Transgene Completes Patient Randomization in Phase 2 Part of Clinical Trial Evaluating TG4050 in the Adjuvant Treatment of Head and Neck Cancer

On April 13, 2026 Transgene (Euronext Paris: TNG), a biotech company that designs and develops virus-based immunotherapies for the treatment of cancer, reported the completion of patient randomization in the Phase 2 part of the Phase 1/2 clinical trial evaluating TG4050, an individualized neoantigen therapeutic vaccine (INTV) developed from Transgene’s myvac platform.

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38 patients have been randomized in the Phase 2 part of the Phase 1/2 trial for adjuvant treatment of head and neck cancer (HNSCC1). With the primary endpoint of the trial being 2-year disease-free survival (DFS), Transgene is advancing the study and expects to communicate top line results by the end of Q1 2028.

TG4050 is designed to stimulate a strong and individualized immune response aimed at preventing relapse in patients following surgery and adjuvant (chemo)radiotherapy.

Dr. Alessandro Riva, MD, Chairman and CEO of Transgene, commented: "Completing randomization in the Phase 2 part of the study is an important milestone for TG4050 and for our myvac platform and confirms the expected readout timing of the primary endpoint of the Phase 1/2 trial by the end of Q1 2028, while we plan to release first immunological data in H2 2026. We are grateful to the patients, investigators and site personnel who contribute to advancing this promising, individualized immunotherapy. We look forward to the upcoming analyses as we continue our efforts to provide an innovative individualized treatment option for patients diagnosed with operable squamous head and neck cancer."

The primary objective of the randomized multicenter Phase 1/2 trial (NCT04183166) is to compare the efficacy of TG4050 as a single agent versus watchful waiting in the adjuvant treatment of locoregionally advanced HPV-negative head and neck cancer (HNSCC).

The primary endpoint of the trial is 2-year disease-free survival (DFS) and is expected to read out as soon as all patients from the Phase 2 part achieve 2-year follow-up from randomization unless an event (relapse, death) occurs earlier, with results anticipated by the end of Q1 2028.

Data from patients in the Phase 1 part of the trial have already shown that multiple subcutaneous injections of TG4050 were well-tolerated with no unexpected safety signals.
3-year DFS follow-up of Phase 1 patients is expected in Q2/Q3 2026.

TG4050, as a monotherapy, met all trial endpoints in the Phase 1 part of the trial and induced long-lasting immune responses to vaccine neoantigens that were sustained for up to two years after treatment initiation. All patients treated with TG4050 were disease-free at 2-years (median follow-up: 30 months), confirming robust clinical proof of principle.

The positive clinical and translational data2 suggest that individualized treatment with TG4050 has the potential to prevent cancer relapses when administered as monotherapy in an adjuvant treatment regimen in patients with high risk, resected, locally advanced HPV-negative HNSCC.

(Press release, Transgene, APR 13, 2026, View Source [SID1234664310])

AnBogen Therapeutics to Present Dual Breakthroughs for Imofinostat (ABT-301) at AACR 2026: Addressing Immunotherapy Barriers in CRC and Chemo-resistance in Pancreatic Cancer

On April 13, 2026 AnBogen Therapeutics, a clinical-stage biotechnology company focused on precision oncology, reported that two key research abstracts regarding its lead compound, Imofinostat (ABT-301), have been selected for poster presentations at the 2026 American Association for Cancer Research (AACR) (Free AACR Whitepaper) Annual Meeting. The data demonstrate ABT-301’s superior performance in enhancing immunotherapy for colorectal cancer (CRC) and reveal a novel mechanism for overcoming chemotherapy resistance in pancreatic cancer.

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AnBogen will present these breakthroughs during the session "PO.ET09.01 – Epigenetic Modulators 1" on Tuesday, April 21, 2026, from 9:00 AM to 12:00 PM (Local Time) in San Diego.

1. Strengthening Immune Response: New Evidence in Colorectal Cancer (CRC)

Abstract Title: Imofinostat in combination with immune checkpoint inhibitors enhances anti-tumor activity in colorectal cancer
Abstract Number: 4496 (Section 14, Poster 15)
Key Breakthrough: Preclinical data confirms that Imofinostat, acting as an HDAC inhibitor, effectively modulates the tumor microenvironment (TME). By synergizing with immune checkpoint inhibitors and anti-angiogenic agents, it converts "cold tumors" into "hot tumors," significantly enhancing the immune system’s ability to recognize and eliminate cancer cells. This provides a robust scientific foundation for AnBogen’s ongoing global clinical trials.
2. Breaking the Defense: Targeting the HDAC3-NRF2 Pathway in Pancreatic Cancer

Abstract Title: Imofinostat enhances chemotherapy response in KRAS-mutant pancreatic ductal adenocarcinoma (PDAC) by targeting the HDAC3-NRF2 pathway
Abstract Number: 4497 (Section 14, Poster 16)
Key Breakthrough: For highly challenging KRAS-mutant pancreatic cancer, the study reveals that Imofinostat precisely regulates the HDAC3-NRF2 signaling pathway—a key driver of chemo-resistance. By intervening in this pathway, Imofinostat significantly boosts tumor sensitivity to chemotherapy, offering a promising new therapeutic strategy for patients with this aggressive malignancy.
Triple Combination Strategy for Advanced CRC

Based on the strong scientific evidence presented at AACR (Free AACR Whitepaper), AnBogen is actively advancing a Phase 1/2 global multi-center clinical trial (NCT07244705) for Imofinostat in combination with Tislelizumab (an anti-PD-1 monoclonal antibody provided by BeOne Medicines under a clinical drug supply agreement) and an anti-angiogenic agent for advanced CRC.

This triple combination strategy leverages ABT-301’s capacity to reshape the tumor microenvironment and lift immune suppression, which in turn unlocks the therapeutic potential of the PD-1 inhibitor. Through a synergistic interplay with anti-angiogenic agents, the treatment collectively promotes the normalization of tumor vasculature and optimization of the microenvironment. This integrated action effectively dismantles drug delivery barriers, allowing immune cells to penetrate deeper into the tumor core for maximum anti-cancer synergy.

"The two abstracts presented at AACR (Free AACR Whitepaper) this year represent international academic recognition of ABT-301’s innovative mechanism," said John Hsu, CEO of AnBogen Therapeutics. "We are accelerating the translation of these findings into clinical results. Furthermore, our recent successful Series B funding and upcoming plans for an Emerging Stock Market listing will provide the resources needed to drive our trials forward and address significant unmet medical needs."

About Imofinostat (ABT-301) Imofinostat is a small-molecule Histone Deacetylase inhibitor (HDACi). It reactivates tumor suppressor genes silenced by cancer cells, inducing apoptosis and inhibiting tumor growth. In Phase 1 monotherapy trials, ABT-301 demonstrated excellent safety and competitive advantages across various solid tumors.

Currently, a global multi-center Phase 1/2 clinical trial (NCT07244705) is underway to evaluate the safety and efficacy of Imofinostat in combination with Tevimbra (Tislelizumab) and Bevacizumab. This study focuses on patients with proficient mismatch repair (pMMR) or non-high microsatellite instability (Non-MSI-H) metastatic colorectal cancer (mCRC).

(Press release, Anbogen Therapeutics, APR 13, 2026, View Source [SID1234664308])

Entry into a Material Definitive Agreement

On April 12, 2026, ImageneBio, Inc., a Delaware corporation (the "Company") reported to have entered into a Securities Purchase Agreement (the "Purchase Agreement") with certain institutional and accredited investors (the "Investors"), pursuant to which the Company agreed to sell and issue pre-funded warrants to purchase shares of the Company’s voting common stock, par value $0.001 ("Common Stock" and the shares subject to the pre-funded warrants, the "Warrant Shares"), in a private placement transaction (the "Private Placement").

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The closing of the Private Placement is anticipated to occur on or about April 14, 2026 (the "Closing"), subject to customary closing conditions. At the Closing, the Company has agreed to issue and sell pre-funded warrants to purchase up to 5,770,335 Warrant Shares at a purchase price of $5.199 per Warrant Share to the Investors for gross proceeds to the Company of approximately $30 million pursuant to the Purchase Agreement.

The pre-funded warrant will have an exercise price of $0.001 per Warrant Share, subject to customary adjustments, and will be exercisable at any time after original issuance and will not expire until exercised in full. The pre-funded warrant will also be exercisable on a net exercise "cashless" basis. The pre-funded warrant may not be exercised if the aggregate number of shares of Common Stock beneficially owned by the holder thereof immediately following such exercise would exceed a specified beneficial ownership limitation, not to exceed 19.99%.

The Purchase Agreement contains customary representations, warranties and covenants that were made solely for the benefit of the parties to the Purchase Agreement. Such representations, warranties and covenants (i) are intended as a way of allocating risk between the parties to the Purchase Agreement and not as statements of fact, and (ii) may apply standards of materiality in a way that is different from what may be viewed as material by stockholders of, or other investors in, the Company. Accordingly, the Purchase Agreement is included with this filing only to provide investors with information regarding the terms of the transaction and not to provide investors with any other factual information regarding the Company. Investors should not rely on the representations, warranties and covenants or any descriptions thereof as characterizations of the actual state of facts or condition of the Company or any of its subsidiaries or affiliates. Moreover, information concerning the subject matter of the representations and warranties may change after the date of the Purchase Agreement, which subsequent information may or may not be fully reflected in public disclosures.

Registration Rights Agreement

In connection with the Private Placement, the Company has agreed to enter into a Registration Rights Agreement (the "Registration Rights Agreement") with the Investors at the Closing, pursuant to which the Company will agree to prepare and file, within three business days following August 1, 2026, subject to certain allowable delays, a registration statement with the U.S. Securities and Exchange Commission (the "SEC") to register for resale the Warrant Shares issuable upon the exercise of the pre-funded warrants that were issued and sold under the Purchase Agreement, and generally to cause the applicable registration statement to promptly become effective. Certain cash penalties will apply to the Company in the event of registration failures, as described in the Registration Rights Agreement.

The foregoing summaries of the Purchase Agreement, the pre-funded warrant and the Registration Rights Agreement do not purport to be complete and are qualified in their entirety by reference to the complete text of the Purchase Agreement, the form of pre-funded warrant and the Registration Rights Agreement, which are filed with this report as Exhibits 10.1, 4.1 and 4.2, respectively.

(Filing, ImaGene, APR 12, 2026, View Source [SID1234664319])

AbbVie Showcases Late‑Breaking Phase 2 Data for Mirvetuximab Soravtansine-gynx (ELAHERE®) in Platinum‑Sensitive Ovarian Cancer (PSOC) at SGO 2026

On April 12, 2026 AbbVie (NYSE: ABBV) reported that late-breaking results from the Phase 2 IMGN853-0420 trial will be presented in an oral session at the 2026 Society of Gynecologic Oncology (SGO) Annual Meeting (San Juan, Puerto Rico; April 10-13, 2026). The study evaluated the potential efficacy and safety of mirvetuximab soravtansine-gynx, a first-in-class antibody-drug conjugate (ADC), in combination with carboplatin followed by maintenance of mirvetuximab soravtansine-gynx monotherapy, in patients with folate receptor alpha (FRα)-expressing, recurrent platinum‑sensitive ovarian cancer (PSOC).

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The multicenter, open-label study enrolled 125 patients with FRα‑positive, measurable disease who had received one prior platinum‑based chemotherapy regimen. Participants received mirvetuximab soravtansine-gynx plus carboplatin every three weeks for six to eight cycles, followed by single-agent mirvetuximab soravtansine-gynx as a continuation therapy. Nearly half of patients had prior exposure to a polymerase inhibitor (PARPi), a patient population who may experience reduced responses to subsequent platinum-based chemotherapy.1

The primary endpoint of the study was a confirmed objective response rate (ORR) in the ≥50% FRα subgroup after six cycles of combination therapy.2 Key secondary endpoint was ORR after six cycles in the overall population (FRα ≥25%) and additional secondary endpoints included duration of response (DoR), progression-free survival (PFS) and overall survival (OS).

"Despite being considered chemotherapy-responsive, platinum-sensitive ovarian cancer (PSOC) remains challenging to treat. With each recurrence, responses to standard platinum-based chemotherapy often diminish and patients may experience cumulative toxicities,"3 said Daejin Abidoye, M.D., vice president, therapeutic area head, oncology, solid tumor and hematology, AbbVie. "These results are encouraging and further support the potential of mirvetuximab soravtansine-gynx in PSOC as a novel treatment regimen."

Key highlights from the late-breaking oral presentation include:

Response rates across combination regimen: By the end of the induction phase, confirmed ORR was 62.7% (95% CI, 52.6–72.1) in the FRα ≥50% subgroup and 62.4% (95% CI, 53.3–70.9) in the overall population. 81% of patients (101/125) showed no disease progression and continued treatment with single-agent mirvetuximab soravtansine.2 Median DoR was 11.2 months across the overall population.2
Additional responses with continuation monotherapy: Among patients who were on the combination and transitioned to mirvetuximab soravtansine-gynx monotherapy, ORR was 68% (59.1–76.1) across the overall population.2
Responses in patients with prior exposure to polymerase inhibitor (PARPi): In nearly half of patients (49%) in the overall population (FRα ≥25%) who had prior PARPi exposure, ORR was 63.9% (50.6–75.8).2
Safety data: The safety profile of mirvetuximab soravtansine-gynx was consistent with findings from previous studies. The most common treatment-related adverse events (TRAEs) with mirvetuximab soravtansine-gynx plus carboplatin followed by a continuation of mirvetuximab-soravtansine-gynx alone were low‑grade ocular events, including corneal changes that were reversible in over 90% of patients.2 The most common grade ≥3 TRAEs (>5%) were neutropenia (15%), blurred vision (10%), thrombocytopenia (10%), cataract (6%), dry eye (5%), diarrhea (5%) and peripheral sensory neuropathy (5%).2
"The combination of mirvetuximab soravtansine-gynx and carboplatin delivered strong responses in this Phase 2 study and many patients continued to experience responses during the monotherapy treatment phase," said Gottfried E. Konecny, M.D., Professor of Medicine, David Geffen School of Medicine at UCLA, and primary investigator. "These findings support further investigation of a novel treatment approach that integrates antibody drug conjugates with standard chemotherapy in patients with folate receptor alpha (FRα)-expressing recurrent platinum‑sensitive ovarian cancer and in patients previously treated with PARP inhibitors who often face resistance and remain in need of additional options."

The data is being presented during the Rapid-Fire Oral III: Translational and ADC session on Sunday, April 12 at 12:32 PM ET. More information about the 2026 SGO Annual Meeting and abstracts being presented are available here.

Further information on AbbVie clinical trials is also available at View Source

Use of mirvetuximab soravtansine-gynx plus carboplatin followed by mirvetuximab soravtansine-gynx continuation in FRα-expressing recurrent PSOC is not approved in the U.S. or in the E.U. or in any other territory. The safety and efficacy of mirvetuximab soravtansine-gynx for use as a combination therapy in PSOC have not been established.

About the IMGN853-0420 Trial
IMGN853‑0420 (NCT05456685) is a multicenter, open‑label, single-arm Phase 2 study evaluating the efficacy and safety of carboplatin plus mirvetuximab soravtansine-gynx followed by mirvetuximab soravtansine-gynx continuation in folate receptor‑alpha (FRα) positive (≥25% tumor cells with ≥2+ membrane intensity), recurrent platinum-sensitive high‑grade epithelial ovarian, primary peritoneal, or fallopian tube cancer following one prior line of platinum‑based chemotherapy. After completing six cycles of mirvetuximab soravtansine-gynx plus carboplatin, participants without progressive disease continue on single‑agent mirvetuximab soravtansine-gynx. Eligibility requires confirmed FRα positivity using the Ventana FOLR1 Assay, ensuring enrollment of participants most likely to benefit from this FRα‑targeted ADC approach.

About ELAHERE
ELAHERE (mirvetuximab soravtansine-gynx) is a first-in-class antibody-drug conjugate (ADC) comprising a folate receptor alpha-binding antibody, cleavable linker and the maytansinoid payload DM4, a potent tubulin inhibitor designed to kill the targeted cancer cells. ELAHERE is currently indicated for the treatment of adult patients with folate receptor-alpha (FRα) positive, platinum-resistant epithelial ovarian, fallopian tube or primary peritoneal cancer, who have received one to three prior systemic treatment regimens. It is being investigated in patients with platinum-sensitive ovarian cancer.

ELAHERE U.S. USE and IMPORTANT SAFETY INFORMATION

What is ELAHERE?

ELAHERE is a prescription medicine used to treat adults with folate receptor-alpha positive ovarian cancer, fallopian tube cancer, or primary peritoneal cancer who:

have not responded to or are no longer responding to treatment with platinum-based chemotherapy and
have received 1 to 3 prior types of chemotherapy.
Your healthcare provider will perform a test to make sure that ELAHERE is right for you.
It is not known if ELAHERE is safe and effective in children.

IMPORTANT SAFETY INFORMATION

What is the most important information I should know about ELAHERE?

ELAHERE can cause serious side effects, including:

Eye problems. Eye problems are common with ELAHERE and can also be severe. Tell your healthcare provider right away if you develop any eye problems during treatment with ELAHERE, including blurred vision, dry eyes, sensitivity to light, eye pain, eye redness, or new or worsening vision changes.

Your healthcare provider will send you to see an eye care professional to check your eyes before you start treatment with ELAHERE, during treatment with ELAHERE, and as needed for any worsening signs and symptoms of eye problems.
Your healthcare provider will prescribe steroid eye drops and lubricating eye drops before you start and during your treatment with ELAHERE. You should use eye drops as directed by your healthcare provider.
Do not wear contact lenses throughout your treatment with ELAHERE unless you are told to use them by your healthcare provider.
What should I tell my healthcare provider before receiving ELAHERE?

Tell your healthcare provider about all of your medical conditions, including if you:

have vision or eye problems.
have numbness or tingling in your hands or feet.
have liver problems.
are pregnant or plan to become pregnant. ELAHERE can harm your unborn baby. Tell your healthcare provider right away if you become pregnant or think you may be pregnant during treatment with ELAHERE.
Patients who are able to become pregnant:
Your healthcare provider should do a pregnancy test before you start treatment with ELAHERE.
You should use an effective birth control (contraception) during treatment and for 7 months after your last dose of ELAHERE.
are breastfeeding or plan to breastfeed. It is not known if ELAHERE passes into your breast milk. Do not breastfeed during treatment and for 1 month after your last dose of ELAHERE.
Tell your healthcare provider about all the medicines you take, including prescription and over-the-counter medicines, vitamins, and herbal supplements. Taking certain other medicines during treatment with ELAHERE may cause side effects.

What are the possible side effects of ELAHERE?

ELAHERE can cause serious side effects, including:

Eye problems. Eye problems are common with ELAHERE and can also be severe. Tell your healthcare provider right away if you develop any eye problems during treatment with ELAHERE, including blurred vision, dry eyes, sensitivity to light, eye pain, eye redness, or new or worsening vision changes.
Lung problems (pneumonitis). ELAHERE can cause severe or life-threatening inflammation of the lungs that may lead to death. Tell your healthcare provider right away if you get new or worsening symptoms, including trouble breathing, shortness of breath, cough, or chest pain.
Peripheral neuropathy. Nerve problems called peripheral neuropathy are common during treatment with ELAHERE and can also be severe. Your healthcare provider will monitor you for signs and symptoms of nerve problems. Tell your healthcare provider if you get new or worsening numbness, tingling, burning sensation or pain in your hands or feet or muscle weakness.
The most common side effects and abnormal labs of ELAHERE include:

increased liver enzymes in the blood
feeling tired
blurred vision
nausea
diarrhea
stomach-area (abdominal) pain
changes in the cornea (part of the eye)
peripheral neuropathy
muscle, bone, or joint pain
decreased red or white blood cell counts

decreased platelets
decreased magnesium level in the blood
dry eye
constipation
vomiting
decreased albumin level in the blood
decreased appetite
Your healthcare provider may change your dose of ELAHERE, delay treatment, or completely stop treatment if you have certain side effects.

These are not all of the possible side effects of ELAHERE. Call your doctor for medical advice about side effects. You are encouraged to report side effects of prescription drugs to the FDA. Visit www.fda.gov/medwatch or call 1‑800‑FDA‑1088.

(Press release, AbbVie, APR 12, 2026, View Source [SID1234664309])

GSK presents positive data for B7-H4-targeted ADC in gynaecological cancers

On April 12, 2026 GSK plc (LSE/NYSE: GSK) reported positive findings from its global phase I BEHOLD-1 clinical trial for mocertatug rezetecan (or Mo-Rez for short), a novel antibody-drug conjugate (ADC) targeting the B7-H4 antigen. At the highest doses evaluated, Mo-Rez monotherapy achieved confirmed objective response rates (cORR) of 62% (5.8 mg/kg n=21/34; 95% CI: 44, 78) in platinum-resistant ovarian cancer (PROC) and 67% (4.8 mg/kg n=8/12; 95% CI: 35, 90) in recurrent or advanced endometrial cancer (EC).1 These data will be presented for the first time in a late-breaking oral session at the Society of Gynecologic Oncology (SGO) Annual Meeting on Women’s Cancer in San Juan, Puerto Rico.

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Currently, there are limited treatment options with modest response rates for patients with PROC and advanced EC. B7-H4 is an immune checkpoint that is widely expressed in ovarian and endometrial cancers and is low in normal tissues, providing potential for a differentiated precision-therapy. The response to Mo-Rez observed across a range of B7-H4 expression levels reinforces its broad potential in gynaecologic cancers and further validates the relevance of targeting B7-H4.

Hesham Abdullah, Senior Vice President, Global Head Oncology, R&D, GSK, said: "Treatment of gynaecological cancers remains a major challenge, with a pressing need for new therapies that offer improved response rates. With Mo-Rez, we now have compelling evidence of a promising clinical profile, with response rates that support accelerating development into five pivotal global phase III trials later this year across ovarian and endometrial cancers, including earlier line settings."

Ana Oaknin, Study Investigator for BEHOLD-1, Medical Oncology Department, Hospital Universitario Puerta de Hierro-Majadahonda, Madrid, Spain said: "In the early phase BEHOLD-1 study, we saw meaningful antitumour activity for this patient dataset, with response rates higher than typically seen in ADCs in development, and a manageable safety profile. For patients with platinum-resistant ovarian cancer and recurrent endometrial cancer, these findings are particularly encouraging."

At the highest doses evaluated in BEHOLD-1, few patients needed to stop treatment because of a treatment-related adverse events (TRAE) (0% in PROC and 4% in EC). The most common TRAE was nausea (82% in PROC; 75% in EC). Grade ≥3 TRAEs occurred in 64% and 54% patients in PROC and EC, respectively, and were predominantly haematologic, as expected for treatments in this class. Overall rates of interstitial lung disease or pneumonitis were low (3%; 5 out of 178 patients) and all cases were mild to moderate (grade 1-2). The interim analysis showed the median duration of response had not yet been reached. Based on the findings from this study, the recommended dose for the first of the phase III trials, BEHOLD-Ovarian01 and BEHOLD-Endometrial01, is 5.8 mg/kg.

About the BEHOLD clinical trial programme
The BEHOLD clinical programme is GSK’s global development plan that includes the BEHOLD-1 (NCT06431594) monotherapy study and the ongoing BEHOLD-2 (NCT06796907) combination study. Mo-Rez will advance to five pivotal global phase III trials in 2026, starting with PROC (BEHOLD-Ovarian01 / NCT07286266) and 2L EC (BEHOLD-Endometrial01 / NCT07286331). Additional phase III studies will evaluate Mo‑Rez in platinum‑sensitive ovarian cancer (BEHOLD-Ovarian02) and in first‑line maintenance settings for ovarian cancer without homologous recombination deficiency (BEHOLD-Ovarian03) and mismatch‑repair–proficient endometrial cancer (BEHOLD-Endometrial02).

About BEHOLD-1
The BEHOLD-1 clinical trial is a two-part, open-label, phase I study evaluating the safety, tolerability and efficacy of Mo-Rez injection in patients with PROC or advanced/recurrent EC. Phase Ia assessed up to four Mo-Rez dose levels in patients with advanced solid tumours, with intravenous administration every three weeks until progression or toxicity. In the phase Ib dose expansion, patients with PROC or EC (1–3 prior lines of therapy) were randomised to three or two Mo-Rez dose levels, respectively.

At data cut-off, a total of 224 patients were enrolled in BEHOLD-1; n=44 in phase 1a (n=21 PROC, n=23 mix of other solid tumours) and n=180 in phase Ib (n=131 PROC, n=49 EC). Primary endpoints included: incidence of dose-limiting toxicity in phase Ia and confirmed ORR (cORR) by investigator per RECIST 1.1 in phase Ib. At the highest dose evaluated in phase Ib, the most common adverse events in PROC were nausea (86%), neutropenia/neutrophil count decreased (73%), anaemia (52%), fatigue (52%) and alopecia (52%). In EC, the most common adverse events were nausea (79%), neutropenia/neutrophil count decreased (58%), anaemia (54%), vomiting (46%) and fatigue (42%). Treatment related adverse events led to dose interruptions in 39% of patients with PROC and 21% of those with EC, and to dose reductions in 39% in PROC and 17% in EC, at the highest dose. The trial is ongoing and currently in the dose expansion phase.

About mocertatug rezetecan
Mo-Rez is a novel investigational B7-H4-targeted antibody-drug conjugate designed to optimise efficacy and tolerability. It is composed of a fully human anti-B7-H4 monoclonal antibody covalently linked to a topoisomerase inhibitor payload and has a drug-to-antibody ratio (DAR) of 6. GSK acquired exclusive worldwide rights (excluding China’s mainland, Hong Kong, Macau, and Taiwan) from Hansoh Pharma to progress clinical development and commercialisation of Mo-Rez globally.

About ovarian cancer and endometrial cancer
Endometrial cancer affects 1.6 million people globally, with 417,000 new cases each year and 15% to 20% of patients presenting in later stages of the disease.2,3 Ovarian cancer affects 843,000 people with 240,000 new cases annually.4 70% of these patients present with advanced disease.5 Recurrence is common in advanced cases of disease, up to 67% in endometrial cancer and 70% in ovarian cancer, and survival usually declines after recurrence.

(Press release, GlaxoSmithKline, APR 12, 2026, View Source [SID1234664307])