Drug Delivery Challenge
While many drugs show strong potential in the treatment of cancer and other diseases, the methods and environments in which they are administered may limit localized penetration and thereby their ability to function. Often this is inherent to the structure and function of the tissue or surface being targeted, which may be designed as a barrier to absorption (e.g. the urothelium in the bladder). Therapeutically, this can lead to the administration of high concentrations of a drug, which even still may not lead to sufficient localized concentrations and can result in significant systemic exposure. Alternatively, systemically administered drugs may be chosen, bringing all of the attendant issues of unnecessary exposure to non-diseased tissues and those side effects.

Improving Local Drug Administration and Tissue Penetration
Sitka Biopharma’s patented polymeric nanoparticle platform technology is specifically designed to increase penetration, absorption, and retention of drugs in difficult-to-penetrate tissues. Constructed of hyperbranched polyglycerol (HPG), our technology offers unique benefits over other nano-delivery systems, including:

  • unimolecular polymer: non-aggregate, non-dynamic structure yields a stable formulation under diverse conditions
  • small nanoparticle size (8-10 nm) and low viscosity: allows high degree of access to large/complex tissue surfaces
  • ability to alter hydrophobic core/hydrophilic shell ratio to suit incorporation of various classes of drugs
  • additional surface functionality: mucoadhesive moieties can be engineered onto the outer layer of the polymer to alter initial tissue adsorption, chelation sites for addition of other molecules

Product Development
At Sitka Biopharma, we are currently focused on developing novel products by combining our HPG nanoparticle technology with established drugs. Our lead program, STK-01, aims to improve efficacy and tolerability of treatment for non-muscle-invasive bladder cancer.

Our technology is highly versatile, has potential utility for a wide variety of indications, and is particularly well-suited for treating relatively localized diseases where local administration of the therapeutic is possible but is currently ineffective or unsafe. We welcome opportunities to collaborate with biopharmaceutical companies that wish to take advantage of our HPG nanoparticle technology.