Discovery Labs receives FDA guidance to gain Surfaxin approval for RDS in premature infants

Discovery Laboratories, Inc. (Nasdaq:DSCO) announces today that it has received written guidance from the U.S. Food and Drug Administration (FDA) that is consistent with its ongoing, comprehensive preclinical program to resolve the sole remaining chemistry, manufacturing & control (CMC) issue necessary to potentially gain FDA marketing approval for Surfaxin^® (lucinactant) for the prevention of Respiratory Distress Syndrome (RDS) in premature infants. The safety and efficacy of Surfaxin for neonatal RDS has been previously demonstrated in a Phase 3 clinical program. If approved, Surfaxin would be the first synthetic, peptide-containing surfactant for commercial use in neonatal medicine. Discovery Labs believes it remains on track to complete the preclinical program and submit its Complete Response to the FDA in the first quarter of 2011.

Discovery Labs is now conducting a series of prospectively-designed, side-by-side preclinical studies employing both the newly-optimized and revalidated fetal rabbit Biological Activity Test (BAT, an important quality control release and stability test) and the well-established preterm lamb model of RDS. Discovery Labs plans to complete the preclinical program and submit a Complete Response taking into account the recently-received FDA comments. Multiple Surfaxin batches will be employed in the side-by-side preclinical studies to assess the short-term physiologic response following Surfaxin administration (via measurement of respiratory compliance) in both the preterm lamb model and the optimized BAT. 

The resulting data will be examined to evaluate the relative changes in biologic activity of Surfaxin at several different time points over intended shelf life to determine the degree of comparability between the optimized BAT and the preterm lamb model. The FDA has indicated that, to satisfactorily establish comparability between the optimized BAT and the preterm lamb model, these data must demonstrate the same relative changes in respiratory compliance between both models over time. These studies are intended to also satisfy the FDA regarding the ability of the BAT to adequately discriminate biologically active from inactive Surfaxin drug product and establish the Surfaxin drug product's final acceptance criteria (with respect to biologic activity as assessed by the BAT) for release and ongoing stability. 

Dr. Russell Clayton, Vice President, Research and Development, Preclinical and Regulatory Affairs commented, "Discovery's plan for the potential approval of Surfaxin continues to benefit from the FDA's direction and their recent suggestions have been incorporated into our plan. Another positive aspect of the most recent communication is the FDA's indicated willingness to continue to interact on our approach to gain potential Surfaxin approval." 

In May 2010, Discovery Labs completed a key component of the comprehensive preclinical program, the optimization and revalidation of the BAT, having met all pre-specified acceptance criteria. Prior to optimizing and revalidating the BAT, Discovery Labs had several interactions with the FDA and submitted a proposed revalidation protocol, which also included pre-specified acceptance criteria. Within the next few weeks, Discovery Labs anticipates submitting to the FDA data and analysis from the recently completed optimization and revalidation of the BAT. This information, together with results from the ongoing side-by-side preclinical studies, is expected to be used by the FDA in its review of the planned Complete Response and its ultimate determination on whether to grant marketing approval for Surfaxin.

Discovery Labs believes that it is advantageously positioned to successfully complete the comprehensive preclinical program taking into consideration (i) the revalidation of its optimized BAT (meeting all pre-specified acceptance criteria), (ii) Discovery Labs' experience and relationships with well-recognized academic centers of excellence who routinely measure respiratory compliance in both the BAT and preterm lamb model, and (iii) the FDA's willingness to date to provide continued guidance regarding the Company's plans to resolve the remaining CMC matter.

Surfaxin is an investigational drug candidate that has not been approved by the FDA or any other world health regulatory authority.