The delay follows last month's pre-NDA meeting between the UK-based pharmaceutical company and the US Food and Drug Administration (FDA), where the agency "unexpectedly" queried one particular undisclosed aspect of the design of the clinical trial programme.
SkyePharma was to submit the NDA in the first quarter of next year but this would now be delayed to the second half of 2008 following the likely need for additional clinical data to resolve the problem.
Speaking to in-PharmaTechnologist.com, SkyePharma chief operating officer Dr Ken Cunningham said he could not comment on the issue needing to be resolved except that it did not relate to the Chemistry, Manufacture and Control (CMC) section, or the safety and efficacy of Flutiform (fluticasone/formoterol), which is still undergoing Phase III clinical trials.
"It's a little disappointing from our point of view that this design issue came up . . . It's something we weren't expecting. But the truth is these things do happen . . . It's not insurmountable," Cunningham said.
It was better the issue arose now rather than after the NDA submission, when the FDA could either send an approvable letter suggesting changes or not approve the product at all, Cunningham said.
While no outline had yet been given by the FDA to resolve the problem, another meeting between the two parties was scheduled for September where guidance would be given and the scope of any additional clinical work detailed.
Should additional clinical data be required, the company estimated the additional net cash cost to the company over the period up to approval would be in the order of £3m (€4.4m) to £5m (€7.4m).
Cunningham said the US setback would not affect the Europe submission of Flutiform, which is expected to be at the end of next year.
Flutiform is a fixed dose combination of a long-acting bronchodilator (formoterol) with the inhaled steroid fluticasone, supplied in the company's proprietary non-CFC metered dose aerosol inhaler equipped with a dose counter.
In May 2006 SkyePharma licensed Flutiform to Kos Pharmaceuticals to market in the US, with an option on the Canadian market. However, six months later US pharma Abbott Laboratories announced its intentions to acquire Kos for $3.7bn, and became the new marketing partner for SkyePharma's Flutiform.
Despite estimated development costs approaching $60m, the company have high hopes for the product as it is poised to enter a large market with relatively limited competition. The only two approved combination drugs are GlaxoSmithKline's Advair/Seretide (salmeterol and fluticasone) and AstraZeneca's Symbicort (budesonide and formoterol), both of which are blockbusters.
The US market for asthma drugs exceeded $10bn (€7.8bn) in 2005 and the fastest-growing segment of this market is fixed combination treatments.
SkyePharma believed Flutiform had the potential to be a $1bn-a-year blockbuster.
