Good afternoon, ladies and gentlemen. Welcome to Plus’ Call. Before we begin, we want to advise you that over the course of the call, including any question-and-answer session, forward-looking statements will be made regarding events, trends, business prospects and financial performance which may affect Plus Therapeutics’ future operating results and financial position. All such statements are subject to risks and uncertainties, including the risks and uncertainties described under the Risk Factors section included in Plus Therapeutics’ Annual Report on Form 10-K and quarterly reports on Form 10-Q filed with the Securities and Exchange Commission from time to time. Plus Therapeutics advises you to review these risk factors in considering such statements. Plus Therapeutics assumes no responsibility to update or revise any forward-looking statements to reflect events, trends or circumstances after the date they are made. It is now my pleasure to turn the floor over to Dr. Marc Hedrick, Plus Therapeutics President and Chief Executive Officer. Sir, you may begin.

Thank you, Cherie, and good afternoon, everyone. Thank you once again for taking the time to join us today as we provide an overview of recent business highlights and discuss our Second Quarter 2024 Financial Results. Joining me on the call today is Mr. Andrew Sims, our Chief Financial Officer. I'll begin the call by reviewing our recent clinical and corporate progress in the second quarter, then turn the call over to Andrew to review our financials, and then we'll both come back on for Q&A. So let me begin with updates from the 2024 Society for Neuro-Oncology and combined American Society for Clinical Oncology CNS Metastases Conference, which met last week in Denver. At SNO/ASCO, Plus was quite busy. We had four presentations, sponsored a symposium on novel emerging diagnostics and therapeutics for leptomeningeal metastases, and participated in a panel discussion on the opportunity for emerging therapies for brain metastases alongside senior executives from Novartis and Pfizer. Two of our four presentations warrant highlighting on our call this afternoon, and the full data from those presentations and from the symposium will be available soon on our website. First of all, Dr. Andrew Brenner, the ReSPECT-LM trial Principal Investigator, presented an interim update on the trial through Cohort 4, which included 16 patients. This is the most significant update that we provided since the SNO 2023 presentation. His presentation showed that through Cohort 4, an administered dose of 44 millicuries rhenium obisbemeda was safe and well tolerated with no dose-limiting toxicities, and the maximum tolerated dose had not been reached. Furthermore supporting the relative safety of the drug, thus far, the PK data demonstrated a high therapeutic window. Specifically, the mean absorbed radiation dose to the ventricles and cranial subarachnoid space was approximately 160 gray compared to only about 1 gray to the spleen. Also, a linear increase in absorbed dose to the regions of interest, specifically, the cranial subarachnoid space and cerebrospinal fluid, was noted from Cohort 1 with no increase noted in the spleen, which is the critical organ. In terms of response data, circulating tumor cell data was temporarily unavailable at that time, but it's now available, and we are back to using the test currently in Cohort 5. But recall that we observed a mean 53% reduction in circulating tumor cells in the cerebrospinal fluid for the first three treated cohorts. That was observed out to 28 days post-treatment, but the circulating tumor cells number came back up by 56 days post-treatment. Additional and significant response data through Cohort 5 is currently being reviewed and will be presented in detail at SNO in November, and I'll talk more about that in a moment. In terms of the median overall survival signal, again with 16 evaluable patients through Cohort 4, median overall survival was 12 months, with half the cohorts, that’s eight out of the 16 treated patients remaining alive at the time of analysis. This is an increase from that reported after Cohort 3 last November, which showed a median overall survival of 10 months. To put that data in perspective, leptomeningeal metastases is a devastating disease, as most of you know, from both a morbidity and mortality perspective, with typical survival rates ranging from two to six months after diagnosis, depending on primary tumor type. So this emerging efficacy signal, though early, is very encouraging compared to the standard of care. There was also a second presentation at SNO/ASCO where Dr. Priya Kumthekar reported the top line clinical results from our FORESEE trial. FORESEE evaluated the clinical utility of CNSide, our newly acquired novel CNS diagnostic, on leptomeningeal metastases treatment decision-making by physicians in 40 patients. The trial used a well-described design commonly used in the diagnostic space. Specifically, she reported that FORESEE met its primary endpoint with CNSide influencing treatment decisions in over 90% of clinical decision points evaluated, substantially exceeding the 20% level, which was the target for the primary endpoint to show effectiveness. Moreover, the study also showed that CNSide helped identify actionable mutations in the cerebrospinal fluid, such as HER2 amplification, that influenced 24% of therapeutic selection decisions, which is 14 out of 55 clinical decision points evaluated. Importantly, and related to the current state-of-the-art diagnostics found in major hospitals around the country, CNSide demonstrated more than twice the sensitivity in detecting tumor cells in the cerebrospinal fluid compared to the gold standard, which is cytology. Specifically, it showed a detection rate of tumor cells of 80% versus 29% for cytology. Also important, CNSide exhibited a very high specificity, as no tumor cells were detected in patients without leptomeningeal metastases. We were pleased to see this data formally presented, and these FORESEE results highlighted and validate our previous high conviction that CNSide, as both a diagnostic and therapeutic selection and monitoring tool, fulfills a critical clinical need in brain metastases that has now been shown to improve patient management, and we believe will lead to better patient outcomes in the near future. Finally, in addition to our presentations at SNO/ASCO, we also reported important data at the 2024 Society for Nuclear Medicine and Molecular Imaging, known as SNMMI, annual meeting in June 2024. The reported study used dosimetry data from the ReSPECT-LM clinical trial to evaluate the safety and potential for spinal cord toxicity of beta emitters or beta emission radioisotopes in the related physics and found that lower beta energy radionuclides, such as rhenium 186, largely spare the spinal cord versus other beta radionucleotides that we studied. These findings further support the thesis that rhenium 186 is an ideal radionuclide for CNS cancers, hitting the therapeutic window by delivering high therapeutic doses to the region of interest while minimizing toxicity. Now kind of moving on to our leptomeningeal program broadly speaking, first of all therapeutically, the current Phase 1 single administration ReSPECT-LM dose escalation trial will continue dosing until the next DSMB meeting, at which point we will determine if progressing to Cohort 6 is advisable. But thus far, as mentioned, a maximum tolerated dose has not been reached, despite delivering up to a maximum of 66 millicuries to the cerebrospinal fluid. In terms of upcoming data releases, a definitive trial update is planned for the Society for Neuro-Oncology 2024 that will be held in Houston this November. To-date, we have dosed a total of 25 patients and also treated a subset of patients with multiple doses of rhenium obisbemeda under compassionate use, and those patients have done really well. Also, the company has filed a new protocol under its open FDA IND to treat individual patients with a multiple dosing regimen. This submission follows a positive FDA Type C meeting in Q2. Once formally approved with final agreement from the FDA, the company will share the details of that trial protocol. That trial is anticipated to begin enrolling later in 2024 at the current seven trial sites, with a number of new sites to be added in the interim. The leptomeningeal program continues to be significantly supported by an approximately $18 million product development award from CPRIT, which covers approximately two-thirds of programmatic expenditures. Also, the company continues to be involved in active dialogue with CPRIT regarding program advancement and is actively seeking expanded opportunities for partnership with CPRIT that are mutually advantageous. In terms of our diagnostic LM program, we are in the process of expanding our CNSide diagnostic capabilities at a facility in Houston, Texas in specific, targeted, but strategic ways. First of all, we hired Dr. Greg Fuller, former Chief of Neuropathology at MD Anderson Cancer Center in Houston and an LM expert, to be the full-time Medical Director of the CNSide lab and oversee lab operations and also help support our LM therapeutic objectives. We have also improved the lab quality assurance systems in our capabilities to steadily increase testing capabilities as anticipated for growing research use both from Plus’ growing trial number in LM, but also from other trials that have contacted us with similar interest. In addition, we have applied for CLIA certification for CNSide as a laboratory-developed test, and approval under CLIA is anticipated later in 2024. We anticipate providing further business updates on the CNSide diagnostic program later this year as developments warrant. Now I’d like to shift gears to our ReSPECT-GBM trial. As most of you know, this trial evaluates a single dose of rhenium obisbemeda in patients with recurrent glioblastoma and is funded mostly through the NIH. We continue to enroll both Phase 2 patients with recurrent GBM, and that’s for tumors that are less than or equal to 20 cc, and also enrolling patients in our Phase 1 now at Cohort 8 for patients with larger tumors. We anticipate three new active GBM convection-enhanced delivery sites will be enrolling soon, and these should be able to transition to pivotal trial sites when the time warrants. Those sites include Ohio State University providing us a location in the Upper Midwest, and North Shore Hospital, part of the Northwell, Lenox Hill network in the greater New York region. We are also evaluating other additional sites with the intention of adding at least one location in the greater Southern California region. These sites, specifically OSU and North Shore Hospital, Lenox Hill, are on track to enroll patients in 2024. Additional sites beyond those mentioned are also being investigated for activation to support a potential pivotal trial. We are working to complete enrollment by the end of 2024, but it's more likely we will complete enrollment in the first half of 2025. A faster timeline will be influenced to a significant degree by participation from these new sites. Our plan is to provide a substantial update on the Phase 1 and Phase 2 data this fall at the CNS or Congress of Neurological Surgeons annual meeting, which is in late September, early October in Houston, Texas, and this will be our first opportunity to present this data to the neurosurgical community. In addition, I’d like to briefly update you on our pediatric brain cancer program. We previously announced that we received a U.S. Department of Defense award for $3 million to substantially support the Phase 1 trial for children with pediatric brain cancer, specifically pediatric high-grade glioma and ependymoma. That award is in the administrative phase and is anticipated to begin funding this September 2024. We are also on track to obtain IND approval for this trial, and Lurie Children’s Hospital will be the initial clinical trial site. Finally, we are making good progress behind the scenes on a number of important business items, specifically building in redundancy and commercial readiness in our supply chain and enhancing our drug delivery capabilities, and we plan to make material public updates on those in the near future. And with that, I’ll now turn the call over to our Chief Financial Officer, Mr. Andrew Sims, who will review the financials. Andrew?

Thank you, Marc. Good afternoon everyone. Please refer to our press release issued earlier today for a summary of our financial results for the second quarter ended June 30, 2024. The cash and investments balance was $8.4 million at June 30, 2024, compared to $8.6 million at December 31, 2023. The company recognized $2.9 million in grant revenue in the first half of 2024 compared to $2.3 million in the same period of 2023. This represents CPRIT’s share of the cost incurred for our rhenium obisbemeda development for the treatment of patients with leptomeningeal metastases. We expect 2024 grant revenue to be in the range of $6 million to $7 million. Total operating loss for the first half of 2024 was $7 million compared to $6.2 million in the same period of 2023. The increase is primarily due to increased spending related to the ReSPECT-LM trial. Net loss for the first half of 2024 was $6.2 million, or $1.15 per share versus $6.3 million or $2.06 per share for the same period of the prior year. An update on our runway cash position and guidance on our grant funding for the remainder of 2024. There are two additional sources of cash to which Plus has access beyond the balance disclosed in cash on hand and liquid investments on our Q2 2024 balance sheet. First, as a reminder, we announced in May that we closed a private placement financing of up to $19.25 million from new healthcare-focused institutional investors and company insiders, with a total of $7.25 million received at closing. In addition, there are up to $12 million of cash expected from the exercise of the one- and five-year warrants. As a side note, at June 30, 2024, the warrants issued as part of this private placement were recorded as a liability on the balance sheet, and as outlined in subsequent events, the warrant form was amended, eliminating the liability; henceforth these warrants will be accounted for under the equity accounting method. The second source of cash remains our anticipated ongoing funding through three awarded grants. First, the CPRIT grant to support the ReSPECT-LM trial. As reported, we received the first of two expected amounts from CPRIT in 2024, the first in Q2 of $3.3 million. We remain on track to receive the next advance from CPRIT of $3.7 million in mid to late Q4 2024. An additional $3.7 million is expected from CPRIT in 2025. Second, as reported on April 22, Plus has received an award recommendation from the U.S. Department of Defense for $3 million to support the upcoming ReSPECT-PBC in September 2024 and materially cover the cost of the planned Phase 1 trial. Funding is received annually in advance and covers a three-year period; approximately $1 million will be received under this grant in 2024. Third, Plus also continues to benefit from the NIH grant to support the ReSPECT-GBM Phase 1/2 trial. Although expected to be complete in 2024, it currently covers approximately 90% of the overall trial costs. We also continue to seek other non-dilutive sources of grant capital and have applied for approximately $13 million in additional grant funding year-to-date. We will continue to only report on individual grants when they are awarded. In summary, this provides incremental access to cash of $22 million: $10 million from CPRIT and DoD, and $12 million from the exercise of warrants from the May private placement.

Great. Thanks a lot, Andrew. Before we move to Q&A, just let me take a moment to provide some specific guidance for key events and milestones that we’re looking forward to through the remainder of 2024. As mentioned during the Congress of Neurological Surgeons, CNS, which is in late September and early October, Dr. John Floyd, who’s the Chief of Neurosurgery at UTHSCSA, University of Texas Health Science Center in San Antonio, will be presenting an update on the recurrent GBM Phase 1 and Phase 2 trial and most recent results. At the Society for Neuro-Oncology annual conference, which will be held in Houston, November 22 through 26 of this year, we’ll have three presentations. The first is a substantial update, as I mentioned earlier, on the ReSPECT-LM trial. Additionally, we have two CNSide diagnostic abstracts. The first is titled 'CSF Tumor Cell Detection, Quantification, and Biomarker Assessment, and How It Helps in the Clinical Management of Breast Cancer and Non-Small Cell Lung Cancer in Patients with Leptomeningeal Disease.' The second, which addresses a very important emerging issue of genetic drift in LM patients, is titled 'The Oncogenetic Flip in Patients with Leptomeningeal Metastases, Specifically the Longitudinal Detection in Cerebrospinal Fluid Tumor Cells Counts, and What It Reveals in Terms of Implications for the Differential Treatment of LMD Tumor.' All three will be presented at SNO this November. We also anticipate FDA approval on the ReSPECT-LM Phase 1 multiple-dose trial. The IND for the Phase 1/2 study of rhenium obisbemeda for pediatric ependymoma and high-grade glioma patients is anticipated also later this year. So with those updates, Cherie, I'll turn it back over to you for our Q&A session.

Thank you. Our first question will come from Justin Walsh with Jones Trading. Your line is open.

Hi, thanks for taking the question. I was wondering if you could provide some more context around the types of treatment decisions that are likely to be informed by CNSide. Obviously, therapy selection is one, but the 24% that informed therapy selection is lower than the 90% total decisions that were impacted?

Yes, it's a good question, Justin. So one of the key decisions is whether the patient has the disease or not. Having a highly sensitive test like the circulating tumor cells, as shown by the comparative data with cytology from the 4C trial, informs whether or not the patient requires treatment for leptomeningeal disease. There have been several reports where patients have indeterminate clinical signs, indeterminate imaging, or potentially supportive imaging consistent with leptomeningeal disease, but their spinal fluid is negative. So that’s probably the most important decision, frankly. Do they have the disease or not? With the combination of clinical evaluation, MRI, and CTCs in cytology, that decision can often be difficult to make. Generally, physicians seek two repeat CTC cell determinations before deciding if the patient does not have leptomeningeal disease and doesn't require treatment. That's one aspect. The second is an assessment of the genetic drift issue. We think that goes beyond just the HER2 issue into other actionable biomarkers that may dictate whether a certain type of drug or checkpoint inhibitor could be utilized in one tumor versus another. This genetic drift can go both ways, from positive to negative in the leptomeningeal space or the opposite. The third aspect involves the potential to stop treatment. For example, there are some case reports, although they are not significant series, showing that therapy can drive the number of circulating tumor cells down to zero. In those situations, stopping treatment and monitoring the patients that are doing well is a theoretical possibility, with reevaluation based on the ongoing CTC counts going forward. We are just beginning to explore what the data means, but there are at least three solid ways in which clinician decision-making can be impacted.

Got it. Thanks. Quick follow-up. It might be a little early, but I'm curious if you have any expectations with respect to timing once you get into the multi-dose LM portion of the trial?

Thank you, Justin. A couple of things: The IND is open. We are optimistic that what we've currently negotiated with the FDA will ultimately be approved, so we expect to hear back in less than 30 days. Assuming that goes well and we are already in discussions with sites, we are performing the activities required for site startup, including IRB review and budget approvals. However, because we already have an open IND that's similar, I think it should proceed relatively quickly. Our plan is to return to the current seven sites where we are working, and this process should be more efficient since we also have a number of leading sites ready to participate. I believe we can get the trial up and running later this year. Some sites will be ready before others. Regarding enrollment speed, the Phase 1 single administration was complicated by several factors, such as having a Part A and a Part B. The FDA wanted a clear stopping point, which led to some delays. Typically, we had to wait 90 days from the first patient treated and 30 days from the last patient before going back to the DSMB. This time around, we expect to accumulate data more quickly from the multiple doses without needing to go back to the FDA for feedback. I prefer to wait until we receive final feedback from the FDA, which we anticipate soon, before making any public announcements about timing.

Great. Thanks for taking the question.

Thanks, Justin.

Thank you. The next question will come from Sean Lee with H.C. Wainwright. Your line is open.

Good afternoon, guys, and congrats on the clinical progress this quarter. My first question is on the CNSide assay, so my understanding is that, correct me if I'm wrong, but all the tech transfer has been completed and you're now just setting up the test to be manufactured and marketed. I was wondering, what are the next steps you have to take before you can start selling the tests to the market, or at least to the clinical sites?

Hey, Sean, thanks for the question. Let me review where we are and the plan going forward. So we've acquired all the IP, hard assets, know-how, SOPs, and technology-related information, plus customer information. Remember, this test was commercial for a couple of years and was growing at a rate of about 30% year-over-year, with around 200 individual customers at the time it became unavailable before our acquisition. We transferred the technology back in Q1 of this year, got the test up and running, and have re-implemented it in our Cohort 5. We’re currently performing the test within our trial. In background, we have hired a Medical Director, and we are manufacturing some of the chips that the test is done on, specifically the microfluidic chips. We’ve overcome that as a critical supply element. Now it's really about scaling the test. We're well-positioned to accommodate testing needed for our multiple-dose trial, doing many more tests on patients longitudinally as they receive multiple doses. This requires a significant ramp-up in testing throughput, and we have the quality assurance measures in place. As I mentioned, Dr. Fuller is on board as the Medical Director. We are also conducting substantial commercial evaluation to ascertain the commercial opportunity's magnitude for this test and determine the required investment. The analysis looks positive so far, but before we commit further, we want to have a comprehensive and well-thought-out plan to execute. We will discuss more details on that relatively soon as we finalize our strategy.

Great. Thanks for that. My second question is on the LM studies. Now that you have a multi-dose study in the works, does it still make much sense to continue the single-dose study, especially with higher dose cohorts? Or would you be switching your focus mainly to the multi-dose study going forward?

It's a good question, and here's how I would respond to that. The FDA is very interested in determining a maximum tolerated dose in both our GBM trial and this LM trial. They have made that clear. Therefore, we are committed to understanding where the level of toxicity lies, and I think we are close. The safety signals in Cohort 5 lead me to believe we may be near the maximum tolerated dose, but we have not officially reached it yet. We'll continue that until we get to the stopping point or the maximum feasible dose. Secondly, we believe long-term, based on observations from the single administration trial, that a small group of patients receiving multiple doses are doing quite well. We think that to effectively treat this disease, multiple doses will be required. Thus, we wanted to initiate the multiple-dose trial quickly at our Cohort 2 dose. The data from the single administration has been promising, and we have presented that multiple times. Thus, I believe the next step is to review the Phase 1 data closely, evaluate the response data, discuss our findings with the FDA, get the multiple-dose study up and running, and then decide whether or not we want to take the single administration dose into a Phase 2/3 pivotal trial, as initially envisioned in our CPRIT Grant. This remains a viable option, and it may accelerate our timeline, but we could also wait for the data emerging from the multiple doses. If it seems safe and effective with a single administration, we will have to seriously consider our options regarding whether to move it to a pivotal trial. That will be an interesting discussion, but it will certainly be a good problem to have.

Thanks for that. That's very helpful. My last question is on the GBM study. I think in your prepared remarks, you mentioned that the grant for the GBM studies will be coming to an end towards the end of this year. I was wondering whether we can expect any more data updates from that later this year as well? Thanks.

Yes. Regarding the GBM trial, we will provide a meaningful update on Phase 1 and Phase 2 progress at the Congress for Neurosurgeons in late September and early October in Houston this year. The goal is to complete enrollment by the end of this year, although this may pose some challenges. We have two new sites in the final onboarding stages. If they contribute significantly, we might meet that deadline, but if not, we anticipate completing enrollment in the first half of next year. At that point, we will evaluate the data. We have continued to observe good safety signals and noteworthy efficacy signals compared to standard of care. Should these trends persist, we have a clear idea regarding what a pivotal trial design would look like based on our previous discussions with the FDA, which positions us well to move forward.

Great. That's all I have. Thanks again for taking my questions.

Thank you, Sean.

Thank you. Next, we will hear from Edward Woo with Ascendiant Capital. Your line is open.

Yes. Congratulations on all the progress, and congratulations on lining up additional potential grant funding. I was wondering, is there any seasonality to the grant funding? Are they issued all in certain times of the year? And have you noticed any change in the funding that's out there? Has it been more or less or been about the same? Thank you.

Hey, Ed. Yes, no, thanks for the question. It's definitely seasonal in this regard. For example, CPRIT typically has two times of the year when they accept grants, so the review process takes about six months. If you submit a proposal in July or August, it takes about six months to go through their review, receive a funding decision, and finalize the administrative award mechanics to get the funding disbursed. We experience something similar with the NIH, but it's more sporadic. They put out requests for proposals, specifically our DoD proposal, which was a more one-off situation. Therefore, we respond based on their granting calendar. We have developed a solid relationship with CPRIT. We've learned of other companies benefiting from multiple grants, with CPRIT willing to fund up to $20 million through Phase 2. Therefore, we've had a positive experience, and that capital has been crucial. We will continue to maintain close working relationships and explore more sporadic opportunities to utilize non-dilutive capital to minimize shareholder dilution. Thank you.

Thanks, Ed.

Thank you. I'm showing no further questions in the queue at this time. I would now like to turn the call back over to Dr. Marc Hedrick for any closing remarks.

Thank you, Cherie. We thank everyone, our analysts and shareholders and investors, for listening to this call. I also want to thank our patients, talking with two of them next week in Texas, who trust us to give them this investigational treatment. And thank you to all our employees who worked so hard to make it happen. We wish everyone a nice evening. Thank you.

This concludes today's program. Thank you all for participating. You may now disconnect.