Vitekta (elvitegravir) - HIV Drug Information

Drug Prevents HIV from Hijacking a Cell's Genetic Machinery

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Image courtesy Gilead Science

Classification

Vitekta (elvitegravir) is an antiretroviral drug classified as an integrase inhibitor which is used in the treatment of HIV. Integrase inhibitors work by blocking an HIV enzyme called integrase, which HIV uses to integrate its genetic coding into the host cell's DNA. By blocking integrase, the virus is unable to complete its life cycle and create other HIV virions.

Vitekta was approved by the U.S. Food and Drug Administration (FDA) in September 2014 for use in adults previously exposed to HIV therapy.

Elvitegravir is a component of the fixed dose combinations drug Stribild (also popularly known as the "Quad Pill") and the second-generation version of Stribild called Genvoya.

Drug Formulation

Vitekta is available in two tablet formulations:

  • An 85 mg pentagon-shaped, film-coated tablet, green in color with "GSI" embossed on one side and "85" on the other.
  • A 150 mg triangle-shaped, film-coated tablet, green in color with "GSI" embossed on one side and "150" on the other.

Dosage

Vitekta must always be used in combination therapy with both an HIV protease inhibitor (PI) and Norvir (ritonavir), a "boosting" agent which extends the concentration of the accompanying drugs in the blood. Vitekta must be taken with food.

The recommended dosage varies by drug selection as follows:

Vitekta  dosageProtease Inhibitor dosageNorvir (ritonavir) dosage
85mg once dailyReyataz (atazanavir) 300mg once daily100mg once daily
85mg once dailyKaletra (400mg lopinavir + 100 mg ritonavir) twice dailyNot required as ritonavir is already contained in Kaletra formulation
150mg once dailyPrezista (darunavir) 600mg twice daily100mg twice daily
150mg once dailyLexiva (fosamprenavir) 700mg twice daily100mg twice daily
150mg once dailyAptivus (tipranavir) 500mg twice daily200mg twice daily

Common Side Effects

In Phase III human clinical studies, a number of potential drug side effects have been identified in patients taking Vitekta. The most common events, reported in at least 2% of the trial participants include:

  • Diarrhea
  • Nausea
  • Headache

Less common side effects include abdominal pain, indigestion, rash, fatigue and vomiting.Side effects were generally transient, with few patients discontinuing as a result of treatment intolerance.

Drug Contraindications

Vitekta should not be taken with the following drugs or herbal supplements:

  • Hepatitis C medication: Invicek, Victrelis
  • Rifampin-based anti-tuberculosis medications: Rifater, Rifamate, Rimactane, Rifadin, Priftin (substitute with Mycobutin)
  • St. John's Wort

Always inform your doctor of any drug or supplement, prescribed or non-prescribed, that you may be taking before starting any antiretroviral therapy.

Antiretroviral Drug Interactions

The use of Vitekta with following antiretroviral drugs may result either in the loss of therapeutic effect of the accompanying drug or an increase of side effects:

  • Sustiva (efavirenz) should not be coadministered with Vitetkta.
  • Viramune (nevirapine) should not be coadministered with Vitekta.
  • Videx (didanosine) should either be taken one hour before or two hours after a Vitekta dose.
  • Tybost (cobicistat), a boosting agent similar to Norvir, should not be taken with Vitekta when coadministered with a protease inhibitor.

Other Considerations

Antacids can prevent Vitekta from being properly absorbed.

If you are using an over-the counter antacid (e.g. Rolaids, Tums, Milk of Magnesia), it is suggested that it be taken either two hours before or after a dose of Evotaz.

Women should advise their doctor if they are taking or planning to take birth control pills. Vitekta, when used with Norvir, can significantly reduce the plasma concentration of ethinyl estradiol /norgestimate hormonal contraceptives. Alternative methods of non-hormonal contraception are recommended. Never increase hormonal contraceptive dosages. It is advised that nursing mother not breastfeed if they are HIV positive as it potentially transmit the virus to the infant.

Vitekta contains lactose so be sure to advise your doctor if you are lactose intolerant.

Sources:

U.S. Food and Drug Administration (FDA). "VITEKTA - FULL PRESCRIBING INFORMATION." Silver Srpring,Maryland; accessed February 3, 2015.

FDA. "FDA approves new combination pill for HIV treatment for some patients." Silver Spring, Maryland; press release issued on August 27, 2012.

Gilead Sciences. "Genvoya - Highlights of Prescribing Information." Foster City, California; accessed December 14, 2015.

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