Since BIC came to market, we've been routinely using it and at least half our patients take that medication either as new diagnoses or switch patients. Unfortunately, we've all started noticing that several of these patients have occasional or even persistent low-level viremia in the 20-200 range. Clinically, I know this doesn't matter, but it does cause anxiety in patients and it generally involves one of us asking if the patient was experiencing any illness when the lab was drawn, asking about adherence, looking at potential interactions with MVIs or other products. And we're of course concerned if the VL does go up >200. We haven't noticed this issue with other medications and have many people of DTG/F/TAF who aren't experiencing this.
At first, I assumed some non-adherence, maybe some divalent cation interactions, poor absorption, or something related to taking the med. But many of these patients were consistently <20 on previous regimens without resistance to bic. Now that so many folks have independently noticed this and it's occurring so frequently, I'm wondering if this is a lab issue? We can only run VLs twice a week, so it's not uncommon for a patient to have his/her/their lab drawn and it need to be stored for 3-4 days prior to the test. When I asked our lab, they couldn't think of a plausible cause though.
Has anyone, particularly those without the ability to get daily VL testing, noticed this phenomenon too?
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Katy Garrett, PharmD, BCIDP, AAHIVP
Clinical Pharmacist
Portland ME
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