Efavirenz severe hypersensitivity reaction: case report and rapid desensitization protocol development

Area of Science:

• Infectious Diseases
• Pharmacology
• Immunology

Background:

• Efavirenz is a key component in many antiretroviral therapy (ART) regimens for HIV.
• Hypersensitivity reactions (HSRs) to efavirenz, often presenting as cutaneous reactions, can complicate ART.
• While long-term desensitization protocols exist, rapid desensitization protocols for efavirenz HSRs have not been widely reported.

Observation:

• A 52-year-old HIV-positive woman developed a severe, generalized rash after initiating ART including efavirenz.
• Initial attempts to manage the rash by discontinuing and re-challenging efavirenz were unsuccessful, leading to severe symptoms.
• The patient experienced a severe pruritic rash upon re-challenge with efavirenz, necessitating complete discontinuation of ART.

Findings:

• A rapid desensitization protocol, involving a graded dose escalation to the target therapeutic dose, was successfully implemented.
• The patient tolerated the rapid desensitization protocol without further signs or symptoms of hypersensitivity.
• Follow-up for six weeks confirmed the sustained resolution of the hypersensitivity reaction.

Implications:

• This case demonstrates the feasibility and success of a rapid desensitization protocol for managing severe efavirenz-induced hypersensitivity.
• Rapid desensitization provides a potentially crucial option for patients experiencing efavirenz HSRs, preserving treatment choices.
• Such protocols are particularly valuable in resource-limited settings where access to alternative antiretroviral drugs may be restricted.