by almost everyone over the past decade of genomic research, but the company has gained increasing confidence over the past three years that they have evolved to alter signaling pathways for a variety of physiologic processes. These are clearly different processes than those used by existing pharmaceuticals, and they appear relevant to blood disorders (like thrombocytopenia), immune disorders, and metabolic diseases.
This essentially adds an important opportunity for therapies that work in completely new ways, similar to other nascent breakthroughs like microRNA-base therapies and epigenetic-based treatments, Mendlein says. No one knew that tiny microRNAs existed in humans a decade ago, much less had any idea how to make compounds to silence their activity in regulating broad networks of genes. With epigenetics, researchers are looking for ways to control methyl groups that dictate how certain genes are turned on and off, without directly interacting at the level of DNA itself.
From a business standpoint, this is important for a few reasons. There are new proteins that biologists can target, that work differently from other therapies, raising the possibility of what’s called “polypharmacy,” in which patients get multiple drugs that work in different ways to corral a complex disease. It’s also possible that patients could get the aTyr therapy by itself to replace the function of a physiocrine that is lacking in a patient, Mendlein says.
The initial plan is to go after thrombocytopenia, in a bigger and broader way than a couple of big companies have done, Mendlein says. Amgen has had some success with its genetically engineered protein (Nplate) for a rare bleeding disorder called immune thrombocytopenic purpura (ITP). GlaxoSmithKline has tried a different tack against that disease with a small molecule drug eltrombopag (Promacta). Those treatments go after just one narrow form of the thrombocytopenia, but if aTyr’s drug has the kind of broader application the company envisions, it could tap into a much bigger potential market worth $2.5 billion to $4 billion, Mendlein says.
No major drug companies have signed on as partners yet to help aTyr pursue this science and drug development program. Right now, aTyr has a team of 27 people, with 20 of them in San Diego and the rest in Hong Kong. The plan is to keep pushing along methodically with its own programs, although the company may choose to form a partnership, Mendlein says. But he noted that aTyr is in unusually good position, having just completed a venture round that was oversubscribed (meaning aTyr raised more money than it needed to) and that it was an “up round,” meaning the investors placed a higher valuation on the company than they did at previous financings. “We will be weighing our options,” he says.
There are certainly a number of biotech companies out there pushing the edge of innovation in San Diego—Regulus Therapeutics in microRNA and Fate Therapeutics in stem cells to name a couple—but there really aren’t many that have raised significant new venture rounds now that the venture business is essentially facing what many people think is an existential crisis in the wake of the economic downturn. You’d never know it from my conversation with Mendlein yesterday.
“This is back to the basics,” Mendlein says. “High patient needs, new markets, innovative drugs. That’s how a lot of great companies have gotten built.”
