This is an author correction to an article published in Nature Medicine on May 31, 2026. The correction addresses an error in the Phase 1a dose escalation table in Figure 2, where the fifth dose was incorrectly listed as 0.054 mg instead of the correct value of 0.54 mg. This error was identified and corrected in both the HTML and PDF versions of the article. The article examines the testing of a new TCR-based bispecific T cell engager targeting MAGE-A4 and MAGE-A8 antigens in patients with recurrent or refractory solid tumors. The trial was conducted by multiple German medical institutions and cancer centers. The correction is important for the accurate interpretation of dosing data in the clinical study.