Ziagen Warnings

Hypersensitivity (see Adverse Reactions): Abacavir is associated with a risk for hypersensitivity reactions (HSR) characterized by fever and/or rash with other symptoms indicating multi-organ involvement. HSR can be life-threatening, and in rare cases fatal, when not managed appropriately. The risk for abacavir HSR to occur is significantly increased for patients who test positive for the HLA-B*5701 allele. However, abacavir HSRs have been reported at a lower frequency in patients who do not carry this allele.
The following should be adhered to: Testing for HLA-B*5701 status should be considered before initiating abacavir treatment and also before re-starting abacavir treatment in patients of unknown HLA-B*5701 status who have previously tolerated abacavir.
ZIAGEN is not recommended for use in patients with the HLA-B*5701 allele, or in patients who have had a suspected abacavir HSR while taking any other medicinal product containing abacavir (e.g. KIVEXA,) regardless of HLA-B*5701 status.
Each patient should be reminded to read the Patient Leaflet included in the ZIAGEN pack. They should be reminded of the importance of removing the Alert Card included in the pack, and keeping it with them at all times.
In any patient treated with ZIAGEN, the clinical diagnosis of suspected hypersensitivity reaction must remain the basis of clinical decision making.
ZIAGEN must be stopped without delay, even in the absence of the HLA-B*5701 allele, if a HSR is suspected. Delay in stopping treatment with ZIAGEN after the onset of hypersensitivity may result in a life-threatening reaction.
Patients who have experienced a hypersensitivity reaction should be instructed to dispose of their remaining ZIAGEN tablets in order to avoid restarting abacavir.
Restarting abacavir containing products following a suspected abacavir HSR can result in a prompt return of symptoms within hours, and may include life-threatening hypotension and death.
Regardless of a patient's HLA-B*5701 status, if therapy with any abacavir containing product has been discontinued for any reason and restarting abacavir therapy is under consideration, the reason for discontinuation must be established. If HSR cannot be ruled out, ZIAGEN or any other medicinal product containing abacavir (e.g. KIVEXA) must not be restarted.
If a hypersensitivity reaction is ruled out, patients may restart ZIAGEN. Rarely, patients who have stopped abacavir for reasons other than symptoms of HSR have also experienced life-threatening reactions within hours of re-initiating abacavir therapy (see Description of selected adverse reactions under Adverse Reactions). Patients must be made aware that HSR can occur with reintroduction of ZIAGEN or any other medicinal product containing abacavir (e.g. KIVEXA) and that reintroduction of ZIAGEN or any other medicinal product containing abacavir (e.g. KIVEXA) should be undertaken only if medical care can be readily accessed.
Clinical Description of abacavir HSR: Abacavir HSR has been well characterised through clinical studies and during post marketing follow-up. Symptoms usually appeared within the first six weeks (median time to onset 11 days) of initiation of treatment with abacavir, although these reactions may occur at any time during therapy.
Almost all HSR to abacavir include fever and/or rash as part of the syndrome.
Other signs and symptoms that have been observed as part of abacavir HSR include respiratory and gastrointestinal symptoms, which may lead to misdiagnosis of HSR as respiratory disease (pneumonia, bronchitis, pharyngitis), or gastroenteritis (see Description of Selected Adverse Reactions under Adverse Reactions). The symptoms related to HSR worsen with continued therapy and can be life threatening. These symptoms usually resolve upon discontinuation of ZIAGEN.