Immunotoxin Therapy: A Promising Frontier in Targeted Cancer Treatment a Review of Clinical Trials in Hematological and Solid Tumors

Background and objective Background and objective: Cancer is a leading cause of death worldwide, creating a major socioeconomic burden. Despite advances in conventional therapies, mortality remains high, highlighting the need for more effective, targeted treatments. This review critically examines immunotoxin therapy as a promising approach, focusing on its evolution from experimental agents to clinical development, including design, mechanisms of action, and therapeutic potential. Methods We conducted a structured review of immunotoxins currently under clinical investigation for both hematological and solid malignancies. The analysis compares different immunotoxin constructs, their targeted antigens, and outcomes from recent and ongoing clinical trials. Results Immunotoxins, engineered by fusing a targeting moiety (e.g., an antibody fragment) with a potent protein toxin, have shown significant efficacy, particularly in hematological tumors. The review details key immunotoxins in the clinical pipeline, discussing their successes, such as high response rates in certain leukemias and lymphomas, as well as the critical challenges they face. These challenges include immunogenicity, off-target toxicity, and the development of drug resistance, which have limited their efficacy in solid tumors. Conclusion Immunotoxins represent a powerful class of targeted anticancer agents. While obstacles remain, ongoing innovations in protein engineering to reduce immunogenicity and improve tumor penetration are poised to enhance their clinical utility. With continued advancement, immunotoxins are expected to play an increasingly vital role in the future of precision cancer therapy.