Sonoran Biosciences Wins SBIR Phase II Award for Sustained-Release Antibiotic Gel to Treat Prosthetic Joint Infections

PJI treatment costs U.S. health system $4 billion annually; grant funds research required to proceed to clinical trials

Sonoran Biosciences logo 300dpi

After about 50 years of academic research and thousands of publications, SB Gel has a chance to be the first material in this family of temperature-responsive polymers used to deliver medications in people.


The company’s SB Gel is an injectable liquid at room temperature that thickens at body temperature, where it conforms to an implant or surgical site surface, slowly releases its drug payload, and then dissolves after the drug is released. The SBIR award will fund the next phase of research required to proceed to clinical trials for a formulation that releases antibiotics for the treatment of prosthetic joint infections.

“After about 50 years of academic research and thousands of publications, SB Gel has a chance to be the first material in this family of temperature-responsive polymers used to deliver medications in people,” said Derek Overstreet, co-founder and chief scientific officer of Sonoran Biosciences. “This generous grant gives us the funding we need to optimize the formulation and commence the safety studies needed to advance our antibiotic product to the clinic.”

Prosthetic joint infections are devastating to patients and costly to the healthcare system. The total costs associated with treatment in the United States are estimated to approach $4 billion in 2016. In the next 10 years, as an aging population increases the number of joint replacement surgeries, the number of associated infections is projected to more than double.

Prosthetic joint infections are caused by bacteria that adhere to implant and tissue surfaces to form a slimy layer called a “biofilm,” which makes the bacteria less susceptible to antibiotics. Treatment requires surgical removal of the vast majority of the infection and very high concentrations of antibiotics for a sustained period of time to kill any remaining biofilm bacteria. Currently, this requires a two-surgery treatment regimen, where the implant and infected surroundings are removed and dosed with an antibiotic-loaded bone cement “spacer,” then the patient is operated on again to replace the spacer with a new permanent implant. The SB Gel formulation is intended to enable treatment in a single surgery by providing high antibiotic concentrations around a new permanent implant, avoiding the need for a spacer.

In early 2016, Joseph Cooper joined Sonoran Biosciences as interim CEO. He connected to the company through the ASU Startup Mill, where he serves as an entrepreneur-in-residence. Cooper previously served as executive vice president for Medicis Pharmaceutical Corporation and in senior roles with Schein Pharmaceutical, Smith and Nephew, and GD Searle.

“The stringent requirements for a Phase II SBIR award constitutes strong validation for the potential of our lead product to provide first-in-class treatment for orthopaedic infections,” said Cooper. “Throughout every phase of Sonoran Biosciences’ development, including this SBIR application, ASU has provided critical support and guidance. We appreciate the work ASU continues to do as we move towards an IND filing and future partnerships and funding of our programs.”

About Sonoran Biosciences
Sonoran Biosciences is a privately held early stage pharmaceutical company that has developed SB Gel, a novel viscous sustained release carrier based on technology developed at Arizona State University. SB Gel enables sustained release of a wide variety of drugs to new sites in the body, including surgical sites, device surfaces, and healing tissues. We develop new formulations using approved active ingredients, requiring reduced development cost and risk while retaining the exclusivity of a typical pharmaceutical. Formulations based on SB Gel have potential in a number of therapeutic areas including infection, pain management, and osteoarthritis. Sonoran’s lead product candidate, SB Gel with a combination of antibiotics, is being developed for treatment of prosthetic joint infection.

Editor’s Note: Research reported in this publication is being supported by the National Institute Of Arthritis And Musculoskeletal And Skin Diseases of the National Institutes of Health under Award Number R44AR070685. The content is solely the responsibility of the authors and does not necessarily represent the official views of the National Institutes of Health.

Posted in AZBio News.