Sanofi, Regeneron prep their PCSK9 cardio contender for FDA review after PhIII sweep

Sanofi ($SNY) and Regeneron ($REGN) are heading to the FDA with a potential blockbuster cardiovascular treatment, touting positive results from a slew of Phase III trials in which the drug slashed patients' bad cholesterol.

The pair plan to submit alirocumab for U.S. and EU approval by year's end, counting on positive data from more than 5,000 patients to make the case for approval. The drug, which blocks the protein PCSK9 to help the body clear LDL cholesterol from the blood, is part of a new class of statin-beating injectables that promise to bring in more than $10 billion at their peak.

In results from 9 Phase III trials, alirocumab successfully lowered baseline LDL cholesterol--the bad variety--in a wide range of patient populations, including those at elevated risk for cardio events, some with statin intolerances and others with a rare genetic disease that predisposes them to high concentrations of blood fat. The antibody was generally well-tolerated across all of the studies, the companies said, with nasal inflammation and respiratory infection the most common adverse events.

Sanofi and Regeneron lag behind rival Amgen ($AMGN) in the race to commercialize the first PCSK9-blocking treatment, with the Big Biotech planning to get its cholesterol-lowering therapy into the FDA's hands in the third quarter after reporting out 9 late-stage studies of its own. Pfizer ($PFE), which is working up a similar treatment, is in the midst of a 22,000-patient Phase III effort and hasn't disclosed a regulatory timeline.

Despite the jockeying for regulatory position, the major differentiating factor among PCKS9 drugs will likely be how well each therapy performs in long-term, outcomes-focused studies. All three antibodies have posted efficacy scores that are likely good enough for the FDA, which accepts lowered LDL cholesterol as a surrogate signal of cardio improvement, but payers may hold out for longitudinal results before agreeing to cover the likely expensive new treatments.

To that end, Sanofi and Regeneron are heralding interim results from a long-term, 2,341-subject study in which alirocumab significantly reduced the risk of heart attack, stroke and other cardio events after one year, suggesting the drug's effect on cholesterol can translate into meaningful outcomes for patients.

Amgen and Pfizer are conducting similar long-term studies of their treatments, expecting to report results in 2017 or 2018.

- read the announcement (PDF)

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