The Pennsylvania-based company said yesterday it has gathered data showing the stability of its drug's process validation and should be ready to send the results this month as part of a formal response to the US Food and Drug Administration's (FDA) approvable letter received in April 2006.
"We have data that demonstrates the stability of our new Surfaxin process validation batches through six months and we have made progress in addressing the chemistry, manufacturing and controls (CMC) issues identified by the FDA so we are confident the regulator will decide our response is complete," said Lisa Caperelli, spokersperson for Discovery Labs.
Once the FDA receives the company's formal response, if it is complete, it will take 10 business days for the agency to give Discovery a Prescription Drug User Fee Act (PDUFA) date after a six-month review.
Caperelli said that in this time frame, Surfaxin could be launched in the first half of 2008 for the prevention of respiratory distress syndrome (RDS) in premature infants.
Surfaxin is a engineered version of natural human lung surfactant which represents a potential alternative to the commercially available animal-derived surfactants.
This latest development represents the end of the company's ordeal with Surfaxin which began in February 2005 when Laureate Pharma, the then contract manufacturer of Surfaxin, received a "483 form" from the FDA alerting it to issues regarding the quality assurances systems, documentation and controls in the manufacturing of the drug.
The regulator then issued a first approvable letter requesting correction of those issues, and when Discovery responded in October 2005, a new PDUFA date was issued in April 2006.
Determined to take the situation into its own hands, Discovery ended its contract manufacturing agreement with Laureate in December 2005 and bought the Totowa facility in New Jersey where Laureate was producing Surfaxin for $16m (€11.2m).
Caperelli explained that the company's goal at the time was to purchase the facility where Surfaxin was made so "it could be in control of the manufacturing" and she said the company remained certain it made the right decision.
"Manufacturing problems with Surfaxin appeared when the product was manufactured by Laureate Pharma but since we were under a contract manufacturing deal with them we assume all the responsibilities regarding the product's quality," said Caperelli.
Discovery Laboratories had been a contract manufacturing client of Laureate Pharma for more than two years, and during 2005 the Totowa facility was primarily dedicated to development of Surfaxin.
However, just before the PDUFA date in April 2006, Discovery received a second approvable letter, this time focusing on the CMC section of the drug application and product labelling.
Another big disappointment for Discovery came on 25 April 2006, when it was announced that one of the process validation batches had failed the six-month stability test required.
In December last year, the company then met with the FDA to clarify some of the key CMC matters identified in the approvable letter and obtain guidance on the appropriate path to potentially gain approval of Surfaxin.
"The FDA's guidance provided a defined pathway for Discovery Labs to generate additional data from selected experiments that are essential for approval of Surfaxin," the company said yesterday.
The drug is also being developed for other neonatal and paediatric indications and Discovery Labs recently initiated a Phase II clinical trial to evaluate the use of Surfaxin in children (up to two years of age) suffering from acute respiratory failure (ARF).