Imago BioSciences’ Bomedemstat Demonstrates Continued Encouraging Clinical Activity in Phase 2 Data for Treatment of Essential Thrombocythemia and Myelofibrosis at EHA 2021 Virtual Congress

On June 11, 2021 Imago BioSciences, Inc. ("Imago"), a clinical stage biopharmaceutical company discovering new medicines for the treatment of myeloproliferative neoplasms (MPNs), reported that updates on two Phase 2 clinical trials of bomedemstat, one in patients with essential thrombocythemia (ET) and, the second in patients with advanced myelofibrosis (MF) (Press release, Imago BioSciences, JUN 11, 2021, View Source [SID1234583895]). The data were presented in two e-poster presentations during the 26th European Hematology Association (EHA) (Free EHA Whitepaper) Virtual Congress (EHA 2021), taking place June 9-17, 2021.

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Poster title: A Phase 2 Study of the LSD1 Inhibitor IMG-7289 (Bomedemstat) in Patients with Essential Thrombocythemia

The presented data show that bomedemstat was generally well-tolerated by patients with ET and demonstrated encouraging clinical activity as a monotherapy, showing symptomatic improvement in patients with significant MPN symptoms. Of the 12 patients dosed with bomedemstat for more than six weeks, 83% displayed substantial improvements in platelet count reduction, achieving platelets x109/L. Of the 10 patients entering the study with elevated white blood cell counts and evaluable at 12 weeks, 80% saw these counts fall within normal ranges. These improvements were achieved while maintaining stable hemoglobin levels. There were no dose limiting toxicities, no safety signals per Safety Advisory Board and one serious adverse event that was deemed unrelated.

"These encouraging data show that bomedemstat was well-tolerated and has the potential to bring meaningful clinical benefits for patients with essential thrombocythemia," said Wan-Jen Hong, M.D., chief medical officer of Imago BioSciences. "We are excited about these preliminary results from our lead asset, and look forward to completing enrollment of this study in order to lay the groundwork for a planned pivotal study in essential thrombocythemia."

Poster title: A Phase 2 Study of the LSD1 Inhibitor IMG-7289 (Bomedemstat) in Patients with Advanced Myelofibrosis

The presented data from an ongoing Phase 2 study indicated that bomedemstat as a monotherapy for patients with advanced MF offered a distinct clinical benefit profile, and was generally well-tolerated among participants. Of the 16 patients evaluable at 24 weeks, 94% showed improvements in total symptom scores (TSS), with a reduction of 50% or greater in almost a third of this subset. In an analysis of 34 patients evaluated for mutant allele frequencies (MAFs), MAFs decreased in 44% of patients and were stable in 47%, with no new mutations in up to 660 days of follow-up. Of the 18 patients evaluable for splenomegaly at 24 weeks, 89% had a reduction in spleen volume, with that of one patient decreasing by more than 35%. There were no dose limiting toxicities, no safety signals per Safety Advisory Board, and no progression to acute myeloid leukemia (AML).

"These updated clinical results reveal that bomedemstat continues to offer distinct clinical benefits for patients with advanced MF, showing overall improvement in total symptom scores, spleen volumes and anemia," said Wan-Jen Hong, M.D., chief medical officer of Imago BioSciences. "The study is now fully enrolled, so we look forward to sharing our cumulative data as we continue to advance this investigational program for patients who have few therapeutic alternatives."

Poster presentations are available on the EHA (Free EHA Whitepaper) Virtual Congress platform. The posters will also be available on the Imago website here.

Epigenomics AG plans to issue mandatory convertible bond in the amount of up to EUR 18.15 million

On June 11, 2021 The Executive Board of Epigenomics AG (Frankfurt Prime Standard: ECX, OTCQX: EPGNY; the "Company") reported that it has taken a decision in principle, with the approval of the Supervisory Board, to issue a subordinated mandatory convertible bond in an aggregate principal amount of up to EUR 18,150,000.00 (Press release, Epigenomics, JUN 11, 2021, View Source [SID1234583893]). This will be convertible into up to a total of 15,000,000 no-par value registered shares of the Company with a share of up to a total of EUR 15,000,000.00 in the share capital of the Company.

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The mandatory convertible bond will consist of up to 181,500 notes with a nominal amount of EUR 100.00 each, which will be offered for subscription by means of a rights offering initially to existing shareholders of Epigenomics AG. Shareholders will also be given the option of oversubscription. Furthermore, the Company plans to organize stock exchange trading of the subscription rights. The Company will shortly mandate an investment bank to accompany the issue and will start preparing a securities prospectus if legally necessary for the offering. The dates for the publication of a rights offering and the start of the subscription period will be published in due course.

In addition, today, Epigenomics AG has entered into a back-stop agreement with its shareholder Deutsche Balaton Aktiengesellschaft under which the latter has undertaken to acquire all notes in an aggregate principal amount of up to EUR 18,150,000.00 by exercising its subscription rights and by the acquisition of notes not subscribed via subscription rights and oversubscription rights. The obligation of Deutsche Balaton Aktiengesellschaft shall lapse in particular at the end of October 31, 2021, if the rights offering has not been published in the Federal Gazette by that date.

The notes will be non-interest-bearing (zero coupon) and have a term until 2027. In addition to conversion rights for the holders or creditors of the notes, they will also include a conversion obligation for all outstanding notes not yet converted at maturity.

Subject to any anti-dilution adjustments, the conversion price per share is EUR 1.21, i.e. each note with a nominal amount of EUR 100.00 will be convertible into 82 (eighty-two) no-par value registered shares representing EUR 1.00 per share of the Company’s share capital.

Epigenomics AG plans to use the proceeds from the convertible bond issue to finance its operations. Primarily, this is the completion of the development of the blood-based colorectal cancer screening test Epi proColon Next-Gen by conducting a clinical study in the U.S.A., which is required to obtain approval for the test by the U.S. Food and Drug Administration (FDA).

Curis Announces Positive Updated Data from Ongoing Phase 1/2 Study of CA-4948 Monotherapy in Patients with Relapsed or Refractory Acute Myeloid Leukemia and Myelodysplastic Syndromes

On June 11, 2021 Curis, Inc. (NASDAQ: CRIS), a biotechnology company focused on the development of innovative therapeutics for the treatment of cancer, reported updated data from its ongoing Phase 1/2 open-label, single arm, dose escalation and expansion trial of CA-4948, a novel, small molecule IRAK4 kinase inhibitor, in patients with acute myeloid leukemia (AML) or high-risk myelodysplastic syndromes (MDS) at the European Hematology Association (EHA) (Free EHA Whitepaper) 2021 Virtual Congress (EHA) (Free EHA Whitepaper) (Press release, Curis, JUN 11, 2021, View Source [SID1234583891]).

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"As we have observed increasingly mature sets of data, we continue to be pleased by the steady progression of clinical activity demonstrated by CA-4948 monotherapy in this historically difficult-to-treat late-line population," said James Dentzer, President and Chief Executive Officer of Curis. "We believe these updated data further support the growing body of evidence that CA-4948’s anti-cancer activity continues to deepen the longer patients remain on drug, which is enabled by its safety and durability profile to date. Further, after backfilling patient cohorts and evaluating additional data after the April 30, 2021 cut-off date for today’s presentation, we have concluded 300mg BID is the optimal dose to take into Phase 2 studies."

Mr. Dentzer added, "We are especially pleased with the outcomes seen to date for patients with spliceosome or FLT3 mutations. All three patients with a spliceosome mutation achieved an objective response. The FLT3 patient also achieved an objective response and, after two cycles of CA-4948, the patient’s FLT3 mutation was found to be completely eradicated. While these are early days, and we have a limited set of patient data, we are very encouraged about the potential CA-4948 may have to become a disease-modifying alternative for these late-line patients, where no approved therapies currently exist."

Mr. Dentzer continued, "In addition to the updated clinical data presented today, we are also excited by the preclinical combination synergy data announced, demonstrating that CA-4948 increases anti-cancer activity in AML cell lines resistant to clinically relevant concentrations of azacitidine and venetoclax, as well as synergistic antileukemic activity in combination with venetoclax and azacitidine. We look forward to initiating dosing in the Phase 1/2 combination study of CA-4948 plus azacitidine and CA-4948 plus venetoclax in patients with R/R AML and MDS later this year."

"As a clinician for patients with high-risk MDS or AML, I am acutely aware of the challenges of these diseases and the limitations of existing treatments. I continue to be very encouraged by the data coming out of this study," said Dr. Guillermo Garcia-Manero, Chief of the Section of Myelodysplastic Syndromes within the Department of Leukemia at The University of Texas MD Anderson Cancer Center and a lead investigator in the study. "This is a late-line population, in which patients have few options following repeated treatment failures and as a result, have deeply damaged and dysfunctional marrow, which severely limits their odds of hematologic recovery. Having an effective, non-myelosuppressive drug that does not further damage their already fragile marrow is of critical importance. The fact that some hematologic recovery has been observed and appears to continue while patients remain on therapy is an indication that CA-4948 may have the potential to provide, for the first time, a well-tolerated and clinically active treatment for this subset of heavily diseased patients."

The reported data are from Curis’s ongoing open-label, single arm Phase 1/2 dose escalation 3+3 study of orally administered CA-4948 monotherapy in adult patients with AML or high-risk MDS. A total of 22 patients (11 with high-risk MDS, 11 with AML) were enrolled across dose cohorts of 200 mg BID, 300 mg BID, 400 mg BID, and 500 mg BID. The primary objective of the study is to determine the maximum tolerated dose (MTD) and recommended Phase 2 dose (RP2D) for CA-4948 based on safety and tolerability, dose-limiting toxicities (DLT), and any biologic activity, pharmacokinetic (PK), and pharmacodynamic (PD) findings from the trial population. Additional objectives include characterization of CA-4948’s pharmacokinetic parameters and biomarker correlations.

Key findings from an oral presentation today at EHA (Free EHA Whitepaper) presented by Dr. Garcia-Manero from an April 30, 2021 cutoff in 17 evaluable patients (9 MDS and 8 AML), include:

Bone marrow blast reductions observed at all tested doses in 10 of 12 patients who were evaluable for bone marrow response (elevated blast count at baseline and at least one malignancy assessment following first cycle).
5 objective responses observed included:
1 patient experiencing a full hematologic recovery CR
1 patient with CRi with negative minimal residual disease
1 patient with partial response
2 patients with marrow CRs
3 patients had SF3B1 or U2AF1 spliceosome mutation and all 3 achieved marrow CR or better.
All patients with objective responses also saw signs of hematologic recovery.
Genomic analyses from multiple patients show disease modification by CA-4948:
DNA sequencing demonstrates disease modification with the reduction of cancer-associated variant allele frequency after CA-4948 treatment
RNA sequencing demonstrates disease modification with the reduction of long/short ratio of IRAK4 after CA-4948 treatment
No significant myeloid suppressive adverse events were observed.
Key findings from additional information included in today’s management’s KOL presentation:

An AML patient with spliceosome mutation SF3B1 who has experienced a durable objective response has been on study for over 8 months. In December 2020, this patient was reported as having a Marrow CR and has since improved to a CRi with negative minimal residual disease.
An AML patient with a FLT3 mutation, whose disease had relapsed after prior treatment with decitabine and venetoclax and was refractory to subsequent treatment with gilteritinib, experienced a partial response (90% decrease in marrow blast count, from 60% to 6%) as well as elimination of detectable FLT3 mutation based on genomic analysis post-treatment with CA-4948.
An AML patient with 4 prior lines of chemotherapy treatment showed reduction of IRAK4-L expression following CA-4948 treatment as well as a full recovery of hematologic parameters and has been on study for over 7 months.
Key findings in determining 300mg BID to be the Recommended Phase 2 Dose include:

Safety: No DLTs observed
PK/PD: PK exposure correlates with 98% target inhibition
Efficacy: 12 evaluable patients in the study had elevated blasts at baseline;
4 of these patients were dosed at 300mg BID;
All 4 patients achieved blast reductions, including CRi and negative MRD
Including additional patients enrolled after the April 30, 2021 cut-off at doses higher than the Recommended Phase 2 Dose, a total of 4 DLTs were observed:
400mg: 13% of patients experienced DLT (2 Grade 3 rhabdomyolysis)
500mg: 66% of patients experienced DLT (1 Grade 3 rhabdomyolysis and 1 Grade 3 syncope)
All three rhabdomyolysis cases were quickly detected by elevated CPK and resolved after dosing interruption; no cases involved renal dysfunction.
Key findings from a poster presentation today at EHA (Free EHA Whitepaper) of preclinical data in AML cell lines:

Combination with CA-4948 increased the antitumor effect of azacitidine
Combination with CA-4948 increased the antitumor effect of venetoclax
Combination with CA-4948 increased the antitumor effect of venetoclax + azacitidine
We believe synergistic activity observed in leukemia cells provides a rationale for clinical testing of CA-4948 + azacitidine, CA-4948 + venetoclax, and the triplet combination of all three agents together in patients with AML.
Webcast Event Information

Curis management will host a virtual KOL event today, June 11, 2021 at 8:00 am ET to discuss these results with Dr. Guillermo Garcia-Manero. To access the webcast, please visit the Events & Presentations section of the Curis website at www.curis.com.

About CA-4948

CA-4948 is an IRAK4 kinase inhibitor and IRAK4 plays an essential role in the toll-like receptor (TLR) and interleukin-1 receptor (IL-1R) signaling pathways, which are frequently dysregulated in patients with AML and MDS. Third parties have recently discovered that the long form of IRAK4 (IRAK4-L) is oncogenic and preferentially expressed in over half of patients with AML and MDS. The overexpression of IRAK4-L is believed to be driven by a variety of factors, including specific spliceosome mutations such as SF3B1 and U2AF1.

Constellation Pharmaceuticals Provides an Update from the Ongoing MANIFEST Study of Pelabresib

On June 11, 2021 Constellation Pharmaceuticals, Inc. (Nasdaq: CNST), a clinical-stage biopharmaceutical company using its expertise in epigenetics to discover and develop novel therapeutics, reported that three posters relating to the MANIFEST clinical trial of pelabresib (CPI-0610) in myelofibrosis (MF) were published online in association with the European Hematology Association (EHA) (Free EHA Whitepaper) annual meeting (Press release, Constellation Pharmaceuticals, JUN 11, 2021, View Source [SID1234583890]). The data in these posters are based on a data cutoff of September 29, 2020 from the MANIFEST Phase 2 clinical trial and reflect an analysis of pelabresib clinical and translational activity.

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"We are particularly enthusiastic about the publication of centrally reviewed translational data, which describe early improvements in bone marrow fibrosis in patients treated with pelabresib, and we believe these results support our thesis of disease-modifying treatment effects that go beyond symptom management," said Patrick Trojer, chief scientific officer of Constellation Pharmaceuticals. "We are currently enrolling patients in the Phase 3 pivotal study of MANIFEST-2 and our goal is to transform the standard of care for the treatment of myelofibrosis."

Data Highlights

Translational data, across all three arms of the Phase 2 MANIFEST study, support the disease-modifying potential of pelabresib

Centrally reviewed bone marrow fibrosis (BMF) pathology conducted in 63 patients showed similar improvements as reported previously for local review of BMF grade. 23 out of 63 patients (37%) achieved at least a 1 grade improvement in BMF. Of these patients, 83% achieved improvements in BMF by 24 weeks.
17% of the patients with BMF improvement (4 out of 23), improved by at least 2 grades.
31 out of 63 patients (49%) were stabilized or had no change, and only 4 out of 63 patients (6%) worsened.
An increase in BM erythroid progenitor cells and reduction of the number and cluster formation of megakaryocytes in the BM was observed in 59% and 65%, respectively, of 37 samples from patients treated with pelabresib either as a monotherapy or in combination with ruxolitinib.
Pelabresib durably reduced inflammatory cytokines such as tumor necrosis factor alpha (TNF alpha) and interleukin 18 (IL18) as early as 2 weeks and maintained through 24 weeks of treatment, based on an analysis of patient samples.
Arm 3 (1L) – CPI-0610 + ruxolitinib interim efficacy subgroup analysis in JAK-inhibitor-naïve patients

As previously reported at ASH (Free ASH Whitepaper) 2020, 42 of 63 evaluable patients (67%) achieved a ≥35% reduction in spleen volume (SVR35) at 24 weeks (the primary endpoint for Arm 3). 34 of 60 evaluable patients (57%) achieved a ≥50% reduction in Total Symptom Scores (TSS50) at 24 weeks.
Strong response was observed with pelabresib, irrespective of baseline risk status or demographic and disease characteristics.
Central pathology review of 27 1L patient bone marrow samples showed at least a one-grade improvement in bone marrow fibrosis in 9 out of 27 patients (33%); in all of these patients, improvement was observed within 6 months of starting treatment. 16 out of 27 patients (59%) showed stabilization of bone marrow fibrosis, while only 1 out of 27 patients (4%) showed worsening.
Arm 1 and 2 (2L) – Interim analysis demonstrating that pelabresib monotherapy in JAK-inhibitor-experienced or -ineligible patients, and with pelabresib + ruxolitinib in ruxolitinib-experienced patients, resulted in improvements in anemia

As previously reported at ASH (Free ASH Whitepaper) 2020, 3 of 14 evaluable Transfusion Dependent (TD) patients (21%) in Arm 1A achieved transfusion independence (the primary endpoint for arms 1A and 2A) and 13 of 36 evaluable TD patients (36%) in Arm 2A achieved transfusion independence.
9 out of 15 evaluable TD patients (60%) in Arm 1A, and 25 out of 47 of evaluable TD patients (53%) in Arm 2A achieved a ≥50% reduction in red blood cell transfusions.
Safety

As of the September 29, 2020 data cutoff, pelabresib was generally well tolerated in MANIFEST, both as monotherapy and in combination with ruxolitinib, and in both JAK-inhibitor-naïve and -ineligible as well as JAK-inhibitor-experienced patients.

Among the most common treatment-emergent adverse events (TEAEs) for CPI-0610 monotherapy in 46 safety-evaluable patients in Arm 1, those that were Grade 3 were thrombocytopenia (15%), anemia (13%), diarrhea (4%), constipation (2%), respiratory tract infection (2%), and weight decrease (2%). Amongst the most common TEAEs, there were no Grade 4. Other Grade 3/4 TEAEs (≥5%) include hyperuricemia (9%), hyperkalemia (7%) and dyspnea (7%). Nine patients discontinued treatment because of TEAEs. No Grade 5 events were observed.

Among the most common TEAEs in 78 safety-evaluable patients in Arm 2, those that were Grade 3 were thrombocytopenia (23%), anemia (10%), respiratory tract infections (5%), diarrhea (4%), asthenic conditions (4%), and nausea (3%). Amongst the most common TEAEs, Grade 4 events included thrombocytopenia (3%) and anemia (1%). Nine patients discontinued treatment due to TEAEs, including six Grade 5 TEAEs, which were acute kidney injury, traumatic subdural hematoma, brain stem hemorrhage (no concomitant thrombocytopenia), disease progression, congestive heart failure, and transformation to AML.

Among the most common TEAEs in 78 safety-evaluable patients in Arm 3, those that were Grade 3 were anemia (28%) and thrombocytopenia (5%). Amongst the most common TEAEs, Grade 4 events included thrombocytopenia (3%), anemia (1%), and respiratory tract infection (1%). Two patients discontinued treatment due to TEAEs. In addition, there were two Grade 5 TEAEs, each resulting from multi-organ failure due to sepsis.

EHA Poster Presentations

TITLE: Pelabresib (CPI-0610) improved anemia associated with myelofibrosis: interim results from MANIFEST Phase 2 study (Abstract Code: EP1077)

TITLE: Clinical benefit of pelabresib (CPI-0610) in combination with ruxolitinib in JAK-inhibitor treatment naïve myelofibrosis patients: Interim efficacy subgroup analysis from Arm 3 of MANIFEST Phase 2 study (Abstract Code: EP1085)

TITLE: BET inhibitor pelabresib decreases inflammatory cytokines, improves bone marrow fibrosis and function, and demonstrates clinical response irrespective of mutation status in myelofibrosis patients (Abstract Code: EP1080)

Date and Time: June 11, 9:00 AM CEST/ 3:00 AM EDT

About MANIFEST

MANIFEST is an open-label Phase 2 clinical trial of pelabresib (CPI-0610) in patients with myelofibrosis (MF), a rare cancer of the bone marrow that disrupts the body’s normal production of blood cells. Constellation is evaluating pelabresib in combination with ruxolitinib in JAK-inhibitor-naïve MF patients (Arm 3), with a primary endpoint of the proportion of patients with a ≥35% spleen volume reduction from baseline (SVR35) after 24 weeks of treatment. Constellation Pharmaceuticals is also evaluating pelabresib either as a monotherapy in patients who are resistant to, intolerant of, or ineligible for ruxolitinib and no longer on the drug (Arm 1), or as add-on therapy in combination with ruxolitinib in patients with a sub-optimal response to ruxolitinib or MF progression (Arm 2). Patients in Arms 1 and 2 are being stratified based on TD status. The primary endpoint for the patients in cohorts 1A and 2A, who were TD at baseline, is conversion to transfusion independence for 12 consecutive weeks. The primary endpoint for patients in cohorts 1B and 2B, who were not TD at baseline, is the proportion of patients with a ≥35% spleen volume reduction from baseline after 24 weeks of treatment.

Aptose Presents Highlights from EHA During Corporate Update Event

On June 11, 2021 Aptose Biosciences Inc. ("Aptose" or the "Company") (NASDAQ: APTO, TSX: APS), a clinical-stage company developing highly differentiated therapeutics that target the underlying mechanisms of cancer, reported that highlights from a corporate update event being held today, Friday, June 11, 2021, at 8:00 a.m. ET, in concurrence with participation at the EHA (Free EHA Whitepaper)2021 Virtual Congress (EHA) (Free EHA Whitepaper) (Press release, Aptose Biosciences, JUN 11, 2021, View Source [SID1234583888]). The event is focused on the current clinical status of luxeptinib, Aptose’s oral, first-in-class FLT3 and BTK kinase inhibitor currently in two Phase 1 a/b trials, one trial in patients with relapsed or refractory acute myeloid leukemia (AML), and the other trial in patients with relapsed or refractory B cell malignancies. The live and archived webcast of the presentation is available on Aptose’s website here.

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"Our recent clinical experience has confirmed that luxeptinib is an active drug in several indications across both myeloid and lymphoid malignancies, which is consistent with our hypotheses from our broad portfolio of preclinical work," said William G. Rice, Ph.D., Chairman, President and Chief Executive Officer. "We are especially encouraged to see this anti-tumor activity — including meaningful blast reductions — emerging even in heavily pretreated and clinically challenging patients, and we now look forward to continuing dosing at higher exposures for longer periods in order to explore fully the potential of this singular drug."

Aptose’s presentation provides a recap on luxeptinib, including the following key highlights:

Luxeptinib clinical program in AML

In the ongoing Phase 1a/b study in patients with relapsed or refractory AML, we completed the first two dose cohorts (450mg and 600mg) and have escalated to the third cohort (750mg). We plan to dose escalate further and have observed no safety trends likely to prevent continued escalation.
We achieved anticipated steady state PK levels and PD inhibition of target kinases, in line with our parallel study in different patient populations.
The first two dose cohorts delivered encouraging anti-leukemic activity in multiple patients, including a durable MRD-negative complete response in a FLT3-ITD AML patient who had relapsed after two allogeneic stem cell transplants, multiple lines of chemotherapy, and prior FLT3 inhibitor therapy.
Based on the totality of our preclinical and clinical observations to date, we expect to select an expansion dose and expansion cohort strategy for AML during 2H21 and aim to explore select disease genotypes under monotherapy and combination therapy programs.
Luxeptinib clinical program in B-cell malignancies

In the ongoing Phase 1a/b study in B-cell malignancies, intermediate dose levels to date have delivered all leading indicators of clinical activity, including target engagement with dose-dependent inhibition of phospho-BTK, treatment-related lymphocytosis in patients presenting with classic CLL, and tumor reductions across different B-cell malignancies (FL, CLL, SLL, WM).
We continue to observe cases of clear reversal of aggressively growing disease upon intra-patient dose-escalation and longer times on drug, suggesting that even aggressive disease may be successfully challenged with higher exposure levels and extended dosing duration of luxeptinib.
We currently are treating patients at 750mg BID, and we plan to continue further escalation to higher dose levels and for extended duration to tackle an increasingly treatment refractory presenting population.
We plan to continue exploring the spectrum of B-cell malignancies in line with the preliminary anti-tumor activity observed in the study to date.
In addition, clinical data for luxeptinib and APTO-253 were presented at EHA (Free EHA Whitepaper) this morning. The APTO-253 poster presentation contained a full update of the clinical status of APTO-253, a first-in-class small molecule MYC inhibitor in a Phase 1a/b trial in patients with relapsed or refractory AML or high-risk myelodysplastic syndrome (MDS). The posters are now available on the presentations page of Aptose’s website here.

Key highlights from the APTO-253 poster:

In the ongoing Phase 1a/b study in patients with relapsed or refractory AML and high-risk MDS, APTO-253 has been well-tolerated in the patients treated at 20, 40, 66, 100 and 150 mg/m2 over multiple cycles.
In the peripheral blood of patients, APTO-253 monomer rapidly transforms to and co-exists with the mechanistically active Fe(253)3 conjugate, and the serum levels of APTO-253 and the Fe(253)3 conjugate are dose proportional with significantly higher concentrations of Fe(253)3 conjugate that are sustained for longer periods of time compared to monomer, suggesting that further dose escalations may provide more sustained pressure on the MYC target gene and alter the biology of the tumor cells.
Collectively, the findings from the ongoing Phase 1a/b study support continued dose escalation of APTO-253. The study is current enrolling patients with AML and MDS at the sixth dose level of 210 mg/m2, and subsequent dose escalations are anticipated.