our preclinical CAR T program. Building off Tom's earlier remarks, having been heartened by the positive data from the work we've done with Dr.

Vile in the Mayo Clinic, we are advancing research collaborations of biotech companies interested in validating or recapitulating the results from the Science Translational Medicine publication.

One of these companies has already produced results with Pela in combination with their own CAR T constructs that are in-line with what was seen previously in Dr. Vile's work. That company is now repeating those results to ensure their accuracy and we look forward to reviewing them with our research partner in the second half of the year.

Recapitulating the Science Translational Medicine results is an important step for our collaborator because unlike other agents, a class effect cannot be assumed that CAR T cells since they behave according to their specific genetic makeup. We look forward to providing more information on CAR T work with Mayo at the upcoming ASCO meeting.

With that, I'll pass the call off to Kirk for a review of quarterly financials.

Kirk?.

Thanks Andrew. I'm pleased to report that Oncolytics remains well financed through BRACELET-1's readout this quarter, as well as past the important regulatory updates from our breast and pancreatic cancer programs expected in the second half.

As of March 31, 2023 we had $29.7 million in cash, cash equivalents and marketable securities providing us with an anticipated runway into 2024. This compares to $32.1 million as of December 31, 2022. General and administrative expenses for the first quarter of 2023 were $3.2 million compared to $2.6 million for the same period last year.

Now, this increase was primarily due to increase Investor Relations activities partly offset by lower share-based compensation expenses.

Research and development expenses for the first quarter of 2023 were $3.5 million compared to $3.7 million for the same period last year, this decrease was primarily due to lower BRACELET-1 study costs and share-based compensation expenses, partly offset by increased manufacturing expenses associated with a process development production run and higher personnel related expenses.

The net loss for the first quarter of 2023 was $6.4 million compared to $6.8 million in the first quarter of 2022. This equated to a net loss of $0.10 per share for the first quarter of 2023 and $0.12 per share for the first quarter of 2022. So this completes my financial review and brings us to Matt's closing remarks.

Matt?.

Thanks Kirk. Before moving on to the Q&A session, I'd like to close with a brief recap of all the exciting milestones we expect to achieve between now and the end of the year.

The first of these milestones will become later this month when we announced randomized Phase 2 data from BRACELET-1 in an oral presentation at ASCO, which again is a randomized trial that represents Pela's last major step on the path to a registrational study in HR-positive HER2-negative breast cancer.

Also at ASCO, we anticipate reporting additional pre-clinical data on the combination of Pela and CAR T cell and solid tumors.

In the second half of the year, we expect to provide update data from our first line pancreatic cancer program and additional guidance on the registrational pathway for this and our other core program in HR-positive HER2-negative breast cancer.

As a reminder, our special protocol assessment agreement indicates that we've already completed one of two pivotal studies needed for approval in HR-positive HER2-negative breast cancer.

While in pancreatic cancer we envision a randomized Phase 2b/3 trial with an adaptive design that would allow us to move seamlessly from a Phase 2b interim analysis to a larger Phase 3 portion that could support a regulatory filing.

Both of these programs are supported by FDA fast track designations, which should aid in our regulatory interactions as we work to confirm the optimal design for our next trials.

Solidifying these designs will further de-risk our programs and expedite our entry into a registration environment with shots on goal and two indications with a large commercial opportunities and long-standing unmet needs.

Beyond our core programs we will continue to follow the blueprints I laid out on our last earnings calls to take full advantage of Pela's platform potential.

While maintaining focus on our effort and breast and pancreatic cancer this blueprint has leveraged collaborations with leading players in industry and academia to advance Pela in additional high value indications such as anal and colorectal cancer, and [indiscernible] enabling technology for CAR T cell therapy in solid tumors.

By sticking to this blueprint, we've been able to maintain a capital efficient approach while further enhancing Pela's value proposition. Finally, we expect to provide updates on GOBLET's cohorts evaluating Pela and atezolizumab combinations in anal and metastatic colorectal cancer in the second half of the year.

As we work towards our upcoming milestones we are fortunate to have the support of world-class collaborators, talented employees, dedicated investigators and of course all of our investors.

Each of these individuals, as well as our clinical trial participants have been instrumental to Pela's development and the progress we have made towards our mission of improving the lives of patients with cancer. I would like to express my gratitude for all their contributions, and we'll now open up the call for questions.

Operator?.

Thank you, sir. [Operator Instructions] And your first question will be from John Newman at Canaccord. Please go ahead..

Hi, guys. Good morning. Thank you for taking my question. Just curious if you could give us any color on the potential pivotal design for pelareorep in breast cancer.

I know that there's – there's been some studies run in the past with checkpoint inhibitors with various results, but just kind of curious as to how you may or may not work in a checkpoint in a potential pivotal study? Thanks..

Great question, John. Thanks. And to throw another wrinkle in the works, I'm not sure if you read the news that Pfizer turned back avelumab to Merck KGaA. So avelumab is no longer of much interest to Pfizer at this point. I'll get Andrew to touch on the economics, but if we consider IND-213 [indiscernible].

Hello. We lost you, Matt..

Hello..

Well, we lost you there for a second..

Sorry. So IND-213 was a – we showed an overall doubling survival and HR-positive HER2-negative in a very, very heavily appreciated patient population who'd all had previous exposure to taxanes. BRACELET has paclitaxel to paclitaxel Pela alone and we're in a much earlier patient population who are taxane naïve.

So we're hoping to see differences in PFS, ORR and keep that huge sort of delta that we had seen with overall survival. We would like to see improvement with avelumab, but the reality of it is if we've doubled overall survival, the increased benefit that the additional $200,000 at avelumab would cause – really has to be taken into consideration.

We're going to have to see quite a dramatic improvement beyond that one-year overall survival to rationalize another $200,000.

Andrew, do you want to talk a little bit about what payers have to say?.

Yes..

Where checkpoint inhibitor might come into lifecycle management? And then Tom, I'll get you to talk about what we think is the most probable trial design.

So Andrew, do you want to kick us off?.

Sure. Absolutely. So we actually did some research with European payers to see what they would need to see in terms of a survival benefit to cover the product. And we chose the Europeans because as you know, they're much more stringent with coverage decisions than, than the U.S. So it's kind of a higher – a harder task master.

And the feedback from them was, look, a 3.5 to four- month OS improvement over paclitaxel would probably garner their interest and allow us to discuss contracting and the rest of the coverage process with them. That was for pelareorep plus paclitaxel as the value proposition.

So if you add avelumab and you add another – we haven't decided where we're going to price ours, but let's say for arguments sake that we'll price around where the CDK4/6 would price by then, which would historic price increases would be over 200 grands per year by time of launch.

And looking at the price increases for checkpoints, let's assume it's the same as Matt was kind of alluding too. For avelumab, you're talking about $400,000 charge per patient to treat.

You're going to – I haven't spoken the affairs, but having been a reimbursement consultant I can tell you they are going to tell us, you're probably going to have to find the patients that have a doubling of overall survival. So the cost of the additional [indiscernible] is a rate limiting factor that has to be considered.

If we think we can do – well clinically and therefore commercially with just pelareorep plus paclitaxel. So that's really the, one of the challenges that we have to think about. We always think about lifecycle management. We could always do a separate or smaller trial if we choose to not include the checkpoint.

I'm not saying we aren't, but one thing that could be done is look at that in the lifecycle management to try and find maybe the patients who would have that kind of a response and therefore be able to tell, say, look, for these patients with this profile we think they'll respond and talk to the payers that way.

Matt, anything else from your perspective there?.

No. I think that's fantastic. I really think it becomes a very important figure in lifecycle management. I'm not sure it's as important for what the Phase 3 looks like because we really do want to capitalize on the 213 results and then expand those hopefully with BRACELET into a Phase 3 opportunity.

Tom, did you want to talk a little bit about what a study would likely look like?.

Yes. Sure, Matt. So with the comments of Matt and Andrew in mind, I think the study design will be – will be comparatively straightforward. We would envision a two-arm study with a Paclitaxel control arm and then a Paclitaxel plus pelareorep with or without avelumab investigational arm.

And we would then obviously power it appropriately for an overall survival endpoint and perhaps a PFS endpoint depending on how things play out. But we – but I think the overall design would be pretty straightforward two-arm study..

Thank you, John..

Okay, great. Thank you..

Thank you. Next question will be from Louise Chen at Cantor Fitzgerald. Please go ahead..

Hi. Congratulations on all the progress this quarter, and thanks for taking my question.

So I wanted to make sure I heard you right when you said that BRACELET-1 was not powered for stat sig and if not, what do you want to see to consider this a successful trial or what do you expect to see? And then secondly, can you elaborate more on the CAR T opportunity and what that means for you? And last question I had for you is on your cash runway, what positive inflection points does that bring you through? Thank you..

Thanks Louise.

Tom, do you want to take the first question, Andrew the second, and Kirk the third?.

Sure. Well, the first question was, I'm sorry, say that again please..

Yes. So did I hear you right in that, you did not power BRACELET....

For the powering, yes. Yes. So the BRACELET study is a randomized study. So the patients are randomized between the arms. However, it was not powered to allow a formal statistical comparison.

So what we – what we will look for in that study as a – as criteria for success are numerical differences between the groups in the key – in the primary endpoint, which is objective response rate as well as any other efficacy endpoints.

As we mentioned, we will be reporting the progression-free survival results, but the overall survival results are not mature enough to report at this time. So we will be looking for numerical differences and then obviously we can one can conclude based on the magnitude of those differences.

But keep in mind also that this study is not a standalone study in that it is the first two arms of this study, which are the Paclitaxel versus Paclitaxel plus pelareorep are basically recapitulating the former IND study in which we saw the strong survival benefit.

So this is from an efficacy perspective will largely be a confirmatory study to provide additional confidence and to de-risk the program further..

Opportunity in CAR T, Andrew, do you want to talk a little bit about how we would look at sales and royalty in that particular environment and how across, this could potentially work across platforms?.

Yes. Absolutely. So if you remember from Science Translational Medicine article each of the mice that had these dramatic responses utilized two doses of pelareorep. One that was basically conjugated with the CAR T and administered to the mouse, and then a boost dose afterwards.

So the goal is to open up solid tumors for CAR Ts because they struggle to show any efficacy there. And Kirk, you know, solid tumors are 85% of the market, so it's right now running fallow. But it's about selling CAR Ts in the solid tumors. Two doses of pelareorep are dropped in a bucket for us compared to the potential in breast or pancreatic cancer.

So it's not about selling Pela, it's about selling the $400,000 CAR T and say a liver patient, but for the pela would not be able to be treated with the CAR T.

So the way we see this working is that there would be some kind of an upfront that would be determined by the number of CAR Ts involved, the number of tumor targets involved, then there might be some development regulatory milestones along the way, but the big revenue would be some sort of double digit royalty on the sale of that CAR T in every patient where pelareorep is added for the treatment.

So, it could potentially turn into a nice revenue stream for us that could be applied to any number of our needs. But it is not our core focus. We would advise and provide pelareorep to the CAR T developing and then commercializing the combination. But we don't have any immediate term to get into CAR T business ourselves..

Yes. Then with respect to our cash and cash runway, we reported just under $30 million at the end of the quarter. We anticipate that that provides a runway of at least 12 months. In terms of catalyst and milestones the cash on hand gets us through well clearly the ASCO BRACELET presentation we have CAR T updated ASCO as well.

In addition, the GOBLET study we are targeting to provide efficacy updates on the pancreatic cancer cohort. We're targeting ESMO, but that's to be determined. And the other cohorts, the colorectal and the anal cancer cohort, we do expect to provide interim updates on those on those other cohorts in the second half of the year.

And our runway takes us through those events..

Thank you..

Thank you. Next question will be from Patrick Trucchio at H.C. Wainwright. Please go ahead..

Thanks. Good morning. Just one clarification as it relates to BRACELET-1 and the registration path for HR-positive/HER2-negative metastatic breast cancer.

It sounds like you would need just the one pivotal study to submit for potential approval, though maybe you could elaborate more on that point specifically and potential for the accelerated approval pathway and how this upcoming ASCO data specifically could facilitate this pathway.

And secondly, can you give us an update on the GOBLET program, including the expected next data release in the second half, the timing of this data and what you would be looking for here to give confidence to advance the program to a registrational study? Thank you..

Absolutely. So to start with the GOBLET, we've spoken with AIO and our Principal Investigator, Dirk Arnold. We are starting to see maturity in the pancreatic data. So, we'll be able to present PFS and we likely believe evolving or somewhat mature OS by ESMO GI, which is in Barcelona in October. So, that's really the timeframe that we're working to.

We're also hoping to provide updates on the other three cohorts likely again, within that timeframe of ESMO GI just because it is such a, a great showcase for GI therapies. And we'd have the right audiences, right KOLs. So we think that would be very an opportune timing.

The PEG data we've discussed with stakeholders, the signal was so strong we could have expanded that to an additional 30 patients. But, with a 69% objective response rate really we felt that we had demonstrated a very, very strong signal. And what we wanted to do is move it into a more stringent environment.

So what we're talking with corporate partners like is randomized Phase 2 in the 60 patient range. We're also speaking with cooperative groups that would actually be capable of running a Phase 2b/3 program. So an adaptive design where we would enroll, I think, it's 60 to 80 patients in that Phase 2b program.

And if we're seeing the signal that we want to see, we would just seamlessly move into the Phase 3. This is very attractive because the cooperative groups provide a lot of expertise and cost deferral, but more importantly, they are expeditious. They have a pre-approved protocols with the FDA.

So if we can get through their selection process, it's just a plug and play to get into the Phase 3 environment.

Sorry Patrick, I'm trying to recall, what was the first part of your question?.

Yes, just on the on the registrational pathway for HR-positive/HER2-negative with Pela and with this BRACELET-1 data, just want to clarify that you would only need the one pivotal study going forward for potential submission for – the regulatory submission for approval. I just want to make sure that that is what is possible.

And to the extent that it depends on the ASCO data, how does – just how does that facilitate this accelerated pathway?.

Well, absolutely. That's also another great question. IND.213 showed that doubling of overall survival, we took that to the agency and what they told us is this will provide you with a special protocol assessment.

For anyone who is listening, what that means is we've agreed to a protocol with the agency and they have already, because they have granted that the IND.213 de facto is one of the two required randomized studies. So, we are only one randomized study away.

Now people ask me like, they are like, why would you then go and do BRACELET? And really the question for that was IND.213, we were working under the assumption that this was largely lytic. The result very strongly indicated that lysis was probably occurring, but the mechanism driving this was really a T-cell-mediated response.

So the agency said, listen, you can start that Phase 3, but you're doing so at some tremendous risk. If you don't fully understand mechanisms of action, and if you don't have at least some biomarker planned that measures a T-cell response that would tell you whether or not those patients are responding.

So Pfizer was looking at the end of Phase 2 minutes and the SPA and they agreed, they said, listen one of the things that we can actually look at that we're quite excited about, IND.213 was a very heavily, pre-treated patient population. Just to remind everyone, we saw about a three-week improvement medium PFS.

But in that patient population, everyone had already been exposed to or had failed a taxane. Where BRACELET is a little bit different is it recapitulates what we saw in IND.213, but it does it in the group of women who are taxane-naïve. So, our hypothesis was if patients have a less damaged or a less challenged immune system.

Let's keep in mind standard chemotherapies like taxanes really are detrimental to immune response, especially multiple rounds of it. Our thinking was if we moved to an earlier setting, we could actually, potentially look at whims in areas like ORR and PFS where we were seeing a hint of a signal in appreciated groups.

So, we thought in a pretreated group that would expand that opportunity. Now, if that's actually the case, it's potentially very important in terms of our registration path because a PFS win would get us to a registration program much, much earlier than OS would because obviously you have to wait for that OS to mature.

So what we're hoping is if we see the a positive signal in PFS, we could move to dual endpoints for the registration program that would give us a win that could potentially be as much as 18 months or later..

Perfect. Thank you so much..

Thanks Patrick..

Thank you. [Operator Instructions] And your next question will be from Douglas Miehm at RBC Capital Markets. Please go ahead..

Yes, good morning.

First question, if you were to take the OS data from the IND.213 and apply it to the currently ongoing trial, when would you expect to start to see maturity of OS data in this in BRACELET-1?.

Well, I'll let Tom speak to, the expectations that the last patient put on study was June, 2022. So for PFS the expectation on the control arm is about a six-month medium PFS. So we've got all patients out now 12 months beyond that. So I would say that that's reasonably – we'll have mature PFS for ASCO. OS we're starting to see the events now.

As I said, the study started 2020 and we've got patients who are on study now for three or more years. Last patient was more than a year ago, you would anticipate survival here to be about a year. So we're anticipating we should have a pretty good idea by San Antonio.

What we're looking for though, Doug is 80% of the event, so it might be an early 2024 event..

Okay, perfect.

And then just remind me if you're allowed to, were patients – the 48 patients equally divided between the three arms, so 16 in each?.

No, it was 15 on the Paclitaxel, 15 on Pac Pela because we had already had that. The agency wanted to see a three patient safety run in. So, the Pac Pela avelumab had a three patient run in plus 15, so they have 18..

Perfect. Okay, thank you..

You're welcome..

Thank you. And at this time, gentlemen, it appears we have no further questions. Please proceed..

Thank you operator. And we wanted to thank everybody who participated this morning. We are just a few weeks away for being able to disclose what happened on BRACELET. We're obviously very excited. And we would encourage anyone who can to participate in our KOL Call the morning of June 5.

With that, I'll say thanks again and have a lovely morning everyone..

Thank you, sir. Ladies and gentlemen, this does indeed conclude your conference call for today. Once again, thank you for attending. At this time, we ask that you to please disconnect your lines..