Incivek, a drug used to treat Hepatitis C, can cause a potentially fatal skin reaction known as Stevens Johnson Syndrome when taken in combination with other medications. In fact, the U.S. Food and Drug Administration (FDA) has added its most serious warning label to Incivek because of this risk.

Incivek is manufactured by Vertex Pharmaceuticals and although skin rashes are already a documented side effect of this drug, new data showed that the reaction was much more severe, even deadly, in some patients.

What is Stevens Johnson Syndrome?

Stevens Johnson Syndrome (SJS)
, also known as Erythema Multiforme, Leyll’s Syndrome, and in its later stages, Toxic Epidermal Necrolysis (TEN), is a serious and potentially life-threatening disease that causes large areas of the skin to become detached and lesions to develop in the mucous membranes.

Stevens Johnson Syndrome Symptoms

Stevens Johnson Syndrome (SJS) is a rare but serious skin reaction that occurs as a result of a medication or infection. It often starts off with flu-like symptoms and then progresses to a rash that spreads and blisters. Eventually, the top layer of the skin dies and sheds if not treated. SJS is considered a medical emergency and requires immediate hospitalization. According to the Mayo Clinic, the signs of SJS include:

• Flu-like symptoms, such as fever, sore throat, cough, burning eyes
• Facial swelling
• Tongue swelling
• Hives
• Skin pain
• A red or purple skin rash that spreads within hours to days
• Blisters on your skin and the mucous membranes of your mouth, nose, eyes and genitals
• Skin shedding or sloughing

Before the onset of the rash, patients with SJS may experience flu-like symptoms such as:

• Fever
• Sore throat
• Cough
• Burning eyes

FDA Warns About Risk of Stevens Johnson Syndrome When Taking Incivek

On December 19, 2012, the U.S. Food and Drug Administration (FDA) issued a Drug Safety Communication stating that it had received some reports of serious, sometimes fatal, skin reaction among patients taking Incivek in combination with peginterferon alfa and ribavirin (an Incivek combination treatment). The agency said that some patients died when they kept taking the Incivek combination treatment after developing a worsening rash and systemic symptoms (symptoms that affect the whole body).

The FDA added a black box warning to the Incivek drug label stating that combination treatment should be stopped immediately if the patient experiences a rash with systemic symptoms or a worsening severe rash. Black box warnings are the most serious types of warning labels available.

Allergic drug reactions cause more than 100,000 deaths among patients in the United States each year, and adverse drug reactions are the leading causes of death in the U.S. Every day, more than 4,000 patients—approximately 1.5 million per year—are admitted to hospitals with serious adverse drug reactions. Many of these admissions can be prevented.