Delavirdine (Rescriptor)

Summary

Delavirdine is a type of anti-HIV drug called a non-nucleoside reverse transcriptase inhibitor. The most common side effect is a skin rash that usually goes away on its own. Delavirdine is taken three times a day, with or without food.

What is delavirdine?

Delavirdine, sold under the brand name Rescriptor, is a type of antiretroviral drug called a non-nucleoside reverse transcriptase inhibitor.

How does delavirdine work?

To explain how delavirdine works, we need to first tell you some information about HIV. When HIV infects a cell, it takes control of that cell. HIV then forces the cell to make many more copies of the virus. To make these copies, the cell uses proteins called enzymes. When the activity of these enzymes is reduced the production of HIV slows.

Delavirdine belongs to a group of drugs called non-nucleoside reverse transcriptase inhibitors (NNRTIs or “non-nukes”). The enzyme reverse transcriptase is used by HIV-infected cells to make new viruses. Since delavirdine inhibits, or reduces the activity of this enzyme, this drug causes HIV-infected cells to produce fewer viruses.

How do people with HIV use delavirdine?

Delavirdine is rarely used in Canada today.

Delavirdine  is used in combination with other anti-HIV drugs. For more information on combinations of anti-HIV drugs, see CATIE’s Your Guide to HIV Treatment.

For many people with HIV, the use of anti-HIV drugs has increased their CD4 count and decreased the amount of HIV in their blood (viral load). These beneficial effects help to reduce the risk of developing life-threatening infections. Neither delavirdine nor any other anti-HIV medication is a cure for HIV. It is therefore important that you do the following:

  • See your doctor regularly so that he or she can monitor your health.
  • Continue to practise safer sex and take other precautions to avoid passing HIV on to other people and protect yourself from different strains of HIV as well as other germs.

Resistance and cross-resistance

Over time, as HIV makes copies of itself, the virus can change its structure. These changes allow HIV to resist the effects of antiretroviral drugs. Resistance to non-nukes, when used alone, appears as early as two weeks after treatment begins. Combining delavirdine with at least two other drugs may delay the development of drug resistance. To limit the risk of resistance, all antiretroviral drugs should be taken every day, exactly as prescribed. This strict schedule is necessary because resistant virus can develop if the level of drug in the blood drops. This may happen if doses are delayed or skipped.

It’s generally believed that all non-nukes may be cross-resistant. This means that, if HIV becomes resistant to one non-nuke, it may also be able to resist the effects of the other non-nukes. In other words, if the virus has become resistant to delavirdine it will probably be resistant to nevirapine and efavirenz.

Side effects

The most common side effect of delavirdine is a skin rash. The rash appears as red, slightly raised patches on the skin and may be itchy. Rash usually develops within the first three weeks of taking delavirdine. Although it often disappears on its own after a couple of weeks, anyone who develops a rash while using delavirdine should consult their doctor as soon as possible. If the rash is accompanied by fever, skin blisters, itching or burning eyes, swelling, muscle or joint pain, delavirdine must be stopped.

Other side effects include headache, nausea, diarrhea, fatigue, fever, and changes in dreams.

Blood tests may show higher than usual levels of liver enzymes.

To date, there have been no reports of side effects unique to women.

Drug interactions

As delavirdine has complex interactions with other drugs, always consult a pharmacist and doctor who is experienced with prescribing or dispensing this drug. Dosages of other drugs may have to be raised or lowered, or some drugs may have to be changed.

Drugs that should not be taken with delavirdine include terfenadine (Seldane) and astemizole (Hismanal), phenytoin, phenobarbital, carbamazepine (Tegretol), triazolam (Halcion), alprazolam (Xanax), midazolam (Versed), rifampin, rifabutin (Mycobutin), cimetidine (Tagamet), ranitidine (Zantac), nizatidine (Axid), famotidine (Pepcid), quinidine, dapsone, and cisapride (Prepulsid). If you’re starting a new drug, check with your doctor or pharmacist about potential interactions with delavirdine.

Delavirdine should be taken at least one hour before or one hour after taking ddI or any antacid (Maalox, Rolaids, Tums, etc.).

Dosage

The recommended dose of delavirdine is 400 mg taken three times daily, with or without food.

Availability

Delavirdine is licensed in Canada for the treatment of HIV infection in adults. Your doctor can tell you more about the availability and coverage of delavirdine in your region. CATIE’s online module Federal, Provincial and Territorial Drug Access Programs also contains information about Canadian drug coverage.

Reference

ViiV Healthcare. Rescriptor. Product monograph. 5th March, 2013.

Author(s): Maclean D, Toulouse B

Published: 2014