Good afternoon, everyone, and thank you for joining the H.C. Wainwright 2021 Virtual Global Life Sciences Conference. My name is Andres Maldonado, and I'm an associate here at H.C. Wainwright. While we are virtual this year, we are confident we're going to be able to provide value to you with over 425 companies presenting at the conference, as well as via your interactions through one-on-one meetings. H.C. Wainwright is a full-service investment bank dedicated to providing corporate finance, strategic advisory, and related services to public and private companies across a multitude of sectors and regions. We have a total of 18 publishing senior analysts with 493 companies across all sectors under our coverage. From a logistics standpoint, please make sure to reference your virtual conference online portal that provides your individual links to your meetings and all presentations.
Panels and all presentations are live and on-demand online, March 9th through the 10th. With that said, I'd like you to have a productive and enjoyable day, and I'd like to introduce our presenter, CEO of Keros Therapeutics, Jasbir Seehra. A company that specializes in the discovery, development, commercialization of novel treatments for patients suffering from hematologic and musculoskeletal disorders. Sir?
Thank you, Andres, and thanks to the organizers for giving us the opportunity to present. Let me start with the usual disclaimer regarding forward-looking statements that will be made in this presentation. Let me tell you about Keros. Keros is harnessing the powerful biology of the TGF-beta superfamily. We're a clinical stage biopharmaceutical company that's developing these novel therapeutics that target the TGF-beta superfamily. This approach has been validated with marketed products INFUSE for treatment of spinal fusion and Reblozyl for treatment of anemia in beta thalassemia and myelodysplastic syndrome. We're leveraging our extensive experience in the TGF-beta superfamily structure and function, and coupling that to our protein engineering experience to generate a pipeline of differentiated therapeutics. We're going to share with you three product candidates today.
KER-050 is designed to address ineffective hematopoiesis by modulating the TGF-beta superfamily, and is being developed to treat multiple cytopenias in patients with MDS and myelofibrosis. Our second product candidate is activin receptor-like kinase 2 inhibitor that is being developed for the treatment of anemia resulting from iron imbalance in patients including iron deficiency anemia patients and iron refractory iron deficiency anemia. This treatment can also be used potentially in patients that have a rare genetic disease called fibrodysplasia ossificans progressiva. The biology on iron imbalance is also the biology that you see in anemia of chronic inflammation. Therefore, we think KER-047 has the potential to treat a broad range of patients with this common underlying cause of iron imbalance. KER-012 is our preclinical candidate that is being developed for treatment of bone disorders as well as for pulmonary arterial hypertension.
Our differentiated pipeline in hematology and musculoskeletal is shown on this slide, where you can see that our KER-050 has completed its phase I study. We initiated the phase II trial in MDS in second half of 2020, and we'll be presenting the initial data from this study in mid 2021. We're also starting the phase II trial in myelofibrosis this year, and two trials with KER-047 in iron deficiency anemia as well as anemia from high hepcidin in IRIDA will start in the second half of the year. KER-012 will enter the clinic in the second half of the year. With that, let me move on to the most advanced program, KER-050, which is a novel treatment that addresses ineffective hematopoiesis in myelodysplastic syndromes as well as in myelofibrosis. Let me spend a few minutes talking about myelodysplastic syndromes.
This is a hematologic malignancy that affects elderly patients. As a consequence, these patients have multiple cytopenias. They have anemia, thrombocytopenia, and neutropenia, all due to ineffective hematopoiesis. Roughly 15,000- 20,000 patients with MDS are diagnosed each year in the U.S. and 90% of these patients are anemic, and a bout half of them have thrombocytopenia. There are no treatments for thrombocytopenia. All these patients can get are platelet transfusions. Anemia, there are treatments for anemia. They include red blood cell transfusions, erythropoiesis- stimulating agents or ESAs, and Reblozyl. ESAs only work at the early stages of red blood cell lineage. As a common stem cell in the bone marrow takes its journey to be a red blood cell, erythropoietins work at the earliest stages.
In MDS patients, it only works in patients with low transfusion burden and low endogenous levels of EPO. Reblozyl, which is approved for treatment of anemia in a subset of the MDS patients, those that have ring sideroblasts, iron deposits in the red blood cell precursors in the bone marrow. That represents roughly 15%-20% of all MDS patients. They have a defect in the terminal maturation of red blood cells. Cells that are late in this development to completing their journey to be a red blood cell. In phase III registration trial, it was shown that 38% of the RS patients responded to Reblozyl, compared to 13% with placebo. The benefit is similar to ESAs in low transfusion burden patients.
We believe that an agent, okay, that works throughout the erythropoiesis pathway, has the potential to treat all patients with MDS and be differentiated as a consequence. Let me share with you what KER-050 is. It's a modified activin receptor II fusion protein. Activin receptors are expressed on hematopoietic cells and modulate the differentiation of these precursor cells. KER-050 is a ligand trap composed of a modified extracellular domain fused to the Fc region of an IgG. As a consequence, a treatment with KER-050 increases red blood cells and platelets by inhibiting signaling through these, the ligands that act through these activin receptors. In preclinical studies, we demonstrated the increases in red blood cells arise by modulating the differentiations at multiple stages of erythropoiesis. We observed the similar changes in platelets, again, supporting action throughout the thrombopoiesis pathway.
Our phase I study recapitulated what was observed in preclinical studies. I'll share some of that data with you. In preclinical studies, what we observed is that a single treatment results in a rapid increase in red blood cells. In fact, you can see these increases occur as early as 12 hours, which really argues, okay, that these cells were almost at the end stage in terms of completing their journey to being a red blood cell. You see a sustained effect on erythropoiesis, throughout 14 days, which is consistent with acting at the earlier stages of erythropoiesis, where you initiate that cascade of events that allows these cells to continue their journey all the way to being a red blood cell. Interestingly, we also observed increases in erythropoietin, in circulation, about a two to three-fold increase in erythropoietin.
Therefore, KER-050 acts at all stages of erythropoiesis, including those at the earlier stage of erythropoiesis. We've completed our phase I study, like all phase I study, it was a safety study to look at safety, tolerability, and PK. We had multiple pharmacodynamic measures incorporated into a study to look for signals of activity. What we observed was that KER-050 drug levels were dose proportional, with a mean half-life of roughly 12 days. This half-life of 12 days, coupled with the pharmacodynamic effects observed in this study, have the potential for monthly or less frequent dosing with this therapeutic. We observed that the drug was well-tolerated to the highest dose level tested, which was 4.5 mg per kg.
The only notable adverse event in this study was reversible mild hypertension, and that was observed only in the subjects with roughly 3 g per dl increase in hemoglobin. Common to many agents that increase their red blood cells. Some of this data is shown on this slide, where we saw that from a single subcutaneous administration, you see rapid increases in red blood cells. This is reticulocyte, red blood cells, and hemoglobin. I'm only showing the hemoglobin panel here. This is consistent with accelerating the maturation of late-stage precursors. What we also observed was this sustained increase through day 29. Important to recognize that the drug levels reach a maximum on day four, and then after that, with a half-life of 12 days, the drug levels are declining in the course of 29 days. We see an increase.
This can only be achieved because we initiated a cascade of events whereby cells early on in their journey were started on their path to be a red blood cell. We believe, as a consequence of this, that KER-050 treatments will be infrequent. We also observed clinically meaningful increases in platelets. Here, we observed 20-30 times 10 to the nine changes in nine cells per liter increases in platelets, which are clinically meaningful because these are the increases that you're looking for when patients are at high risk of bleeding events. You're looking to see an increase with transfusions of 20-30 times 10 to the nine. Once again, what we see here is that we see a rapid increase in platelets and a sustained increase in platelets.
A mechanism that is mirroring what we observed in erythropoiesis. I already said that, what's on this slide, I'm not going to spend a lot of time on this, I think what KER-050 does is it works at all stages. That differentiates it, all stages of erythropoiesis, therefore, it differentiates it from agents that work at the early stages or at the terminal stages of red blood cell maturation. In addition, the platelet changes are also clinically meaningful for KER-050 to be differentiated from other agents that only affect red blood cells. With this, we have initiated our phase II trial in MDS patients. This is an open-label phase II trial in two parts, a dose escalation followed by a dose confirmation, where we're looking for changes in hematology parameters in patients with MDS. These are red blood cell parameters as well as in platelets.
In this study, patients will receive 12 weeks of treatment. That's four doses at 28-day interval, followed by a 12-week follow-up. Here we're evaluating all patients with MDS. In the dose escalation, what we're looking to see is, what are the doses at which RS patients respond and the non-ring sideroblast patients respond. We will take those doses into the dose confirmation part of the study, part two, where we'll increase the number of patients so that that study becomes the study that informs us about the design of our phase III registration trial. In part one, we have equal number of ring sideroblasts and non-ring sideroblasts patients in this study. KER-050 is also a potential treatment for ineffective erythropoiesis in myelofibrosis. Myelofibrosis is characterized by molecular abnormalities in the JAK/STAT pathway.
These molecular abnormalities result in expansion of red blood cell and platelet precursor, that results in ineffective erythropoiesis. It is the accumulation of these megakaryocyte precursors that break down, that results in inflammation in the bone marrow and subsequent bone marrow fibrosis and scarring. KER-050 increase both red blood cells and platelets by accelerating their development. We'll be starting a phase II study in myelofibrosis in 2021. We believe that KER-050 has the potential to correct this ineffective erythropoiesis, helping those precursors to advance to platelets and thereby reduce the breakdown of those platelet precursors, which results in the inflammation and fibrosis, therefore reducing the inflammation and fibrosis. In myelofibrosis, roughly 50% of the patients are anemic, and are transfusion dependent, and have thrombocytopenia. Furthermore, the current treatment, Jakafi, results in grade three for anemia, whereby the doses of Jakafi have to be adjusted.
Being able to correct both the anemia and the thrombocytopenia has a potential for this therapy. In the remaining time, I want to talk about the other two programs, KER-047, which is a treatment for anemias, iron deficiency anemia, IRIDA, as well as for FOP. It is a small molecule kinase inhibitor that targets ALK2. It is high potency with low nanomolar IC50s. It's highly selective over other kinases, but also within the TGF-beta superfamily, where it is selective against structurally similar receptors. The PK/ADME properties of the drug are suitable for once-a-day oral dosing. Let me tell you a little bit about ALK2 and its control of iron. ALK2 regulates hepcidin, which is the master regulator of iron homeostasis. It is ALK2 signaling that controls this hepcidin expression.
Excessive signaling through the ALK2 pathway results in high hepcidin, and this hepcidin results in iron being locked up in storage tissue and not being available for incorporation into red blood cells and resulting anemia. ALK2 signaling requires a number of components. It requires the ligands, the BMPs. It requires a co-receptor for the action of BMPs. It is a tightly regulated system with feedback loop whereby when hepcidin levels increase, it results in increased expression of a regulatory protease on the cell surface called MT2. This MT2 clears components of the signaling pathway, thereby reducing ALK2 signaling and hence reducing hepcidin. When there is loss of MT2 function, you get uncontrolled signaling through the ALK2 pathway with constitutively high levels of hepcidin. This is observed in a disease where genetic mutations in the MT2 gene lead to what is called iron refractory iron deficiency anemia.
This high hepcidin has also been observed in chronic inflammation, and where the high hepcidin can result in anemia in patients. We believe ALK2 signaling will normalize high hepcidin, and therefore ameliorate anemia. This can be seen in a mouse model, where when you take the gene that codes for MT2, if you now knock it out as we did in this study where upon administration of an siRNA that knocks down this gene in the liver, you get increases in hepcidin and you get a reduction in hemoglobin levels in the blood. You then treat with an ALK2 inhibitor, following treatment with the siRNA, you're able to reduce the hepcidin and correct the anemia in this mouse model. We believe that ALK2 inhibitors will have benefit in patients with high hepcidin. We completed our phase I study in healthy volunteers.
This was a study with single ascending dose as well as a multiple ascending dose. In this study, we were again looking for safety, tolerability, and PK, but we also again incorporated multiple pharmacodynamic markers that would give us signals of activity. In this study, what we observed was changes in these biomarkers. What we observed was that as a consequence of inhibition of ALK2, we do indeed observe the reduction in hepcidin. This reduction in hepcidin results in rapid and dose-dependent increases in serum iron and transferrin saturation. Furthermore, these increases in serum iron are available. This increase in serum iron is available for incorporation into red blood cells. The way we looked at it was to look at the hemoglobin content of the newly produced red blood cells, the reticulocytes, and we saw increases in those.
There were no serious adverse events reported in this trial, therefore, we're ready now to move this program into phase II study. Two studies, the iron deficiency anemia and iron refractory iron deficiency anemia, will give us proof of concept for treatment of anemia. These studies will start this year in 2021. This is also a treatment potentially for FOP. FOP is a rare genetic disease in which skeletal muscle and connective tissue transform into bone following injury. There are no cures or effective treatments for this devastating disease. Patients become confined to a wheelchair, then will have a life expectancy of roughly 40 years. It's caused by a single mutation in the ALK2 gene that result in a gain of function. This gain of function, when it's introduced into mice, you recapitulate every aspect of the disease.
Following injury, skeletal muscle in rodents carrying this mutation turns into bone, as shown here in green. In a dose-dependent manner, ALK2 is able to reduce the bone that it forms. We think this is a treatment for FOP as well. Finally, KER-012, our preclinical program for treatment of bone disorders and for pulmonary arterial hypertension. It is a proprietary selective activin receptor ligand trap that is in preclinical development for PAH and bone disorder. In our preclinical study, KER-012 has shown that it has high affinity and potently inhibits the ligands involved in regulation of bone homeostasis. Treatment with KER-012 increased bone mineral density, trabecular bone in both wild-type mice as well as those that had established osteoporosis.
Very important, this therapy does not increase red blood cell production in cynomolgus monkeys, which is one of the limitations of other programs where you see similar programs showing increases in bone mineral density but also have dose-limiting pharmacology on the red blood cell axis. We've taken this molecule into rat models of PAH and showed that in PAH models, we're able to prevent the right ventricle wall thickening that occurs as a consequence of PAH. In PAH, where you have hypoxia induced in that animal model, there is bone loss associated with that hypoxia, and we were able to prevent that bone loss as well. We believe that KER-012 has the potential to increase bone morphogenetic protein signaling by inhibiting the activin signal, and therefore is consequently a treatment for PAH where reduced BMP signaling is observed.
In summary, what I've shared with you is that Keros is positioned for clinical and commercial success. We're focused on developing novel therapies for TGF-beta superfamily, where the biology has been validated in the clinic. We have a pipeline that allows Keros to harness the potential of this TGF-beta superfamily with KER-050 in phase II studies, in MDS, and in myelofibrosis starting this year. KER-047 entering multiple phase II studies, and KER-012 entering the clinic later this year. Our discovery approach has the potential to identify additional molecules with differentiated profile that treat bone, muscle, and pulmonary disorders. Finally, these are the anticipated milestones in 2021, where KER-050, the initial data from that phase II trial that's ongoing, will be presented in the middle of this year, and additional updates will be available in the course of the year.
We'll be initiating the phase II trial in myelofibrosis with KER-050, with KER-047. Both studies start this year. KER-012, preclinical data will be presented at a major conference. The phase I study starting in the second half of 2021. With that, thank you for your time.
Thank you, Jasbir, for that very productive and informative presentation. We look forward to future updates from Keros. I'd like to take this time to thank you for the time and effort that went into preparing your presentation. Hopefully our next conference could be held in person rather than virtually. In the meantime, we're grateful for your flexibility and thank you for your presence this year. Thank you again.
Thank you as well.