The article discusses the impact of upcoming patent expirations in oncology biologics on biosimilar developers, highlighting the opportunities in Antibody-Drug Conjugates (ADCs) and Bispecific Antibodies (BsAbs). It explores the challenges posed by the structural complexities of these biologics, necessitating new bioanalytical tools and manufacturing processes. The evolving regulatory landscape, with contributions from EMA, FDA, and WHO, offers flexible pathways but also presents challenges. The article underscores the potential for biosimilars to generate significant cost savings and enhance patient access to cancer treatments over the next decade.