Brand name: Viracept
Generic name: nelfinavir, or NFV
Class: Protease inhibitor (PI)
Manufacturer: ViiV Healthcare, www.viivhealthcare.com, (877) 844-8872
AWP: $919.44/month for 250 and 625 mg tablets
Standard Dose: 1,250 mg taken as either two 625 mg tablets or five 250 mg tablets twice daily with food. Take missed dose as soon as possible, unless it is closer in time to your next dose. Do not double up on your next dose. Viracept oral powder also available for children two years or older and individuals unable to swallow tablets.
Potential side effects and toxicity: Most common include diarrhea, stomach discomfort, nausea, gas, weakness, and rash. People with phenylketonuria should be aware that the powder contains phenylalanine. See chart for potential drug class side effects.
Potential drug interactions: PIs interact with many other drugs. See package insert for the most complete list. Tell your provider or pharmacist about all medications, herbs, and supplements you are taking or thinking of taking, prescribed or not. Viracept increases levels of Invirase and Crixivan, so dose adjustments may be needed. Do not take with alfuzosin, Revatio, oral Versed (midazolam), Cordarone (amiodarone), Halcion (triazolam), Rifadin (rifampin), Prilosec OTC (omeprazole), garlic supplements, or the herb St. John's wort. Do not use Advicor, Altoprev, Livalo, Mevacor (lovastatin), Simcor, Vytorin, or Zocor (simvastatin) for the treatment of high cholesterol. Cholesterol-lowering alternatives are Crestor, Lescol, Lipitor, and Pravacol (pravastatin), but should be used with caution and started at the lowest dose possible; monitor closely for increased side effects from these medications. Viracept may decrease methadone levels and methadone may need to be increased, but withdrawal rarely occurs. Use calcium channel blockers with caution. Blood levels of Viracept are reduced by rifampin and may be reduced by phenobarbital, phenytoin, and carbamazepine (Tegretol and others), so it is important to inform your doctor if you are taking any of these medications. Mycobutin (rifabutin) dose must be decreased when used with Viracept. Prescriber may need to adjust doses of any of these drugs accordingly. Cialis, Levitra, and Viagra levels are increased; doses should not exceed 10 mg Cialis or 2.5 mg Levitra per 72 hours, or 25 mg Viagra per 48 hours. Increases levels of fluticasone (found in Advair, Flonase, and Flovent); use only if the benefits outweigh the risks, and monitor for signs of Cushing's syndrome (increased fat in the abdomen, fatty hump between the shoulders, rounded face, red/purple stretch marks on the skin, bone loss, possible high blood pressure, and sometimes diabetes). Effectiveness of birth control pills may be decreased; consider the use of alternative or additional methods of contraception. Also, increased levels of trazodone can occur and this combination should be used with caution. A lower dose of trazodone is recommended. Use with caution with bosentan, salmeterol, immunosuppressants (including transplant drugs), and colchicine (lower colchicine dose).
More information: Rarely used, Viracept is the only protease inhibitor that is never used with Norvir. Do not leave the pharmacy without anti-diarrhea meds such as Immodium, or Tums or other calcium products. Taking a 500 mg calcium supplement with doses hugely decreases diarrhea. Also try Solgar oat bran tablets, psyllium husk fiber bars, and pancreatic enzymes (all with meals). As an extra precaution, take a change of clothes with you every day for the first several weeks -- stick it out, most often, symptoms improve after two or three weeks. The oral powder tastes horrible and requires a large amount for mixing into food. People using Viracept can crush adult tablets or dissolve tablets in a small amount of water. Mixing Viracept with acidic food or juice (e.g., orange/apple juice or apple sauce) is not recommended, due to resulting bitter taste. To get the full benefit of Viracept by increasing its level in the body, it must be taken with a meal. No longer a preferred PI in pregnancy, Viracept is still okay to use if the preferred and alternative PIs (Kaletra and Reyataz) are not an option. It has been used extensively in pregnancy in the past, and it is well tolerated during pregnancy. In 2007, Viracept manufactured in Europe was recalled from the market because of high levels of ethyl methane mesylate (EMS). Viracept manufactured in United States was found to have lower levels of EMS than the European product. However, the FDA recommended that pregnant women not be treated with Viracept and that pediatric patients not be started on Viracept. By early 2008, Viracept manufactured both in Europe and the U.S. was found to meet safety standards, and the FDA and European Medicines Agency lifted their warnings about safety. See package insert for more complete information on potential side effects and interactions.
Viracept was once a popular alternative to more toxic or inconvenient PIs like Crixivan or Invirase/Norvir. However, there was a price to be paid for the greater convenience and relative tolerability (I say "relative" because it caused a lot of diarrhea). It was less effective than other PIs, a fact that became clear in a head-to-head comparison with Kaletra. This may have been due in part to variable absorption and drug levels. And while its initial claim to fame was that Viracept mutations didn't cause resistance to other PIs, that wasn't always the case, and people on Kaletra didn't develop mutations anyway. Viracept, the only "unboostable" PI, gradually fell out of favor, and is no longer recommended or widely used.
-- Joel Gallant, M.D., M.P.H.
One of the very first protease inhibitors, it has pretty much disappeared into the history books. Main side effects were diarrhea, and its only use I can think of now is for women trying to conceive, as it is one of the alternative drugs for prevention of mother-to-child transmission, especially in developing countries. I haven't seen a person on it, or dealt with it in years.
-- Joey Wynn