|Discovery Labs and FDA to Discuss Potential Path for SURFAXIN Approval|
|By Staff and Wire Reports|
|Thursday, 10 September 2009 03:00|
At the upcoming September 29 meeting, Discovery Labs plans to discuss with the FDA a limited Surfaxin clinical trial design and whether conducting such trial, while simultaneously employing the fetal rabbit Biological Activity Test (BAT, a quality control and stability release test), could potentially address the key remaining requirement for Surfaxin approval. This approach was suggested by the FDA at the June 2 meeting as a way for Discovery Labs to increase the likelihood of gaining Surfaxin approval. In addition, Discovery Labs plans to review its ongoing quality improvement efforts, intended to further refine the BAT in accordance with Discovery Labs' continuing quality improvement initiatives, with the FDA.
The April 17 Complete Response letter from the FDA and the June 2 meeting focused primarily on certain aspects of the BAT, specifically whether preclinical data generated using both the BAT and a well-established preterm lamb model of RDS adequately supports the comparability of Surfaxin clinical drug product to the to-be-manufactured Surfaxin, and whether the BAT can adequately distinguish change in Surfaxin biological activity over time.
During the conduct of Phase 3 clinical trials for Surfaxin, Discovery Labs employed an array of quality control tests, but did not employ the BAT to evaluate biological activity of the Surfaxin clinical drug product. After completing the Phase 3 clinical trials, in accordance with discussions with the FDA, Discovery Labs validated and implemented the BAT as a recurring quality control test to confirm biological activity for Surfaxin release and stability testing. Based on agreements reached in meetings with the FDA in 2006 and 2008, Discovery Labs conducted a series of preclinical experiments to establish comparability between Surfaxin drug product used in Phase 3 clinical trials and the Surfaxin drug product intended to be manufactured for commercial use. Accordingly, Discovery Labs initiated a series of side-by-side studies employing both the preterm lamb model of RDS and the BAT and believes that the correlated results demonstrate comparability and support approval of Surfaxin.
At the June 2 meeting with the FDA, Discovery Labs presented data from the preterm lamb model and BAT studies, together with a comprehensive statistical evaluation of such data, intended to establish the comparability of clinical drug product to Surfaxin drug product to be manufactured for commercial use. The comprehensive statistical evaluation was a comparative regression analysis using an accepted FDA statistical method. Discovery Labs believes that the data and related statistical evaluation are highly supportive of the comparability of clinical drug product to commercial Surfaxin.
However, the FDA stated at the June 2 meeting, that data generated from the preterm lamb model and BAT studies must demonstrate, in a point-to-point analysis, the same relative changes in respiratory compliance between both models over time. Based on this standard, Discovery Labs believes that establishment of comparability in this manner would be an extremely high hurdle and that, from the FDA's perspective, the data analysis provided by Discovery Labs did not meet that standard.
In addition, the FDA suggested that the comparability studies in the preterm lamb model and the BAT would not be necessary if the BAT had been implemented to assess Surfaxin drug product used in the Phase 3 clinical trials. The FDA also suggested that, to increase the likelihood of gaining Surfaxin approval and as an alternative to demonstrating comparability using the preterm lamb model and BAT, Discovery Labs could consider conducting a limited clinical trial, while simultaneously employing the BAT, as a path forward to Surfaxin approval.