Aptose Biosciences, Inc.

Good afternoon. My name is Buena and I will be your conference operator today. I would like to welcome everyone to the Aptos Biosciences conference call for a third quarter ended September 30th, 2021. At this time, all participants are in a listen-only mode. After the speaker's remarks, there will be a question and answer session. If you would like to ask a question during this time, simply press star followed by the number one on your telephone keypad. If you would like to withdraw a question, press the pan key. Thank you. As a reminder, this conference call may be recorded. I would like to introduce Ms. Susan Pietropalo.

Please go ahead. Thank you, Buena. Good afternoon, and welcome to the Aptos Biosciences Conference Call to discuss financial and operational results for the third quarter into September 30, 2021. Joining me on today's call are Dr. William G. Rice, Chairman, President, and CEO, Dr. Yodi Marango, Senior Vice President, Chief Financial Officer, and Chief Business Officer, and Dr. Rafael Behar, Senior Vice President, Chief Medical Officer. Before we proceed, I would like to remind everyone that certain statements made during this call will include forward-looking statements within the meaning of U.S. and Canadian securities laws. Forward-looking statements reflect Aptos' current expectations regarding future events but are not guarantees of performance, and it is possible that actual results and performance could differ materially from these stated expectations. They involve known and unknown risks, uncertainties, and assumptions that may cause actual results, performance, and achievement to differ materially from those expressed. To learn more about these risks and uncertainties, please read the risk factors set forth in Aptos' most recent annual report on Form 10-K and SEC and CEDAR filings. All forward-looking statements made during this call speak only as of the date they are made. Aptos undertakes no obligation to revise or update the statements to reflect events or circumstances after the date of this call, except as required by law. I will now turn the call over to Dr. Rice, Chairman, President, and CEO of Aptos Biosciences. Dr. Rice?

Thank you, Susan. I'd like to welcome everyone to our call for the third quarter ended September 30, 2021. Today, I want to spotlight the actions we've taken during the past quarter and over the entire year to build value on Aptos, a company focused on the effective treatment of hematologic malignancies and a company with expertise in kinase inhibitors and with an expanded team to develop them. This includes a look at our newest program, HM43239, or just 239, an oral, once daily, myeloid kinome inhibitor that already has delivered multiple complete responses in a broad spectrum of AML patients, and for which, just last week, we announced an exclusive global license agreement with the Honmy Pharmaceutical Company. We also will provide an update on Luteptinib, or just LUX, our oral, highly potent, non-covalent kinase inhibitor with dual activity as a myeloid kinome inhibitor and a lymphoid kinome inhibitor. And we will address what this latest transaction with 239 means for LUX. From an investment and catalyst thesis, 239 added a more advanced de-risk asset with proven clinical activity to our portfolio, a molecule that dramatically increases the probability of success for our therapeutic pipeline. And we believe this deal increases significantly the overall value of Aptos by any rational measure. 239 is not a sudden revelation to us. As a matter of course, in our proactive business development efforts and our heme focus, we continue to evaluate many compounds, even molecules at very early stages, as evidenced by our agreement with Crystal Neomics for LUX. We developed a relationship with the HONME team some time ago, and all the while we've been watching 239 and moving toward a partnership as the clinical validation data began to emerge over the past 12 months. Indeed, 239 entered the clinic for the treatment of AML patients a year earlier than did our other kinase inhibitor, LUX. And in that time, 239 has achieved multiple complete responses, or CRs, with a favorable safety profile. This is an effective and well-tolerated drug that already has changed the lives of critically ill AML patients harboring adverse mutation profiles that render them non-responsive to other drugs. So 239 fits exactly into the type of agent that defines our goals at Aptos. The timing of this deal was driven by the emerging clinical data with 239, as was illustrated in the ASH abstract released last week, and the emerging competitiveness for this program. And I want to recognize Dr. Morongo for orchestrating and negotiating the deal. We're thrilled to take the reins for the development of this clinically proven agent as an addition to our evolving pipeline, and to move it rapidly through the next steps of development. As a complementary addition to LUX, 239 strengthens Aptos' ability to treat a wider spectrum of AML patients. So how does this deal for 239 impact LUX? To be clear, 239 is an addition to our pipeline. It is not a replacement for LUX. LUX stands on its own merits, and we intend to develop LUX to its full capacity LUX is being tested in relapsed or refractory AML patients, where it already has achieved a complete response, and in highly relapsed or refractory B-cell malignancy patients, where we have begun to see consistent signs of anti-tumor activity. Some of you bluntly have asked, if we believe that LUX will be active in AML patients, then why did we enlicense 239? The short answer is, we want to own this therapeutic space, and adding 239 to our pipeline, along with LUX, is an important step toward that vision. The longer answer is it's because AML represents a collection of many forms of acute leukemia and not one single disease. Because AML is so mutationally diverse, no one agent can fully cover the range of all oncogenic drivers in all AML patients. And we're focused on treating the patients rather than merely treating a target. As we've said in the past, there's room for many agents in the treatment of AML. While some consider AML a disease driven by the FLT3 kinase, FLT3 is only one of the targets that you might want to cover in the disease. AML patients may have internal tandem duplication, tyrosine kinase domain, or gatekeeper mutations in FLT3, or no mutations at all in FLT3, or mutations in a multitude of other genes, including NPM1, TP53, IDH2, RAS, and many others. and each mutation or epigenetic alteration can program the cells to behave in a different manner. It therefore is essential to cover as many targets, albeit as safely as possible, and disrupt as many oncogenic pathways and escape routes as possible. Simply, not all genotypes of AML will be effectively targeted by any single drug. This is why we want LUX that covers FLT3 and a particular constellation of kinases operative in AML, And we want 239 that also covers FLT3, but then covers a different constellation of other kinases. We plan to develop each molecule, which can lead to a broader coverage of kinases and AML patient populations than any one drug. For any AML patient to achieve a complete response with a drug, that patient's disease must have a target profile that could be subjugated by the drug, and the drug must be administered at a level that suppresses those targets. With 239, those levels already have been achieved in multiple patients reported to date with complete responses. While we already have achieved therapeutically active levels with 239, LUX is earlier in development for AML, yet we already have reported one durable complete response with LUX in an AML patient. We continue to dose escalate LUX, now at 900 milligrams with our current formulation, to drive higher exposures, to suppress additional oncogenic driver kinases and effectively treat additional patients. In parallel to those dose escalations with the current formulation, we also are developing a new formulation for logs, referred to as Generation 3 or G3, that in animal studies can deliver 30-fold greater exposures per milligram of drug administered. The G3 capsules have been GMP manufactured, have passed stability tests, and we plan to introduce G3 into our ongoing clinical studies in 2022. We hope G3 will reduce significantly the pill burden and the amount of drug substance administered to patients, and this could be a meaningful step for LUX as we advance it through the clinic. While I've spoken about LUX being administered to AML patients, I'll remind you that LUX also is a lymphoid kinome inhibitor, and we're developing it for patients with B-cell lymphoid malignancies. where we continue to see anti-tumor activity and we will update you at ASH. So the progress we're observing with LUX in our ongoing clinical trials over and above other therapies that already have failed these very difficult to treat patient populations is encouraging and we are hopeful that LUX will prove to be valuable for a diversity of hematologic cancers. Before I hand the microphone to Dr. Behar, I want to bring the focus back to my original statements. We now have expanded our pipeline we have dramatically increased our potential for pipeline success by adding 239, while also maintaining a value stream and conviction to the development of LUX. Now I'll ask Dr. Behar, our Chief Medical Officer, to provide an overview of our clinical activities. Rath?