HIV/AIDS Update - New label information affecting all approved protease inhibitors for treatment of HIV

HIV/AIDS Update - New label information affecting all approved protease inhibitors for treatment of HIV
The approved protease inhibitors for the treatment of HIV-1 infection now all include the following drug-drug interaction information:

• Revatio (sildenafil) as a contraindicated medication when prescribed for the treatment of pulmonary arterial hypertension
• Uroxatral (alfuzosin) as a contraindicated medication
• Recommendation that salmeterol (brand names are Advair and Serevent) should not be coadministered
• New dosing recommendation for Tracleer (bosentan) and Adcirca (tadalafil) when prescribed for the treatment of pulmonary arterial hypertension. Note, coadministration of bosentan and Reyataz (atazanavir) without ritonavir is not recommended.
• New dosing recommendations for colchicine when prescribed for the treatment of familial Mediterranean fever or gout
• New dosing recommendations for colchicine when prescribed for the prophylaxis of gout
• Recommendation that colchicine should not be coadministered with protease inhibitors in patients with hepatic or renal impairment

Below is an example of the new dosing recommendations for protease inhibitors and the following concomitant medications:

Colchicine:

Treatment of gout flares: 0.6 mg (1 tablet) x 1 dose, followed by 0.3 mg (half tablet) 1 hour later. Dose to be repeated no earlier than 3 days.

Note: Lexiva (fosamprenavir) without ritonavir: 1.2 mg (2 tablets) x 1 dose. Dose to be repeated no earlier than 3 days.

Prophylaxis of gout-flares: If the original colchicine regimen was 0.6 mg twice a day, the regimen should be adjusted to 0.3 mg once a day. If the original colchicine regimen was 0.6 mg once a day, the regimen should be adjusted to 0.3 mg once every other day.

Note: Lexiva without ritonavir: if the original regimen was 0.6 mg twice a day, the regimen should be adjusted to 0.3 mg twice a day or 0.6 mg once a day. If the original regimen was 0.6 mg once a day, the regimen should be adjusted to 0.3 mg once a day

Treatment of familial Mediterranean fever (FMF): Maximum daily dose of 0.6 mg (may be given as 0.3 mg twice a day)

Note: Lexiva without ritonavir: maximum daily dose of 1.2 mg (may be given as 0.6 mg twice a day)

Bosentan: Treatment of pulmonary arterial hypertension

Coadministration of bosentan in patients already on a protease inhibitor for at least 10 days: Start at 62.5 mg once daily or every other day based upon individual tolerability

Coadministration of protease inhibitor in patients already on bosentan: Discontinue use of bosentan at least 36 hours prior to initiation of protease inhibitor. After at least 10 days following the initiation of the protease inhibitor, resume bosentan at 62.5 mg once daily or every other day based upon individual tolerability

Note: Coadministration of bosentan in patients on Crixivan (indinavir) or Viracept (nelfinavir) or coadministration of indinavir or nelfinavir in patients on bosentan. Start at or adjust bosentan to 62.5 mg once daily or every other day based upon individual tolerability.

Tadalafil (Adcirca): Treatment of pulmonary arterial hypertension

Coadministration of Adcirca in patients already on a protease inhibitor for at least one week: Start tadalafil at 20 mg once daily. Increase to 40 mg once daily based upon individual tolerability.

Coadministration of protease inhibitor in patients already on tadalafil:
Avoid use of tadalafil during initiation of protease inhibitor. Stop tadalafil at least 24 hours prior to starting protease inhibitor. After at least one week following initiation of protease inhibitor, resume tadalafil at 20 mg once daily. Increase to 40 mg once daily based upon individual tolerability.

Note: Coadministration of Adcirca in patients already on nelfinavir or indinavir or coadministration of nelfinavir or indinavir in patients already on Adcirca: Start at or adjust Adcirca to 20 mg daily. Increase to 40 mg once daily based upon individual tolerability.

Richard Klein
Office of Special Health Issues
Food and Drug Administration
Kimberly Struble
Division of Antiviral Drug Products
Food and Drug Administration