Antiviral Drug Allergy

Abstract

Antiviral drugs used to treat HIV and hepatitis C are common causes of delayed drug hypersensitivities for which many of the more severe reactions have been recently shown to be immunogenetically mediated such as abacavir hypersensitivity where HLA-B*57:01 is now used routinely as a screening test to exclude patients carrying this allele from abacavir prescription. Most antiviral drug allergies consist of mild to moderate delayed rash without other serious features (e.g. fever, mucosal involvement, blistering rash, organ impairment. In these cases treatment can be continued with careful observation and symptomatic management and the discontinuation rate is low.

Hypersensitivity to antiretroviral drugs

“…HLA-B*5701 has great utility as a screening test, with 100% negative predictive value generalizable across different ethnicities to identify patients at risk to develop abacavir hypersensitivity (12,13). The complexity of HLA associations across different phenotypes and ethnicities with other drugs like nevirapine is such that currently HLA testing has limited utility as a screening strategy to prevent nevirapine hypersensitivity syndromes before nevirapine prescription (14). MHC HLA class II allele HLA-DRB1*0101 has been associated with nevirapine hypersensitivity (15).…”

“…The most common cutaneous drug reaction in HIV-infected patients are maculopapular exanthemas, often accompanied by pruritus without fever (15). These eruptions usually appear between 2 and 10 weeks after primary exposure to antiretroviral therapy and within 1 to 2 days of rechallenge (14). Cutaneous problems and hepatoxicity are the main side effects induced by NNRTIs (14).…”

“…These eruptions usually appear between 2 and 10 weeks after primary exposure to antiretroviral therapy and within 1 to 2 days of rechallenge (14). Cutaneous problems and hepatoxicity are the main side effects induced by NNRTIs (14). All NNRTIs have been associated HR to emtricitabine and tenofovir was considered probable based on positive PT in the patient and negative PT in 7 controls (table II).…”

Photodermatitis in a woman on antiretroviral therapy: report of a rare cutaneous adverse drug reaction of efavirenz and review of literature

“…Multiple drugs prescribed for HIV infection or to prevent associated infections predispose these patients for a multitude of adverse drug reactions varying from mild exanthematous rash to life threatening Stevens Johnson syndrome (SJS), toxic epidermal necrolysis occurring in 2–10% cases . Non‐nucleotide reverse transcriptase inhibitors (NNRTIs), nevirapine, etravirine, delavirdine, and efavirenz are frequent offending drugs in 10–17% of cases receiving them while efavirenz alone accounts for 0.1% of severe reactions .…”

Report from the National Institute of Allergy and Infectious Diseases workshop on drug allergy

“…(7) How much of the increase in risk in CF and HIV is due to higher exposure and how much to disease-related factors is unclear. (8)…”