Saquinavir and ritonavir HIV drug combination may lead to serious heart problems, warns US FDA

Combined use of anti-HIV drugs saquinavir and ritonavir may lead to serious heart problems, US FDA alerted in its latest safety report.

Saquinavir and ritonavir are marketed as Invirase and Norvir brand names by San Francisco-based Genentech, a subsidiary of the Roche Group and Abbott Park, Ill.-based Abbott Laboratories respectively.

Invirase (saquinavir) is an antiretroviral medication that was first approved in 1995.

Invirase is used in combination with Norvir and other antiretroviral medicines to treat HIV in adults. Invirase does not cure HIV infection, may not prevent anybody from developing HIV-related illnesses, and may not prevent you from spreading HIV to other people.

Saquinavir and ritonavir in India

Saquinavir generics are available in India in several brand names such as Saquin by Hetero Drugs and Maximune by Cipla Ltd.

Ritonavir is marketed in India under various brand names including Ritomune (Cipla Ltd), Viriton (Ranbaxy), Rotovir (Hetero drugs), Empetus (Emcure Pharma) and Ritomax (Alkem Labs).

Preliminary clinical data suggests that Invirase (saquinavir) in combination with Norvir (ritonavir) may have potentially important adverse effects on the heart, the U.S. Food and Drug Administration announced.

When used together, the drugs may cause prolongation of the QT and PR intervals on an electrocardiogram.

The PR interval estimates of function of the heart and a prolonged QT interval is a risk factor for ventricular tachyarrhythmias and sudden death.

Prolongation of the QT interval may lead to a condition known as torsades de pointes, an abnormal heart rhythm. Prolongation of the PR interval may also lead to an abnormal heart rhythm known as heart block.

With torsades de pointes or with heart block, patients may experience lightheadedness, fainting, or abnormal heart beats. In some cases, torsades de pointes may progress to a life-threatening irregular heart beat known as ventricular fibrillation.

Review of the data is ongoing, US FDA said.

Preliminary findings suggest that some patients using Invirase (saquinavir) and Norvir (ritonavir) may be at an increased risk for heart abnormalities leading to irregular heart rhythms.

For example, the risk for torsades de pointes may be increased in patients who are also using medications known to cause a heart disturbance called QT interval prolongation. The risk may also be increased in patients who have a history of QT interval prolongation.

Patients using Invirase (saquinavir) should talk to their health care professional about any questions or concerns they have about Invirase. Patients and health care professionals should report any side effects from the use of Invirase to the FDA’s MedWatch program:
http://www.fda.gov/safety/MedWatch/default.htm1, FDA alerted.

HIV is a worldwide disease with different subtypes (or clades) of the virus predominating in different regions of the world.  Clade B is the predominant subtype in North America.  Globally, most infections involve subtypes AG, B, and C.

33 million people are currently infected globally and it is estimated that there will be 2.5 million new infections this year.

Since the beginning of the epidemic, over a million people in the U.S. have contracted the virus.  Every 9 1/2 minutes, someone in the U.S. is infected with AIDS.

Globally, HIV is the top killer among women of reproductive age.

In 2008, antiretroviral treatment in low and middle income countries was restricted to about 3 million people.

In the United States, about 50% of those who are infected are estimated to be on drug treatment.

HIV infects 60,000 new new people annually in the United States alone. Antiretroviral drugs, which have to be taken for life, have side effects and are expensive, costing on average $18,000 per year.