Postmarketing surveillance for drug safety
System database and exposure was estimated from IMSAmerica, Ltd, data. The reporting rates of PN (per 100,000
person-years of exposure) are as follows: 25.74 for lefluno-
The recent commentary by Griffin et concerning a
mide, 42.02 for etanercept, 23.67 for infliximab, and 1.01 for
report on peripheral neuropathy and leflunomide patients
methotrexate. The reporting rate for methotrexate is consid-
claims that, as of October 2003, none of the 6 postmarketing
erably lower than that for the newer disease-modifying anti-
studies committed to by Aventis (Bridgewater, NJ) at the time
rheumatic drugs, consistent with the underreporting of events
of approval had been started, at least according to a Food and
that is known to occur with well-established therapies over time.
Drug Administration (FDA) database. In fact, all 6 of these
Since 1998, worldwide patient experience with lefluno-
studies were initiated between 1998 and 2003, and results
mide has exceeded 770,000 patients and has confirmed a
from completed and ongoing studies have been
favorable benefit/risk profile for the treatment of adult pa-
Aventis has performed many postmarketing studies in close
tients with RA. Potential safety signals generated from active
cooperation with regulatory authorities around the world sup-
and intensive postmarketing surveillance have been further
porting the positive benefit-risk profile of leflunomide.
tested and analyzed in large observational cohort studies.
The report by Bonnel and in the same issue raises
Physician and patient information has been continually up-
several methodologic concerns that make the interpretation of
dated to reflect current knowledge about the safety of this
the selective data presented difficult, especially in a rheuma-
The event of interest in the report, peripheral neuropathy,
has been reported during leflunomide treatment in postmar-
keting experience as stated in the prescribing information.
The authors selected events in the FDA database identified as
Global Pharmacovigilance and Epidemiology
peripheral neuropathy occurring in patients treated with le-
flunomide. Peripheral neuropathy was not defined by stan-
E-mail: [email protected]
dardized criteria other than subjective physician assessmentand electrodiagnostic testing, if the latter was available. Spon-
Both authors are full-time employees of Aventis.
taneous report information, the data source for this article, isoften lacking the kind of detail necessary for a complex
References
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I. INTRODUCTION The named End-Payor plaintiffs seek class certification of a class comprised of individual consumers, third-party payors (“TPPs”), union plan sponsors, and insurance companies that purchased or provided reimbursements for Nexium in those states that permit such an action. See Corrected Consol. Am. Class Action Compl. & Demand Jury Trial (“End-Payors’ Compl.”)
Polyploidy in Sugar Beets Induced by the Use of Colchicine, Ethyl Mercury Phosphate, and Other Chemicals1 F R A N K F . L Y N E S A N D C . D . H A R R I S 2 Chemically induced polyploids, particularly those of economic plants, have attracted considerable attention during the past 4 years. Colchicine has been widely used and is now generally accepted as a standard chemical for th