Armed with first-hand experience in bringing lentiviral vectors to human trials at his prior start-up VIRxSYS Corp., CEO Boro Dropulic launched Lentigen in December 2004 using a two-pronged approach. On the one hand, the company's long term goal is to develop these virus-based drug vehicles into medicines, but Lentigen also aims to become the leading provider of lentiviral products and services. Dropulic estimates that this $10-20 million market can grow by 20% easily. Dropulic spoke with PharmaWeek about his reasons for choosing this path and the company's plan for success.

PharmaWeek: Why are you so committed to this field?

Dropulic: When I first started working with lentiviral vectors, there was reluctance in the field to use them in clinical applications. The field was still so new that there were many important questions. Now, it is more recognized that this is an excellent gene delivery system for research or clinical application. I believe that given the need for highly efficient gene delivery, and the robustness of lentiviral vector technology, vector systems such as ours will become one of the cornerstones of the biotechnology industry.

PharmaWeek: Why do both clinical development and become a product and service provider?

Dropulic: Many companies, including my former company VIRxSYS are focused on therapeutic products. There, we were developing a gene therapy for HIV, and we took such a product into Phase I.  VIRxSYS is presently moving forward its HIV gene therapy product into Phase II trials.  After guiding the company through to the completion of its crucial Phase I clinical trials, seeing the inherent risks of any future clinical trials, and given the single product focus of the company,  I decided to leave VIRxSYS.  I later formed Lentigen which has an entirely different business model that is highly collaborative and which leverages the technology for research and other applications. For example, it can be used as a research tool to understand the function of genes. It can also be used as a manufacturing platform for the manufacture of biologics and vaccines. The research tool service component generates revenues for the company's developmental program.

PharmaWeek: How big do you think this opportunity is?

Dropulic: At present, the lentiviral vector research tool market alone is $10-20 million a year.  Given the enormous interest in integrating RNAi technologies with lentiviral vectors, this market has enormous potential.  Researchers generally want to move  away from transient gene delivery into permanent systems such as lentiviral vectors, which is the most efficient system to generate human cell lines with novel phenotypes. We expect that as much as 20% of the research market for gene delivery and transfection could gravitate to lentiviral vehicles.

So we are building up the research reagent business first. A researcher can presently  come to our Website and build a custom lentiviral vector online, and we'll manufacture it for them. Making lentiviral vectors is an art, and most researchers don't want to spend the time to become expert vectorologists. We standardize the process and provide a highly efficient and pure lentiviral vector preparation.

PharmaWeek: Do you have any big strategic moves planned to put you ahead in this market?

Dropulic: The big strategic move will be when we open up our propriety product line sometime in 2007. We anticipate that will lead to a whole new generation of researchers using this type of vector.

While we have several market opportunities, our competency and company focus is lentiviral vector manufacturing. Right now, nobody is making lentiviral vectors as a contract business, and we are accruing significant IP in this area. Our vector systems and manufacturing process will be cost-effective, robust and commercially scalable.

PharmaWeek: How do you see the clinical research arm of your business evolving?

Dropulic: As with many other technologies, it's going to require a certain amount of time for gene therapy to be commercialized into high value products. Our strategy is not to heavily invest in one particular disease but to collaborate with the top academic and corporate organizations.  Our strategy is to determine which specific products are demonstrating efficacy in pre-clinical and clinical studies before we commit significant resources to a specific disease target.

We currently have ten collaborations with top academic groups, mainly in cancer and regenerative medicine.

PharmaWeek: What are the biggest challenges still ahead for gene therapy

Dropulic: Gene therapy still needs to be optimized. lentiviral vectors will prove to be a highly efficient and robust delivery system for cell gene transfer, but optimizing the clinical regimen will be the remaining challenge. Also, producing lentiviral vectors at a cost that is commercially viable is another challenge. A product that patients can't afford is still a product that brings them no benefit. That is Lentigen's particular focus -  lentiviral vector production using  a robust and economical manufacturing process that is scalable  and with which the FDA will be satisfied.

Of course, gene therapy has also had some setbacks that were very public. Now, all parties are acutely aware that gene therapy clinical trials must be done with the utmost care. But these incidents, such as the death of Jesse Gelsinger, have had a huge impact and will be a constant reminder for all of us in the field. There was also negative publicity for the whole field when some patients developed leukemia linked to gene transfer. But in that case, the vector used was derived from a murine leukemia.  We now have a better understanding how those events occurred and so this will lead to improved vectors with higher safety profiles.  Notwithstanding this, I believe that lentiviral vectors will prove to be fundamentally safer than the murine leukemia virus vector system. Furthermore, Lentigen has licensed a specific class of  genes that will further enhance their safety.

PharmaWeek: Is there another stage to your business model?

Dropulic: Once we have products, in some cases we will be looking for partnerships for their ultimate commercialization.  Our goal would be to validate these therapies in the clinic and work with our partners to bring these therapies quickly to the patients who need them.

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