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Drug delivery is becoming an increasingly important part of the drug development process, a fact that bodes well for start-up Carigent Therapeutics Inc., which offers a nanoparticle-based delivery system designed to provide targeted and controlled-release drug delivery to tissues and cells.

The New Haven, Conn.-based firm was founded by Mark Saltzman, Tarek Fahmy and Peter Fong, all of Yale University, who developed the technology for encapsulating high drug loadings into polymer particles on the nanoscale. Though nanoparticle delivery methods are not new, Carigent's founders were able to invent a system that "solves a number of long-standing historical problems," said Seth Feuerstein, president and company co-founder.

Difficulties have included finding efficient ways to attach drug payloads to the surface of nanoparticles for controlled-release and making sure that sufficient density of the drug is attached. Saltzman, Fahmy and Fong were able to figure out a way to attach the drug at a "very high density," Feuerstein said, adding that the technology offers a lot of flexibility.

"It can deliver siRNA drugs to small molecules and can do it in a targeted way, with a higher concentration of target material on the surface," he told BioWorld Today. "That's where the power lies."

Carigent's technology is able to target drugs to specific cell types, so any toxicity from the drug is limited to the disease site and bypasses healthy cells and tissues, and allows for the easy attachment of PEG to increase a drug's half-life. The multifunctional engineered nanoparticles are designed using FDA-approved PLGA, a polymeric material already used in controlled drug delivery formulations.

The company's business strategy is twofold. On its own, Carigent is developing a pipeline of existing drugs delivered via its nanoparticle technology. "We're taking drugs that are known to work but are limited" due to toxicity or lack of efficacy, Feuerstein said, with an initial focus on oncology. He added that Carigent received grant funding to target ovarian cancer and non-Hodgkin's lymphoma.

The second part of the firm's strategy involves collaborating with partners to develop second-generation product candidates. Feuerstein said Carigent already is working in that area, though specific details remain confidential at this time.

Most recently, the company, which employs a total of seven people, raised $2 million in its first round of private financing provided by Saint Simeon Marketing and Investments Lda. Those Series A funds will support the further development of the nanotechnology platform and its internal pipeline, and also will help the firm improve laboratory production capabilities and build partnerships.

Over the next year, Carigent aims to "generate a significant amount of preclinical data for our first product," Feuerstein said, as well as cultivate additional partnerships, and hopefully, including a full partnership by year-end.

Those certainly are realistic expectations. With fewer new drug approvals in 2007 compared to previous years - as the FDA treads every more carefully following safety issues arising from marketed drugs such as Vioxx - many companies have started to look at alternative drug delivery methods that could offer increased safety and greater efficacy. It's definitely a part of the industry that "is coming into its own," Feuerstein said.

New delivery methods might even prove vital to firms that have watched their drugs fail in the clinic, in spite of promising efficacy in the lab, because they could not be delivered adequately or in sufficient amounts to yield a response. A different delivery method, such as Carigent's nanoparticle-based technology, could make all the difference.

"We're finding that people are very open to those discussions," Feuerstein said. "We've also heard from companies looking at creating a second-generation product" with a different delivery system.

"They realize that the market opportunity would be better if the [drug] had better dosing and higher bioavailability."