The complex nature of novel biotherapeutic products, like gene therapy, oncolytic viruses, mRNA vaccines, etc., has created significant challenges for an outsourced development approach. There are many concerns to be addressed: external manufacturing capacity, raw materials supply, changing regulatory guidance, evolving technology, and quality concerns. An effective outsourcing strategy must take into account all of these challenges and must be flexible enough to account for changing project requirements. An overview of the complications related to outsourcing challenges in gene therapy and mRNA vaccines as case studies, and suggested approaches, will be discussed in the presentation.