UPDATE: Wyeth Sues FDA Seeking To Reverse Zosyn Approval
September 23 2009 - 11:57AM
Dow Jones News
Wyeth (WYE) has filed a lawsuit against the U.S. Food and Drug
Administration seeking to reverse the agency's recent approval of a
generic version of the company's blockbuster antibiotic Zosyn.
Wyeth claims the generic product can't be safely used in the
same manner as the branded product, due to interactivity with an
intravenous solution sometimes used in conjunction with Zosyn, and
would seriously endanger patients' health. The suit was filed in
U.S. District Court for the District of Columbia.
The FDA last week approved a generic version of Zosyn from
Orchid Chemicals & Pharmaceuticals Ltd. (524372.BY) of India.
Orchid is to have a 180-day period of generic market exclusivity,
and has joined with Apotex Inc. of Canada to sell the drug.
Wyeth, Madison, N.J., had previously asked FDA not to approve
proposed generic versions of Zosyn because they were based on an
earlier formulation of the drug, and Wyeth changed the formulation
in 2005. Orchid's generic product is based on the old
formulation.
The effects of the old formulation of Zosyn can be diminished
when it's given along with an I.V. solution known as Ringer's
lactate, Joseph Camardo, senior vice president of Wyeth's global
medical affairs, said in an interview Wednesday. Wyeth's newer
formulation of Zosyn, however, doesn't have this issue, he
said.
Wyeth fears that medical errors will result if health-care
professionals assume that generic Zosyn is identical to branded
Zosyn and give it with Ringer's lactate, Camardo said.
"We believe [the FDA] came to the wrong conclusion based on the
scientific evidence," Camardo said. "That's why we're asking the
court to force them to reconsider. We think the law is very clear -
if a formulation is different and the ingredients in the
formulation have an impact on the safety and efficacy of the drug,
then you can't consider them identical."
But the FDA said in a letter last week thatthe prescribing label
for Orchid's generic Zosyn will note its incompatibility with
Ringer's lactate. The FDA also stated that the generic is as safe
and effective as Wyeth's reformulated Zosyn when used in accordance
with prescribing labels.
Zosyn had $1.3 billion in sales last year. Wyeth has agreed to
be acquired by Pfizer Inc. (PFE); the deal is expected to close by
the end of the year.
An FDA spokeswoman said the agency doesn't comment on lawsuits.
Zosyn is one of several big-selling branded drugs that have enjoyed
continued market exclusivity even after key patents expired,
largely because their manufacturers had filed citizen petitions
with the FDA asking them not to approve generics. Critics have
accused branded drug makers of abusing the citizen-petition process
to maintain their monopolies, but branded drug makers have said the
petitions were filed for valid safety or efficacy reasons.
Johnson & Johnson's (JNJ) Concerta drug for attention
deficit disorder and Sanofi-Aventis SA's (SNY) Lovenox
anti-clotting drug also have avoided generic competition partly due
to ongoing citizen-petition reviews by the FDA.
Wyeth shares fell 21 cents to $48.33 Wednesday.
-By Peter Loftus, Dow Jones Newswires; 215-656-8289;
peter.loftus@dowjones.com