On June 2, 2025 Innovent Biologics, Inc. ("Innovent") (HKEX: 01801), a world-class biopharmaceutical company that develops, manufactures and commercializes high-quality medicines for the treatment of oncology, cardiovascular and metabolic, autoimmune, ophthalmology and other major diseases, reported updated Phase 1 study results of IBI343, a novel anti-CLDN18.2 ADC, for the treatment of advanced pancreatic cancer at the 2025 American Society of Clinical Oncology (ASCO) (Free ASCO Whitepaper) Annual Meeting (Press release, Innovent Biologics, JUN 2, 2025, View Source [SID1234653637]).

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With extended follow-up and more mature data on progression-free survival (PFS) and overall survival (OS), IBI343 has demonstrated promising therapeutic efficacy in patients with CLDN18.2-positive advanced pancreatic cancer. These encouraging results suggest the potential of IBI343 in this challenging-to-treat malignancy. Supported by these robust clinical findings, IBI343 has been granted Breakthrough Therapy Designation (BTD) by China’s National Medical Products Administration (NMPA). Concurrently, the Phase 1 clinical trial of IBI343 is also being conducted in the United States, where the drug candidate has received Fast Track Designation (FTD) from the U.S. Food and Drug Administration (FDA).

Pancreatic cancer is one of the most aggressive malignancies worldwide. Most patients are diagnosed in the middle and late stages and often develop resistance to standard chemotherapy, resulting in a 5-year survival rate of less than 10%1. According to the GLOBOCAN 2022 statistics2, there are approximately 510,000 new cases and 467,000 deaths globally from pancreatic cancer each year, with China accounting for 120,000 new cases and 110,000 deaths annually.

This Phase 1/1b study is a multi-regional, dose escalation and expansion clinical trial (NCT05458219). Preliminary data were presented at ASCO (Free ASCO Whitepaper) 2025 and ESMO (Free ESMO Whitepaper) Asia 2024 and the updated results from the study’s dose-expansion cohort were presented at the 2025 ASCO (Free ASCO Whitepaper) as follows:

As of March 14, 2025, a total of 83 patients with pancreatic cancer had received at least one dose of IBI343 with a median follow-up time of 11.1 months.
As the data cutoff date, in patients with CLDN18.2 1+2+3+≥60% expression treated at the 6mg/kg dose (N=44), the confirmed overall objective response rate (cORR) was 22.7% and the disease control rate (DCR) was 81.8%. The median progression-free survival (mPFS) was 5.4 months, and the median overall survival (mOS) was 9.1 months. Among them, 17 patients had received only one line of prior treatment, achieving a mPFS of 5.4 months and a mOS of 12.1 months; and 18 patients had received two lines of prior treatment, the mPFS was 5.3 months and the mOS was 9.1 months.
The updated safety results demonstrated the favorable safety profile of IBI343 with a consistently low rate of gastrointestinal toxicity and no new safety signals. 98.8% of the patients experienced treatment-emergent adverse events (TEAEs), with the most common TEAEs being anemia, neutrophil count decreased, and white blood cell count decreased. Notably, no ≥ grade 3 nausea and vomiting occurred.
Professor Xianjun Yu from Fudan University Cancer Hospital, said, "Pancreatic cancer is one of the most malignant tumors of the digestive tract. Most patients are already in the advanced stage when diagnosed, and the 5-year survival rate is only about 10%1. Currently, chemotherapy is still the main first- and second-line treatment for advanced pancreatic cancer. The clinical options for second-line treatment are particularly limited, with a chemotherapy response rate of only 6-16%, median progression free survival of 2 to 5 months, and a median survival of approximately 6 to 9 months3, representing an urgent clinical need. With longer follow-up, the mature PFS and OS data from the latest IBI343 update demonstrate promising therapeutic potential, suggesting a breakthrough in this difficult-to-treat malignancy."

Dr. Hui Zhou, Senior Vice President of Innovent, said, "We are pleased to present an oral update on IBI343’s clinical data at this year’s ASCO (Free ASCO Whitepaper) conference. With the unique Fc-silent antibody design, stable linker and potent TOPO1i payload, IBI343 is the first ADC candidate to show encouraging efficacy and a favorable safety profile in the treatment of advanced pancreatic cancer. We hope to continue advancing the clinical trials of IBI343 for pancreatic cancer patients. Innovent will leverage its unique strengths in R&D innovation and clinical translation to develop a new generation of globally competitive oncology – focused innovative pipeline to benefit patients worldwide.."

About IBI343（Anti-CLDN18.2 ADC）

IBI343 is a recombinant human anti-CLDN18.2 monoclonal antibody-drug conjugate (ADC) developed by Innovent Biologics. IBI343 binds to the CLDN18.2-expressing tumor cells, the CLDN18.2 dependent ADC internalization will occur and the drug is released resulting in DNA damage and eventually apoptosis of the tumor cells. The freed drug can also diffuse across the plasma membrane to reach and kill the neighboring cells, resulting in "bystander killing effect".

As an innovative TOPO1i ADC, IBI343 has demonstrated tolerable safety and encouraging efficacy signals in Phase 1 clinical studies. The therapeutic potential of IBI343 is currently being explored in tumor types such as gastric and pancreatic cancer.

The Phase 3 trial of IBI343 for advanced gastric / gastroesophageal junction adenocarcinoma is now recruiting patients. The relevant indication has been included in China’s NMPA breakthrough therapy list.

IBI343’s Phase 1 trial for advanced pancreatic ductal adenocarcinoma is enrolling patients in an multi-regional study. This indication has received Fast Track designation from the FDA and been included in the NMPA’s BTD list.

On June 2, 2025 PanGIA Biotech, a leader in non-invasive cancer diagnostics, reported findings at the 2025 Annual Meeting of the American Society of Clinical Oncology (ASCO) (Free ASCO Whitepaper) from a prospective, multi-center validation study evaluating its AI-powered, urine-based platform for early-stage prostate cancer detection (Press release, PanGIA Biotech, JUN 2, 2025, View Source [SID1234653653]).

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The study, Development and validation of an AI-enabled prediction of prostate cancer (PCa) using urine-based liquid biopsy (Abstract #3080), is the first to clinically validate PanGIA’s novel approach—pairing proprietary chemistry with machine learning to detect cancer-specific biosignatures from a single, non-invasive urine sample.

"This study confirms what we’ve believed from the start: there’s power in non-invasive, data-driven diagnostics," said Holly Magliochetti, CEO of PanGIA Biotech. "Our platform helps clinicians detect prostate cancer when intervention is most effective—without costly or invasive procedures."

Key findings presented included:

Study Cohort: 197 biopsy-confirmed prostate cancer patients and 84 healthy controls.

Classifier Performance: Achieved an F1 score of 0.843 with a recall of 0.967 in distinguishing cancer from non-cancer subjects.

Gleason Score Cohorts: Maintained high recall (>0.89) across Gleason scores 6 through 10, with F1 scores ranging from 0.799 to 0.838.

Non-Invasive Advantage: Demonstrated strong performance in detecting intermediate- and low-grade cancers, offering a less invasive alternative to traditional diagnostics.
Unlike invasive biopsies or blood-based tests that often miss early-stage cases, PanGIA’s approach analyzes urinary biosignatures using proprietary AI models—eliminating the need for sequencing and enabling cost-effective, globally scalable testing.

Previously published in The Analyst, a journal of the Royal Society of Chemistry¹, the PanGIA platform is designed for diverse healthcare environments and holds promise for broad global adoption.

On June 2, 2025 Sanofi and Blueprint Medicines Corporation (Blueprint), a US-based, publicly traded biopharmaceutical company specializing in systemic mastocytosis (SM), a rare immunological disease, and other KIT-driven diseases, reported to have entered into an agreement under which Sanofi will acquire Blueprint (Press release, Blueprint Medicines, JUN 2, 2025, View Source [SID1234653560]).

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The acquisition includes a rare immunology disease medicine, Ayvakit/Ayvakyt (avapritinib), approved in the US and the EU, and a promising advanced and early-stage immunology pipeline. Furthermore, Blueprint’s established presence among allergists, dermatologists, and immunologists is expected to enhance Sanofi’s growing immunology pipeline.

Ayvakit/Ayvakyt is the only approved medicine for advanced and indolent systemic mastocytosis (ASM & ISM), a rare immunology disease, which is characterized by the accumulation and activation of aberrant mast cells in bone marrow, skin, the gastrointestinal tract, and other organs. The acquisition will also bring elenestinib, a next-generation medicine for SM, as well as BLU-808, a highly selective and potent oral wild-type KIT inhibitor that has the potential to treat a broad range of diseases in immunology.

Under the terms of the acquisition, Sanofi will pay $129.00 per share in cash at closing, representing an equity value of approximately $9.1 billion. Blueprint shareholders also will receive one non-tradeable contingent value right (CVR) which will entitle the holder to receive two potential milestone payments of $2 and $4 per CVR for the achievement, respectively, of future development and regulatory milestones for BLU-808. The total equity value of the transaction, including potential CVR payments, represents approximately $9.5 billion on a fully diluted basis.

Paul Hudson
CEO, Sanofi
"The proposed acquisition of Blueprint Medicines represents a strategic step forward in our rare and immunology portfolios. It enhances our pipeline and accelerates our transformation into the world’s leading immunology company. This acquisition is fully aligned with our strategic intent to strengthen our existing therapeutic areas, to bring relevant and differentiated medicines to patients and to secure attractive returns to our shareholders. It complements recent acquisitions of early-stage medicines that remain our main field of interest. Sanofi still retains a sizeable capacity for further acquisitions. We are excited to welcome Blueprint’s talented people and we look forward to chasing the miracles of science together. This makes sense for science, for both companies, for healthcare professionals, and – most of all – for patients."

Kate Haviland
CEO, Blueprint Medicines
"Since our founding, Blueprint Medicines has worked at the intersection of scientific innovation and operational excellence. I’m incredibly proud of the medical innovations our people have created and delivered to patients. We have translated our unique scientific understanding of mast cell biology into a portfolio of important therapies including Ayvakit – the first and only medicine approved to treat the root cause of systemic mastocytosis – and worked collaboratively with communities to improve standards of care and patient outcomes. With this agreement, we begin our next chapter with Sanofi, whose exceptional leadership in rare disease and immunology and proven ability to solve medical challenges at scale stand to accelerate our joint mission to bring life-changing medicines to many more patients around the world."

Mast cells play an important role in immune responses and are typically found in tissues that encounter the external environment, such as the skin, lungs, and gastrointestinal tract. Upon activation, mast cells release pro-inflammatory molecules such as histamines and proteases. Systemic mastocytosis is a rare immunologic disorder that can lead to a range of debilitating symptoms across multiple organ systems and a significant impact on patients’ quality of life. The symptoms that patients with SM experience can include anaphylaxis, bone disease, gastrointestinal distress and skin lesions. ISM represents the majority of SM cases.

Ayvakit achieved net revenues of $479 million in 2024 and nearly $150 million in Q1 2025, representing year-on-year growth of more than 60 percent over Q1 2024. The oral medicine is a potent and selective inhibitor of activated KIT and PDGFRA mutant kinases. In certain diseases, mutations in KIT and PDGFRA force protein kinases into an increasingly active state and Ayvakit/Ayvakyt is designed to bind and inhibit these proteins.

Elenestinib is a next-generation, potent and highly selective KIT D816V inhibitor with limited central nervous system penetration. The oral investigational ISM medication is the subject of HARBOR, a phase 2/3 study (clinical study identifier: NCT04910685). The ongoing, randomized, double-blind, placebo-controlled study is designed to evaluate the efficacy and safety of elenestinib plus symptom-directed therapy in patients with ISM and smoldering SM.

BLU-808 is an investigational oral, highly potent and selective wild-type KIT inhibitor that was developed leveraging Blueprint’s expertise in mast cell biology. Wild-type KIT plays a central role in mast cell activation, which is implicated in a broad range of inflammatory diseases.

Transaction terms and financial considerations
Under the terms of the merger agreement, Sanofi will commence a cash tender offer to acquire all outstanding shares of Blueprint for $129.00 per share in cash, reflecting a total equity value of approximately $9.1 billion. In addition, Blueprint’s shareholders will receive one non-tradeable CVR per Blueprint share with two potential milestone payments as follows:

$2 per share, conditioned upon the achievement of a clinical development milestone for BLU-808, and
$4 per share, conditioned upon the achievement of a regulatory milestone for BLU-808.
The upfront offer price represents a premium of approximately 27% over the closing price of Blueprint on May 30, 2025 and a premium of approximately 34% over the 30 trading days volume weighted average price (VWAP) of Blueprint as of May 30, 2025. Together with the CVR, the premium is approximately 33% over the closing price on May 30, 2025 and approximately 40% over the 30 trading days VWAP.

The consummation of the tender offer is subject to customary closing conditions, including the tender of a number of shares of Blueprint common stock representing at least a majority of the outstanding shares of Blueprint common stock, the receipt of required regulatory approvals, and other customary conditions.

If the tender offer is successfully completed, a wholly owned subsidiary of Sanofi will merge with and into Blueprint and all of the outstanding Blueprint shares that are not tendered in the tender offer will be converted into the right to receive the same $129.00 per share in cash and one CVR per share offered to Blueprint shareholders in the tender offer. Sanofi plans to finance the transaction with a combination of cash on hand and proceeds from new debt. The tender offer is not subject to any financing condition. Subject to the satisfaction or waiver of customary closing conditions, Sanofi currently expects to complete the acquisition in the third quarter of 2025. The acquisition will not have a significant impact on Sanofi’s financial guidance for 2025. It is immediately accretive to gross margin and accretive to business operating income and EPS after 2026.

Conference call for investors and analysts
Sanofi will host a conference call for investors and analysts at 08:30 CEST today. A presentation will be available for download from the Investor Relations section of sanofi.com before the conference call starts.

The call will be held on Zoom with the following access details:
View Source
Webinar ID: 979 9146 5119
Passcode: 801394

About Ayvakit
Ayvakit (avapritinib) is the first and only medicine approved by the US Food and Drug Administration (FDA) to treat the root cause of SM. It was FDA approved for the treatment of advanced SM in June 2021 and indolent SM in May 2023. It now is indicated in adults with ISM, adults with advanced SM, including aggressive SM (ASM), SM with an associated hematological neoplasm (SM-AHN) and mast cell leukemia (MCL), and adults with unresectable or metastatic gastrointestinal stromal tumor (GIST) harboring a PDGFRA exon 18 mutation, including PDGFRA D842V mutations. The medicine is approved in the EU as Ayvakyt for the treatment of adults with ISM with moderate to severe symptoms inadequately controlled on symptomatic treatment, adults with ASM, SM-AHN or MCL, after at least one systemic therapy, and adults with unresectable or metastatic GIST harboring the PDGFRA D842V mutation. Globally, the medicine is approved for one or more indications in 16 countries, including China where it is marketed by CStone Pharmaceuticals, paying tiered percentage royalties on sales.

On June 2, 2025 Genmab A/S (Nasdaq: GMAB) reported new data from cohort B2 of the Phase 1/2 RAINFOL-01 trial evaluating rinatabart sesutecan (Rina-S), an investigational folate receptor alpha (FRα)-targeted, TOPO1-inhibitor antibody-drug conjugate (ADC). The study showed that with a median on-study follow-up of 7.7 months, treatment with Rina-S 100 mg/m2 every 3 weeks (Q3W) resulted in a 50.0 percent confirmed objective response rate (ORR), including two complete responses (CR), in heavily pre-treated advanced endometrial cancer (EC) patients who experienced disease progression on or after treatment with platinum-based chemotherapy and an immune checkpoint inhibitor (Press release, Genmab, JUN 2, 2025, View Source [SID1234653606]). The median duration of response (mDOR) was not reached. These data are from the endometrial cancer monotherapy dose expansion B2 cohort of the multi-part RAINFOL-01 trial evaluating the safety and efficacy of Rina-S in solid tumors and were presented at the 2025 American Society of Clinical Oncology (ASCO) (Free ASCO Whitepaper) Annual Meeting in Chicago, Illinois.

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"Advanced stage and recurrent endometrial cancer often lead to resistance to standard of care options. When this occurs, prognosis worsens and treatment options become increasingly limited, leaving patients and clinicians to navigate difficult decisions," said Ira Winer, M.D., Ph.D., FACOG, study investigator and Professor, Division of Gynecologic Oncology and Phase I Developmental Therapeutics at the Karmanos Cancer Institute, Wayne State University. "These Phase 1/2 results demonstrate encouraging data with Rina-S in this patient population and support its further development as a potential therapy for patients with advanced and recurrent endometrial cancer."

The B2 cohort of the Phase 1/2 RAINFOL-01 study (NCT05579366) is a dose expansion cohort evaluating the efficacy and safety of Rina-S in patients with advanced or recurrent endometrial cancer. In the study, 64 patients with heavily pretreated advanced or recurrent endometrial cancer whose disease had progressed on or after an anti-PD-(L)1 and platinum-based chemotherapy were enrolled and treated with Rina-S. Patients were administered either 100 mg/m2 (n=22) or 120 mg/m2 (n=42) of Rina-S. In the 100 mg/m2 cohort, the confirmed ORR was 50.0 percent, including two CRs. Anti-tumor activity was also observed in patients treated with Rina-S 120 mg/m2 Q3W, which resulted in 47.1 percent confirmed ORR. The mDoR was not reached after a median follow-up of 7.7 months in the 100 mg/m2 cohort and a median follow-up of 9.8 months in the 120 mg/m2 cohort. Median age was 67.0 years and 69.5 years in the 100 mg/m2 and 120 mg/m2 cohorts, respectively. Study participants were previously treated with a median of three lines of therapy (range 1-8).

Common treatment emergent adverse events (TEAEs; all grades) included diarrhea, shortness of breath (dyspnea), urinary tract infection, headache, constipation, decreased appetite, vomiting, fatigue and nausea. Serious TEAEs (Grade 3 or higher) occurred in 31.8 percent and 50.0 percent of patients treated with Rina-S 100 mg/m2 and 120 mg/m2, respectively. Hematologic adverse events were manageable without significant dose reduction and with low rates of treatment discontinuation. No signals of ocular toxicities, neuropathy or Interstitial Lung Disease (ILD) were observed. Ocular toxicities and ILD are often reported as adverse events associated with ADCs i,ii,iii,iv.

"Rina-S represents the kind of innovation that defines our focus at Genmab, which is to develop wholly owned, novel antibody-based medicines that have the potential to transform the treatment of cancer and address an unmet need, including for patients with advanced endometrial cancer," said Judith Klimovsky, M.D., Executive Vice President and Chief Development Officer of Genmab. "The encouraging early signals in endometrial cancer underscore our deep commitment to making a meaningful impact for women with gynecologic cancers, where treatment advances have long lagged behind the need."

About the RAINFOLTM -01 Trial
RAINFOL-01 (NCT05579366) is an open-label, multicenter Phase 1/2 study, designed to evaluate the safety and efficacy of rinatabart sesutecan (Rina-S) Q3W at various doses in solid tumors that are known to express FRα. The study consists of multiple parts including Part A monotherapy cohorts; Part B tumor-specific monotherapy dose-expansion cohorts; Part C platinum-resistant ovarian cancer (PROC) cohort; Part D combination therapy cohorts; and Part F a monotherapy endometrial cancer (EC) cohort.

About Endometrial Cancer
Endometrial cancer (EC) ranks as the second most prevalent gynecologic cancer globally, with increasing incidence and mortality ratesv,vi, highlighting the need for effective management strategies. Patients with advanced or recurrent EC have a relatively poor prognosis and treatment options are limited for those patients who have progressed following treatment with chemotherapy and immune checkpoint inhibitor. FRα is overexpressed on multiple tumors, including EC, making it a promising therapeutic target. Anti-tumor activity with Rina-S was observed across a broad range of FRα expression, and there are currently no approved FRα-targeting therapies approved for the treatment of endometrial cancer.

EC starts in the lining of the uterus, known as the endometrium.vii Patients with advanced or recurrent endometrial cancer have a high unmet need. Most (64-74 percent) patients with EC experience disease progression on immune checkpoint inhibitors (ICI) plus chemotherapy irrespective of biomarker status. Treatment options after progression on an ICI-regimen are very limited and consist of single-agent chemotherapy (ORR <16 percent and median progression-free survival [PFS] <5 months).

About Rinatabart Sesutecan (Rina-S; GEN1184)
Rinatabart sesutecan (Rina-S; GEN1184) is an investigational ADC. It is composed of a novel human monoclonal antibody directed at folate receptor α (FRα), a novel hydrophilic protease-cleavable linker, and exatecan, a topoisomerase I inhibitor payload. The clinical trial program for Rina-S continues to expand including ovarian, endometrial and other cancers of unmet need. In January 2024, the U.S. Food and Drug Administration granted Fast Track designation to Rina-S for the treatment of patients with FRα-expressing high-grade serous or endometrioid platinum-resistant ovarian cancer.

Rina-S is advancing through late-stage development, supported by a growing portfolio of Phase 2 and Phase 3 trials, including further evaluation of single-agent Rina-S in patients with advanced endometrial cancer in Part F of the ongoing RAINFOL-01 trial and in a planned Phase 3 trial.

The safety and efficacy of rinatabart sesutecan has not been established. Please visit www.clinicaltrials.gov for more information.

On June 2, 2025 SELLAS Life Sciences Group, Inc. (NASDAQ: SLS) ("SELLAS" or the "Company"), a late-stage clinical biopharmaceutical company focused on the development of novel therapies for a broad range of cancer indications, reported preclinical efficacy of SLS009 (tambiciclib) in ASXL1 mutated colorectal cancer lines. The data are featured in a presentation, entitled "In vitro efficacy of CDK9 inhibitor tambiciclib (SLS009) in ASXL1 mutated colorectal cancer cell lines" at the 2025 American Society of Clinical Oncology (ASCO) (Free ASCO Whitepaper) Annual Meeting, taking place May 30- June 3, 2025, in Chicago, Illinois (Press release, Sellas Life Sciences, JUN 2, 2025, View Source [SID1234653622]).

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In a panel of cell lines, SLS009 demonstrated potent anti-proliferative activity:

In 50% (4/8) of ASXL1 mutant cell lines showed an IC50<100 nM, compared to 0% (0/4) of ASXL1 wild-type lines
Among cell lines harboring ASXL1 frameshift mutations (FSMs), 75% (3/4) responded with IC50 <100 nM versus only 12.5% (1/8) in cell lines without FSMs
All cell lines (3/3) with ASXL1 FSMs in the 637-638 protein region responded to treatment with SLS009
In cell lines with IC50 <100 nM, 75% (3/4) also demonstrated IC99 values below 100 nM, indicating steep dose response curve
Importantly, effective concentrations were significantly lower than those achieved in patients treated at the recommended phase 2 dose determined to be safe, suggesting a broad therapeutic window.
"These results provide strong rationale for continued advancement of SLS009 as a potential treatment for ASXL1-mutated cancers," said Dr. Dragan Cicic, Senior Vice President, Chief Development Officer at SELLAS. "The ability to selectively target ASXL1-driven tumors at concentrations well below the known safety threshold opens the door for tolerable and effective therapy. Based on the findings, we believe that ASXL1 mutation status could serve as a potential biomarker for response to SLS009 inhibition, which may allow us to further refine patient selection and improve outcomes. We look forward to presenting these results at ASCO (Free ASCO Whitepaper)."

Poster presentation details:

Title: In vitro efficacy of CDK9 inhibitor tambiciclib (SLS009) in ASXL1 mutated colorectal cancer cell lines
Session Date and Time: Monday, June 2, 2025, 1:30 PM-4:30 PM CDT
Session Title: Developmental Therapeutics—Molecularly Targeted Agents and Tumor Biology
Location: Hall A – Posters and Exhibits
Abstract #: 3121
Poster Board #: 436

SLS009 is currently being investigated in a Phase 2 open-label, single-arm, multi-center study designed to evaluate the safety, tolerability, and efficacy of SLS009 in combination with venetoclax and azacitidine including AML patients with ASXL1 mutations. Initial clinical safety and efficacy data are available. In addition, the study aims to identify biomarkers for the target patient population and enrichment for further trials. For more information on the study, visit clinicaltrial.gov identifier NCT04588922.