Date of report 03 Feb 2020

Reported case interaction between
Cobicistat and ERGOTAMINE

A 33-year-old HIV-infected man on treatment with elvitegravir/cobicistat, emtricitabine, tenofovir-DF presented at the emergency room with severe pain and paresthesias at both calves and feet. The clinical examination showed bilateral and symmetrical feet paleness and coldness. Femoral pulse was present in both legs. A vascular Doppler showed a severe stenosis of the superficial femoral arteries of both legs and the blood tests revealed a creatine phosphokinase elevation (649 UI/mL) in the context of ischaemia. The medication history revealed the use ergotamine for the past 5 days for the treatment of migraine. The patient was diagnosed with arterial ischaemia in relation with ergotism caused by cobicistat inhibition of CYP3A4 mediated metabolism of ergotamine. Ergotamine was stopped and antiretroviral treatment was changed to rilpivirine, emtricitabine and tenofovir-DF. Furthermore, the patient received treatment with low molecular weight heparin and intravenous prostaglandins. After these interventions, distal pulses recovered and ischaemic signs regressed. The concomitant administration of boosted antiretroviral drugs and ergotamine is contra-indicated due to the risk of ergotism. This case has been publsihed by Navarro J et al. Antivir Ther 2017; 22(1):89-90.