On May 15, 2020 Jounce Therapeutics, Inc. (NASDAQ: JNCE), a clinical-stage company focused on the discovery and development of novel cancer immunotherapies and predictive biomarkers, reported two upcoming virtual poster presentations introducing the first preclinical data from the JTX-1811 program and data on the characterization of treatment emergent ICOS hi CD4 T cells with vopratelimab and their association with durable clinical responses. These posters will be presented at the American Association for Cancer Research (AACR) (Free AACR Whitepaper) Virtual Annual Meeting, being held June 22-24, 2020 (Press release, Jounce Therapeutics, MAY 15, 2020, View Source [SID1234558130]).

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Virtual Poster and Audio Presentation Details:

Title: Preclinical evaluation of JTX-1811, an anti-CCR8 antibody with enhanced ADCC activity, for preferential depletion of tumor-infiltrating regulatory T cells
Author and Audio Presenter: Fabien Dépis, Ph.D., Principal Scientist in Discovery at Jounce Therapeutics, Inc.
Poster Number: 4532
Session Title: Immunomodulatory Agents and Interventions
Date: Monday, June 22, 2020

Title: ICOS hi CD4 T cells emerging on vopratelimab treatment have Th1 central memory characteristics and may contribute to durability of clinical responses
Author and Audio Presenter: Amanda Hanson, B.A., Associate Scientist in Preclinical Sciences at Jounce Therapeutics, Inc.
Poster Number: 5536
Session Title: Immune Response to Therapies
Date: Monday, June 22, 2020

About JTX-1811
JTX-1811 is a monoclonal antibody designed to selectively deplete immuno-suppressive tumor-infiltrating T regulatory (TITR) cells. The target of JTX-1811 is CCR8, a chemokine receptor enriched on TITR cells. When JTX-1811 binds to CCR8, it targets TITR cells for depletion by enhanced antibody-dependent cellular cytotoxicity. Jounce expects to file an Investigational New Drug (IND) application in the first half of 2021.

About Vopratelimab
Jounce’s lead product candidate, vopratelimab, is a clinical-stage monoclonal antibody that binds to and activates ICOS, the Inducible T cell CO Stimulator, a protein on the surface of certain T cells found in many solid tumors. Vopratelimab was previously assessed in the Phase 1/2 ICONIC trial and was found to have an acceptable safety profile and be well-tolerated, alone and in combination with each of the anti-PD-1 antibodies nivolumab and pembrolizumab, and ipilimumab, an antibody that binds to CTLA-4. Vopratelimab is currently being assessed in the Phase 2 EMERGE clinical trial in a sequenced combination with ipilimumab in patients with non-small cell lung cancer (NSCLC) who have progressed on or after both a platinum-based regimen and a PD-1 or PD-L1 inhibitor. Jounce is also planning to initiate the Phase 2 SELECT clinical trial of vopratelimab with its investigational PD-1 inhibitor, JTX-4014, in TISvopra biomarker-selected patients who are PD-1 inhibitor naïve in second line NSCLC.

On May 15, 2020 Aprea Therapeutics, Inc. (Nasdaq: APRE), a biopharmaceutical company focused on developing and commercializing novel cancer therapeutics that reactivate mutant tumor suppressor protein, p53, reported financial results for the three months ended March 31, 2020 and provided a business update (Press release, Aprea, MAY 15, 2020, View Source [SID1234558129]).

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"Despite the challenges caused by the emerging COVID-19 pandemic, we continued to make significant progress to advance the development of our lead compound, eprenetapopt. In January 2020 we were granted Breakthrough Therapy Designation by the FDA to support our Phase 3 development program of eprenetapopt in combination with azacitidine," said Christian S. Schade, President and Chief Executive Officer of Aprea. "We are proud of the Aprea team, for their efforts to navigate through these uncharted times to support and advance our aggressive development of both eprenetapopt and our next generation p53 reactivator, APR-548, with minimal interruption."

Business Operations Update:

The Company is conducting, supporting and planning multiple clinical trials of eprenetapopt or APR-246:

·Pivotal Phase 3 MDS Trial—The Company is currently enrolling a pivotal Phase 3 randomized, controlled trial evaluating APR-246 with azacitidine as frontline therapy in HMA-naïve TP53 mutant myelodysplastic syndromes (MDS) patients with a primary endpoint of CR rate. Though the Company had initially observed a decrease in both patient screening and patient enrollment as a result of the coronavirus (COVID-19) pandemic, the Company has recently observed increased patient screening activity and has currently enrolled 140 patients in the trial with a number of additional patients now scheduled for screening. The Company currently plans to close enrollment of this trial in the second quarter of 2020 and remains confident it will have top-line data available by year-end 2020.

·Phase 2 MDS/AML Post-Transplant Trial—The Company is currently enrolling its single-arm, open-label Phase 2 trial evaluating APR-246 with azacitidine as post-transplant maintenance therapy in TP53 mutant MDS and acute myeloid leukemia (AML) patients who have received an allogeneic stem cell transplant. Though the Company had initially observed a decrease in both patient screening and patient enrollment as a result of the COVID-19 pandemic, the Company has recently observed increased patient screening activity and has currently enrolled 16 out of 31 patients in this trial with a number of additional patients scheduled for screening. The Company believes that it will complete enrollment in this trial in the third quarter of 2020.

·Phase 1 AML Trial—Based on in vitro data evidencing synergistic activity between APR-246 and venetoclax, the Company is conducting a Phase 1 clinical trial in frontline and relapsed/refractory TP53 mutant AML assessing APR-246 with venetoclax with or without azacitidine. The goals of the study include determining the safety, tolerability and preliminary efficacy of the combinations. The first patient was enrolled in 1Q 2020 and the Company completed enrollment of the first two safety cohorts of three patients each. Together with its investigators and clinical sites, the Company continues to assess the impact of the COVID-19 pandemic on the enrollment and the ability to maintain patients enrolled in this trial.

·Phase 1 NHL Trial—As further assessment of APR-246 in hematological malignancies, the Company has designed and plans to conduct a Phase 1 clinical trial in relapsed/refractory TP53 mutant chronic lymphoid leukemia (CLL) and mantle cell lymphoma (MCL) assessing APR-246 with venetoclax and rituximab, and APR-246 with ibrutinib. The Company is targeting the first patient to be enrolled in the second half of 2020.

·Phase 1/2 Solid Tumor Trial—Based on in vivo data evidencing synergistic activity between APR-246 and immuno-therapy agents including anti-PD-1 antibody, the Company has designed and plans to conduct Phase 1/2 clinical trials in relapsed/refractory gastric, bladder and non-small cell lung cancers assessing APR-246 with anti-PD-1 therapy. The Company is targeting the first patient to be enrolled in the second half of 2020.

·APR-548 — The Company’s second product candidate, APR-548, is a next-generation p53 reactivator with the potential for oral administration. APR-548 is a unique analog of APR-246 and therefore a pro-drug of MQ. APR-548 exhibits high oral bioavailability in preclinical testing and is being developed in an oral dosage form. The Company has completed Investigational New Drug, or IND, enabling preclinical studies of APR-548 and is targeting the submission of an IND in the first half of 2020.

First Quarter Financial Results

·Cash and cash equivalents: As of March 31, 2020, the Company had $122.5 million of cash and cash equivalents compared to $130.1 million of cash and cash equivalents as of December 31, 2019. The Company expects cash burn for 2020 to be between $35.0 million $40.0 million. The Company believes its cash and cash equivalents as of March 31, 2020 will be sufficient to meet its current projected operating requirements into 2023.

·Research and Development (R&D) expenses: R&D expenses were $9.1 million for the quarter ended March 31, 2020, compared to $3.7 million for the comparable period in 2019. The increase in R&D expenses was primarily related to the advancement of the Company’s lead product candidate, APR-246. In Q1 2019 the Company commenced a pivotal Phase 3 clinical trial of APR-246 with azacitidine for frontline treatment of TP53 mutant MDS which is supported by two ongoing Phase 1b/2 investigator initiated trials, one in the U.S. and one in France, testing APR-246 with azacitidine as frontline treatment in TP53 mutant MDS and AML patients. In addition, in Q1 2020, the Company began enrolling patients in a Phase 1 clinical trial in frontline and relapsed/refractory TP53 mutant AML assessing APR-246 with venetoclax with or without azacitidine.

·General and Administrative (G&A) expenses: G&A expenses were $2.8 million for the quarter ended March 31, 2020, compared to $0.7 million for the comparable period in 2019. The increase in G&A expenses was primarily due to increased insurance and professional fees associated with operating as a public company, as well as increased personnel costs.

·Net loss: Net loss was $9.4 million, or $0.45 per share for the quarter ended March 31, 2020, compared to a net loss of $3.5 million, or $2.97 per share for the quarter ended March 31, 2019. The Company had 21,054,842 shares of common stock outstanding as of March 31, 2020.

On May 15, 2020 Surface Oncology (Nasdaq: SURF), a clinical-stage immuno-oncology company developing next-generation immunotherapies that target the tumor microenvironment, reported five scientific posters sharing updated preclinical data at the American Association for Cancer Research (AACR) (Free AACR Whitepaper) 2020 Annual Meeting, to be held virtually on June 22-24 (Press release, Surface Oncology, MAY 15, 2020, View Source [SID1234558128]).

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The posters include preclinical data from Surface Oncology’s two lead clinical-stage antibody therapies: SRF617 (targeting CD39) and SRF388 (targeting IL-27). Three additional posters containing preclinical data from SRF813 (targeting CD112R) and SRF231 (targeting CD47) will also be presented.

Summaries are provided below; full posters will be placed on Surface Oncology’s website following the presentation.

Details of the AACR (Free AACR Whitepaper) presentations are as follows:

Presentation Type: e-poster (Abstract: 6639)
Title: SRF617, a potent enzymatic inhibitor of CD39, demonstrates single-agent activity and cooperates with various cancer therapies in both solid tumor and hematologic malignancies
Lead Author: Austin Dulak, Ph.D.
Date and Time: Monday, June 22nd, 9:00 a.m. EDT

Summary:

SRF617 is a potent inhibitor of CD39 enzymatic activity both in vitro and in vivo.
Inhibition of CD39 potentiates the activity of chemotherapy and immunotherapy agents to improve tumor growth inhibition and survival in mice.
Differential CD39 expression patterns across tumor types inform clinical indication selection.
These findings support future clinical studies of SRF617 as monotherapy and in combination with other therapeutic agents in treating patients with cancer.
Presentation Type: e-poster (Abstract: 4550)
Title: Increased IL-27 is associated with poor prognosis in renal cell carcinoma and supports use of SRF388, a first-in-class IL-27p28 blocking antibody, to counteract IL-27-mediated immunosuppression in this setting
Lead Author: Matthew Rausch, Ph.D.
Date and Time: Monday, June 22nd, 9:00 a.m. EDT

Summary:

IL-27 is a heterodimeric cytokine consisting of 2 subunits (IL-27p28 and Epstein-Barr virus induced gene 3 (EBI3)) that limits the intensity and duration of T cell-mediated immunity.
High levels of IL-27p28, EBI3, and IL27RA transcript levels are often elevated in renal cell carcinoma (RCC) tumors and are associated with poor clinical outcome.
SRF388 inhibits IL-27 signaling, diminishes inhibitory receptor expression and increases cytokine production. This pro-inflammatory response is enhanced when combined with PD-1 blockade.
Data from these studies indicate that blockade of IL-27 can potentiate anti-tumor responses by counteracting IL-27-mediated immune escape.
Presentation Type: e-poster (Abstract: 4548)
Title: SRF813, a fully human monoclonal antibody targeting the inhibitory receptor CD112R, enhances immune cell activation and anti-CD112R treatment in vivo demonstrates preclinical anti-tumor activity
Lead Author: Jim Mohan, Ph.D.
Date and Time: Monday, June 22nd, 9:00 a.m. EDT

Summary:

SRF813 inhibits the CD112-CD112R interaction and enhances NK cell activation.
CD112R inhibition in mouse tumor models reduced tumor growth and increased tumor-infiltrating lymphocyte activation.
The combination of anti-CD112R with PD-1 blockade leads to greater tumor growth inhibition than either treatment alone.
These preclinical data demonstrate that CD112R is a negative regulator of immune responses and that CD112R inhibition can potentiate anti-tumor responses in cancers that express CD112.
Presentation Type: e-poster (Abstract: 2196)
Title: SRF231, a fully human CD47 antibody, potentiates the effects of opsonizing antibodies and cytotoxic chemotherapies in preclinical cancer models
Lead Author: Marisa O. Peluso
Date and Time: Monday, June 22nd, 9:00 a.m. EDT

Summary:

SRF231 demonstrates anti-tumor activity as a monotherapy in multiple myeloma (MM) and non-small cell lung cancer (NSCLC) models.
SRF231 potentiates the effects of opsonizing antibodies (elotuzumab and daratumumab) in preclinical MM xenograft models.
SRF231 potentiates the effects of taxane and platinum-based standard of care chemotherapies in preclinical NSCLC xenograft models.
Presentation Type: e-poster (Abstract: 4515)
Title: The anti-CD47 antibody SRF231 increases anti-tumor activity of standard of care chemotherapy in platinum-resistant PDX models of ovarian cancer
Lead Author: Joyce Fu Liu, M.D.
Date and Time: Monday, June 22nd, 9:00 a.m. EDT

Summary:

Anti-CD47 directed therapy with SRF231 demonstrates the ability to significantly increase the anti-tumor activity of standard chemotherapies in xenograft and platinum-resistant patient-derived xenograft (PDX) models of ovarian cancer.
In 2018, Surface Oncology deprioritized the SRF231 clinical program and is concluding its Phase 1 study.

On May 15, 2020 Precision BioSciences, Inc. (Nasdaq: DTIL), a life sciences company dedicated to improving life through the application of its pioneering, proprietary ARCUS genome editing platform, reported financial results for the first quarter ended March 31, 2020, and provided a business update (Press release, Precision Biosciences, MAY 15, 2020, View Source [SID1234558127]).

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"So far in 2020, we have continued to make significant progress across our portfolio. This includes advancing the ongoing Phase 1/2a trial of our lead allogeneic CAR T program candidate, PBCAR0191, in relapsed/refractory (R/R) NHL and B-ALL; dosing the first patient in a Phase 1/2a trial of PBCAR20A in R/R NHL, CLL and SLL; and preparing to launch a Phase 1/2a clinical trial of our third allogenic CAR T candidate, PBCAR269A, in multiple myeloma," said Matt Kane, CEO and co-founder of Precision BioSciences. "Amid COVID-19’s impact on the healthcare ecosystem, we believe this progress is not only a testament to our team’s dedication, but also a reminder of the significant disease burden and poor prognosis faced by late-stage cancer patients who have failed previous treatment lines. As evidenced by early data from our Phase 1/2a trial of PBCAR0191, our differentiated, off-the-shelf CAR T approach may offer meaningful clinical benefit for these patients, while potentially avoiding safety and logistical challenges faced by other cell therapies, including autologous CAR T. We continue to look forward to reporting updated data from the PBCAR0191 program later in 2020."

Recent Developments and Upcoming Milestones:

Allogeneic CAR T Portfolio:

PBCAR0191: PBCAR0191 is an investigational allogeneic CAR T candidate targeting CD19, currently being evaluated in a Phase 1/2a study in relapsed or refractory (R/R) non-Hodgkin lymphoma (NHL) or R/R B-cell precursor acute lymphoblastic leukemia (B-ALL). The NHL cohort will include patients with mantle cell lymphoma (MCL), an aggressive subtype of NHL, for which Precision has received Orphan Drug Designation (ODD) from the U.S. Food and Drug Administration (FDA). In the first quarter of 2020, after discussion with the FDA, Precision implemented an amendment to the PBCAR0191 trial protocol designed to further optimize clinical activity. The amended trial design is intended to specifically address key clinical questions, which include assessing the impact of higher total doses of cells on clinical activity and/or the impact of modified lymphodepletion on the ability to achieve durable clinical benefit with

associated CAR T cell expansion and persistence. The PBCAR0191 clinical trial continues to progress, and no dose limiting toxicities or serious adverse events have been observed to date. Precision expects to present updated interim clinical data from both the NHL and B-ALL cohorts of this trial during 2020. PBCAR0191 is being developed in collaboration with Servier, an international pharmaceutical company.

PBCAR20A: PBCAR20A is a wholly-owned investigational allogeneic CAR T candidate targeting CD20 for the treatment of hematological malignancies. In April 2020, Precision dosed the first patient in its Phase 1/2a clinical trial evaluating PBCAR20A in two patient cohorts: R/R NHL, and R/R chronic lymphocytic leukemia (CLL) or R/R small lymphocytic lymphoma (SLL). Similar to the Phase 1/2a study of PBCAR0191, the NHL cohort for PBCAR20A will include patients with MCL, which has also received ODD from the FDA. Based on the safety profile observed from early dose levels in Precision’s ongoing Phase 1/2a study of PBCAR0191, the FDA authorized dosing in this Phase 1/2a study of PBCAR20A to begin at what was originally designed to be Dose Level 2 (1×106 cells/kg), with the subsequent dose level expected to be 3×106 cells/kg.

PBCAR269A: PBCAR269A is a wholly-owned investigational allogeneic CAR T candidate targeting B-cell maturation antigen (BCMA) for the treatment of R/R multiple myeloma, for which Precision has also received ODD. In January 2020, the FDA cleared Precision’s Investigational New Drug (IND) application for PBCAR269A, and the Company expects to begin dosing patients in a Phase 1/2a clinical trial in 2020.

In Vivo Gene Correction Portfolio:

PH1 Program: In January 2020, Precision announced that its first wholly-owned in vivo gene correction program will apply its ARCUS genome editing technology to knock out the HAO1 gene as a potential one-time treatment for primary hyperoxaluria type 1 (PH1), a rare genetic disease. In 2020, Precision expects to select a clinical candidate for this program to advance into human trials.

ASGCT 2020: At the American Society of Gene & Cell Therapy 23rd Annual Meeting held May 12-15, 2020, multiple presentations were made by Precision and its collaborators supporting the Company’s ARCUS genome editing platform and emerging pipeline applying this technology in vivo. Posters and talks included:

Engineering a Self-Inactivating Adeno-Associated Virus (AAV) Vector for ARCUS Nuclease Delivery (Abstract #654)

Gene Editing Approach to Eliminate Hepatitis B Virus Using ARCUS Meganucleases (Abstract #1057)

Therapeutic Efficacy of ARCUS Meganuclease Gene Editing – Arrest of Rod Degeneration and Restoration of Rod Function in a Transgenic Pig Model of Autosomal Dominant Retinitis Pigmentosa (Abstract #2)

Evaluation of the Long-term Effects of AAV-Meganuclease Genome Editing of PCSK9 in Macaque Liver (Abstract #518)

Corporate

COVID-19: In April 2020, Precision provided an update regarding its clinical trials and business operations amid the COVID-19 pandemic. This includes steps taken in line with guidance from public

health officials to protect the health and safety of its employees and to ensure continuity of its clinical trials. Precision’s work-from-home policy and restriction of on-site activities to certain manufacturing functions and limited laboratory and support activities remain in effect. To date, Precision has not experienced material delays to its planned or ongoing clinical trials.

Senior Leadership and Board Appointments: Precision further strengthened its senior leadership team with the appointment of Dora Alvarado as Senior Vice President, Human Resources. The Company also recently welcomed Geno Germano, President and CEO of Elucida Oncology, and former head of Pfizer’s Global Innovative Pharmaceutical business, to its Board of Directors.

Quarter Ended March 31, 2020 Financial Results

Cash and Cash Equivalents: As of March 31, 2020, Precision had approximately $154.2 million in cash and cash equivalents. The Company expects that existing cash and cash equivalents will be sufficient to fund operating expenses and capital expenditure requirements into the second half of 2021.

Revenues: Total revenues for the quarter ended March 31, 2020 were $7.0 million, compared to $5.5 million for the quarter ended March 31, 2019. This increase was due to increases in both Therapeutic and Food segments.

Research and Development Expenses: Research and development expenses were $24.9 million for the quarter ended March 31, 2020, as compared to $20.0 million for the same period in 2019. This increase of $4.9 million was primarily due to increases in direct research and development expenses, as well as platform development and early stage research expenses, including increases in personnel costs, laboratory supplies and services and expenses to support Precision’s technology platform development and manufacturing capabilities.

General and Administrative Expenses: General and administrative expenses were $9.6 million for the quarter ended March 31, 2020, as compared to $5.0 million for the same period in 2019. The increase of $4.6 million was primarily due to an increase in employee-related costs for additional personnel and facility costs associated with the Company’s growing infrastructure needs.

Net Loss: Net loss was $26.8 million, or $(0.52) per share, for the quarter ended March 31, 2020, compared to a net loss of $31.8 million, or $(1.99) per share, for the same period in 2019.

On May 15, 2020 Molecular Templates, Inc. (Nasdaq: MTEM, "Molecular Templates," or "MTEM"), a clinical-stage biopharmaceutical company focused on the discovery and development of the Company’s proprietary targeted biologic therapeutics, engineered toxin bodies (ETBs), reported that new preclinical data on its pipeline programs and technology platform will be presented at the AACR (Free AACR Whitepaper) Virtual Annual Meeting II to take place June 22-24, 2020 (Press release, Molecular Templates, MAY 15, 2020, View Source [SID1234558126]). All four posters are expected to be available on the AACR (Free AACR Whitepaper) website on June 22, 2020.

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Title: In Vivo Efficacy of a PD-L1 Targeted, Antigen Seeding Engineered Toxin Body
Authors: Hilario J. Ramos, Brigitte Brieschke, Sara LeMar, Joseph D. Dekker, Aimee Iberg, Garrett L. Robinson, Asis Sarkar, Banmeet Anand, Melissa M. Singh, Jay Zhao, Jack P. Higgins, Erin K. Willert. Molecular Templates Inc., Austin, TX
Session:Immunology: Therapeutic Antibodies 2
Abstract # 3366
MT-6402 is a highly differentiated approach to immuno-oncology. MT-6402 target PD-L1 and has been shown in preclinical studies to induce three unique biological effects:

Unlike current checkpoint inhibitors which bind PD-L1 and block interactions, MT-6402 directly destroys PD-L1+ tumor cells
MT-6402 can deliver foreign viral antigens into the target tumors to uniquely alter their immunophenotype to make them visible to CMV-reactive CD8+ T-cells
MT-6402 clears PD-L1+ immune cells and thereby potently activates the immune system
Non-human primate (NHP) data presented at the AACR (Free AACR Whitepaper) meeting show that MT-6402 mediated PD-L1+ immune cell clearance can elicit highly potent monotherapy immune activation in a way that has not been seen previously in NHP models with checkpoint inhibitors.

Title: CTLA-4 Targeted Engineered Toxin Bodies Designed to Deplete Regulatory T Cells (Tregs)
Authors: Aimee Iberg, Edith Acquaye-Seedah, Lilia A. Rabia, Garrett L. Robinson, Hilario J. Ramos, Joseph D. Dekker, Jay Zhao, Erin K. Willert. Molecular Templates Inc., Austin, TX
Session: Immunology: Therapeutic Antibodies 1
Abstract # 2278
Tumor resident regulatory T cells (Tregs) are important mediators of an immunosuppressive tumor microenvironment (TME) promoting tumor immune evasion. The presence of Tregs, and a higher ratio of Tregs to effector T cells in the TME, are associated with poor prognosis. There is concern that antibodies to CTLA-4 are not sufficiently effective at clearing Tregs from the TME. ETBs are being developed to specifically target CTLA-4+ Tregs and clear them from the TME. The clearance of Tregs in the TME is expected to re-expose the tumor to the immune system to allow for tumor control. Because CTLA-4-targeted ETBs preferentially affect Tregs versus CTLA-4+ CD8 T-cells, ETBs may also have a safer profile than CTLA-4 antibodies.

Title: Novel Engineered Toxin Bodies Targeting SLAMF7 (CS1)
Authors: Aimee Iberg, Garrett L. Cornelison, Caleigh Howard, Garrett L. Robinson, Jay Zhao, Hilario J. Ramos, Erin K. Willert. Molecular Templates Inc., Austin, TX
Session: Experimental and Molecular Therapeutics: Antibody Technologies
Abstract # 539
SLAMF7 (CS1) is a clinically validated target of monoclonal antibody therapy for the treatment of multiple myeloma. The approved antibody-based therapeutic, elotuzumab, works indirectly by recruiting effector cells to the tumor but does not show single agent clinical activity. ETBs have the potential to deplete malignant cells by means of potent and direct cell kill through enzymatic ribosomal destruction.

Title: CD45 Targeted Engineered Toxin Bodies Deplete Hematopoietic and Malignant Cells
Authors: Aimee Iberg, Garrett L. Robinson, Sara LeMar, Joseph D. Dekker, Jay Zhao, Hilario J. Ramos, Melissa M. Singh, Erin K. Willert. Molecular Templates Inc., Austin, TX
Session: Experimental and Molecular Therapeutics: Antibody Technologies
Abstract # 521
CD45, the leucocyte common antigen, is a haemopoietic cell-specific tyrosine phosphatase. Targeted and potent ETBs with intrinsically short half-lives are being developed to specifically destroy CD45 expressing cells including malignant cells of B, T and myeloid lineage. A single agent, targeted conditioning method for bone marrow transplant (BMT), employing ETBs, has the potential to increase patient safety and eliminate genotoxic effects that are associated with existing conditioning regimens.