First patients enrolled in Phase I trial with KQB548 (BAY 3771249), an investigational KRAS inhibitor designed to treat KRAS G12D-mutated tumors
KRAS mutations occur in nearly 25 percent of human cancers, with the most prevalent and oncogenic KRAS (G12D) variant still lacking effective treatment options
Innovative drug development candidate strengthens Bayer’s precision oncology development portfolio in the areas of pancreatic, colorectal and lung cancer
Pharmaceuticals
Bayer and Kumquat Biosciences initiate Phase I study with KRAS G12D inhibitor in patients with KRAS-mutated tumors
Berlin, Germany and San Diego, USA, October 8, 2025 – Bayer and Kumquat Biosciences Inc., a clinical-stage biotech company founded by pioneers of targeting the KRAS pathway, announced today the initiation of a Phase I clinical trial with KQB548 (BAY 3771249), an investigational inhibitor designed to treat KRAS G12D-mutated tumors, such as pancreatic, colorectal and lung cancer. The first-in-human, dose-escalation study (NCT07207707) will evaluate the safety and preliminary efficacy of KQB548 (BAY 3771249) as a monotherapy in patients with KRAS G12D mutated tumors. KRAS mutations occur in nearly 25 percent of human cancers, yet the most prevalent and oncogenic KRAS variant (G12D) still lacks effective treatment options.
Initiating clinical development of investigational KRAS G12D inhibitor KQB548 (BAY 3771249) marks an important milestone in our commitment to develop new medicines targeting highly relevant signaling pathways that promote tumor growth and survival. Targeting KRAS has been considered quite challenging. We aim to deliver treatment options for patients with cancers driven by the KRAS G12D mutation. Through continued research innovation we can unlock the potential of precision oncology and improve the lives of people living with cancer.
Dominik Ruettinger, M.D., Ph.D.
,
Global Head of Research and Early Development for Oncology at Bayer’s Pharmaceuticals Division
KRAS G12D mutations are found most frequently in approximately 37 percent of pancreatic ductal adenocarcinoma (PDAC), 13 percent of colorectal cancer and 4 percent of non-small cell lung cancers. These mutations are often recognized as important targets for cancer treatment, and their detection paves the way for the creation of tailored therapies.
Despite recent scientific advancements, there are currently no effective treatments available that provide durable therapeutic benefits for most patients with KRAS-G12D-mutated cancers. Introducing the KRAS G12D inhibitor into clinical trials aims to address the long-standing unmet need.
“We are excited to initiate the clinical trial of our KRAS G12D inhibitor KQB548, which holds the prospect of transforming the KRAS G12D treatments for the deadly malignancies such as pancreatic, lung and colorectal cancers,” said Dr. Nicolas Acquavella, Senior Vice President of Clinical Development and Corporate Alliance Management of Kumquat. “The speedy enrollment highlights our team’s execution capabilities and Kumquat’s long-standing commitment to delivering potentially life-changing medicines to cancer patients.”
About KRAS G12D inhibitor (KQB548 – BAY 3771249)
KQB548 (BAY 3771249) is an investigational KRAS G12D inhibitor being developed to treat KRAS-mutated tumors, such as pancreatic, colorectal and lung cancer. KQB548 (BAY 3771249) is the lead program from the Bayer and Kumquat global exclusive license and collaboration in precision oncology. Kumquat received U.S. Food and Drug Administration (FDA) clearance of the investigational new drug (IND) for its KRAS G12D inhibitor in July 2025.
About Oncology at Bayer
Bayer is committed to delivering science for a better life by advancing a portfolio of innovative treatments. The company has the passion and determination to develop new medicines that help improve and extend the lives of people living with cancer. The oncology franchise at Bayer includes several marketed products across diverse indications and multiple compounds in different stages of clinical development. We have a wealth of expertise in areas including Tumor Cell Intrinsic Pathways, Targeted Radionuclide Therapies, and selective Next-Generation Immuno-Oncology. With our portfolio we are advancing cancer treatments from early to metastatic stage, with the goal of extending survival while limiting side effects for the cancer patients we serve.
About Bayer
Bayer is a global enterprise with core competencies in the life science fields of health care and nutrition. In line with its mission, “Health for all, Hunger for none,” the company’s products and services are designed to help people and the planet thrive by supporting efforts to master the major challenges presented by a growing and aging global population. Bayer is committed to driving sustainable development and generating a positive impact with its businesses. At the same time, the Group aims to increase its earning power and create value through innovation and growth. The Bayer brand stands for trust, reliability and quality throughout the world. In fiscal 2024, the Group employed around 93,000 people and had sales of 46.6 billion euros. R&D expenses amounted to 6.2 billion euros.
About Kumquat Biosciences
Kumquat Biosciences is a privately held drug discovery and development company committed to creating life-changing medicines for cancer patients. The company focuses on translating breakthrough science into first-in-class therapeutics. Kumquat brings together an accomplished team and distinguished scientific founder with a proven track record of innovative oncology drug discovery and development. The company launched in 2019 and was funded by OrbiMed, HSG, EcoR1, Lilly Asia Ventures, Roche Venture Fund, and Boxer Capital, and previously entered two major collaborations with Eli Lilly and Takeda. For more information, please visit www.kumquatbiosciences.com.
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Kumquat Media Contact:
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Email: prnews@kumquatbio.com
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