Cellectar (CLRB) Q3 2026 Earnings Call Transcript

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DATE

Tuesday, Nov. 10, 2026

CALL PARTICIPANTS

• President and CEO - Jim Caruso
• CFO - Chad Kolean
• Chief Operating Officer - Jarrod Longcor
• Managing Director at Precision AQ - Ann-Marie Fields

TAKEAWAYS

• Cash and Cash Equivalents -- $24.6 million as of Sept. 30, 2026, compared to $13.2 million as of Dec. 31, 2025, reflecting net proceeds of approximately $31.7 million from a May 2026 oversubscribed financing.
• Research and Development Expenses -- $5.4 million, an increase from $2.5 million due to the initiation of the phase III confirmatory trial for iopofosine I-131 and increased activity in the phase I-B triple-negative breast cancer trial.
• Net Loss -- $8.0 million, or $0.46 per share, compared with $4.4 million, or $1.41 per share, driven by higher clinical development costs.
• General and Administrative Expenses -- $2.7 million, compared to $2.3 million in 2025, primarily resulting from increases in professional fees and personnel costs.
• CLOVER-WaM Post-BTKi Major Response Rate -- 79.2%, in a subgroup of Waldenström's macroglobulinemia patients treated immediately following Bruton Tyrosine Kinase inhibitor therapy.
• Median Duration of Response -- 16 months, for the same post-BTKi patient population, demonstrating durability in a heavily pretreated demographic.
• Overall Response Rate -- 87.5%, for the post-BTKi subgroup analysis presented at the International Workshop for Waldenström's Macroglobulinemia.
• Treatment Free Survival -- 19.1 months, for the evaluable patient subset treated immediately following BTKi therapy.
• Phase I-B Dosimetry Study Enrollment -- 20 to 30 patients, focusing on newly diagnosed and relapsed Waldenström's macroglobulinemia patients to evaluate tissue uptake and clinical activity.
• Confirmatory Phase III Study Target -- 100 patients per arm, evaluating progression-free survival as the primary endpoint in a randomized controlled trial design.
• NDA Submission Timeline -- First half of 2027, for the accelerated approval of iopofosine I-131 in patients with Waldenström's macroglobulinemia.
• Cash Runway -- Into the second quarter of 2027, which management stated is sufficient to fund the initiation of the confirmatory phase III trial and the planned NDA submission.
• Milestone-Based Capital -- $105 million, available in addition to the $35 million upfront payment from the financing completed in May 2026.
• DLBCL Case Study Durability -- 8 years, representing a complete response in a high-grade double-hit diffuse large B-cell lymphoma patient following a single administration of iopofosine I-131.
• European Submission Deferral -- Approximately 9 months, a strategic decision to prioritize U.S. regulatory review and prevent adverse impacts on domestic pricing.
• Confirmatory Trial Startup -- On track to dose the first patient in the first quarter of 2027 following the activation of initial clinical trial sites.
• CLR 125 Data Presentation -- Fourth quarter of 2026, at the San Antonio Breast Cancer Symposium, covering initial dosimetry and safety data for the triple-negative breast cancer program.

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RISKS

• Longcor stated, "This decision reflects the potential for near-term U.S. approval and the risk that establishing a European price first could adversely affect iopofosine's U.S. pricing," regarding the deferral of marketing authorization submissions in Europe.
• Management noted that Grade 3 or higher treatment emergent adverse events in the post-BTKi patient subgroup were limited to cytopenias.

SUMMARY

Cellectar Biosciences, Inc. (NASDAQ:CLRB) reported financial and operational progress for its radiopharmaceutical pipeline, specifically highlighting the regulatory pathway for its lead asset, iopofosine I-131. Management indicated the company is transitioning toward a commercial-stage entity, with potential U.S. approval for the treatment of Waldenström's macroglobulinemia anticipated as early as late 2027 or early 2028. Strategic prioritization includes the initiation of a phase III confirmatory trial required for accelerated approval and the deferral of European filings to prioritize domestic pricing and regulatory review.

• CEO Caruso stated, "Today, we believe we are entering the most significant value-creating phase in our company's history as we advance towards several potentially transformational milestones."
• Management reported the phase I-B dosimetry study will evaluate iopofosine I-131 in first-line and second-line Waldenström's macroglobulinemia patients, potentially expanding the market beyond the currently targeted post-BTKi indication.
• COO Longcor noted that the company is compressing the typical nine to 12-month site activation process into five to six months for the confirmatory phase III trial.
• The company confirmed that three poster presentations at the upcoming American Society of Hematology meeting will include 12-month follow-up data and the design of the phase III study.
• Longcor indicated that 5% to 15% of the phase III study should be enrolled by the time of regulatory action to demonstrate diligence to the FDA.

INDUSTRY GLOSSARY

• Iopofosine I-131: A phospholipid drug conjugate designed to deliver targeted iodine-131 radiation to cancer cells.
• Waldenström's Macroglobulinemia (WM): A rare type of B-cell lymphoma characterized by the overproduction of monoclonal IgM antibody.
• BTK inhibitor (BTKi): A class of drugs that blocks Bruton’s tyrosine kinase, often used to treat various B-cell malignancies.
• Phospholipid Drug Conjugate (PDC): A delivery platform that uses phospholipid ethers to selectively target and deliver therapeutic payloads to cancer cells.
• CLR 125: An iodine-125 Auger-emitting radiotherapeutic candidate currently being evaluated for triple-negative breast cancer.
• Cytopenias: A condition where there is a lower-than-normal number of blood cells, such as white blood cells, red blood cells, or platelets.

Full Conference Call Transcript

Operator: Good morning, ladies and gentlemen, and welcome to the Cellectar Biosciences Third Quarter Earnings Conference Call. At this time, all lines are in listen-only mode, and following the presentation, we will conduct a question-and-answer session. If at any time during this call you require immediate assistance, please press star zero for the operator. This call is being recorded on Tuesday, November 10, 2026. I would now like to turn the conference call over to Ann-Marie Fields, Managing Director at Precision AQ. Please go ahead.

Anne Marie Fields: Thank you. Thank you, operator. Good morning, and welcome to Cellectar Biosciences Third Quarter 2026 Financial Results and Business Update Conference Call. Joining us today from Cellectar are Jim Caruso, President and CEO, who will provide an overview of the company's progress, before turning the call over to Chad Kolean, CFO, for a financial review of the quarter. Following this, Jarrod Longcor, Chief Operating Officer, will give an update on the company's progress and plans for its promising clinical development pipeline of radiopharmaceuticals. Cellectar issued a press release earlier this morning detailing the content of today's call. A copy can be found on the Investor page of Cellectar's corporate website.

I want to remind callers that the information discussed on the call today is covered under the safe harbor provisions of the Private Securities Litigation Reform Act. I caution listeners that management will be making forward-looking statements. Actual results could differ materially from those stated or implied by our forward-looking statements due to risks and uncertainties associated with the business. These forward-looking statements are qualified in their entirety by the cautionary statements contained in today's press release and in our SEC filings. The content of this conference call contains time-sensitive information that is accurate only as of the date of this live broadcast, November 10, 2026.

The company undertakes no obligation to revise or update any forward-looking statements to reflect events or circumstances after the date of this conference call and webcast. As a reminder, this conference call and webcast are being recorded and archived. We will begin the call with prepared remarks, and then we will open the line for your questions. I will now turn the call over to Jim Caruso. Jim?

Jim Caruso: Thank you, Ann-Marie. Good morning, everyone, and thank you for joining us. The third quarter was a highly productive and strategically important period for Cellectar Biosciences, as we continued to execute against what we believe is a defined path toward accelerated approval and potential commercialization of Iopofosine I-131 for patients with relapsed or refractory Waldenström's Macroglobulinemia, or WM. Over the last several quarters, we have systematically reduced risk across the clinical, regulatory, and operational components of our WM strategy.

Today, we believe we are entering the most significant value-creating phase in our company's history as we advance towards several potentially transformational milestones, including the recent initiation of our confirmatory phase III study, advancement of our phase I-B dosimetry study, which includes the option to enroll first and second-line WM patients, and our planned NDA submission in the first half of 2027 seeking accelerated approval. Most notably, we continue to make excellent progress with site activation and study startup activities for our confirmatory phase III trial and remain on track to dose the first patient in the first quarter of 2027.

The initiation of patient dosing represents an important inflection point in our regulatory strategy, as it is expected to support a key requirement of our accelerated approval pathway. Importantly, we believe Iopofosine I-131 could be approved and become commercially available as early as late 2027 or early 2028, positioning Cellectar to transition from a development-stage biotechnology company into a commercial-stage radiopharmaceutical company. We believe this opportunity represents a transformative milestone for the company and one of the most significant value drivers in our history. In parallel, we continue to strengthen the clinical foundation supporting the program.

Throughout 2026, we have generated and presented a growing body of evidence that we believe reinforces the differentiated profile of Iopofosine I-131, including its potential to deliver durable responses in heavily pretreated patients with significant unmet medical need. In October, our team presented additional analysis from the CLOVER-WaM study at the International Workshop for Waldenström's Macroglobulinemia, demonstrating a major response rate of 79.2% and a median duration of response of 16 months in patients treated immediately following BTK inhibitor therapy. We believe these findings are particularly meaningful because they reflect the same patient population that will be evaluated in our confirmatory phase III trial and further support the clinical rationale for our accelerated approval strategy.

Most recently, we announced three presentations at the upcoming American Society of Hematology Annual Meeting, or ASH, where we will continue expanding the growing body of evidence supporting Iopofosine I-131 in WM. These presentations include updated 12-month follow-up data from the CLOVER-WaM study. Analysis evaluating duration of response based on prior lines of therapy, and the first public presentation of our confirmatory phase III trial design. Collectively, these data continue to reinforce a highly consistent efficacy and safety profile while also suggesting that patients treated earlier in their disease course may experience a particularly durable benefit.

As we continue to build this increasingly robust clinical package, our confidence in the potential of Iopofosine I-131 and the strength of the overall opportunity continues to grow. Beyond WM, we are also seeing encouraging evidence supporting the broader applicability of iopofosine across hematologic malignancies. During the quarter, we presented a compelling case study involving a patient with diffuse large B-cell lymphoma who achieved a complete response following a single administration of iopofosine and maintained that response for more than eight years. While this represents a single patient experience, it highlights the remarkable durability that may be achievable with targeted radiotherapeutic therapy and further underscores the broader potential of our technology.

In addition to expanding the clinical evidence supporting Iopofosine I-131, we also continued to showcase the scientific foundation underlying our platform. During the quarter, we hosted a successful educational webinar highlighting the unique biology of phospholipid ethers and the rationale behind our proprietary Phospholipid Drug Conjugate, or PDC, technology platform. We were very encouraged by the level of participation and engagement, which we believe reflects growing recognition of the platform's potential and its ability to move across multiple therapeutic opportunities. If you haven't listened in to the webinar or seen it, you can find it on the investors section of our website.

Importantly, the PDC platform serves as the foundation not only for Iopofosine I-131, but also for our broader radiopharmaceutical pipeline. As we advance additional programs such as CLR 125, we are expanding a diversified portfolio of targeted radiotherapeutics that has the potential to create meaningful long-term value well beyond a single asset. Of course, I remain proud of the execution demonstrated by the entire Cellectar team throughout 2026. We have continued to advance key clinical and regulatory initiatives, expand the body of evidence supporting our lead program, strengthen the validation of our platform, and position the company for what we believe could be a transformational period ahead.

Supported by our balance sheet and the resources necessary to execute our strategy, we enter the final months of the year with significant momentum and a clear focus on delivering the milestones that we believe can create substantial value for both patients and shareholders. We look forward to reviewing our third quarter accomplishments in greater detail today and discussing the exciting opportunities that lie ahead. With that overview, I will now turn the call over to Chad for a review of our financial results. Chad?

Chad Kolean: Thank you, Jim, and good morning, everyone. I will discuss our financial results for the period ended September 30, 2026. We ended the third quarter with cash and cash equivalents of approximately $24.6 million, compared to $13.2 million as of December 31, 2025. As previously reported, we successfully completed an oversubscribed financing of up to $140 million in early May, which is composed of an upfront payment of $35 million and $105 million in milestone-based capital. Our cash runway extends into the second quarter of 2027, which is sufficient to deliver important catalysts in our planned operations, including the initiation of our confirmatory phase III trial and potential new drug application submission.

With respect to our results from operations, research and development expenses for the three months ended September 30, 2026, were approximately $5.4 million, compared to approximately $2.5 million for the three months ended September 30, 2025. The overall year-over-year increase in R&D largely reflected costs associated with the initiation of the phase III confirmatory trial, as well as increased activity in the phase I-B CLR 125 trial in triple-negative breast cancer. General and administrative expenses for the three months ended September 30, 2026, were $2.7 million, compared to $2.3 million for the same period in 2025. The increase in G&A was primarily the result of increases in professional fees and personnel costs.

Net loss for the three months ended September 30, 2026, was $8.0 million, or $0.46 per share, compared with $4.4 million, or $1.41 per share, during the three months ended September 30, 2025. We remain focused on our Iopofosine I-131 program and strategic advancement toward multiple important milestones. I will now turn the call over to Jarrod for his comments on our regulatory and clinical advancements.

Jarrod Longcor: Thank you, Jim, and good morning, everyone. As Jim noted, Cellectar has entered a particularly important period in its evolution, where successful execution against key clinical, regulatory, and operational milestones has the potential to create substantial value for patients and shareholders alike. Our primary focus remains advancing Iopofosine I-131 for accelerated approval in post-second line, post-exposure to BTKi and/or BTK inhibitor therapy in relapsed refractory Waldenström's macroglobulinemia, a patient population for which treatment options remain limited despite meaningful advances over the past decade. We have made significant progress establishing the operational foundation required to launch our global phase III confirmatory trial.

Site activation activities are underway, and we remain on track to dose the first patient during the first quarter of 2027. Importantly, this study serves both a regulatory and commercial purpose. First, it fulfills the FDA's expectation for a confirmatory study to be initiated at the time of submission and underway at the time of regulatory action, as outlined under the FDORA Act and accelerated approval framework. Second, it is expected to generate additional data that can further strengthen the long-term clinical and commercial positioning of Iopofosine I-131.

With initiation of patient dosing expected in the coming months and our NDA submission targeted for the first half of 2027, we believe Cellectar now has a clear and actionable roadmap toward potential commercialization. If approved, Iopofosine I-131 could become commercially available in the U.S. as early as late 2027 or early 2028, representing a significant milestone in the company's transition towards becoming a commercial-stage radiopharmaceutical company. As it relates to Europe, in light of the introduction of most-favored-nation pricing in the United States, we have determined that delaying our European commercial or conditional marketing authorization submission for iopofosine is the most strategically advantageous path forward.

This decision reflects the potential for near-term U.S. approval and the risk that establishing a European price first could adversely affect iopofosine's U.S. pricing. We therefore expect to defer the European submission by approximately nine months, allowing the U.S. regulatory review and related pricing discussions to advance before establishing the European. We believe this sequencing will better position Cellectar to preserve iopofosine's commercial value and maximize its potential global revenue opportunity. During the past quarter, we also initiated a phase I-B dosimetry study of Iopofosine I-131 in patients with WM. The study is expected to enroll 20-30 patients, including both newly diagnosed and relapsed patients, with no specific prior treatment requirement.

Leveraging our ability to directly image iopofosine, we will evaluate its uptake in various tissues using the same dosing regimen employed in our phase II-B and phase III confirmatory studies. In addition to characterizing tissue uptake, the study will generate further efficacy and safety data, expanding our understanding of iopofosine's clinical profile across the broader WM population. Further supporting this strategy, a post-hoc analysis from the CLOVER-WaM study, which will be presented at ASH, suggests that patients who receive iopofosine after fewer prior lines of therapy may achieve more durable responses. Our phase I-B study provides an opportunity to prospectively evaluate these observations and further assess Iopofosine I-131's potential in earlier lines of treatment.

These findings could inform future development and broaden the long-term commercial opportunity beyond the post-BTKi indication targeted for full market approval. While we continue to build the operational foundation for regulation and commercialization, we are simultaneously expanding the already compelling body of clinical evidence supporting Iopofosine I-131. As Jim mentioned, in October, we presented new data at the International Workshop for Waldenström's Macroglobulinemia, where a subgroup analysis was performed on participants from CLOVER-WaM trial who were treated with BTKi immediately prior to receiving Iopofosine I-131.

Despite representing a particularly challenging and refractory patient population, these patients achieved an overall response rate of 87.5%, a major response rate of 79.2%, and clinical benefit rate of 100%, and a median duration of 16 months. These findings are particularly encouraging because iopofosine-targeted radiotherapeutic mechanism operates independently of the BTK pathway. As a result, we believe iopofosine has the potential to provide a meaningful treatment option for patients whose disease has progressed following BTK inhibitor therapy, an area where significant unmet need continues to exist, and to Jim's earlier point, the patient population we will evaluate in the confirmatory phase III trial.

As we look across the growing body of data generated to date, we believe the clinical profile of Iopofosine I-131 continues to strengthen and differentiate itself within the treatment landscape for relapsed refractory WM. The analysis presented throughout the year combined the additional data to be shared at ASH continue to reinforce the consistency, durability, and clinical relevance of the responses observed across multiple patient populations. The planned initiation of our phase III confirmatory trial of iopofosine in WM represents a major step for the Cellectar team as we advance discussions with the FDA, moving the therapy closer to potential accelerated approval submission. Beyond WM, we continue to see an evidence supporting the broader potential of iopofosine across hematologic malignancies.

We recently reported a remarkable case study in diffuse large B-cell lymphoma, or DLBCL, demonstrating a complete response lasting more than eight years following treatment with Iopofosine I-131 in a heavily pre-treated patient. The patient had received four prior lines of therapy and presented with a high-grade double-hit disease characterized by both MYC and BCL2 alterations, a particularly aggressive form of lymphoma associated with poor outcomes. Following the single administration of Iopofosine I-131 in March of 2018, the patient achieved a partial response by day 48 and a complete response by day 85, as confirmed by both investigator and sponsor assessment. Imaging demonstrated complete resolution of by day 85.

The patient remains in complete response over eight years later and no disease progression and requiring no additional anti-cancer therapy. While representing a single patient experience, these findings further highlight the potential durability of response that may be achieved through targeted therapy and provide additional support for iopofosine across B-cell malignancies. Collectively, the breadth of data generated across WM, DLBCL, and other hematologic malignancies continues to reinforce the strength of underlying PDC platform and its potential applicability across multiple cancer settings. During the quarter, we also hosted a successful educational webinar focused on our proprietary Phospholipid Drug Conjugate platform.

The webinar highlighted the growing body of preclinical and clinical evidence supporting the platform's ability to selectively target and deliver therapeutic payloads to cancer cells while minimizing off-target exposure. We believe the strong engagement we received reflects growing recognition of the platform's potential to support a diversified pipeline of targeted radiotherapeutic programs, extending well beyond our lead WM opportunity. This platform also serves as the foundation of our next-generation radiopharmaceutical programs. Beyond Iopofosine I-131, we continue to advance CLR 125, our iodine-125 Auger-emitting radiotherapeutic candidate in triple-negative breast cancer. Enrollment continues, and we remain on track to present initial dosimetry and safety data later this year at the San Antonio Breast Cancer Symposium.

Preclinical studies in triple-negative breast cancer models have demonstrated encouraging tumor targeting, uptake, and anti-tumor activity, supporting our continued enthusiasm as the program progresses through clinical development. Triple-negative breast cancer remains an area of substantial unmet medical need, and we believe CLR 125 represents an important opportunity to demonstrate the versatility of our PDC platform in solid tumors. Positive data could further validate our approach and create an additional source of long-term value creation beyond our WM franchise. Taken together, we believe the progress achieved during the quarter highlights both the maturity of our lead program and the expanding potential of our broader radiopharmaceutical franchise.

We are advancing towards multiple potentially value-defining milestones, including initiation of the confirmatory phase III trial, continued execution of the phase I-B dosimetry study, presentation of additional WM data at ASH, and NDA submission in the first half of 2027. Coupled with ongoing advancement of CLR 125, and our broader PDC platform, we believe Cellectar is exceptionally well-positioned for a transformational period of clinical, regulatory, and corporate growth. We remain focused on disciplined execution and look forward to updating you on the continued progress in the quarters ahead. With that, I will turn the call back to Jim for closing remarks.

Jim Caruso: Okay. Thank you, Jarrod. As we look ahead, we are entering an exciting time for Cellectar. We have established a clear regulatory pathway for Iopofosine I-131, generated a substantial and expanding body of clinical evidence supporting its use in WM, initiated activities required for both our phase III confirmatory study and phase I-B dosimetry study, and remain on track for an NDA filing in the first half of 2027. Importantly, these milestones are not isolated events. Together, they support our broader objective of bringing Iopofosine I-131 to patients and transitioning Cellectar into a commercial-stage radiopharmaceutical company.

With a potential approval as early as late 2027 or early 2028, continued advancement of our PDC platform, and multiple upcoming clinical catalysts across the portfolio, we believe we are exceptionally well-positioned for a period of meaningful execution and value creation. We remain focused on disciplined execution, continued clinical innovation, and building long-term value for patients and shareholders alike. As always, we thank you for your continued support. Operator, we are now ready to take questions.

Operator: Thank you. Ladies and gentlemen, we will now begin the question and answer session. Should you have a question, please press the star followed by the one on your touch-tone phone. You will then hear a prompt that your hand has been raised. Should you wish to decline from the polling process, please press star followed by the two. If you are using a speakerphone, please lift the handset before pressing any keys. One moment, please, for your first question. Your first question comes from Kevin DeGeeter from Ladenburg. Please go ahead.

Kevin DeGeeter: Hey, yeah. Thanks for this call. Very informative. Just really two for us, maybe firstly on Iopofosine I-131 dosimetry study, really kind of three parts. Can you comment on when you hope to kick off, first patient in? As we think about second-line WM patients, is there any risk here that the dosimetry enrollment competes with the phase III confirmatory enrollment, population and clarity there? I believe this is an open-label study, so just, how do you think about the cadence of potentially, any comments on clinical activity of patients enrolled in the dosimetry study, particularly given that they are potentially some of the similar line patients that we will be enrolling into the phase III study? Thanks.

Jim Caruso: No. Thank you, Kevin. Appreciate the question, and it is an important one on a lot of different levels for us. We are running this study in parallel, as you cited, with our confirmatory phase III study. We anticipate first patient in and around the same timeframe as we have outlined for the confirmatory. So, think in and around the first quarter of the year. As you cited, we do not anticipate any issues relative to patient enrollment. The sites that we are using for the phase I-B are predominantly different from those from the confirmatory study, and we are advancing, quite frankly, very rapidly there with site activation.

We could have Jarrod talk to some of the details, as I will turn this over to him in a moment. You are correct. I mean, we are excited about the potential, looking at these secondary endpoints in terms of advancing further upstream in the treatment algorithm for WM. Jarrod can touch on an abstract that we are presenting at ASH that clearly delineates an opportunity for both response rate and the durability, in particular, the durability of those responses being enhanced as iopofosine moves further upstream in terms of treatment, i.e., from a median of fifth line, even relative to third line, there's a substantial difference.

I've probably taken a lot of talking points away from Jarrod, but he's intimately involved with the studies, providing oversight of the activities as we currently sit. So, I'll turn it over to Jarrod for some additional detail.

Jarrod Longcor: Sure. Thank you, Jim. Thank you, Kevin, for the great question. As Jim outlined, yeah. As you think about the dosimetry study, I think our first site will be active in that study earlier than the confirmatory study, but the likely timing of first patient in, as Jim said, is probably going to be similar. We are, as Jim outlined, as you think about the potential competition between that study and the confirmatory study, one, because it's slightly different patients, moving even earlier, so an all-comers sort of strategy, it opens the door for patients that would not be in the confirmatory study. So, we expect to see some level of that.

Second, as Jim outlined, we're going to be looking at where we have sites that are different from those in the confirmatory study and looking at different sort of how we spread things out regionally and think about where the patient populations are and where we don't draw more from certain places and others. Probably the third component is we're focusing in on centers that are experts at dosimetry and imaging. This is a bit different than just treating, right?

So, you have centers that might be experts at treating a patient, but they're not used to taking these type of specialized dosimetry images that allow the actual calculation and understanding of the accumulation of the drug in the various tissues. So, that we also think will differentiate and separate us. I will say one of the other-

Jim Caruso: And-

Jarrod Longcor: added benefits Go ahead, Jim.

Jim Caruso: No, finish your thought.

Jarrod Longcor: Jarrod? Sorry, I missed you. Yeah, sorry. I missed what you said there.

Jim Caruso: No, finish your thought, my friend.

Jarrod Longcor: Oh, okay. Sorry. Where I was headed was the third element in that is the fact that, in several cases, there is the, obviously, this, the confirmed study of last role that may have also failed in our competitor right? So, obviously, it opens up for additional patients even after that. So, it's, while there- In my opinion, there's a lot less competition because it gives a site greater flexibility on how they think about their processing and enrollment of patients across both studies for sites that have both studies. I'll pause before I get into the potential impacts, because it sounded like, Jim, you had something else to say on that subject.

Jim Caruso: Now, I think oftentimes we get caught up in the activity of the drug, and we clearly believe as we advance earlier in lines of therapy, we should and anticipate better response and greater durability of response. Sometimes we forget about the benefits of safety, especially in this older patient population. Jarrod, as an example, not being subject to four lines of prior therapies, many of them beating up the bone marrow, we would also potentially anticipate a cleaner adverse event profile. Is that a fair statement?

Jarrod Longcor: Yeah. Actually, when I got to the impact on the results, that was sort of where I was going to head. Thank you. If you think about the drugs that these patients are being treated with, obviously BTK inhibitors or BTKIs come with their sort of aspect as an adverse event profile. These patients are also getting other drugs, proteasome inhibitors, alkylating agents, other things that are myeloablative. That myeloablation increases their likelihood and sensitivity to future therapies in the sense of adverse event profile. In our case, obviously, a beta emitter targeting the bone marrow, you would expect some level of cytopenia.

Patients who have had proteasome inhibitors or alkylating agents, you would expect them to have higher rate of cytopenia, and potentially even more as they move through multiple lines and their disease becomes more aggressive, their bone marrow reserves gets reduced. Their bone marrow, as mentioned, the damage is there, but also just generally their ability to recover goes down with age. One would expect that. As you move to an earlier line of patient, less treated, younger by age, all of those elements start to reduce, you would expect a cleaner and better profile.

If you look at iopofosine's profile, where essentially the only adverse events we get are transient hematologic suppression or cytopenias, you could expect that cytopenia rates could reduce as you move to an earlier line setting, making the profile even that much better, in addition to the additional benefits associated with the durability and potentially increased response rates that we could see.

As Jim outlined in his initial response to it, we do expect that, and we do think one of the interesting things is that with the 20-30 patients in the dosimetry study, we will be having a line of sight on an earlier line patient outcome that we're able to report out on, whereas it relates to the confirmatory study, we're unable to give any information. We will be blinded during that. It allows us to have some visibility, is what I'll call it, to potentially how the confirmatory study is playing out. I think that's a huge benefit to us, to patients, to investigators, and to shareholders.

Kevin DeGeeter: No, great. Then just maybe one more for me to kind of level set for everybody. How many patients do we have to enroll in the confirmatory phase III to file? Is that kind of a fixed number? Is it a range? Is it a little bit of a moving target? Yeah, I mean, I appreciate the guidance with regard to timeline, but what does that imply with regard to actual enrollment?

Jim Caruso: Yep. I think it's all of the above. I'll have Jarrod talk to. There's no real specific guidance, but we believe we have line of sight on what the FDA may be anticipating or may find acceptable. I'll have Jarrod talk to some of the details and discussions we've had, both with third-party consultants, as well as our own internal assessment.

Jarrod Longcor: Yeah. Thank you, Jim. The concept here is, and I would go with your latter statement, which is, it's sort of a moving target. The FDA has been intentionally vague. Congress didn't, under the FDORA Act, Congress did not give them specifications. They left it open to the FDA. The FDA utilizes that to use it in a case-by-case setting. In the case of different drugs, that allows them the flexibility to determine what initiation meant and what ongoing means as it relates to the act.

I think what we've heard is that for the most part, as long as you actively have a site or two open, that implies that your study has been initiated and you could, in theory, file. As long as you have some level of enrollment going on, the study is ongoing, and that means at least one patient. I will say the FDA's feedback has been, it's at least one patient, but not fully enrolled. That's about as detailed as they get.

As Jim said, in discussions with various consultants, we've come away with the concept that somewhere between maybe between 5%-15% of the study should be enrolled at the time to show that you're being diligent against executing the study. I think that's somewhere where we're going to sort of target. We want to make sure that we're showing the FDA that we're able to enroll the study.

Clearly, with us being a U.S.-based company, most of our sites that are in the U.S. will be the earlier ones to be opening, and that's where we expect to get a significant number of patients, which is another part of the FDA's concern, or desire, which is to make sure patients are representative of the U.S. treatment paradigm, which means they would like to see greater numbers of U.S. patients across the phase IIb and the phase III confirmatory study. By having those sites being open earlier in the U.S., we tend to be able to have the capability to enroll more U.S. patients and satisfy that. That helps as well with the study design.

Jim Caruso: Jarrod, for sake of clarity, the 5%-15% of the patients that we've cited, is that at the time of submission or at time of regulatory action?

Jarrod Longcor: Thank you. That's at the time of regulatory action. That's not at the time of submission. So, just so that people are clear on that, you could enroll two, three patients early, then file, and depending on your enrollment rate and your planned enrollment rate and what you estimate, you could be easily over 5% or 10% of the patients enrolled after six/eight months for the accelerated approval process, based off the enrollment timelines.

Kevin DeGeeter: Great. Thanks for taking our questions.

Jim Caruso: Thanks, Kevin.

Operator: Thank you. Your next question comes from Kemp Dolliver from Brookline Capital Markets. Please go ahead.

Kemp Dolliver: Great. I'm going to ask a question or two about the phase III and then flip over to the I-B. Just to continue on the phase III briefly, given where you are with site activation, I mean, how many sites have you activated, and then what is the good ballpark timeline between activation and then recruiting?

Jim Caruso: Sure. I will say this. I'll open with this, Kemp. First of all, thank you for participating in the call and for your questions. As always, they're appreciated. I will say we're very pleased with the progress we're making with engaging academic centers as well as integrated oncology delivery networks out in our, the air quote, "community" here in the U.S. I say ex-U.S., really the who's who of WM catchment centers are participating. We've also received, interestingly, unaided inbound inquiries as to whether or not institutions have the opportunity to participate. We're actually moving along very rapidly. We're pleased with the response we're receiving in the community.

I think in large part, it's based on the quality of our data that's in the public domain and has been disseminated. I will also say we're receiving really exciting feedback from the WM patient community in general. As you may or may not know, it is a very tight community, a lot of communication, and there's a lot of chatter and excitement about this upcoming phase III. I would anticipate, as a result, our enrollment rates should be pretty substantial based on the high level of interest and awareness of iopofosine and the quality of its outcomes.

I'll turn it over to Jarrod without providing actual numbers, if you could provide Kemp with some sense as to timing and enrollment, et cetera.

Jarrod Longcor: Yeah. I want to stress a slightly different component for you, Kemp. Jim talked about his pride with the team's execution, and I want to echo that. Why? We're taking what is typically a 9 to 12-month process to get a site activated. Thinking about the detail and the level of detail that has to go into that, and I can walk you through all the operational steps, and we're squeezing that down into a five to six-month process. So we're doing something that is incredibly hard to do. We're working at a much faster pace than what historically is done. We're on track, as we outlined, that we're going to have several sites active and initiated this year.

Going to have, with the plan that the first patient will be enrolled in the first quarter. We're doing that at basically from a standing still spot in June till now. That's a pretty impressive feat for a pretty small team and a pretty efficient team when you think about how little we're spending to get it done. We're working pretty exhaustively to deliver and to meet the timelines both of what are expected from us, ourselves, as well as our investor community. I forget the second part of the question that was beyond site activation, so I apologize, guys. Kemp, I'm like, I can't think of a reaction.

Kemp Dolliver: Well, yeah, you kind of implied an answer given what you're saying. We're in early November. You expect to have sites activated by December 31. So, we're talking like 60 days just to throw a ballpark around it. That'd be a pretty fair estimate?

Jarrod Longcor: That is a very fair estimate.

Kemp Dolliver: Okay. Super. Thank you for. Go ahead.

Jim Caruso: Kemp, I think that you almost have to think about the sequencing of enrollment, almost similar to a portfolio, where you are going to have some activity early on, and then as we progress, I think some of the academic centers may take a little bit longer, and I think those delivery networks in the community taking a little bit less time. You will have this cadence of enrollment, and that we believe will initiate very soon. Then, we may very likely still be enrolling sites in the middle of the year for some of these more complex institutional processes.

Kemp Dolliver: That is very helpful. Thanks. Flipping over the phase I, when I read that, I cannot help escape the assumption that you could very well end up essentially competing with the BTKi. Because as you know, and have said with the treatment protocols, it is try BTKi, once you fail that, if you do, it is try whatever, throw a lot of mud on the wall clinically and see if anything sticks. Including another BTKi. So, it strikes me that there is a pretty good chance you could end up competing with the BTKi. Want to take a shot at that?

Jim Caruso: Sure. Yeah. I mean, yeah. I will provide if there is anything meaningful to describe afterwards, I will just provide it.

Jarrod Longcor: Yeah. Let me start out from, keep in mind, Kemp, and for everybody, that there are a group of patients for whom BTK will not work well, right? The MYD88 wild-type patients, when you look at the genetic profile, the BTKIs do not work well in that patient population. They tend to have a limited to no response. They tend to have very rapid progression. Obviously, for iopofosine, because our mechanism does not require that pathway, we are able to treat those patients. That represents, if you look at the total population, depending on what studies you look at, you are somewhere between 10%-20% that are just MYD88 wild-type.

You also have another patient population, different gene, different mutations, CXCR4 mutation, for whom, again, BTKIs do not work incredibly well. That represents another 10% or 15% of patients. You are looking at somewhere between, and I will just be somewhat conservative, there are 20%-30% of patients in a frontline setting for whom BTKIs, if they had another option, would not be prescribed. That is just one set. You are absolutely correct. If you just look at that group alone, that represents a patient population for whom we could immediately, in the frontline setting, be not just competing, but be recommended in front of a BTKI, because they are not recommended for those patients.

Second, and you are absolutely correct, that pending the data results, we could be in comparison or in competition to some extent for other BTK, what right now are BTKI patients. Who would that reflect? That reflects patients who have a higher propensity to be intolerant to BTKI in a meaningful way.

Those patients who might already have atrial fibrillation or cardiac issues for which you would not necessarily want to prescribe BTKI if you had another choice or a better choice, one that for which you had actual competitive data, that might be helpful, as opposed to drugs, as you just said, that are chemotherapeutic soups or salvage therapies that you are doing just because you know not to give it to this patient.

You have other adverse event profiles or patients with challenging backgrounds or comorbidities for whom you might not want to give a BTKI, but for whom iopofosine, with a fixed duration, just four doses over essentially three months, and then done, and getting two, three years of progression-free survival off a very short course of therapy, as opposed to having to take the drug every day for three years to get the same outcome. Keeping in mind that one of the challenges with BTKIs that people often forget about is while they can get you three to four years progression-free survival, you are taking that drug every day. You are spending money every month.

All of this is an impact on the patient, on their need to come back, on the non-transient nature of their adverse events, because why? They have to continue to take the drug, and that means the adverse event will continue over the course of time, which is actually why you see at 12 and 24 months, the rates of infection are quite high. The rates of neutropenia are quite high, where ours are zero. I think that's a very distinct feature, and I think that will, if moved into an early line setting, will make this drug very competitive in that space.

Jim Caruso: I am in agreement, Jarrod. The only other point that I would make, and I know this is not as clear-cut as MYD88 wild-type or mutated and the CXCR4 wild-type, but P53 as well. When you look at the demographics for our phase IIb global CLOVER-WaM pivotal trial, a substantial portion of our patient population resided in these very difficult genotypes with the MYD88, the CXCR4, and the P53. Yet we still delivered on a high major response rate and a very substantial duration of response there. So, we are excited about seeing how this drug behaves in earlier lines of therapy as well.

The only other point I do not think we touched on, Jarrod, with the phase I-B, and I know you are transitioning into that. Now, Kemp, is the potential benefit from an NCCN guideline ruling. We get a reasonable amount of first, second-line patients into phase I-B, and as you know, secondary analysis includes efficacy as well as safety, that could help support NCCN guideline positioning for earlier lines of therapy when a BTKI is, air quote, "contraindicated.

Kemp Dolliver: Right. Yeah, great. Thank you. That last comment kind of ties into my next question, is if you have a sense from FDA regarding the pathway, assuming favorable phase I-B data.

Jim Caruso: I'm sorry, Kemp, could you please repeat the first part of the question?

Kemp Dolliver: Yeah. Do you have a sense from FDA, if you're willing to go this far, as to the pathway if the phase I-B data are favorable? Everything we're looking at here suggests this could move very rapidly.

Jim Caruso: Listen, it's a fair question. I believe our accelerated approval pathway would trump this. I think we collect data here. Obviously, we have a well-thought-out, well-vetted development plan Iopofosine I-131, beyond third line and beyond, with some targeted levels of investment, both from an investigator study perspective as well as future studies. Jarrod, you're intimately involved with our discussions with the FDA. I'm not sure how we want to respond to this in terms of the FDA being comfortable advancing this into a first or second line in the early going.

Jarrod Longcor: Yeah, no, I think what I would say is, as you might expect, Kemp, we have a number, and as Jim sort of outlined, we have a number of development pathways in front of us after the approval, under the accelerated approval and then under the full approval, potentially, after the confirmatory study. As we continue to develop the drug and the asset across these different things, one could expect to see various, as Jim said, either investigator-initiated trials or other small studies that could move or provide datasets.

I think the key is, and I do think this is important, which is in the frontline setting, the FDA has a very specific, what I'll call very specific outline, which is obviously a comparative control trial, head-to-head, and executed in the patient population. I don't think that's special to us. I think that is true for any frontline setting in oncology, and I think that would be the expected plan and route. I think we, as an organization, would be laying out exactly how we see that, how best to accomplish that, considering that obviously right now, the frontline setting in a head-to-head study would likely either have to be some BTKi or something of that nature.

I think we would have to think about how best to construct and design that study to execute.

Jim Caruso: Now, having said that, the majority of products used in first and second line are all non-indicated, right? So, in second line, beyond assuming a BTKi is used in first line, in second line, you are in salvage therapy already. We do know that there is a significant portion of the population that are not BTKi eligible. So, as an indicated product, my instincts suggest that certainly in second line, this agent would be used prior to non-indicated treatments or soups that are currently used in salvage therapy.

So, I believe by design and by need, this drug would be used in certain portions of the patient population in first and second line, and I think the pathway there is through NCCN, as opposed to some organized head-to-head trial that one would consider much further downstream.

Kemp Dolliver: Understood. Thank you. Last quick question. How many sites do you expect the need for this trial?

Jim Caruso: Well, it is a great question, and there is a strategy to it as well. Certainly, we like to incorporate these oncology delivery networks just so that they can see the ease of use of Iopofosine I-131, certainly relative to other radiotherapeutics, the way this is designed, packaged, delivered, et cetera. Also, they can observe the patient journey through their systems. So, that is important to us as we think about how we build out, and I will have Jarrod talk to the number that we are thinking about, both U.S. and ex-U.S., or the global number in general.

So, we are also trying to establish regional footprints, those catchment centers that control regio-specific influence, as well as those larger, well-respected WM centers with thought leadership that have an influence in terms of prescribing behaviors throughout the U.S. We look at it not only from an end camp, but also strategically, how does it fit for us on other levels as well? We have been pretty fortunate in terms of how that puzzle, the pieces of that puzzle are coming together. I know we started with a couple of recommendations based on the CRO and our own internal work. I will have Jarrod kind of talk to that in that detail.

Jarrod Longcor: Yeah. I think to Jim's point, the strategic nature is what we are focused on, not necessarily a set number. I mean, we have our target number, and happy to share that at a high level. I think, as Jim said, if you think about this from a commercial perspective, 80% of the patients actually reside in about 15 of U.S. states. What we want to make sure is that we are where the patients are. So what we have done is specifically target centers in states where we know there is a high patient population, and we make sure that we have appropriate centers in the state or spread across the state to be attractive.

You obviously do not want to have, if you are like in Texas, you do not want to have somebody having to drive five hours to get to a clinical center for treatment, right? As much as the drug might work great for them, they are disinclined to do it. What we tried to do is identify and geographically locate centers to maximize potential ease and enrollment capability for our patients.

As Jim said, that allows us to both target large academic centers in the U.S. that would be traditional catchment centers, as well as to navigate and work with community-based operations that are more diffusely spread around and networked so that they can refer patients from some nearby locations into a treatment center that has the capability for radiopharmaceuticals.

That allows us, as Jim said, not only to give the community base who are going to be key prescribers eventually, not only to give them an opportunity to participate and understand how to utilize the drug in patient journey, but also gives them a chance to really see firsthand the benefit this can provide to the patient population and be engaged, which most of them want to do, is be engaged in clinical trials and see the drugs early and be able to offer that as a benefit to the patients.

We think through that network and through how we strategically aligned it, we will make sure and have made sure that we are covering the key parts of the U.S., even and globally, even as we think about it from Europe perspective. Again, we can look at where are the patients highly concentrated across Europe, even in Asia, where are those that fit the definition of what we need to evolve, and then we strategically position sites based off of that rather than just focusing in on a single unified number and saying, "Oh, we need 25 sites in Europe. We need 20 sites in the U.S.," kind of thing.

We are more focused on how do we make sure we get access to the patients, particularly with a rare disease like this, that allows us to ensure that we can get sufficient and consistent enrollment.

Jim Caruso: Yeah. That is a very fair response. Although it is not apples to apples, Kemp, our previous study, the phase IIb pivotal, had approximately 50 sites worldwide.

Kemp Dolliver: Great. Thanks very much.

Jim Caruso: Thank you, Kemp.

Operator: Thank you. If you do have a question, just press star one. At this time, there are no further questions. I would like to turn it back to the management team for closing remarks.

Jim Caruso: Terrific. Thank you, operator. Certainly thank you for everyone participating today, and Kevin and Kemp for those thought-provoking questions. This obviously concludes our call for the day. We thank you for your participation and hope that you have a really good day. Thanks.

Operator: Ladies and gentlemen, this does conclude your conference call for today. We thank you very much for your participation, and you may now disconnect. Have a great day, everyone.

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