Biological therapies (BTs) refer to using live creatures or compounds produced from living organisms to cure illness. BTs are effective in treating a variety of diseases, such as cancer, rheumatoid arthritis, psoriasis, and inflammatory bowel disease among others. Monoclonal antibodies, vaccine therapies, cytokine therapies, gene therapies, dendritic cell-based therapies, adoptive T-cell therapies, oncolytic virus therapies, RNA oligonucleotide therapies, and DNA oligonucleotide therapies were among the most often utilized biological treatments for cancer therapy. Additionally, stem cell therapy, tissue engineering 3D bioprinting, and phytochemicals have attracted attention in recent decades. However, due to their high cost, there are huge disparities in their use internationally, in addition to some social or religious norms that may be one of the obstacles to the use of BTs. This chapter explores the Halal implications of biological therapies in medicinal chemistry, particularly in stem cell therapy, gene modification, and vaccine production, and their compliance with Islamic principles.