The FDA, the Patch, and Risk

The other day I posted about the issue of accurate reporting of an FDA labeling update for the patch. Here is a report more to my liking:

The U.S. Food and Drug Administration (FDA) approved new labeling today regarding the increased level of estrogen exposure associated with use of an ethinyl estradiol/norelgestromin transdermal system (Ortho Evra, made by Ortho McNeil Pharmaceuticals, Inc.) compared with most oral contraceptives.

The warning was based on the results of pharmacokinetic studies showing that steady-state [base line] levels of ethinyl estradiol were increased by 60% in patch users compared with those taking once-daily oral contraceptives containing 35 µg of estrogen. However, use of the transdermal patch also yielded a 25% decrease in maximal exposure.

Although use of the weekly patch may reduce the risk of pregnancy in women who are noncompliant with a daily oral contraceptive regimen, the FDA advises that the potential risks of increased estrogen exposure (eg, thrombotic adverse events) be considered prior to use of the product.

The FDA notes that it remains unclear whether women using the patch are at higher risk for serious adverse events compared with those taking oral contraceptives.

Further information regarding the ethinyl estradiol/norelgestromin transdermal contraceptive system may be obtained by contacting the FDA Division of Drug Information at 1-888-INFO-FDA (1-888-463-6332), or by sending an email to druginfo@cder.fda.gov.

Adverse events related to the use of the contraceptive patch devices should be reported to the FDA's MedWatch program by phone at 1-800-FDA-1088, by fax at 1-800-FDA-0178, online at http://www.fda.gov/medwatch, or by mail to 5600 Fishers Lane, Rockville, MD 20852-9787.

Not only is the report clear and factual, but, and this is a big plus, the article has information on how to report an adverse event. The one small criticism I have concerns this paragraph:

Although use of the weekly patch may reduce the risk of pregnancy in women who are noncompliant with a daily oral contraceptive regimen, the FDA advises that the potential risks of increased estrogen exposure (eg, thrombotic adverse events) be considered prior to use of the product.

Good advice about risks/benefits analysis, but I am not sure the main point was conveyed. The consideration is between the possible risk (of increased estrogen exposure) with patch use vs. the risk in pregnancy [far riskier, in terms of estrogen levels exposure], not between risk with patch use vs. risk without patch use in a nonpregnant state [lowest risk].

One more interesting finding. I found this message on topic, posted by, I assume, an Ob/Gyn:

By putting a warning label on it, the company is passing the liability on to you. Right now the largest group of law suits are medication problems. If you inform the patient that there may be some risk, have screened for a first degree relative with VTE, and give her the option to switch, and she decides to stay on it anyway, you have met your legal obligation and chances of a sucessful suit is extremely low. (Just attended a meeting on medical legal aspects of hormonal contraception.)

This aspect is something I hadn't considered.