Carbylan BioSurgery

Carbylan Therapeutics was a clinical-stage specialty pharmaceutical company focused on developing therapies for pain associated with osteoarthritis of the knee. The company was founded in 2004 as Sentrx Surgical, Inc., became Carbylan BioSurgery, Inc. in December 2005, and was finally renamed Carbylan Therapeutics, Inc. in March 2014.

The company's core technology involved the crosslinking of hyaluronic acid to form hydrogels, which could be combined with other pharmaceutical agents. Its lead product candidate was Hydros-TA, an intra-articular injectable that combined a low-dose corticosteroid with a proprietary hyaluronic acid viscosupplement. This formulation was designed to provide both immediate and long-term pain relief. The business model centered on advancing this product through clinical trials to gain regulatory approval and commercialize it for the significant market of patients with osteoarthritis pain.

Carbylan was venture-backed, with investors including InterWest Partners, Alta Partners, and Vivo Capital. The company went public in April 2015, raising approximately $74.6 million in net proceeds after an initial postponement. However, in February 2016, its Phase III clinical trial for Hydros-TA failed to meet one of its primary endpoints. This setback led the company to halt further development of the drug in April 2016, reduce its workforce by 14 of its 17 employees, and seek strategic alternatives, including a merger or acquisition.

In June 2016, Carbylan entered into a definitive agreement to merge with KalVista Pharmaceuticals, a private biopharmaceutical company. The reverse merger was completed in November 2016, and the combined entity was renamed KalVista Pharmaceuticals, Inc., trading under the NASDAQ symbol "KALV". The new company shifted its focus to KalVista's pipeline of small molecule protease inhibitors for diseases like hereditary angioedema (HAE) and diabetic macular edema (DME).

Keywords: osteoarthritis pain, hyaluronic acid, injectable therapies, drug development, clinical trials, hydrogel, biopharmaceutical, specialty pharmaceutical, viscosupplement, corticosteroid combination, reverse merger, Hydros-TA, Sentrx Surgical, KalVista Pharmaceuticals, acquired, defunct, CBYL, knee pain relief