BRIAN MULLAN
Yposkesi, an SK pharmteco Company, Paris (Corbeil-Essonnes), France

Abstract

Cell and gene therapies (C&GT) are a fast growing and promising class of medicines that offer the possibility of curing conditions with a genetic basis that have few or no other therapeutic options for patients. From a turbulent start in the 1990s, with some notable setbacks in clinical trials, the promise of these therapies has now become a reality, with numerous market approvals in recent years, a robust clinical pipeline and strong industry and investor interest. The sector is both immature, from the regulatory and CMC perspectives, and growing fast. Numerous challenges will need to be surmounted in the coming years to ensure that these therapies can reliably reach patients, but the future looks very promising.

INTRODUCTION: WHAT ARE CELL AND GENE THERAPIES?
Cell and Gene Therapies (C&GT) are a growing category of medicines that enable genetic defects to be directly corrected in patients, thus enabling remediation of disease symptoms that typically have no other therapeutic option (1). Some of the diseases treated by C&GT have existing small or large molecule therapeutic options (e.g., Spinraza (2) from Biogen/Ionis for Spinal Muscular Atrophy, SMA, which can also be treated by the C&GT Zolgensema (3) from Novartis), but for many of the target conditions C&GT often represents the only treatment option for patients.

C&GT work by providing a functioning / non-defective copy of a gene directly to the patient, which can enable the relevant underlying biology to function correctly, thus remedying the symptoms caused by the genetic defects (1).

As such, these therapies provide a cure, as opposed to an ongoing treatment. There is also a growing sub-category of C&GT products based on gene-editing approaches (4), whereby the C&GT can repair or edit the defective gene, as opposed to substituting it.