Instead of a traditional chemotherapy comparison, Divarasib's registrational study is a head-to-head trial against approved KRAS G12C inhibitors. This trial design reflects a strategic shift towards proving superiority within a new drug class, not just efficacy against older standards of care.

Direxonrasib is showing unprecedented response rates (e.g., 47% in frontline) for metastatic pancreatic cancer, a historically difficult-to-treat disease. This high performance prompts comparisons to the targeted therapy successes seen in lung cancer, signaling a potential paradigm shift in treatment expectations for PDAC.

The KRAS G12D mutation, unlike the more common G12C, often occurs in younger, never-smoking lung cancer patients who previously lacked targeted therapy options. The high response rate (61%) and good tolerability of the G12D inhibitor Zoldanrasib could fill a significant unmet need in this specific demographic.

The GSK3 inhibitor was developed for CNS diseases, requiring high specificity and the ability to cross the blood-brain barrier. These same pharmaceutical characteristics—potency and lipophilicity—proved highly advantageous for treating cancer, demonstrating an unexpected but effective therapeutic pivot from neuroscience to oncology.

With new CNS-active drugs dramatically improving survival after a brain metastasis diagnosis, some experts are now advocating for routine screening brain MRIs in high-risk patients. The goal is to detect asymptomatic lesions early, potentially preventing catastrophic neurologic events like seizures.

Actuate’s drug was designed to be highly lipophilic (fat-soluble) to cross the blood-brain barrier for CNS treatment. This same property proved crucial for its success in oncology, as it allows the drug to easily penetrate cancer cell membranes and reach the nucleus.

While the avutometanib/defactinib combination is newly approved for KRAS-mutated ovarian cancer, its significant toxicity profile—causing up to a third of patients to stop treatment—creates a clear clinical need for agents like specific KRAS inhibitors that may offer similar efficacy with better tolerability.

The development of new KIT inhibitors like bezuclastinib is largely fueled by the need for alternatives to high-dose avapritinib in advanced SM. Concerns about cognitive effects and rare intracranial hemorrhage with avapritinib create an opportunity for agents with less blood-brain barrier penetration.

Unlike the intact blood-brain barrier, the blood-tumor barrier within brain metastases is permeable. This "leakiness" allows large molecules like the ADC trastuzumab deruxtecan (TDXD) to enter and deliver its payload, providing a mechanism for its high CNS efficacy.