Exosomes: an opportunity for a new class of biologic therapies

Houman David Hemmati, MD PHD is the Vice President of Medical and Clinical Development for New Therapies at Capricor Therapeutics, Inc. in Beverly Hills, California. In this fascinating talk, he discussed the clinical trials at Capricor and the potential of these biotherapeutics in the pharmaceutical space. Capricor has three platforms: CDCs, Peptide therapy and microRNA exosomes:

The Heart of the Matter

Here they’ve partnered with organ donors to obtain hearts that are not transplantable (may be diseased for instance). They then explant them in tissue culture and get explant-derived cells (EDCs) stem cells which detach and form cardiospheres – little bundles of cardiac stem cells and their derivatives. These are then plated in a dish and where they produce cardiosphere-derived cells (CDCs). In this trial at Children’s Hospital LA, they saw that delivering stem cells to patients post myocardial infarction showed improved healing. 

This is a summary of the trials underway:

These little CDCs pack a punch. They can function as a local drug delivery system (paracrine function), prevent cardiomyocyte apoptosis while promoting cardiomyocyte proliferation and angiogenesis (cell growth and blood vessel formation, respectively). They are also anti-fibrotic, meaning they can prevent or reduce scar tissue. (Note: remember this for skin tissue in the future)

How do they do this? In 2012 they showed as part of their caduceus study that CDCs reduced scar size and increased healthy heart muscle. Not surprisingly, smaller scars have better outcomes. But waiting on donor hearts that aren’t transplanted is not the most viable business model. So they moved to researching exosomes. 

Exosomes


Exosomes are small vesicles (30–150 nm) with a sophisticated RNA and protein profile. They are secreted by all cell types in culture and are found to occur naturally in body fluids, including blood, saliva, urine, CSF, and breast milk. Nanoparticles are not cells so do not have the same challenges faced by cell therapy (ie: fragility, immunologic memory, etc). They can modulate gene expression, transcription and translation while maintaining homeostasis. They clearly carry a future potential in tissue repair. They are a novel, cell-free biologic delivery vehicle with a natural capacity to protect their cargo and get manufactured relatively simply. Look out, there’s a new biotherapeutic in town – and it could be dirt cheap compared with cell therapies.