New AIDS Drug Gets FDA Approval
Lexiva: Improved Version of Older Drug
Oct. 21, 2003 -- Lexiva is the newest AIDS drug to get FDA approval.
Lexiva (generic name, fosamprenavir) inhibits HIV, the AIDS virus. It's a member of the protease inhibitor class of anti-HIV drugs.
Lexiva is a new form of an older drug called Agenerase (generic name, amprenavir). Agenerase wasn't particularly popular mainly because it meant taking eight large pills twice a day.
The new version comes in a two-pill-a-day form. To get the full effect, each 700 mg Lexiva tablet may be taken with a 100 mg Norvir (generic name, ritonavir) capsule. However, patients seeking to reduce side effects can take Lexiva twice a day without Norvir.
This offers three dosing options, all without food or water restrictions:
- Two Lexiva tablets plus two Norvir capsules once a day
- One Lexiva tablet plus one Norvir capsule twice a day, or
- Two Lexiva tablets twice a day
Aside from the Norvir -- which lets Lexiva stay in the body longer -- Lexiva is meant to be part of a multidrug anti-HIV regimen. In clinical trials, the drug was given in combination with two other HIV drugs, Ziagen and Epivir.
Lexiva's side effects include diarrhea, nausea, vomiting, headache, and rash. However, these side effects were mild in most patients. Clinical trials showed moderate or severe side effects in fewer than 10% of people who had never received HIV treatment and in fewer than 13% of people who had previously been treated with another protease inhibitor.
Lexiva interferes with one of the body's main mechanisms for eliminating drugs from the body. Serious or life-threatening drug interactions may occur if Lexiva is taken with some other drugs. Patients taking Lexiva must check with their doctor before taking any other medications.
Lexiva should be taken twice daily in patients who have previously used other protease inhibitor drugs to fight HIV.
When It Will Be Available
Lexiva is expected to be distributed to pharmacies in November 2003. Originally discovered by Vertex Pharmaceuticals, the drug is co-developed and distributed by GlaxoSmithKline. GlaxoSmithKline is a WebMD sponsor.
Basis of Approval
Lexiva's approval is based on three clinical trials that enrolled more than 1,200 people. The drug showed durable anti-HIV effects in patients who had and patients who had not been previously treated for HIV.