Trastuzumab pamirtecan results

An antibody-drug conjugate works like a guided package: an antibody finds a tumor marker, then delivers chemotherapy into the cancer cell. In advanced endometrial cancer, trastuzumab pamirtecan posted a confirmed response rate near 50% in new Phase 2 data presented April 11 in San Juan, Puerto Rico. (biospace.com) The drug targets HER2, a protein found at varying levels on some endometrial tumors. In the global Phase 1/2a trial, the endometrial cancer cohort included patients whose disease had progressed after first-line chemotherapy, with or without prior immune checkpoint inhibitor treatment. (clinicaltrials.gov) In patients whose tumors were confirmed as HER2-expressing by central testing, the confirmed objective response rate was 47.9% across 96 evaluable patients. Median progression-free survival was 8.1 months, and median duration of response was 11.1 months. (onclive.com) Among 73 centrally tested patients who had already received an immune checkpoint inhibitor, the confirmed objective response rate was 49.3%. Disease control in that subgroup was 79.5%, and median duration of response was 9.9 months. (targetedonc.com) The company and investigators said activity was seen across HER2 expression levels, including tumors with lower HER2 staining. OncLive reported responses were higher in the HER2 3+ group, topping 70% by central testing. (biospace.com) (onclive.com) That matters in this disease because treatment choices narrow quickly after recurrence. The National Cancer Institute says recurrent endometrial cancer is treated with systemic options such as chemotherapy, hormone therapy, immunotherapy, targeted therapy, radiation, or surgery depending on the case, and outcomes are generally worse once the cancer has spread or returned. (cancer.gov) The disease burden is also moving in the wrong direction. The American Cancer Society says endometrial cancer is one of the few cancers with rising mortality, with the U.S. death rate increasing 1.6% per year from 2014 to 2023. (cancer.org) Safety is part of the story with this drug class because the “payload” can still hit healthy tissue. Investigators said the safety profile was manageable and in line with similar drugs, with gastrointestinal side effects mostly low grade, while interstitial lung disease and pneumonitis remained risks that require monitoring. (targetedonc.com) Regulators are already moving this program faster. OncLive reported the Food and Drug Administration has granted breakthrough therapy designation for this endometrial cancer indication, and BioNTech said the confirmatory Phase 3 trial Fern-EC-01 is already enrolling patients against physician’s-choice chemotherapy. (onclive.com) (biospace.com) For now, the Phase 2 readout shows that a HER2-directed drug carried by an antibody produced durable tumor shrinkage in a heavily pretreated endometrial cancer group. The next test is whether the larger randomized study can show it beats standard chemotherapy in the same setting. (biospace.com)