ANALYST: LIPITOR FOLLOW-ON COULD BE DELAYED BY TRIAL RESULTS
Mixed results from two Phase II clinical trials could delay Pfizer's launch
of its next-generation Lipitor product by as long as two years, according to
a Wall Street analyst.
The trial results, which Pfizer presented recently at the American Heart Association's
(AHA) annual meeting, suggest that while Pfizer's Lipitor (atorvastatin) follow-on,
known as torcetrapib, can dramatically lower cholesterol, it may also cause
hypertension. Patients taking 60 mg of torcetrapib with Lipitor experienced
an increase in systolic blood pressure, Pfizer said. The company said it intends
to further examine the hypertension issues during Phase III studies.
Despite the positive aspects of the studies, including a 41 percent to 60 percent
decline in patients' LDL cholesterol levels, Merrill Lynch analyst David Risinger
said the data could delay Pfizer's launch of torcetrapib.
"We believe Phase II data
indicates that hypertension is an issue
at 60 mg and warrants more conservative approval/launch timing assumptions,"
Risinger wrote in a recent research note. "Previously we assumed a late
2007 approval and early 2008 launch. We now assume FDA will issue an approvable
letter in late 2007, delaying launch to 2010."
Pfizer's first patent on Lipitor is set to expire in September 2009, according
to the FDA's Orange Book. Currently the world's best-selling statin, Lipitor
is expected to generate an estimated $12 billion in revenues this year, according
to analysts.
In addition to the potential setback on torcetrapib, Pfizer reported mixed results
for a clinical trial comparing the effectiveness of Lipitor and Merck's competing
statin drug Zocor (simvastatin), Risinger said.
The Incremental Decrease in End Points Through Aggressive Lipid Lowering (IDEAL)
trial showed that there was no advantage to taking a high dose of Lipitor over
a normal dose of Zocor. The head-to-head study just missed its primary goal
of demonstrating that the higher Lipitor dose was significantly better at reducing
heart attacks and heart-related deaths among patients who have already had heart
problems.
Although Lipitor outperformed Zocor on several fronts, such as lowering cholesterol
and preventing nonfatal heart attacks, Risinger called the IDEAL results "disappointing"
and said Merrill Lynch is revising its Lipitor revenue projections downward.
"We believe this [data] can help insurers and [pharmaceutical benefit managers]
on the margin as they work to push generic Zocor starting in mid-2006,"
Risinger writes. Merck's two patents on Zocor are set to expire in December
2005 and June 2006, according to the FDA's Orange Book.