Genvoya-Associated and Simvastatin-Associated Noninflammatory and Nonautoimmune Myopathy: A Case Report and Literature Review.

ABSTRACT
Patients with HIV have a higher incidence of rhabdomyolysis compared with the HIV negative population because of medication-related myotoxicity and drug-drug interactions. Statins and antiretroviral therapy have been previously reported to cause myopathy in patients with HIV when used alone or in combination. In this study, we describe a case of biopsy-proven noninflammatory and nonautoimmune myopathy associated with the use of simvastatin and Genvoya (elvitegravir/cobicistat/emtricitabine/tenofovir alafenamide fumarate) and review 3 previously reported similar cases. Our patient presented with acute proximal limb weakness and significantly elevated serum creatine kinase. Muscle biopsy revealed scattered degenerating and regenerating muscle fibers without evidence for an inflammatory process. She did not respond to empiric treatment with high-dose intravenous steroids and intravenous immunoglobulin. Her creatine kinase only began to downtrend after discontinuation of both simvastatin and Genvoya, and she returned to baseline function at 2-month follow-up. Our case highlights the importance of recognizing drug-drug interactions between HIV and statin medications in causing significant noninflammatory myopathy. In these patients, both categories of medications need to be discontinued for recovery.