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Edited Transcript of SESN earnings conference call or presentation 13-May-19 12:00pm GMT

Q1 2019 Sesen Bio Inc Earnings Call

Cambridge Jun 22, 2019 (Thomson StreetEvents) -- Edited Transcript of Sesen Bio Inc earnings conference call or presentation Monday, May 13, 2019 at 12:00:00pm GMT

TEXT version of Transcript

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Corporate Participants

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* Erin Clark

Sesen Bio, Inc. - Executive Director, Strategic Planning & IR

* Thomas R. Cannell

Sesen Bio, Inc. - President, CEO & Director

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Conference Call Participants

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* Christopher Lawrence Howerton

Jefferies LLC, Research Division - Equity Analyst

* Yale Jen

Laidlaw & Company (UK) Ltd., Research Division - MD of Healthcare Research & Senior Biotechnology Analyst

* John Lawrence Newman

Canaccord Genuity Limited, Research Division - Principal & Senior Healthcare Analyst

* Swayampakula Ramakanth

H.C. Wainwright & Co, LLC, Research Division - MD of Equity Research & Senior Healthcare Analyst

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Presentation

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Operator [1]

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Good day, ladies and gentlemen, and welcome to the Sesen Bio 1Q 2019 Business Update. (Operator Instructions) As a reminder, this conference call may be recorded.

I would now like to introduce your host for today's conference, Executive Director, Strategic Planning and Investor Relations, Erin Clark. You may begin.

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Erin Clark, Sesen Bio, Inc. - Executive Director, Strategic Planning & IR [2]

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Thank you, and good morning. Welcome to today's conference call to discuss our updated preliminary Phase III clinical data and upcoming milestones. On the call with me today are Dr. Thomas Cannell, President and CEO; Dr. Dennis Kim, Chief Medical Officer; Richard Fitzgerald, Chief Financial Officer; and Dr. Chad Myskiw, Strategic Planning and CMC.

Earlier this morning, we issued a press release outlining our first quarter 2019 financial results. The press release and the slides to which we will refer are available on the Investors section of the company's website at sesenbio.com.

Today's discussion will include forward-looking statements related to the company's current plans and expectations, which are subject to risks and uncertainties. Actual results may differ materially due to various factors, including those described in Sesen Bio's most recent annual report on Form 10-K and other SEC filings. These statements represent Sesen Bio's views as of this call and should not be relied upon as of any future date. Sesen Bio undertakes no obligation to publicly update these forward-looking statements.

With that, I'll turn it to -- turn the call over to Tom.

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Thomas R. Cannell, Sesen Bio, Inc. - President, CEO & Director [3]

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Thanks, Erin, and thanks, everyone, for joining us this morning. Today, I will share updated data for all of our Phase III study endpoints based on a March 1 data cut, along with the regulatory and commercial update.

But before we get into the agenda, please turn to Slide 3, our patient journey slide. The patient journey is our true north as a company, so we always start with this slide in all internal and external meetings. Based on patient surveys, we know that the experience of those with bladder cancer is one of the worst when compared to other cancers, and nothing is more damaging to the patient's quality of life than full bladder removal, known as radical cystectomy.

In the past, BCG has been the only option for patients with high-risk, non-muscle invasive bladder cancer prior to the doctor recommending radical cystectomy. And unfortunately, we are again seeing shortages of BCG in the United States. In January, the sole supplier of BCG in the U.S. announced another BCG shortage and has since said it expect the shortage to last least through 2019. As a result, many prominent groups, such as AUA and BCAN, are advocating for the FDA to find solutions. This certainly adds to our sense of urgency in bringing Vicinium to market quickly to help save and improve the lives of these patients.

Now please turn to Slide 4, our agenda slide. There are really 3 key parts to the Sesen Bio story that I want to provide an update on today: first, we believe our updated Phase III clinical data further demonstrate the compelling efficacy and safety profile of Vicinium; second, we are confident in the strong regulatory and commercial probability of success; and finally, we have a simple and reliable manufacturing process and supply chain that we believe minimizes the chance of product shortages and will result in a lower cost of goods.

Turning to Slide 5. We filed our Form 10-Q on Friday, May 10, and we finished the quarter with a strong balance sheet and cash runway into 2020. In addition, we have 2 face-to-face meetings with the FDA in the next 30 days: a Type C meeting on May 20 and a Type B pre-BLA meeting on June 6. We have submitted the briefing books for both meetings based on the March 1 data cut, and we will walk through a subset of those data today.

I'd like to point out that the Type B pre-BLA meeting on June 6 will be the sixth Type B meeting with the FDA since our end of Phase I meeting for Vicinium, and that series of high-quality interactions has allowed us to fully align with FDA guidance.

Please turn to Slide 6, which in my mind remains one of our most important slides. In February last year, the FDA issued updated guidance on the development of therapies for non-muscle invasive bladder cancer. Because of our long-term partnership with the agency, we were able to anticipate this guidance and structure our clinical program and draft BLA accordingly. As you can see on the slide, we're aligned with all the key elements of the 2018 FDA guidance. And this alignment, along with our compelling clinical data set, is the reason we believe we have a strong regulatory probability of success.

Turning to Slide 7, based on the March 1 data cut, we are now able to present all of the primary and secondary endpoints that you see here to demonstrate the favorable benefit-risk profile of Vicinium, which the 2018 FDA guidance takes as the basis for product approval.

Please turn to Slide 8, where we review data for one of our primary endpoints, complete response rate for carcinoma in situ patients. 3 things are very meaningful: first, the significant and reproducible complete response rates between Phase II and Phase III, giving us 2 well-matched trials for BLA submission; second, we believe the lower bound of the 95% confidence interval rules out a clinically unimportant complete response rate per FDA guidance, which is illustrated by the content span shown on the graph; third, our Phase III eligibility criteria required patients to have received at least 2 courses or 7 installations of BCG. Many of the patients received significantly more than 2 courses, and the average patient in Phase III received 15 installations of BCG before entering our trial.

As you can see on the slide, patients who received 7 to 10 installations of BCG went on to have a 25% complete response rate at 12 months, which we believe demonstrates a greater level of efficacy in patients who receive less BCG. This is especially important in light of the BCG shortage, where organizations such as the AUA have issued updated guidelines recommending reduced doses of BCG in some cases and recommending that patients are switched more quickly to other therapeutic options.

Please turn to Slide 9, which shows data we believe will be significant in clinical practice. In Phase II, we utilized bladder mapping, which was not done in Phase III and is not required in the FDA guidance. What we learned in Phase II was that in addition to the 40% complete response at 3 months, there were roughly another 40% of patients who had a partial response.

We know from talking to key opinion leaders and our investigators who have treated these patients for many years that in clinical practice, a partial response can be a very positive outcome given the difficulty of treating an aggressive field change disease such as carcinoma in situ. A partial response may give physicians and patients additional options as they move forward in their journey.

Slide 10 shows the other primary endpoint in our Phase III trial duration of response in carcinoma in situ patients who had a complete response at 3 months. As you can see on the left side of the slide, based on the Kaplan-Meier estimate for patients who achieved a complete response at 3 months, 54% had a duration of response of 9 months or longer.

It is important to note that duration of response measurement start at the 90-day point after the patient has been confirmed with the complete response. So in other words, you can see when looking at the graph that if you have a complete response at 3 months, you have roughly a 50% probability of maintaining complete response for at least 12 months after you started on therapy.

On the right side of the slide for complete transparency, we show you the swim lanes for all responders at 3 months. Again, if you look at patients who had a complete response at 9 months, the vast majority are still going or have made it successfully to 24 months.

The FDA guidance says that complete response rate should be considered in the context of the duration of response. Therefore, we believe this is very -- a very important slide as it demonstrates Vicinium's strong and durable antitumor effect in carcinoma in situ patients.

Slide 11 shows data for Cohort 3 from our Phase III trial, which is high-risk, non-muscle invasive bladder cancer patients with papillary disease. By definition, these patients have no visible evidence of disease at day 0 of the trial because the tumor has been resected. And therefore, time-to-disease recurrence is the appropriate endpoint to evaluate response.

As you can see, after starting treatment with Vicinium, high-risk papillary patients have a 50% probability of remaining disease-free for at least a year and a 36% chance remaining disease-free for at least 24 months. Another way to think about it is that these are high-risk patients with papillary disease who have failed on at least 2 courses of BCG, and their only option is radical cystectomy.

In the future, their doctor may be able to present another option and explain that the average patient with papillary disease who receives Vicinium is projected to be disease-free for 402 days or approximately 13 months and that over 1/3 of patients are disease-free for over 2 years. Finally, the doctor can explain to the patient that the longer they are disease-free, the better their prognosis becomes.

We believe those efficacy messages in combination with the favorable tolerability profile will lead many doctors and patients to choose Vicinium rather than radical cystectomy.

Slide 12 shows our time to cystectomy data across all patients treated with Vicinium, and the strong data I will show you is a function of the efficacy and durability that I just reviewed. Although this is a secondary endpoint from a regulatory perspective, we believe it is arguably the most important endpoint for physicians, patients and payers.

Using our updated data as of March 1, the average patient will remain cystectomy-free for 854 days or approximately 28 months based on Kaplan-Meier. Since most of our patients are now evaluable at 24 months, this means that a median will likely not be reached as the majority of patients are estimated to be cystectomy-free at the end of the trial.

You can see on this slide, the FDA provides guidance on time to cystectomy, which states that the goal of therapy in patients with BCG-unresponsive non-muscle invasive bladder cancer is to avoid cystectomy. When we look at these data for responders of Vicinium versus nonresponders, we see that responders are approximately 15x more likely than nonresponders to remain cystectomy-free at 2.5 years. We know the responder versus nonresponder ratio is very important to the FDA. Therefore, although time to cystectomy can have confounding factors, we feel these data are very strong and compelling from a regulatory and a commercial perspective.

On Slide 13, you'll see data for an additional secondary endpoint, progression-free survival for all patient cohorts. At 2 years, over 85% of patients treated with Vicinium remain progression-free based on the Kaplan-Meier estimate.

Turning to Slide 14, you see data for 2 additional secondary endpoints: event-free survival and overall survival. Event-free survival measures events, which consist of disease recurrence, progression or death. At 12 months, approximately 30% of patients were event-free. Looking at overall survival, an estimated 91% of patients treated with Vicinium have an overall survival of greater than 2.5 years based on the Kaplan-Meier estimate. Although it is still early for the survival endpoints, we are certainly pleased with the data we have so far, which further support the durability of treatment with Vicinium.

Please turn to Slide 15, where we see the safety and tolerability data of our Phase III trial. The majority of adverse events were considered mild to moderate and were consistent with the patient population and frequent use of catheterization. In addition, there was a low rate of discontinuation and treatment-related adverse events.

We believe that favorable safety and tolerability data are due to Vicinium's unique dual mechanism of action which, unlike other available therapies, selectively targets cancer cells while leaving most healthy tissue alone. Because of this, we believe the safety profile of Vicinium is favorable relative to BCG, VALSTAR and checkpoint inhibitors.

On Slide 16, we see the same favorable safety and tolerability profile in both our Phase II and Phase III clinical trials. We know that having 2 well-matched clinical data sets is a significant advantage for -- from a regulatory perspective. Therefore, we believe the fact that we are able to demonstrate favorable and consistent safety and efficacy data across Phase II and Phase III puts us in a strong position for BLA submission.

Please turn to Slide 17. We just covered a lot of new and exciting data, and this slide helps to summarize the key definitions and findings. Overall, we believe that the totality of Phase III data suggest a strong regulatory and commercial probability of success. We look forward to reviewing these data with the FDA in greater depth at our pre-BLA meeting on June 6.

Now I'd like to shift to a discussion of the commercial opportunity for Vicinium. We continue to conduct market research among patients, physicians and payers, which builds on the foundation for our overall go-to-market strategy. However, as we said on the last call, any significant commercial investment will be stage gated until after BLA submission.

So please turn to Slide 19, which outlines our commercial strategy. It is our hypothesis that the commercial opportunity is driven by unique situation, where there's a virtuous cycle driving demand across all 3 key customer segments: patients and their caregivers and families; physicians and ancillary health care professionals; and payers, both private and public.

While the drivers of behavior are different for each segment, we see potential for action and advocacy from all of these customers in support of Vicinium. It's unusual for oncology products to launch with advocacy from all key customer segments, and we think this dynamic will help to drive rapid uptake and strong growth of Vicinium after approval and launch.

Slide 20 is an updated version of a slide we showed on our March 4 call. We continue to build on our understanding of the addressable market in the U.S. and have learned the market opportunity is really a function of 2 things: one, there is a huge unmet need in a highly prevalent cancer; and two, Vicinium is a product with potential for meaningful customer value.

It's important to note that the opportunity outlined in this slide represents only on-label use relative to our anticipated indication in-label. As is often the case, there may also be significant spillover opportunity, which we treat as an upside sensitivity and is not in our models at this time.

Please turn to Slide 21. We have recently finished our second round of payer research, and we have now spoken to over 20 payers, both commercial and Medicare. We have been pleasantly surprised by the most common pricing benchmarks and the limited restrictions to reimbursement that seem likely. We believe there is the potential for significant reimbursement and advocacy by payers for the appropriate use of Vicinium.

Slide 22 shows the insights we have gained as it relates to markets outside the United States. While we believe the U.S. represents a substantial opportunity, we estimate that the opportunity for Vicinium outside the U.S. is even larger. As you can see on the slide, regions such as Europe and Asia, including Japan, represent sizable market opportunities for Vicinium.

As I said on the last call, it is our strategy to sign 6 to 10 regional partnerships that cover 60 to 80 countries. That being said, we know the OUS partnering process can take a minimum of 6 to 12 months. So realistically, we will probably not be providing specifics on OUS partnerships until early 2020.

I'm very pleased with the progress made in our commercial planning to date. As we get closer to BLA submission and approval, I'll be sharing more details. But I'm confident in the commercial opportunity and our ability to realize that opportunity if Vicinium is approved.

Please turn to Slide 24. You can see an illustrative example of our single-step supply chain. Vicinium is a fusion protein with a straightforward and elegant microbial expression system that has the potential to create a simple and reliable manufacturing and supply chain and reduce the cost of goods.

Turning to Slide 25. As we announced in our press release this morning, we have recently completed the full-scale GMP manufacturing run at our partner FUJIFILM's facility as part of the ongoing tech transfer process, with encouraging preliminary results. We remain confident in our overall analytical comparability plan, the components of which are outlined on the slide. And this will be the primary topic of discussion during the FDA Type C CMC meeting on May 20.

Finally, please turn to Slide 26. As a summary of the 3 key elements of our story, we are very encouraged by the most recent analysis of our 12 month Phase III data and look forward to continuing to work closely with the FDA to expeditiously bring a product to market that has the potential to save and improve the lives of patients with non-muscle invasive bladder cancer.

Let me conclude today by saying we are very excited about the opportunities we have to fulfill our mission while providing meaningful value for shareholders. I would like to thank our courageous patients and their families as well as our dedicated Sesen employees who have all helped us advance to this stage.

With that, we'll open the line to take your questions. Operator?

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Questions and Answers

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Operator [1]

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(Operator Instructions) And our first question comes from John Newman with Canaccord.

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John Lawrence Newman, Canaccord Genuity Limited, Research Division - Principal & Senior Healthcare Analyst [2]

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So Tom, I was just curious if you could talk a little bit about your data, time to cystectomy. And what will be the proper way to think about that in the context of VALSTAR? And just also in general, I feel that the conversations that I have with investors are still kind of working to understand how your efficacy data compared to VALSTAR overall? Just curious if you could walk us through that?

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Thomas R. Cannell, Sesen Bio, Inc. - President, CEO & Director [3]

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Yes, great. Thanks, John. So it sounds like there's 2 questions. First, just to talk a little more about the relevance of the cystectomy data and then second of all, just to give you kind of a side by side of Vicinium relative to VALSTAR.

The -- as I mentioned, the time to cystectomy data, the FDA in their February 2018 guidance says that it needs to be taken in the context of some physician and patient variability. For example, we know that 50% of patients who are told by their doctor they need radical cystectomy still decline the surgery. So it's an analysis that needs to be carefully measured.

What we learned from the ADCOM meeting in the late '90s for VALSTAR as well as the 2015 ADCOM for non-muscle invasive bladder cancer, that the FDA puts a lot of emphasis on the difference between responders and nonresponders in terms of time to cystectomy. The reason for that is, obviously, for responders, you're delighted to be able to avoid cystectomy because the product is working. For nonresponders, they may have a chance to try other therapies. But if not, you would like to see them move expeditiously to radical cystectomy.

So it's compelling that our data now show an average of 28 months delay in time to cystectomy, and that will be a very relevant piece of information for physicians, patients and probably especially for payers. But equally important is the 15-fold differential between responders and nonresponders. And I think that, from a regulatory perspective, that's going to be a very important part of the approval process and hence give us additional efficacy data.

So that's the cystectomy. We're very excited about it, and we'll continue to be doing -- we're really looking forward to the next round of market research where we can show the customers this new data and get their reaction.

Then let's just step back and just do a side by side on VALSTAR versus Vicinium. And let me just start -- as I'm sure you know, it's very difficult to make these comparisons. You've got VALSTAR, which was approved -- which did their studies in the 1990s and was subject to completely different set of rules from the FDA. And then you're trying to compare it to a product that's perfectly aligned with current FDA guidance. So everything I say has to be taken with a grain of salt because it is so hard to compare clinical trials that are -- that span decades.

But let's just start with probably, I think, the biggest difference, which is just the safety profile. So VALSTAR is a cytotoxic chemotherapy agent. It equally attacks healthy and tumor cells. And you've got to remember that it is -- this is for BCG-unresponsive patients. So the patients have just had many installations of BCG, which causes an inflammatory granulomatous reaction. And then it is so difficult to use a product like VALSTAR because it's also going to cause a very inflammatory reaction.

We know looking at their data that bladder spasm and bladder pain, which is excruciating for patients, we see over 30% in their clinical trials and then in the Vicinium trials, less than 5%. So when we talk to our investigators, they really feel like there's a significant difference in the safety and tolerability of Vicinium versus VALSTAR, and that's probably the biggest difference between the 2 products.

Then you turn to efficacy. And again, we have to look at this very carefully. So VALSTAR -- their only endpoint in their Phase III trial that's reported in their label is their complete response at 6 months. And again, we know that they report 18%. We report Vicinium at 28%. And as you know, using the Clopper-Pearson confidence interval, we now exclude the VALSTAR complete response rate at 18%. So we think we have a statistically significant difference in efficacy at 6 months.

Then when you look at the duration of response, remember, in the current guidance, the FDA says the duration response is measured at 3 months after the complete response rate. But VALSTAR didn't have a 3-month complete response. So VALSTAR looks at patients who have a complete response at 6 months in their label to calculate their 13.5-month duration of response.

So we have to go back, and as you'll see in one of the backups, if we do an apples-to-apples comparison and look at what is the duration of response for Vicinium or patients that have had the complete response for 6 months, it's 20.8. So I would say complete response, you compare our 28 to their 18. Duration of response, you compare our 20.8 to their 13.5.

Then what that takes you to is their label. They have a very limited label, it's only when radical cystectomy is contraindicated and only for carcinoma in situ patients. We expect to have a full label, and we expect (inaudible) be positioned in front of radical cystectomy. Because of their limited label, payers are very reluctant to reimburse for off-label use. So payers require prior authorizations proving that the patient is medically contraindicated for radical cystectomy, and that's a big barrier for physician prescribing a VALSTAR. We, as I mentioned, expect to have minimal reimbursement challenges when it comes to things like step addeds and prior auths.

So that's kind of the big picture. It's hard to compare the 2. But again, we feel like there's a meaningful difference in mechanism of action and safety and efficacy and in the label that comes from that. Does that make sense, John?

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John Lawrence Newman, Canaccord Genuity Limited, Research Division - Principal & Senior Healthcare Analyst [4]

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Yes, it does.

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Operator [5]

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And our next question comes from Yale Jen with Laidlaw & Company.

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Yale Jen, Laidlaw & Company (UK) Ltd., Research Division - MD of Healthcare Research & Senior Biotechnology Analyst [6]

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Congrats on the data. Just trying to follow up a little bit actually on the pricing side that may be slightly early than you may have revealed the details. But you have suggested before that using a value price -- value-based pricing may be -- become more attractive to the market. First of all, is that still the thoughts here? And secondly, any additional color you can add to that?

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Thomas R. Cannell, Sesen Bio, Inc. - President, CEO & Director [7]

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Yes. Thanks, Yale. Thanks, that's a great question. So as we show on Slide 21, we're getting a better understanding of the most common price benchmarks. As you know -- and as I mentioned before, we won't guide on pricing until shortly after approval of the product. So it's a while until we'll guide on price. But at this point, we can provide the price benchmarks we're receiving from payers. We see that in talking to CMS about Medicare reimbursement as well as the commercial plans, they're very interested in value-based contracts.

And so that will be our strategy. We'll pick a price benchmark, and then we'll share risk around that. In other words, if the product works a little better than expected, it'll -- the price will be even a little bit above the benchmarks. And if the product doesn't work quite as well, it would come down a little from that.

As you know, measurability is always the hardest part of executing these value-based contracts. A lot of people talk about them, a very few can execute them. But we are fortunate in this case because most bladder cancer costs are in-patient and relatively easy to track and measure. So we expect to have -- to set the price shortly after approval and then to negotiate value-based contracts with both public and private payers.

Did you have a follow-up question, Yale?

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Yale Jen, Laidlaw & Company (UK) Ltd., Research Division - MD of Healthcare Research & Senior Biotechnology Analyst [8]

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Yes, I do. First, I appreciate the colors. And the -- my follow-up question here is that for the duration of response, you have get -- at this point, how do you see that commercially competing to all other options -- treatment options there?

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Thomas R. Cannell, Sesen Bio, Inc. - President, CEO & Director [9]

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Yes. Thank you. Well, as I mentioned, we really feel like the durability has become a very strong part of our story. And we know it's a very important part of the -- it's a very important part of the FDA guidance. There's -- I put an extra backup slide [in] Slide 32, just for everyone's reference. And just for everyone on the call, we only went through about half the slides. We just tried to tell a clear, simple, straightforward story, but we put a lot of backup slides for your reference down the road as you're doing diligence or looking at the story.

Slide 32 is very interesting. Again, I'll just have you look at the left-hand side of the slide. If you have a complete response at 9 months, you have a 94% chance of having a complete response at the next check-in in 3 months at the 12-month point. So you can see that in terms of what are the odds of having a complete response at 12 months, they go up significantly the longer you have a complete response.

The other way we cut the data on the right-hand side was what are your odds of having a complete response for an additional 12 months. So again, if you make it to the 12-month data point, you have a 69% chance of making it for another 12 months.

And one thing that we learned from investigators and key opinion leaders is that the efficacy story is contextual. So the patient walks in and talks to the doctor, they've failed on at least 2 courses of BCG. The doctor says your only option is radical cystectomy. And hopefully, in the future, they'll say, "Or you can try Vicinium." And they'll say, "There's a 40% chance you have a complete response." That means you have a field change disease, carcinoma in situ. And there's a 40% chance you'll be completely disease-free in 3 months.

There's also a 40% chance you have a partial response, which means we've stopped the progression of the tumor or even if it's shrinking, and that'll give us a whole lot of options. So the patient is thinking right now, "Do I have radical cystectomy, or do I try this product for 3 months?" Then again, for those patients that have a complete response at 3 months, now your prognosis and the odds of maintaining that complete response have gone up significantly.

And each time the patient comes in every 3 months for their check-in, the doctor -- they're having a more confident discussion about the patients' future, their prognosis and their ability to avoid radical cystectomy. So we think duration of response in the commercial arena is actually more important than the initial complete response rate.

And you have a follow-up, Yale?

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Yale Jen, Laidlaw & Company (UK) Ltd., Research Division - MD of Healthcare Research & Senior Biotechnology Analyst [10]

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I'm fine now. That's very, very helpful. I really appreciate that colors in terms of the patient dynamics there.

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Operator [11]

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And our next question comes from Chris Howerton with Jefferies.

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Christopher Lawrence Howerton, Jefferies LLC, Research Division - Equity Analyst [12]

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Congrats on the updates here, Tom. Appreciate all the added information. And quite the deck you put together, it's very comprehensive. I think for me, just a couple questions primarily related to the upcoming FDA meetings. So I think maybe hopefully start with the easier one, for the CMC meeting which I think is here in May. What are you hoping to accomplish there? And what are maybe outstanding issues that you hope to get alignment with on the FDA?

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Thomas R. Cannell, Sesen Bio, Inc. - President, CEO & Director [13]

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Yes. Thanks, Chris. We're looking forward to it, 2 FDA meetings in the next 4 weeks. It's a very exciting time for us. They're both face-to-face meetings down in Silver Spring. The Type C CMC meeting will focus on our analytical comparability plan. As we've mentioned, we did tech transfer -- we made our supply for clinical trials in our Winnipeg manufacturing site, and our commercial supply will be manufactured out of Fuji. So we're going through the tech transfer process.

And what we're asking the FDA for is alignment with our analytical comparability plan. So that'll be the -- that's the primary objective, and the primary questions that were in the briefing book center around analytical comparability. The...

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Christopher Lawrence Howerton, Jefferies LLC, Research Division - Equity Analyst [14]

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And then I guess for the clinical meeting too, yes, so with a similar question, I suppose.

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Thomas R. Cannell, Sesen Bio, Inc. - President, CEO & Director [15]

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Yes. So of course, that's a pre-BLA meeting. That'll focus on the clinical side. We have the luxury of that because we covered CMC separately. But of course, we want to show the totality of the data. As I mentioned with the summary slide that we put in the deck, that really shows you the overall story that will show the efficacy and safety data and the overall, we think, benefit-risk profile, which is very compelling. We want to get feedback from the agency as does that data set suffice for BLA submission.

And then we just -- we want to get alignment about -- very clear alignment about the regulatory path forward. There's a lot that you will learn about -- from those meetings at our regular submission, at rolling submission, priority review or not, is it accelerated approval or full approval you're going after? So there's a set of secondary questions that we'll ask, but the primary question is about the adequacy of the 12-month data set that we'll be submitting, that you all saw today.

We've tried to be very transparent, as you know. So we had a call in January, we had a call in March, now we have a call today in May. We will be very transparent as well as we have those FDA meetings. As soon as we feel confident in the response from the agency, which usually means we have the actual meeting minutes, then we will be very transparent and come out with a press release or a call to make sure you all know the outcome of those meetings.

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Christopher Lawrence Howerton, Jefferies LLC, Research Division - Equity Analyst [16]

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Got it. Okay. That's perfect. And then outside of alignment with the FDA and obviously, the topics that you just discussed, Tom. Are there other operational activities or gating factors to that BLA submission that you're aware of right now that you have to kind of execute on?

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Thomas R. Cannell, Sesen Bio, Inc. - President, CEO & Director [17]

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Yes. I think the last gating factor has to do with Module 3, which is CMC, just in terms of how much data the agency's looking for. From a stability, how many PPQ runs. Those types of issues, we'll be talking to agency about. I think as I mentioned on the last call, I haven't really guided yet in terms of timing of BLA submission or timing of -- anticipated timing of approval, but we think once we get through these meetings over the next couple of months, then we'll have a better opportunity to give specific guidance, but that's probably the last gating issue that we're looking at, Chris.

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Operator [18]

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And our next question comes from Swayampakula Ramakanth with H.C. Wainwright.

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Swayampakula Ramakanth, H.C. Wainwright & Co, LLC, Research Division - MD of Equity Research & Senior Healthcare Analyst [19]

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Most of my questions have been answered, but I just have one quick question. So of the many data points that you've discussed, and you also have it on the slides, which of these do you think is important for the FDA approval process and for commercialization?

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Thomas R. Cannell, Sesen Bio, Inc. - President, CEO & Director [20]

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Yes. So the -- thank you, RK. That's a -- it's a great question. I really feel -- and we try to kind of depict it graphically if you go to Slide 7. We -- in all the interactions that we've had with the FDA, we really feel like it's risk-benefit. So they take all of the efficacy data, and they view it in context of all the safety data. And they ask themselves, "Is that a favorable risk-benefit profile?" So the FDA views things, I think, very empirically, and they view the complete data set.

Commercially, I think there are very different things. As I mentioned, it's not an endpoint in our trial, but I think partial response rate is very relevant to physicians according to what we've heard. We know the durability of response is very important to physicians and obviously to patients. But as I mentioned, probably time to cystectomy is the most motivating endpoint that we will have commercially for payers.

As you know, there are many estimates that say the cost -- the 3-month cost of radical cystectomy is $35,000 to $40,000. And then because of the high morbidity and the readmission rates into the hospital for those patients, those costs just continue to escalate. So payers are very interested in products that have compelling time to cystectomy data.

And then of course, patients -- so many patients will do anything to keep their bladder, they suffer through so many courses with BCG. We hear patients say all the time that taking BCG is like having hot lava in your bladder. It's excruciating, but it shows how committed the patients are to preserving their bladder and to not having radical cystectomies. So we think that the meaningful time to cystectomy data will be a very motivating factor for -- not only for patients but often for their families and for caregivers as well.

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Swayampakula Ramakanth, H.C. Wainwright & Co, LLC, Research Division - MD of Equity Research & Senior Healthcare Analyst [21]

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And one other question I had was, in your slides, you had something about radical cystectomy being recommended to like 60% to 70% of the patients. At any point, do you know -- after the use of Vicinium, do you have an idea of how many patients get to cystectomy? Has that been looked at, at all in your follow-up? And also, do you think you have to go through an ADCOM, is that -- they will come up at a decision point with the FDA?

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Thomas R. Cannell, Sesen Bio, Inc. - President, CEO & Director [22]

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Yes. Thank you. So let me talk about the cystectomy piece, and then I'll talk about the need for an ADCOM.

So yes, currently, given the data that we have, obviously, the trial is still ongoing, so the data could still end it up significantly better, but we know that the average time to cystectomy for patients that -- in our trial is approximately 29 months. And again, as you know, in our clinical trial, we track the patients for 2 years on product up to 24 months until these -- they drop out of the trial, or they're successful at 24 months. Then we track them for another 2 years with quarterly check-ins.

So we will continue to gather, I think, very impressive time to cystectomy data as we do those -- as we do that tracking. So it -- that's the reason that the final clinical study report isn't estimated to come out until mid-2022. But every 3 months, we will get more important data on time to cystectomy, and I think it'll tell a stronger and stronger story. So that's where we currently are with -- and we'll just continue to provide updates.

Regarding the need for an ADCOM. I think there are always a couple of variables in terms of whether an ADCOM is required: I would say first is to what extent is the BLA submission aligned with FDA guidance; and second, to what extent is there a question about how clinically meaningful the data are.

Based on our understanding of how the FDA makes decisions on ADCOMs, we feel that it's unlikely that one will be required for this review because of how straightforward the data set are, but that is something we'll certainly gain much more insight on between now and BLA submission, and we'll definitely keep everyone updated on that.

Did you have another follow-up, RK?

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Swayampakula Ramakanth, H.C. Wainwright & Co, LLC, Research Division - MD of Equity Research & Senior Healthcare Analyst [23]

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That's it for now, Tom.

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Operator [24]

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Ladies and gentlemen, this now concludes our Q&A session of today's call. I would now like to turn the call back over to Tom Cannell for any closing remarks. Sir, you may proceed.

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Thomas R. Cannell, Sesen Bio, Inc. - President, CEO & Director [25]

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Well, thank you, operator. So the Q&A was a little shorter than we expected, and we have a few minutes. So I'll just take a couple of minutes for some very high-level closing thoughts.

This year alone, 80,000 patients will be diagnosed with bladder cancer in the United States, and 17,000 patients will die. Once you're diagnosed with bladder cancer, there's a long, humbling, arduous journey until the patient is left with only one medical option: radical cystectomy. Bladder cancer is one of the worst patient journeys of any cancer, according to the NIH. And the impact on the patients' quality of life is profound.

Despite this huge unmet need, only 3 products have ever been approved for non-muscle invasive bladder cancer in the past 100 years, and only one is used with any frequency. That's BCG, and we are once again seeing global shortages of BCG, leaving patients with few if any options.

At Sesen, we have been working closely with the FDA for over 10 years to make sure our preclinical and clinical programs for Vicinium are fully aligned with their guidance and their expectations. And we have been fully transparent with all of you today regarding the Phase II and Phase III data so that you can come to your own conclusions on the regulatory and commercial path forward. We have 2 meetings with the FDA coming up in the next 4 weeks, and we will update you on those meetings as quickly as possible.

And so really for us, it's an execution story. We have a laser focus on our mission to save and improve the lives of patients suffering from bladder cancer, and we very much appreciate your engagement and your support along the way.

So that concludes our call today. Thank you so much for calling in, and have a great week. Operator?

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Operator [26]

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Ladies and gentlemen, thank you for attending today's conference. This does conclude the program, and you may all disconnect. Everyone, have a great day.