Date of report 16 Apr 2024

Reported case interaction between
Rilpivirine and RIFAMPIN

A 49-year-old Sudanese male presented with several weeks of progressive encephalopathy and was found in septic shock with multi-organ failure, including respiratory failure requiring mechanical ventilation and acute renal insufficiency requiring continous renal replacement therapy. He was diagnosed with advanced HIV (HIV RNA 470 000 copies/mL; CD4 13 cells/mm3; CD4% 15.1%), TB and fungal endophthalmitis. He had also severe bowel dysmotility requiring a parenteral regimen for all treatments. The patient was started on IV TB treatment including rifampicin, amikacin, moxifloxacin and linezolid in addition to liposomal amphotericin for his disseminated histoplasmosis and fungal endophthalmitis. The amphotericin was transitioned to posaconazole due to pancytopenia. Despite the bowel dysmotility, an oral antiretroviral treatment was tried via nasogastric tube. However this resulted in intolerability therefore IM cabotegravir (600 mg) and rilpivirine (900 mg) plus IV 1 mg/kg zidovudine administered every 4 hours were initiated. Plasma cabotegravir and rilpivirine were measured 7 days post injection. The cabotegravir concentration was 455 ng/mL and therefore below the minimal concentration target (664 ng/mL) whereas rilpivirine was below the limit of quantification. The patient died 48 days after initial presentation due to multi-organ failure. This case shows that the coadministration with strong inducers leads to sub-therapeutic levels of injectable cabotegravir and rilpivirine and therefore should be avoided.

This case was published by Sunagawa SW et al. in Open Forum Infect Dis 2023.