Brightline-2: a phase IIa/IIb trial of brigimadlin (BI 907828) in advanced biliary tract cancer, pancreatic ductal adenocarcinoma or other solid tumors.

Mouse double minute 2 homolog (MDM2) is a key negative regulator of the tumor suppressor p53. Blocking the MDM2-p53 interaction, and restoring p53 function, is therefore a potential therapeutic strategy in MDM2-amplified, TP53 wild-type tumors. MDM2 is amplified in several tumor types, including biliary tract cancer (BTC), pancreatic ductal adenocarcinoma (PDAC), lung adenocarcinoma and bladder cancer, all of which have limited treatment options and poor patient outcomes. Brigimadlin (BI 907828) is a highly potent MDM2-p53 antagonist that has shown promising activity in preclinical and early-phase clinical studies. This manuscript describes the rationale and design of an ongoing phase IIa/IIb Brightline-2 trial evaluating brigimadlin as second-line treatment for patients with advanced/metastatic BTC, PDAC, lung adenocarcinoma, or bladder cancer.

Brightline-2: a phase IIa/IIb trial of brigimadlin (BI 907828) in advanced BTC, PDAC, or other solid tumorsIn some types of cancer, including cancers of the bile duct, pancreas, bladder and lung, the number of copies of a gene called MDM2 is abnormally increased (MDM2 amplification). MDM2 usually regulates p53, a protein that stops cancer cells from growing uncontrollably. When MDM2 is amplified, the cell makes too much of the MDM2 protein, which prevents p53 from stopping cancer growth. Blocking the interaction between MDM2 and p53 may allow p53 to do its job again and stop cancer cells from growing.Brightline-2 is a clinical trial that is currently in progress. This trial is assessing the efficacy and safety of an investigational drug, brigimadlin (or BI 907828), in patients with selected advanced or metastatic cancers. To be included, patients must have advanced biliary tract cancer, pancreatic ductal adenocarcinoma, bladder cancer, or lung adenocarcinoma. The tumor must show amplification of MDM2 when tested by a laboratory. Patients will take a 45 mg tablet of brigimadlin by mouth, once every 3 weeks. In this trial, researchers are investigating the ability of the drug to shrink tumors, the side effects of the drug, and the impact of the drug on a patients' quality of life.The goal of this trial is to assess the potential of brigimadlin as a new treatment option for patients with advanced biliary tract cancer, pancreatic ductal adenocarcinoma, bladder cancer, or lung adenocarcinoma.Clinical Trial Registration: NCT05512377 (ClinicalTrials.gov).

Treatment options for biliary tract cancer: unmet needs, new targets and opportunities from both physicians' and patients' perspectives.

Biliary tract cancer (BTC) is a rare cancer with poor prognosis, characterized by considerable pathophysiological and molecular heterogeneity. While this makes it difficult to treat, it also provides targeted therapy opportunities. Current standard-of-care is chemotherapy ± immunotherapy, but several targeted agents have recently been approved. The current investigational landscape in BTC emphasizes the importance of biomarker testing at diagnosis. MDM2/MDMX are important negative regulators of the tumor suppressor p53 and provide an additional target in BTC (∼5-8% of tumors are MDM2-amplified). Brigimadlin (BI 907828) is a highly potent MDM2-p53 antagonist that has shown antitumor activity in preclinical studies and promising results in early clinical trials; enrollment is ongoing in a potential registrational trial for patients with BTC.

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Efficacy and Safety of the MDM2-p53 Antagonist Brigimadlin (BI 907828) in Patients with Advanced Biliary Tract Cancer: A Case Series.

Background: In patients with advanced biliary tract cancer (BTC), first-line chemotherapy plus immunotherapy has improved outcomes; however, second-line options that reflect the disease's molecular heterogeneity are still needed. One emerging target is MDM2, amplified in ~5-8% of BTC cases. Methods: This is a subset analysis of two ongoing Phase Ia/Ib trials assessing patients treated with brigimadlin (BI 907828; a highly potent, oral MDM2-p53 antagonist) ± ezabenlimab (PD-1 inhibitor) ± BI 754111 (anti-LAG-3; n = 1). Results: Results from 12 patients with BTC are shown (monotherapy: n = 6/combination: n = 6). Six patients achieved partial response (monotherapy: n = 2/combination: n = 4), four had stable disease; responses were durable. Brigimadlin had a manageable safety profile. Seven patients had dose reductions due to adverse events, but no treatment-related adverse events led to treatment discontinuation. Conclusion: Brigimadlin demonstrated anti-tumor activity in patients with advanced MDM2-amplified BTC, and warrants further investigation.

Biliary tract carcinoma (BTC) is a cancer that affects the bile ducts which are part of the digestive system. Usually, the first treatment for advanced BTC (ie cannot be removed surgically and/or has spread) is chemotherapy in combination with immunotherapy. However, if chemotherapy does not work, or stops working, there are few treatment options available in second-line. Accordingly, intensive research is ongoing to try and find effective drugs. One potential medicine, called brigimadlin (or BI 907828), is a tablet that activates a molecule in tumor cells called p53. The normal function of p53 is to kill cells when they first start to become cancerous. However, if p53 is turned off by genetic mutations, or other mechanisms, then cancer can develop. Although p53 is rarely mutated in BTC tumors, it is inactivated by another molecule called MDM2 which is usually present at abnormally high levels in BTC. Brigimadlin prevents interaction between MDM2 and p53. This activates p53 and causes the cancer to die. Two clinical trials are currently assessing brigimadlin in a range of cancers, including BTC, with the aim of identifying a safe dose that can be examined in more detail in larger trials. So far, 12 patients with BTC have been treated. The patients' tumors significantly shrank in six of these patients and remained stable in a further four patients. Side effects were as expected and could be tolerated by pausing treatment or lowering the dose. These results show that brigimadlin should be tested further in patients with advanced BTC.