Intelence: New HIV drug is smart choice for some

TIPS TO REMEMBER Intelence

HIV and AIDS patients harboring drug-resistant virus may find that a newly approved antiretroviral offers some hope when little else does. The non-nucleoside reverse transcriptase inhibitor, etravirine (Intelence) from Tibotec Pharmaceuticals, is the first NNRTI to be granted regulatory approval in almost a decade and, according to the manufacturer, is the first to show activity against virus strains that are already resistant to other drugs in the same class.

Study results showed 59.8% patients in the etravirine arm achieved undetectable viral load (<50 copies/ml) while only 40.2% met the goal in the BR arm. A significantly greater mean increase in CD4+ cell count was also seen in the etravirine group, 81 versus 64 cells/mm3. DUET-1 and DUET-2 study results were published in two separate articles in the July 7, 2007, issue of The Lancet. Just recently, Tibotec released 48-week data that also showed significant differences in etravirine-treated patients compared with BR only. Undetectable viral load was achieved in 60% and 61% in patients on etravirine compared with 39% and 41% on BR in DUET-1 and DUET-2, respectively. CD4+ cell counts also increased significantly in patients on etravirine compared with BR after 48 weeks of treatment.

The most common adverse events, occurring in >10% of patients, were rash and nausea. According to Tibotec, the rash is typically mild to moderate, occurred in the second week of treatment, and generally resolved within a few weeks of therapy. Adverse events that occurred in 2% or more patients included diarrhea, abdominal pain, nausea, vomiting, peripheral neuropathy, fatigue, headache, and hypertension. Stevens-Johnson Syndrome, hypersensitivity reactions, erythema multiforme, and immune reconstitution syndrome were reported, but their incidence was rare.

According to the prescribing information, etravirine should not be taken with ritonavir (Norvir, Abbott) in combination with tipranavir (Aptivus, Boehringer Ingelheim), fosamprenavir (Lexiva, GSK), or atazanavir (Reyataz, Bristol-Myers Squibb); PIs administered without ritonavir; or other NNRTIs. Co-administration of etravirine with CYP3A4, CYP2C9, and/or CYP2C19 inducers or inhibitors may alter the efficacy or adverse-reaction profile of etravirine, and substrates of the same enzymes may also be affected when co-administered with etravirine.

Tibotec Pharmaceuticals has placed the introductory wholesale pricing for etravirine at $21.80 per day, or close to $8,000 per patient, per year. Prescribing information can be accessed at http://www.intelence-info.com/.