With the advent of cell and gene therapies, “medicine” is changing.
Medicine is at a turning point, where game-changing drugs like aspirin and antibiotics are meeting the new disrupters: gene and cell therapies. We are on the cusp of a major change as scientists reinvent the landscape of therapeutics, and think about using old drugs in new ways.
Cell and gene therapies are still at the research stage, but progressing rapidly toward the clinic. They hold great promise for treating a variety of diseases, both on their own and in combination with more familiar drugs.
Here, we give a brief overview of five classes of medicines: pharmaceuticals, biologics, gene therapies, RNA therapies, and cell therapies. Each one has something different to offer patients, and comes with unique challenges in research and manufacturing.
Intervening at each step of the process
Cells are the basic unit of the human body. They perform countless functions to maintain life, and they complete their tasks using proteins. For example, brain cells communicate with each other by exchanging neurotransmitters, a type of protein. Cells in the pancreas use the protein insulin to control how food gets converted into energy — a process that is disrupted in diabetes.
Cells make proteins in a multi-step process:
- Cells store the instructions for making proteins using genes: sections of DNA sequences.
- DNA gets converted into an intermediary molecule, messenger RNA (mRNA).
- The mRNA is processed into protein.
In patients with disease, specific proteins are not working correctly. Scientists use different classes of medicines to intervene at different steps in the protein-making process:
- Pharmaceuticals and biologics bind to a target protein in order to change how it acts.
- RNA therapies prevent incorrect mRNA from being made into protein, or deliver corrected mRNA for cells to make into protein.
- Gene therapies target DNA sequences, so that cells can make their own source of correct protein.
- Cell therapies replace or modify patients’ cells with ones that make the correct proteins and perform the correct functions.