WASHINGTON — The FDA alerted healthcare professionals that the HIV medication etravirine (Intelence) may cause severe skin reactions and the manufacturer has updated the drug’s label accordingly.

The new language comes after postmarketing reports of a death from toxic skin necrolysis and cases of hypersensitivity reactions, some of which involved hepatic failure.

Patients are warned to discontinue the drug immediately if severe rash develops.

The new reports contradict a pooled analysis presented last November, comparing data from the DUET-1 and DUET-2 trials, that found that the non-nucleoside reverse transcriptase inhibitor did not cause hepatic toxicity. (See AASLD: Etravirine Safe for Liver After at Least a Year)

Phase III studies of the drug showed the most common adverse effect was a grade 2 or greater rash, which occurred in 9% of patients. Only 2% discontinued use because of the rash. Grade 3 and 4 rashes were reported in 1.3% of participants.

Stevens-Johnson syndrome, hypersensitivity, and erythema multiforme were also reported in less than 0.1% of patients, the manufacturer said.

When the drug was approved to treat refractory HIV in January 2008, the FDA reported that it did not know the long-term effects of etravirine; nor did it know the effectiveness of the drug in adolescents 16 and younger or in pregnant woman. (See Etravirine Approved to Treat Drug-Resistant HIV)

“Overall, the cases referenced above within clinical and postmarketing experience illustrate the importance of clinical vigilance and familiarity with the signs and symptoms of severe skin rash and hypersensitivity reactions,” said Ron Falcon, MD, vice president of Clinical Affairs at Tibotec Therapeutics, in a prepared statement.

Related Article(s):

• AASLD: Etravirine Found Still Safe for Liver After at Least a Year
• Etravirine Approved to Treat Drug-Resistant HIV