Greenwich LifeSciences Presents FLAMINGO-01 Phase III Trial Open Label Data Published at AACR Meeting 2026

On April 20, 2026 Greenwich LifeSciences, Inc. (Nasdaq: GLSI) (the "Company"), a clinical-stage biopharmaceutical company focused on its Phase III clinical trial, FLAMINGO-01, which is evaluating Fast Track designated GLSI-100, an immunotherapy to prevent breast cancer recurrences, reported the published abstract and poster from the AACR (Free AACR Whitepaper) Meeting 2026.

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The abstract is shown below and the poster being presented today can be seen and downloaded at the bottom of Phase III clinical trial tab on the Company’s website here.

This is the first abstract and poster presented jointly with the Steering Committee of FLAMINGO-01 with statistically significant delayed-type-hypersensitivity (DTH) immune response data, with subgroup analysis by the most prevalent HLA types.
In the non-HLA-A*02 open label arm where all patients (n=247) were treated with GLSI-100, immune responses to GP2 were measured at baseline and over time using skin tests and other methods. The other methods will be presented at a future conference.
A DTH reaction (redness and/or induration) was used to assess in vivo immune responses in patients. The DTH orthogonal mean was also measured 48-72 hours after injection but is not reported here.
In this preliminary data analysis, there was a significant increase in percentage of patients experiencing a DTH reaction (redness) in month 4 or month 6 compared to baseline. There were 191 patients with both baseline and month 4 or 6 assessments.
The frequency of DTH reactions increased by approximately 4x (290%) in the total open-label non-HLA-A*02 population, increasing from 5.2% of the patients experiencing a DTH reaction at baseline, prior to any GLSI-100 administration, to 20.4% of the patients experiencing a DTH reaction in month 4 or month 6 (McNemar, p < 0.001).
As reported in Table 1 of the poster, each HLA-A type exhibited more frequent immune reactivity after treatment with GLSI-100 than at baseline with frequency increasing from 100% to 700%.
Baseline DTH reaction prior to any treatment suggests that GP2 may be a natural antigen and that GP2 specific T cells may exist in some patients prior to any treatment with GLSI-100. Baseline immune response to GP2 prior to any vaccination with GP2 was also observed in the Phase IIb trial and is being observed in the blinded randomized arms of FLAMINGO-01, where HLA-A*02 only patients are being vaccinated.
Mechanism of Action: A positive immune response is an indicator that the immune system has been activated against recurring cancer cells, potentially leading to the prevention of metastatic breast cancer. The Company previously announced that in the non-HLA-A*02 arm, a preliminary analysis of recurrence rates after the Primary Immunization Series (PIS) is completed shows an approximately 70-80% reduction in recurrence rate. Thus, the immune response data is supporting the mechanism of action that reduces recurrences and prevents metastatic breast cancer.
This statistically significant non-HLA-A*02 open label arm immune response data is trending similarly to the immune response data in the HLA-A*02 patients in the Phase IIb study and the HLA-A*02 arms of FLAMINGO-01. The study is ongoing and data collection and cleaning continue, while some patients may still be in their PIS vaccination phase, so final results may vary.
A 1% per year recurrence rate is so low that the number of recurrence events is too few to correlate a negative or lack of immune response to recurrence. The same constraint existed with the Phase IIb data which has a similarly low recurrence rate per year. While DTH immune response may be valuable at an aggregate level looking at whole patient populations, the recurrence rate is too low to validate any immune response measure as a biomarker for individual patient treatment decisions. It is also likely that some responding patients may not exhibit any immune response but still could be protected by GLSI-100 vaccination, thus helping to preserve the blind on the randomized arms of FLAMINGO-01.

The immune response abstract and poster conclusion: The statistically significant increase in the incidence of DTH reactions over time found in this preliminary analysis of GLSI-100 treated non-HLA-A*02 patients shows that GLSI-100 treatment should not be limited to HLA-A*02 patients. Patients treated with GLSI-100 were increasingly able to mount an immune response to GP2 as evidenced in this preliminary data. Future investigations may explore the use of immune responses to assess correlation of DTH to ISRs, immunogenicity of GLSI-100 by specific HLA type, timing of boosters to sustain immunity, clinical site performance, and the discontinuation of treatment for non-responders.

In addition, the second poster describing the Phase III trial design, which is being presented on Tuesday, April 21, can be downloaded and seen on the website using the same link. This poster provides an update that over 1,300 patients have been screened to date in FLAMINGO-01. The new protocol amendment, which is still under regulatory review in certain countries, is not discussed.

CEO Snehal Patel commented, "This new immune response data further supports the combination of HLA-A*02 and non-HLA-A*02 patients in the same randomized arms. In the US, the FDA recently reviewed such protocol changes and the many non-HLA-A*02 patients on waiting lists that were previously screened are now being enrolled. The screen rate continues to be encouraging, reflecting the high patient interest in the study as we have now screened over 1,300 patients. The Company will have the option to pursue approval for both HLA-A*02 and non-HLA-A*02 patients together using the increased statistical power of a combined analysis of the two patient groups or to pursue subgroups based on planned multiple interim analyses."

The abstract from today’s immune response data and the members of the Steering Committee follow:

Abstract Number: CT138 – Poster Section 52 on April 20, 2026, 2-5pm PT

Abstract Title: Preliminary delayed-type-hypersensitivity immune response results from open-label arm of on-going Phase III study to evaluate the efficacy and safety of GLSI-100 (GP2 + GM-CSF) in breast cancer patients with residual disease or high-risk PCR after both neo-adjuvant and postoperative adjuvant anti-HER2 therapy, Flamingo-01

Snehal S. Patel1, Jaye Thompson1, F. Joseph Daugherty1, Francois-Clement Bidard2, William J. Gradishar3, Marcus Schmidt4, Miguel Martin5, Joyce A. O’Shaughnessy6, Hope S. Rugo7, Cesar A. Santa-Maria8, Laura M. Spring9, Mothaffar F. Rimawi10

1Greenwich LifeSciences, Stafford, TX,2Institut Curie, Paris, France,3Northwestern University, Chicago, IL,4University Medical Center Mainz, Mainz, Germany,5GEICAM, Madrid, Spain,6Sarah Cannon Research Institute, Dallas, TX,7City of Hope Comprehensive Cancer Center, Duarte, CA,8Johns Hopkins University, Baltimore, MD,9Massachusetts General Hospital, Boston, MA,10Lester and Sue Smith Breast Center, Dan L Duncan Comprehensive Cancer Center, Baylor College of Medicine, Houston, TX

Background: This Phase III trial is a prospective, randomized, double-blinded, multi-center study (NCT05232916) in HLA-A*02 patients at approximately 140 sites in the US and Europe. A third non-randomized arm of approximately 250 non-HLA-A*02 patients is now fully enrolled and preliminary immune response data is presented below. GP2 is a biologic nine amino acid peptide of the HER2/neu protein delivered in combination with Granulocyte-Macrophage Colony Stimulating Factor (GM-CSF) that stimulates an immune response targeting HER2/neu expressing cancers, the combination known as GLSI-100.

Methods: After standard of care neoadjuvant and adjuvant therapy, 6 intradermal injections of GLSI-100 will be administered over the first 6 months and 5 subsequent boosters will be administered over the next 2.5 years. The participant duration of the trial will be 3 years treatment plus 1 additional year follow-up. Immune responses to GP2 were measured over time using delayed-type-hypersensitivity (DTH) skin tests and injection site reactions (ISRs). The patient population is defined by these key eligibility criteria: 1) HER2/neu positive and HLA, 2) Residual disease or High risk pCR (Stage III at presentation) post neo-adjuvant therapy, 3) Exclude Stage IV, and 4) Completed at least 90% of planned trastuzumab-based therapy.

Results: All patients (n=247) were vaccinated with GLSI-100 and continue in treatment and follow-up. A DTH reaction (redness) was used to assess in vivo immune responses in patients. The DTH orthogonal mean was measured 48-72 hours after injection. In this preliminary data analysis, there was a significant increase in percentage of subjects experiencing a DTH reaction in month 4 or month 6 compared to baseline. The frequency of DTH reactions increased by approximately 4x from 5.2% of the patients experiencing a DTH reaction at baseline, prior to any GLSI-100 administration, to 20.4% of the patients experiencing a DTH reaction in month 4 or month 6 (McNemar, p < 0.001). The study is ongoing and data collection and cleaning continue so final results may vary.

Conclusions: The increase in the incidence of DTH reactions over time found in this preliminary analysis of GLSI-100 treated non-HLA-A*02 patients shows that GLSI-100 treatment should not be limited to the HLA-A*02 genotype. Subjects treated with GLSI-100 were increasingly able to mount an immune response to GP2 as evidenced in this preliminary data. Future investigations may explore the use of immune responses to assess: correlation of DTH to ISRs, immunogenicity of GLSI-100 by specific HLA type, timing of boosters to sustain immunity, clinical site performance, and the discontinuation of treatment for non-responders.

The Steering Committee authoring abstract CT138 is comprised of the following experts in the field of breast cancer oncology representing prominent teaching hospitals in the US and 4 of the largest breast oncology networks in the US, Germany, France, and Spain:

Dr. Mothaffar F. Rimawi – Professor of Medicine at the Baylor College of Medicine and Executive Medical Director and Co-Leader, Breast Cancer Program of the Dan L Duncan Comprehensive Cancer Center
Dr. Francois-Clement Bidard – Professor of Medical Oncology, UVSQ/Paris Saclay University, Head of Breast Cancer Group, Institut Curie, Vice-Chair of the French Breast Cancer research group UCBG (Unicancer)
Dr. William J. Gradishar – Professor of Medicine at the Feinberg School of Medicine at Northwestern University, Chief of Hematology and Oncology in the Department of Medicine, and Betsy Bramsen Professor of Breast Oncology
Dr. Sibylle Loibl – Professor (apl) Goethe University Frankfurt/M, Clinical Consultant Centre for Haematology and Oncology/Bethanien Frankfurt/M, CEO of GBG Forschungs GmbH & Chair of the German Breast Group (GBG)
Dr. Miguel Martin – Professor of Medicine, Head, Medical Oncology Service, Gregorio Marañón General University Hospital, Complutense University, Madrid, CEO of GEICAM
Dr. Joyce A. O’Shaughnessy – Celebrating Women Chair in Breast Cancer, Baylor University Medical Center and Chair, Breast Cancer Program, Texas Oncology, US Oncology, Dallas, Texas
Dr. Hope S. Rugo – Director, Women’s Cancers Program, Division Chief, Breast Medical Oncology, Professor, Department of Medical Oncology & Therapeutics Research, City of Hope Comprehensive Cancer Center, Professor Emeritus, University of California, San Francisco
Dr. Cesar A. Santa-Maria – Associate Professor of Oncology, Breast and Gynecological Malignancies Group, Director of Breast Cancer Trials, Johns Hopkins Sidney Kimmel Comprehensive Cancer Center
Dr. Laura M. Spring – Assistant Professor, Medicine, Harvard Medical School, Attending Physician, Medical Oncology, Massachusetts General Hospital
About the AACR (Free AACR Whitepaper) Annual Meeting 2026

The AACR (Free AACR Whitepaper) is the first and largest cancer research organization dedicated to accelerating the conquest of cancer and has more than 61,000 members residing in 143 countries and territories. The AACR (Free AACR Whitepaper) Annual Meeting is the focal point of the cancer research community, where scientists, clinicians, other health care professionals, survivors, patients, and advocates gather to share the latest advances in cancer science and medicine. From population science and prevention; to cancer biology, translational, and clinical studies; to survivorship and advocacy; the AACR (Free AACR Whitepaper) Annual Meeting highlights the work of the best minds in cancer research from institutions all over the world.

About FLAMINGO-01 Open Label Phase III Data
More than 1,000 patients have been screened with a current screen rate of approximately 800 patients per year. The 250 patient non-HLA-A*02 arm is now fully enrolled, where all patients received GLSI-100, which is 5 times more treated patients and recurrence rate data than the approximately 50 patients treated in the Phase IIb trial. The Primary Immunization Series (PIS), which includes the first 6 GLSI-100 injections over the first 6 months and is required to reach peak protection, is followed by 5 booster injections given every 6 months to prolong the immune response, thereby providing longer-term protection.

In the non-HLA-A*02 arm, a preliminary analysis of recurrence rates after the PIS is completed shows an approximately 70-80% reduction in recurrence rate.
This observation is trending similarly to the Phase IIb trial results and hazard ratio where HLA-A*02 patients were treated and where breast cancer recurrences were reduced up to 80% compared to a 20-50% reduction in recurrence rate by other approved products.
The immune response at baseline prior to any GLSI-100 treatment, the increasing immune response during the PIS, and the safety profile of non-HLA-A*02 patients is trending similarly to the HLA-A*02 arms of FLAMINGO-01 and to the Phase IIb study.

Analysis of the open label data from FLAMINGO-01 has been conducted in a manner that maintains the study blind. The open label recurrence rate, immune response, and safety data is based on the patients enrolled to date in FLAMINGO-01 and the data provided by the clinical sites so far, which is not completed or fully reviewed, and is thus preliminary. While comparing any preliminary FLAMINGO-01 data to the Phase IIb clinical trial data may be possible, these preliminary results are not a prediction of future results, and the results at the end of the study may differ.

About GLSI-100 Phase IIb Study

In the prospective, randomized, single-blinded, placebo-controlled, multi-center (16 sites led by MD Anderson Cancer Center) Phase IIb clinical trial of HLA-A*02 breast cancer patients, 46 HER2/neu 3+ over-expressor patients were treated with GLSI-100, and 50 placebo patients were treated with GM-CSF alone. After 5 years of follow-up, there was an 80% or greater reduction in cancer recurrences in the HER2/neu 3+ patients who were treated with GLSI-100, followed, and remained disease free over the first 6 months, which we believe is the time required to reach peak immunity and thus maximum efficacy and protection. The Phase IIb results can be summarized as follows:

80% or greater reduction in metastatic breast cancer recurrence rate over 5 years of follow-up with a peak immune response at 6 months and well-tolerated safety profile.
The PIS elicited a potent immune response as measured by local skin tests and immunological assays.
About FLAMINGO-01 and GLSI-100

FLAMINGO-01 (NCT05232916) is a Phase III clinical trial designed to evaluate the safety and efficacy of Fast Track designated GLSI-100 (GP2 + GM-CSF) in HER2 positive breast cancer patients who had residual disease or high-risk pathologic complete response at surgery and who have completed both neoadjuvant and postoperative adjuvant trastuzumab based treatment. The trial is led by Baylor College of Medicine and currently includes US and European clinical sites from university-based hospitals and academic and cooperative networks with plans to open up to 150 sites globally. In the double-blinded arms of the Phase III trial, approximately 500 HLA-A*02 patients are planned to be randomized to GLSI-100 or placebo, and up to 250 patients of other HLA types are planned to be treated with GLSI-100 in a third arm. The trial has been designed to detect a hazard ratio of 0.3 in invasive breast cancer-free survival, where 28 events will be required. An interim analysis for superiority and futility will be conducted when at least half of those events, 14, have occurred. This sample size provides 80% power if the annual rate of events in placebo-treated subjects is 2.4% or greater.

For more information on FLAMINGO-01, please visit the Company’s website here and clinicaltrials.gov here. Contact information and an interactive map of the majority of participating clinical sites can be viewed under the "Contacts and Locations" section. Please note that the interactive map is not viewable on mobile screens. Related questions and participation interest can be emailed to: [email protected]

About Breast Cancer and HER2/neu Positivity

One in eight U.S. women will develop invasive breast cancer over her lifetime, with approximately 300,000 new breast cancer patients and 4 million breast cancer survivors. HER2 (human epidermal growth factor receptor 2) protein is a cell surface receptor protein that is expressed in a variety of common cancers, including in 75% of breast cancers at low (1+), intermediate (2+), and high (3+ or over-expressor) levels.

(Press release, Greenwich LifeSciences, APR 20, 2026, View Source [SID1234664540])

Blenrep (belantamab mafodotin) approved in China for treatment of 2L+ relapsed/refractory multiple myeloma

On April 20, 2026 GSK plc (LSE/NYSE: GSK) reported the National Medical Products Administration (NMPA) of China has approved Blenrep (belantamab mafodotin) in combination with bortezomib and dexamethasone (BVd) for the treatment of adults with relapsed or refractory multiple myeloma who have received at least one prior line of therapy. The approval follows priority review5 of the application and Breakthrough Therapy Designation6 for the BVd combination based on its potential to provide substantial improvement over available therapies.7

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The Blenrep approval is supported by data from the pivotal DREAMM-7 phase III trial. These include statistically significant and clinically meaningful progression-free survival (PFS) and overall survival (OS) results for the Blenrep combination versus a daratumumab-based triplet combination with bortezomib and dexamethasone (DVd). The safety and tolerability profiles of the Blenrep combination were broadly consistent with the known profiles of the individual agents.1,2

Hesham Abdullah, Senior Vice President, Global Head Oncology, R&D, GSK, said: "Patients with multiple myeloma who face relapse need treatment options that are both effective and accessible. Today’s approval of Blenrep brings anti-BCMA therapy to patients in China with relapsed or refractory multiple myeloma in 2L+, introducing a differentiated mechanism of action with the potential to help slow disease progression and extend survival. Further, Blenrep as the only anti-BCMA ADC is fully outpatient administered, so patients can be treated at any site of care without complex pre-administration regimens or hospitalisation."

In China, the incidence of multiple myeloma has doubled to approximately 30,000 new cases annually and mortality has increased by 50% over the past three decades.8 Blenrep is the only anti-BCMA (B-cell maturation antigen) antibody-drug conjugate (ADC) approved in multiple myeloma, which provides patients with a differentiated mechanism of action. Blenrep can be administered to a range of patient types across treatment settings as a 30-minute outpatient infusion.

About multiple myeloma
Multiple myeloma is the third most common blood cancer globally and is generally considered treatable but not curable.9,10 There are approximately 180,000 new cases of multiple myeloma diagnosed globally each year.11 Research into new therapies is needed as multiple myeloma commonly becomes refractory to available treatments.3 Many patients with multiple myeloma are treated in a community cancer setting, leaving an urgent need for new, effective therapies with manageable side effects that can be administered outside of an academic centre.12,13

About Blenrep
Blenrep is a monoclonal ADC comprising a humanised BCMA conjugated to the cytotoxic agent monomethyl auristatin F via a non-cleavable linker. The drug linker technology is licensed from Seagen Inc.; the monoclonal antibody is produced using POTELLIGENT Technology licensed from BioWa Inc., a member of the Kyowa Kirin Group.

Blenrep is approved in the US14 in combination with bortezomib plus dexamethasone for the treatment of adults who have previously received at least two prior lines of therapy, including a proteasome inhibitor and an immunomodulatory agent. Blenrep has received more than 15 regulatory approvals in 2L+ relapsed or refractory multiple myeloma in combination with bortezomib and dexamethasone and in combination with pomalidomide and dexamethasone, including in the European Union15, UK16, Japan17, Canada, Switzerland, Brazil and Australia. Applications are under review in other countries globally.

About DREAMM-7
DREAMM-7 is a multicentre, open-label, randomised phase III clinical trial evaluating the efficacy and safety of BVd compared to DVd in patients with relapsed or refractory multiple myeloma who previously were treated with at least one prior line of multiple myeloma therapy, with documented disease progression during or after their most recent therapy. The trial enrolled 494 participants who were randomised 1:1 to receive either BVd or DVd. Belantamab mafodotin was administered at a dose of 2.5mg/kg intravenously every three weeks in combination for the first eight cycles and then continued as a single agent. The primary endpoint was PFS as per an independent review committee, with secondary endpoints including OS, duration of response (DOR), and minimal residual disease (MRD) negativity rate as assessed by next-generation sequencing. Other secondary endpoints include overall response rate (ORR), safety, and patient reported and quality of life outcomes.

In DREAMM-7 overall, BVd nearly tripled median PFS versus DVd (36.6 months versus 13.4 months, respectively (hazard ratio [HR]: 0.41 [95% confidence interval (CI): 0.31-0.53], p-value<0.00001). DREAMM-7 also met the key secondary endpoint of OS, showing a statistically significant and clinically meaningful 42% reduction in the risk of death at a median follow-up of 39.4 months favouring BVd (n=243) versus DVd (n=251) (HR 0.58; 95% CI: 0.43-0.79; p=0.00023). The three-year OS rate was 74% in the BVd arm and 60% in the DVd arm.2

In DREAMM-7, BVd consistently benefited a broad range of patients, including those with poor prognostic features or outcomes, such as high-risk cytogenetics or those refractory to lenalidomide. The trial also showed clinically meaningful improvements across all other secondary efficacy endpoints, including deeper and more durable responses versus the comparator.2

DREAMM-7 showed that eye-related side effects associated with Blenrep can be managed and reversed with appropriate dose modifications and follow-up. This allowed patients to maintain benefit and resulted in low rates of discontinuation due to eye-related side effects (≤9%). The most commonly reported non-ocular adverse events (>30% of participants) in the Blenrep combination arm were thrombocytopenia (87%) and diarrhoea (32%) in DREAMM-7.2

PFS results19 were presented at the American Society of Clinical Oncology (ASCO) (Free ASCO Whitepaper) Plenary Series in February 2024 and published in the New England Journal of Medicine. OS results20 were presented at the American Society of Hematology (ASH) (Free ASH Whitepaper) Annual Meeting in December 2024.

(Press release, GlaxoSmithKline, APR 20, 2026, View Source [SID1234664539])

Genprex Collaborators Present Positive Preclinical Data on the Use of Reqorsa® Gene Therapy for the Treatment of Lung Cancer at the 2026 AACR Annual Meeting

On April 20, 2026 Genprex, Inc. ("Genprex" or the "Company") (NASDAQ: GNPX), a clinical-stage gene therapy company focused on developing life-changing therapies for patients with cancer and diabetes, reported that its research collaborators presented at the 2026 American Association for Cancer Research (AACR) (Free AACR Whitepaper) Annual Meeting being held April 17-22, 2026 in San Diego, California. The collaborators presented positive preclinical data from studies of its lead drug candidate, Reqorsa Gene Therapy (quaratusugene ozeplasmid, also referred to as Quar Oze), for the treatment of lung cancer.

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"The identification of TROP2 and PTEN as potential biomarkers for primary resistance to REQORSA may provide invaluable insights for patient selection, enhancing our precision medicine strategy for our lung cancer clinical trials," said Ryan Confer, President and Chief Executive Officer at Genprex. "Furthermore, the demonstrated ability of REQORSA to induce apoptosis and decrease tumor volume in ALK-EML4 positive NSCLC cell lines and in vivo models, including those resistant to current ALK inhibitors such as alectinib, represents a potential opportunity for a future clinical trial. In addition, REQORSA’s capacity to boost Natural Killer cell antitumor activity and immunity led to observed tumor suppression and even complete tumor elimination in preclinical studies. This demonstrates REQORSA’s potential not only as a standalone agent, but also as a powerful adjunct therapy to re-sensitize resistant tumors and improve outcomes for a broad spectrum of lung cancer patients."

The featured Genprex-supported abstracts and posters presented at AACR (Free AACR Whitepaper) 2026:

Title: "TROP2 and PTEN are biomarkers of primary resistance to TUSC2 gene therapy in non-small cell lung cancer (NSCLC)"

Session Category: Experimental and Molecular Therapeutics

Session Title: Mechanisms of Drug Resistance 1

Session Date and Time: April 19, 2026 from 2-5 p.m. PT

Location: Poster Section 16

Poster Board Number: 24

Abstract Presentation Number: 391

In this study, researchers established models primarily resistant to TUSC2 gene therapy (REQORSA or Quar Oze) to find biomarkers indicative of TUSC2 gene therapy resistance in NSCLC cell lines, PDX-derived organoids (PDXOs), and patient-derived xenografts (PDXs). A panel of 10 NSCLC cell lines screened for TUSC2 sensitivity showed resistance in 50% of the cell lines, as assessed by annexin V staining and colony formation assays. Researchers evaluated TUSC2 sensitivity in 12 NSCLC PDXOs using ATP-based viability assays in 3D culture following TUSC2 or empty vector transfection. While some PDXOs were highly responsive to TUSC2 within 72 hours post-transfection, 50% of PDXOs exhibited primary resistance. TC314AR (Acquired Resistance) PDX tumors and xenograft models (A549AR, H1299AR, H23AR) were developed, grown in NSG mice, and then treated with TUSC2 gene therapy. 20-30% of tumors in every model showed resistance, with no significant reduction in size compared to the control tumors after treatment. Protein expression profiling using reverse-phase protein array (RPPA) analysis of 500 proteins showed distinct expression signatures, with several candidate biomarkers significantly altered in resistant cell lines and PDXOs. RPPA analysis of residual tumors from both the xenograft and PDX models revealed significant but model-specific alterations in protein expression between responders and non-responders. Comparative analyses across the three models showed low expression of TROP2 and high expression of PTEN as potential biomarkers of primary resistance. Overexpression of TROP2 in H1299 and H460 cells increased TUSC2-induced apoptosis. These findings suggest that TROP2 and PTEN may serve as biomarkers to predict TUSC2 response and guide therapeutic strategies in NSCLC.

Title: "Quaratusugene ozeplasmid mediated TUSC2 upregulation in EML4-ALK bearing non-small cell lung carcinoma induces apoptosis and is highly effective in preclinical studies"

Session Category: Experimental and Molecular Therapeutics

Session Title: RNA, Gene and Cell Therapies, and Enabling Assay Technologies

Session Date and Time: April 19, 2026 from 2-5 p.m. PT

Location: Poster Section 19

Poster Board Number: 12

Abstract Presentation Number: 469

In this study, researchers evaluated TUSC2 expression in a range of ALK+ cell lines and patient-derived organoids (PDOs), both prior to and following exposure to quaratusugene ozeplasmid (Quar Oze). The findings show that Quar Oze-driven TUSC2 overexpression initiates a robust pro-apoptotic response in ALK-positive (ALK+) models, not only in cells that are sensitive but also with acquired resistance (generated in the lab) to the ALK inhibitor alectinib. This is evidenced by increased pro-apoptotic markers and lower cell viability when Quar Oze is used in combination with alectinib. To further assess the Quar Oze and alectinib combination, researchers tested it in two in vivo models: (1) an alectinib-sensitive model using subcutaneous injection of NCI-H2228 ALK+ cells into nude mice, and (2) an alectinib-resistant model using ALK167 PDX implants in NSG mice. Once tumors reached ~ 100 mm³, mice were randomized into four groups: vehicle control; Quar Oze alone (25 μg/mouse, IV, every three days); alectinib alone (0.5 mg/kg for sensitive or 15 mg/kg for resistant, oral, daily); and Quar Oze plus alectinib at the same doses. In the sensitive model, tumors in the alectinib-treated group shrank by 60%. Notably, treatment with Quar Oze alone, and particularly Quar Oze combined with alectinib, resulted in 79% tumor shrinkage (p value 0.0135 versus control), demonstrating a 23% improved outcome compared to alectinib alone. This suggests that Quar Oze might serve as a valuable adjunct therapy, especially for patients who have advanced disease and/or experience resistance to TKIs.

In the resistant model, the Quar Oze and alectinib combination produced a synergistic effect, achieving the greatest tumor reduction and improved overall survival (p value 0.0001 versus control), further supporting the clinical potential of this therapeutic strategy in ALK+ NSCLC. Altogether, the in vitro and in vivo studies indicate that Quar Oze-mediated TUSC2 overexpression in ALK+ NSCLC effectively curtails tumor growth and proliferation via activation of apoptotic pathways, providing a compelling rationale for progressing toward a clinical trial.

Title: "Restoring TUSC2 function boosts NK cell cytotoxicity and antitumor immunity in vivo and in vitro"

Session Category: Immunology

Session Title: Immune Cell Biology and Tumor-Immune Crosstalk

Session Date and Time: April 19, 2026 from 2-5 p.m. PT

Location: Poster Section 8

Poster Board Number: 7

Abstract Presentation Number: 164

TUSC2, located on chromosome 3p21.3, is frequently deleted in multiple human cancers, including NSCLC, small cell lung carcinoma (SCLC), mesothelioma, breast cancer and head-and-neck cancers. Loss of TUSC2 is associated with reduced survival and increased tumor aggressiveness. Although TUSC2 is known to suppress tumor cell proliferation and induce apoptosis, its regulatory role in the immune system—particularly in innate lymphoid populations—remains insufficiently defined. Building on prior work identifying TUSC2 as a mitochondrial protein involved in calcium regulation and immune modulation, researchers hypothesized that TUSC2 exerts antitumor effects in part by enhancing NK cell cytotoxicity.

Tusc2 knockout (Tusc2 KO) and wild-type (Tusc2 WT) mice were challenged with syngeneic tumor cells (344SQ) and treated with TUSC2-expressing lipoparticles (quaratusugene ozeplasmid, Quar Oze). The therapeutic group received Quar Oze after tumor establishment starting at day 8 from cell line injection, while the prophylaxis group received Quar Oze before tumor establishment, starting 2 days before injection of cell lines. Control groups received empty lipoparticles. After three weeks from cell line injection, tumor volumes were assessed, and mice were euthanized for collection of tumors, spleens, and tumor-draining lymph nodes (TDLN). Immune cell phenotypes and cytotoxic markers were analyzed using flow cytometry.

In vitro studies evaluated NK cell cytotoxic function following Quar Oze treatment by measuring CD107a degranulation and CellTrace Violet–based proliferation. In the therapeutic treatment group, 67% of Tusc2 KO mice and 33% of Tusc2 WT mice achieved complete tumor regression, with all remaining mice showing significant tumor reduction compared with controls. Prophylactic administration did not induce complete tumor clearance but consistently reduced tumor growth across all mice. Immune profiling of the tumor microenvironment revealed that Quar Oze robustly enhanced NK cell cytotoxicity, particularly increasing granzyme B and perforin expression. In vitro assays confirmed that TUSC2 restoration significantly increased NK cell degranulation and proliferation, supporting the in vivo findings.

In conclusion, TUSC2 acts as a critical enhancer of innate antitumor immunity by boosting NK cell cytotoxic function. Therapeutic delivery of TUSC2 via Quar Oze suppresses tumor progression and, in many cases, drives complete tumor elimination. These results highlight TUSC2 as a potent immunomodulatory tumor suppressor and support its development as a dual-function therapeutic that directly targets tumor cells while also activating NK cell–mediated immunity.

These AACR (Free AACR Whitepaper) 2026 posters have been made available on Genprex’s website.

(Press release, Genprex, APR 20, 2026, View Source [SID1234664538])

Lilly to acquire Kelonia Therapeutics to advance in vivo CAR-T cell therapies

On April 20, 2026 Eli Lilly and Company (NYSE: LLY) and Kelonia Therapeutics, Inc. ("Kelonia"), a clinical-stage biotechnology company pioneering in vivo gene delivery, reported a definitive agreement for Lilly to acquire Kelonia.

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Kelonia has developed a proprietary in vivo gene placement system (iGPS ) that uses specially engineered lentiviral-based particles designed to efficiently and selectively enter T-cells inside the body, allowing the patient’s own body to generate chimeric antigen receptor T-cell (CAR-T) therapies that can treat underlying disease. Kelonia’s lead program, KLN-1010, is an investigational, one-time intravenous gene therapy that generates anti-B-cell maturation antigen (BCMA) CAR-T cells, targeting the BCMA protein expressed on the surface of multiple myeloma cells. Encouraging early clinical results were presented in the plenary session of the 2025 American Society of Hematology (ASH) (Free ASH Whitepaper) Annual Meeting, providing initial clinical validation and demonstrated promising tolerability. KLN-1010 could represent a transformative advance in the treatment of multiple myeloma by eliminating the complexities of ex vivo patient-specific cell therapy manufacturing, and pre-administration chemotherapy.

"Autologous CAR-T therapies have meaningfully improved outcomes for patients with various cancers, but significant manufacturing, safety, and access barriers mean that only a fraction of eligible patients actually receive them. Kelonia’s in vivo platform has the potential to change that by delivering rapid, durable responses in a far simpler, off-the-shelf format," said Jacob Van Naarden, executive vice president and president of Lilly Oncology and head of corporate business development. "The early clinical data for KLN-1010 are highly encouraging, both as a potential step forward for patients with multiple myeloma and as proof of concept for Kelonia’s platform. We look forward to working together with the Kelonia team to rapidly advance KLN-1010 to address patient need and recognize the full potential of their platform in other conditions where patients may benefit."

"Kelonia’s leadership in advancing the immense promise of in vivo cell therapy is unmatched, extending its reach and impact beyond the traditional boundaries of personalized medicine," said Kevin Friedman, Ph.D., chief executive officer of Kelonia. "We have demonstrated the ability to achieve deep multiple myeloma remissions with significantly reduced complexity and cost relative to ex vivo CAR T-cell approaches. In combination with Lilly’s strengths, our in vivo iGPS platform is positioned to broaden the reach of cell therapy beyond the current CAR-T landscape in hematologic malignancies and to transform treatment across a far wider range of cancers and other serious diseases. It’s been a privilege continuing the journey started by Michael Birnbaum and the Venrock team. I am deeply grateful to our employees, partners, and investigators, and most importantly, the patients who make this progress possible."

Under the terms of the agreement, Lilly will acquire Kelonia, and Kelonia shareholders will receive up to $7.00 billion in cash, inclusive of an upfront payment of $3.25 billion, and subsequent payments upon achievement of certain clinical, regulatory and commercial milestones.

The transaction is subject to customary closing conditions, including customary regulatory approvals, and is expected to close in the second half of 2026. Lilly will determine the accounting treatment of this transaction in accordance with Generally Accepted Accounting Principles (GAAP) upon closing. This transaction will thereafter be reflected in Lilly’s financial results and financial guidance.

For Lilly, Kirkland & Ellis LLP is acting as legal counsel. For Kelonia, Jefferies LLC is acting as financial advisor, and Goodwin Procter LLP is acting as legal counsel.

(Press release, Eli Lilly, APR 20, 2026, View Source [SID1234664537])

Bicycle Therapeutics Provides Update on Nuzefatide Pevedotin and EphA2 Pipeline at the AACR Annual Meeting 2026

On April 20, 2026 Bicycle Therapeutics plc (NASDAQ: BCYC), a pharmaceutical company pioneering a new and differentiated class of therapeutics based on its proprietary bicyclic peptide (Bicycle) technology, reported updates from its EphA2 pipeline at the American Association for Cancer Research (AACR) (Free AACR Whitepaper) Annual Meeting 2026.

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"EphA2 is a potentially high value target that is widely expressed in cancer and has been considered undruggable following the failure of multiple antibody-based approaches due to toxicity or insufficient efficacy. Encouraging results presented at AACR (Free AACR Whitepaper) demonstrate the potential of our Bicycle platform to drug this target with a generally well tolerated and differentiated safety profile and enhances our understanding of how best to deploy EphA2-targeted therapeutics," said Bicycle Therapeutics CEO Kevin Lee, Ph.D. "Nuzefatide pevedotin has demonstrated an emerging differentiated safety profile as a monotherapy and in combination with a checkpoint inhibitor, in over 150 patients to date. Consequently, using a combination of expression analysis, preclinical patient-derived xenograft efficacy studies, and human patient imaging, we have identified significant opportunities for this molecule in a number of cancers, including pancreatic cancer."

Dr. Lee added: "We have now identified 8mg/m2 Q2W as the preferred dose for monotherapy. Our strategy is to initially develop nuzefatide in pancreatic cancer where patients have limited available treatment options, and in parallel, to bring forward the next generation of EphA2-targeted radiotherapeutics to build on our foundational work in bladder and other EphA2-expressing tumors. Following this strategy, I am very pleased to announce that the first patient in our 2L+ pancreatic ductal adenocarcinoma Phase 2 study has been successfully dosed."

AACR Annual Meeting 2026 Data Highlights

Nuzefatide pevedotin (nuzefatide), formerly BT5528, a potentially first-in-class EphA2 targeting Bicycle Drug Conjugate (BDC), Phase 1/2 data in combination with nivolumab in metastatic urothelial cancer (mUC) patients. As of the February 9, 2026 data cutoff, results from the Phase 1/2 trial evaluating nuzefatide 6.5mg/m2 once every two weeks (Q2W) plus nivolumab 480mg once every four weeks (Q4W) in 14 patients with mUC who had previously progressed on a checkpoint inhibitor (10 while on enfortumab vedotin) showed:
40% confirmed overall response rate (ORR) (4/10) among patients with EphA2+ tumors and 100% confirmed ORR (3/3) among patients with EphA2+ tumors that were monomethyl auristatin E (MMAE)-naïve.
Patients who achieved a partial response (PR) or at least 16 weeks of stable disease (SD) were on treatment for a minimum of 56 weeks and most continued on treatment at the time of the data cut-off.
Nuzefatide in combination with nivolumab was generally well tolerated with no Grade ≥3 treatment-related adverse events (TRAEs) of clinical interest and no TRAEs of haemorrhage observed. Only one dose-limiting toxicity of Grade 3 fatigue that lasted for five days was reported and improved to Grade 1 without dose reduction.
In contrast to other EphA2-targeted agents, nuzefatide has demonstrated a positive emerging efficacy and safety profile in over 150 patients with hard-to-treat tumors to date. Further work has led Bicycle Therapeutics to determine 8mg/m2 Q2W as the preferred dose for the Phase 2 trial in patients with recurrent pancreatic ductal adenocarcinoma (PDAC).

Additional human imaging data of a Bicycle Imaging Agent (BIA) targeting EphA2 in patients with PDAC. The German Cancer Consortium (DKTK), part of a cooperative network with the German Cancer Research Center (DKFZ), presented human imaging data conducted with a Bicycle molecule targeting EphA2 labelled with gallium-68 (EphA2 BIA). Seven patients with histologically confirmed PDAC underwent PET/CT imaging up to three hours post injection of the EphA2 BIA. Data demonstrated rapid tumor uptake and excretion primarily via the kidneys in six out of seven patients. EphA2 BIA PET imaging successfully detected multiple liver, bone, lymph node, and peritoneal metastases.

These data are representative of the results seen in 15 out of 18 patients with PDAC who have undergone EphA2 BIA imaging to date. Bicycle Therapeutics believes these data validate the potential of EphA2 as a novel target in the treatment of cancer, demonstrate the translatability of preclinical data and highlight the potential of Bicycle molecules for targeted radioligand therapies and radiopharmaceutical imaging.
Preclinical assessment of nuzefatide anti-tumor activity in patient-derived xenograft (PDX) models of PDAC. Expression of EphA2 was found in all 16 PDAC PDX models. Of the 14 PDAC PDX models assessed for anti-tumor activity, 10 models were sensitive to nuzefatide, six of which showed high sensitivity. These data support the potential for nuzefatide to offer a novel option for the treatment of patients with PDAC.

In March 2026, Bicycle Therapeutics began enrolling patients in a Phase 2 clinical trial to evaluate efficacy, safety, and pharmacokinetics of nuzefatide in adult patients with recurrent PDAC, and the first patient was successfully dosed in April 2026.
Preclinical assessment of nuzefatide anti-tumor activity in cell-line-derived xenograft (CDX) models of head and neck squamous cell carcinoma (HNSCC). Nuzefatide demonstrated potent preclinical anti-tumor activity in EphA2-expressing CDX models of HNSCC.
The presentations are available in the Publications section of the Bicycle Therapeutics website.

(Press release, Bicycle Therapeutics, APR 20, 2026, View Source [SID1234664536])