Animal study showing cartilage regeneration with BST-CarGel®

Clinical trial ongoing.

Focalized cartilage lesions occur in patients as a result of trauma, injury or excessive physical activity or those suffering from “secondary osteoarthritis” (OA). Adult articular cartilage does not have the capacity to repair such structural damage. This limited healing potential arises primarily due to a lack of blood supply and an inadequate response by repair cells. The resulting joint pain and loss of mobility is debilitating for millions of people worldwide.

In many cases, treatment of either acute or chronic focal cartilage injuries involves use of various surgical measures aimed at regenerating cartilage in the damaged area. Bone marrow stimulation (e.g. microfracture), mosaicplasty and autologous chondrocyte implantation are several techniques which are currently used but still have inherent drawbacks.

BST-CarGel® is a promising new therapeutic approach for repair of localized cartilage lesions.

BST-CarGel® is mixed at the time of surgery with the patient’s own blood and applied during minimally-invasive surgery to the surgically prepared lesion. Our animal studies have shown that BST-CarGel® fills and sticks to the cartilage lesion, where it acts as a 3-dimensional scaffold in what is called Scaffold-Guided Regenerative Medicine (SGRM). Due to the chitosan component and its unique tissue-adhesive nature, the residency of BST-CarGel® is maintained. And because the repair of the cartilage occurs within the body, and not in a laboratory, it is termed In Situ ChondroInduction (ICI). The ICI approach offers interesting benefits, as it requires only one surgery and simply guides the repair of the damaged cartilage. Our animal studies have demonstrated that during the regeneration process, BST-CarGel® is completely degraded, as the cartilage naturall y regenerates, which results in dramatically improved cartilage repair over matched controls.

Pivotal Trials for the BST-CarGel®

On February 2, 2009, the Corporation announced that it had achieved a key product development milestone, the completion of enrolment for the Canadian-European pivotal trial of its cartilage repair device BST-CarGel®, by reaching the planned objective of enrolling 80 subjects into the randomized trial. The trial was designed to study the repair capabilities of BST-CarGel® applied following microfracture against the treatment of microfracture alone.

On March 12, 2009, the Corporation announced that it would conduct an interim analysis of the available clinical data from 40 subjects who have completed their 12 month follow-up in the 80 subject trial for BST-CarGel®.

On June 17, 2009, the Corporation announced positive results from an analysis of patients who completed their 12 month follow-up in its BST-CarGel® randomized clinical trial. According to the analyses performed on tissues biopsied from the knees of 22 patients, treatment of cartilage lesions with BST-CarGel® produced statistically significant evidence of improved repair tissue quality. These findings are initial results of a subset component of this interim analysis. The results for the interim analysis of the available clinical data from 40 subjects enrolled in its Canadian-European pivotal trial are now expected to be available towards the end of calendar year 2009, and the final clinical results of the 80-patient study are now anticipated in the summer of calendar year 2010.