AbbVie steps closer to FDA filing as first hep C PhIII delivers promising results

With Gilead's ($GILD) pioneering hepatitis C drug sofosbuvir moving closer to a likely approval and a megablockbuster market, AbbVie is looming from behind with some promising results from the first of 6 Phase III studies of its breakthrough triple-threat therapy. And AbbVie is vowing today that the successful late-stage effort sets the stage for a regulatory filing in the second quarter of 2014.

AbbVie's ($ABBV) all-oral "3D" regimen scored high sustained virological response rates among 631 treatment-naive patients after 12 weeks of treatment, hitting 96% for the treatment arm. The patients were all in the hard-to-treat genotype 1 category, with SVR rates of 95% and 98% for GT1a and GT1b patients. The discontinuation rate was low, only 0.6%, with a 1.7% relapse rate.

AbbVie's 3D approach--which includes ABT-450/r + ABT-267 + ABT-333--is expected to help terminate the use of interferon injections for hepatitis C patients, who will cheer its extinction. A number of companies, including Gilead and Bristol-Myers Squibb ($BMY), are racing through late-stage programs with their own pieces of this combination puzzle, with new cocktails coming along that will introduce a new standard of care for the disease.

The FDA has provided its breakthrough therapy designation to AbbVie's program, promising to accelerate the review process as analysts project about $3 billion in potential annual sales. That's well behind projections for sofosbuvir, but the money would go a long way to breaking AbbVie's reliance on Humira as its sole big earner.

An approval would also be a big boon for Watertown, MA-based Enanta Pharmaceuticals ($ENTA), which provided the protease inhibitor ABT-450 for the combo. But some analysts have been cautious about their competitive position in this busy field.

"While ABBV's cure rate data continues to be very impressive, the number of pills may be an issue from commercial front," notes ISI's Mark Schoenebaum. "For instance, Gilead's G1 regimen is simply one pill once a day. ABBV's SAPHIRE-1, on the other hand, employed: Coformulated PI + NS5a + ritonavir - once a day; non-nuc - twice a day; ribavirin - twice a day."

"SAPPHIRE-I demonstrates that patients new to therapy with genotype 1 HCV achieved high rates of virologic response with AbbVie's interferon-free, all-oral 3D regimen plus ribavirin, and the SVR rate is consistent with results from our phase II studies," said Dr. Scott Brun, vice president, pharmaceutical development, AbbVie. "SAPPHIRE-I is the first of these studies to report results, and based on the progress of our clinical program to date, we are on track for major regulatory submissions in the second quarter of 2014."

- here's the press release