Flush with $1.5 million from a recent Series A financing round, HistoRx is ready to ramp up its tissue analysis service and to market its platform to pharmaceutical companies and academics.
Navigator Technology Ventures led the investment, which also included Genentech, Sachem Ventures, and Marnat Investments.
Monitoring the expression of individual proteins in tissue sections — as opposed to changes in morphology — is what the Yale University spin-off is all about. The company, which has been operational for a month, offers automated fluorescence-based protein quantification, called AQUA (Automated Quantitative Analysis), in user-defined subcellular compartments of tissue sections.
According to Robert Curtis, HistoRx’s president and CEO, tissue-based quantification of proteins by fluorescence has been difficult in the past for a couple of reasons: the depth of tissues, as well as tissue autofluorescence, has made color analysis of fluorescent markers uninterpretable. Additionally, pathologists have been reluctant to adopt the approach “because they are not really looking at the tissue or cells and are relying on a number,” he said in an e-mail message.
David Rimm and Robert Camp, pathologists at Yale University School of Medicine and HistoRx co-founders, came up with algorithms to overcome the technical problems. For example, by taking multiple images at different depths of the tissue, they were able to calculate the amount and location of fluorescently labeled proteins. HistoRx holds an exclusive license to the technology from Yale, which filed for patent protection several years ago. According to Curtis, Yale has received a “first office action” notice from the US Patent and Trademark office, which means that the application is eligible for patenting, and typically lists action items that must be taken to achieve this.
At the moment, HistoRx can analyze up to three protein markers in parallel, using a custom-made digital imaging microscope that is able to read individual tissue sections or tissue microarrays.
In contrast to other tissue imaging vendors, which include ChromaVision, TriPath Imaging, Ventana Medical systems, and Applied Imaging, HistoRx said it does not use conventional feature extraction-based technologies, which discover differential intensities in the original image. Instead, HistoRx’s algorithms measure probe intensity, which is directly proportional to the number of molecules per area, within user-defined compartments, and does not require differential levels of intensity.
The company, which currently focuses on cancer, is marketing its approach for both pharmaco-diagnostic applications and drug discovery R&D. Regarding the latter, the technology may, for example, help researchers validate potential drug targets. “Understanding which proteins may be elevated or decreased in a particular disease state may give you an understanding of which target to go after,” Curtis said. Also, researchers can evaluate animal models of disease to see if their protein expression patterns resemble those in humans.
HistoRx also has exclusive access to tissue samples in a microarray format for eight types of cancer from Yale University’s tissue archive. The total archive contains three million paraffin-embedded samples, most of them from cancer patients. About half a million of them have up to 40 years of clinical follow-up data associated with them.
In combination with these data, the technology allows researchers to correlate protein markers with disease or treatment outcome, which could help select patients for clinical trials who will likely respond to a treatment, according to Curtis.
This application is where lead investor Navigator Technology Ventures sees the technology’s greatest potential. “It’s our expectation that their techniques will be used in screening patients for specific drugs,” said Alain Hanover, Navigator’s managing director, “and also can be used for rescuing failed drugs [that] addressed the wrong patient population. HistoRx has the possibility of identifying the target population very precisely.”
In the short term, HistoRx is offering its technology both as a research service and licensing it out for research purposes. So far, it has signed up two US-based pharmaceutical companies for its service and has licensed the technology to two “major East Coast biomedical cancer centers,” Curtis said.
HistoRx also plans to develop molecular diagnostic reagents, based on protein markers that are linked to a specific drug treatment. The current funding will “allow us to get up and operate,” Curtis said, and take the company through the next year and a half, “and we think to profitability.”