GMP manufacturing of cell and gene therapy products: Challenges, opportunities, and pathways forward.

Cell and gene therapy (CGT) products have been emerging as life-saving and life-changing therapies over the last 20 years. The United States has been a forerider in the development of these therapeutic products and has also developed the pertinent manufacturing methods for these complicated "living medicines." California has emerged as a prominent hub for CGT manufacturing, hosting a variety of good manufacturing practice (GMP) facilities. These facilities are pivotal in advancing CGT products from phase 1 to phase 3 clinical trials and, eventually, to commercialization. Despite California's strategic advantages, including its biotech ecosystem and access to venture capital, numerous challenges hinder its full potential. These include funding disparities, expertise limitations, stringent regulatory demands, and a mismatch between facility utilization and demand. This review explores these factors more in depth and provides a comprehensive analysis of the current state of GMP manufacturing for CGTs in California. The example of the current situation in the state of California may also serve as an analogy for other states; we chose California due to our decades of experience manufacturing CGT products in this state.