Saquinavir Mesylate

Indications

Saquinavir is an HIV-1 protease inhibitor indicated for the treatment of HIV1 infection in combination with ritonavir and other antiretroviral agents in adults (over the age of 16 years)

Pharmacology

Saquinavir is a protease inhibitor with activity against Human Immunodeficiency Virus Type 1 (HIV-1). Protease inhibitors block the part of HIV called protease. HIV-1 protease is an enzyme required for the proteolytic cleavage of the viral polyprotein precursors into the individual functional proteins found in infectious HIV-1. Saquinavir binds to the protease active site and inhibits the activity of the enzyme. This inhibition prevents cleavage of the viral polyproteins resulting in the formation of immature non-infectious viral particles. Protease inhibitors are almost always used in combination with at least two other anti-HIV drugs. 

Saquinavir inhibits the HIV viral proteinase enzyme which prevents cleavage of the gag-pol polyprotein, resulting in noninfectious, immature viral particles.

Dosage & Administration

Saquinavir must be administered in combination with ritonavir.

Adults (over the age of 16 years): Saquinavir 1000 mg twice daily (5x200 mg capsules or 2x500 mg tablets) in combination with ritonavir 100 mg twice daily.

Saquinavir and ritonavir should be taken within 2 hours after a meal.

Interaction

Saquinavir/ritonavir is a potent inhibitor of CYP3A, significantly increasing the exposure of drugs primarily metabolized by CYP3A.

Coadministration of Saquinavir/ritonavir with drugs that induce CYP3A may result in decreased plasma concentrations of saquinavir and reduced efficacy.

Certain drugs or drug classes should not be coadministered with Saquinavir/ritonavir based on drug interaction studies or predicted drug interactions

Contraindications

Patients with congenital or documented acquired QT prolongation, patients with refractory hypokalemia or hypomagnesemia, or those on concomitant therapy with other drugs that prolong the QT interval.

Saquinavir is contraindicated in patients with complete atrioventricular (AV) block without implanted pacemakers, or patients who are at high risk of complete AV block.

Saquinavir is contraindicated in patients with clinically significant hypersensitivity (e.g., anaphylactic reaction, Stevens-Johnson syndrome) to saquinavir, saquinavir mesylate, or any of its ingredients

Saquinavir when administered with ritonavir is contraindicated in patients with severe hepatic impairment.

Coadministration of Saquinavir/ritonavir with CYP3A substrates for which increased plasma levels may result in serious or life-threatening reactions.

Coadministration of Saquinavir/ritonavir with rifampin due to the risk of severe hepatotoxicity.

Side Effects

The most common adverse reactions are nausea, vomiting, diarrhea, fatigue, pneumonia, lipodystrophy and abdominal pain

Pregnancy & Lactation

Pregnancy: Use during pregnancy only if the potential benefit justifies the potential risk to the fetus.

Nursing Mothers: Do not breastfeed if HIV-1-infected mothers are receiving Saquinavir therapy.

Use in Special Populations

Pediatric Use: Pediatric dose recommendations that are both reliably effective and below thresholds of concern with respect to QT and PR prolongation could not be determined

Geriatric Use: Caution should be exercised due to greater frequency of decreased hepatic, renal or cardiac function in elderly population.

Impaired Renal Function: No initial dose adjustment is necessary for patients with renal impairment.

Impaired Hepatic Function: No dose adjustment is necessary for patients with mild or moderate hepatic impairment.

Therapeutic Class

Anti-viral drugs

Storage Conditions

The capsules and tablets should be stored at 25 degree C

Available Brand Names

No brand names available