Brand name: Agenerase

Common name: amprenavir

Class: HIV protease inhibitor (PI)

Standard dose: 1200 mg twice daily. The 150 mg soft gelatin capsules were taken off the market last year because of the new formulation (Lexiva), but the 50 mg capsule remains available. Take missed dose as soon as possible, but do not double up on your next dose.
Approved for children ages 4 and older. Grape, bubblegum, peppermint flavored liquid available. Adults should not use liquid if possible.

AWP: $257.19 / month for 50 mg, 480 capsules

Manufacturer contact: GlaxoSmithKline, www.treathiv.com, 1 (800) 722–9294

AIDS Treatment Information Service: 1 (800) HIV–0440 (448–0440)

Potential side effects and toxicity: Most common include: nausea, vomiting, stomach pain, taste disorders, fatigue, headache, mood disorders, anemia and rash. Rash occurred in about 22% of people on Agenerase, but severe rashes were uncommon. If you experience a rash, notify your doctor. For mild or moderate rashes, your doctor may choose to continue Agenerase, with close follow-up and monitoring. Because Agenerase is a sulfonamide, it should be used with caution in patients with allergies to sulfa drugs. Severe rash (see Viramune) and stomach problems (pancreatitis—see NRTIs) while rare, can be severe; notify your healthcare provider immediately.

As seen with all other protease inhibitors are increased levels of cholesterol and triglycerides, except possibly unboosted Reyataz (atazanavir) and these increased levels may be associated with heart disease. Other possible side effects are lipodystrophy (body fat changes, including thinning of the face, arms and legs, with or without fat accumulation in the stomach, breasts and sometimes the upper back), onset of new cases or worsening of diabetes (see your doctor promptly) and increased bleeding in hemophiliacs.

Potential drug interactions: Do not take with Tambocor (flecainide), Rythmol (propafenone), Versed, Halcion, Hismanol, Seldane, rifampin, ergot derivatives (such as Cafergot, Wigraine and Methergine, D.H.E. 45, in any form—serious interactions seen with dilation during gynecological exams), garlic supplements, or the herb St. John’s wort. Do not use Zocor (simvastatin) or Mevacor (lovastatin); lipid-lowering alternatives are Lipitor (atorvastatin), Lescol, and Pravachol (pravastatin), but they should be used with caution due to potential for liver toxicity. Do not take extra vitamin E.

Rescriptor and Viracept greatly increase Agenerase blood levels (and usually stomach discomfort) and prescriber may need to adjust dose accordingly. Sustiva has been shown to significantly reduce blood levels of Agenerase unless also taken with Norvir.

Other drugs that may be involved in interactions with Agenerase include drugs for your heart (antiarrhythmics, anticoagulants, blood pressure medications, cholesterol medications), drugs for seizures, antibiotics and antifungals, sedatives, steroids, immunosuppresants, drugs for heartburn or acid reflux, oral contraceptives, and antidepressants. If you are taking any of these drugs, be sure to let your doctor and pharmacist know so they can monitor your therapy or make adjustments to your medications.

Protease inhibitors increase blood levels of Viagra (sidenafil citrate), Cialis (tadalafil) and Levitra (vardenafil). Use with caution. Initially the Viagra dose should be 12.5 mg (1/2 of 25 mg tablet) and increased as needed and tolerated. It’s recommended that people on PIs do not exceed 25 mg of Viagra in a 48-hour period because of potential for serious reaction. Use Cialis at reduced doses of 10 mg every 72 hours and Levitra at reduced doses of no more than 2.5 mg every 72 hours, with increased monitoring for adverse events.

Tips: On its way to extinction due to new formulation on the market, fos-amprenavir calcium (Lexiva). If you are on Agenerase, you should talk with your doctor about switching to Lexiva. Alternative doses: Agenerase 1200 mg with Norvir 200 mg both once daily; or Agenerase 600 mg with Norvir 100 mg both twice daily. However, you should avoid taking Agenerase with food high in fat, while side effects of Norvir are reduced with food high in fat. Go figure.

May also penetrate the lymph nodes, where virus can hide out. Label warning: Agenerase Oral Solution should not be given to infants and children below the age of 4 years and should not be used by pregnant women because of the propylene glycol amount.