Academy Exchange

 View Only
Expand all | Collapse all

Impact of Switching to Long-Acting Injectable Cabotegravir Plus Rilpivirine on Rectal HIV-1 RNA Shedding and Implications for Transmission Risk

  • 1.  Impact of Switching to Long-Acting Injectable Cabotegravir Plus Rilpivirine on Rectal HIV-1 RNA Shedding and Implications for Transmission Risk

    Posted 05-06-2025 19:15

    Does the attached research indicate that U = U is no longer the case.

    Is the transmission risk significant? What are the experts saying about this study?

    Impact of Switching to Long-Acting Injectable Cabotegravir Plus Rilpivirine on Rectal HIV-1 RNA Shedding and Implications for Transmission Risk 

    Background. The impact of long-acting injectable cabotegravir plus rilpivirine (CAB/RPV) on rectal human immunodeficiency virus 1 (HIV-1) RNA dynamics and the factors associated with viral shedding remain poorly understood.

    Methods. This prospective study evaluated HIV-1 RNA dynamics by analyzing sequential paired plasma and rectal fluid samples from virologically suppressed individuals who transitioned from oral antiretroviral therapy (ART) to every-2-month CAB/RPV (preceded or not by oral lead-in), over a 9-month follow-up period. RPV trough concentrations were measured in 384 rectal samples.

    Results. In total, 597 plasma and 561 rectal samples from 90 participants were analyzed. HIV-1 RNA >50 (>1.69 log10) copies/ swab was detected in 14.7% (59/401) of rectal samples (42.2% of participants) during intramuscular CAB/RPV, and in 17.5% (28/160) of rectal samples (29% of participants) during oral ART. Median detectable rectal HIV-1 RNA level during intramuscular ART was 362 (range, 133–2216) copies/swab. The frequency and quantity of rectal shedding did not differ between groups with/without oral lead-in. No correlation was observed between rectal shedding and detectable plasma HIV-1 RNA. Median rectal RPV concentration was 3.07 (quartile 1–quartile 3, 2.83–3.35) log10 ng/swab, 1.6-fold above the 90% maximum effective concentration (EC90) for rectal tissue, and did not correlate with rectal HIV-1 RNA levels. Rectal shedding was associated with plasma pre-ART HIV-1 RNA >5 log10 in multivariate Cox regression, but was unrelated to established predictors of virological failure with CAB/RPV.

    Conclusions. Rectal HIV-1 shedding is common during bimonthly intramuscular CAB/RPV treatment and is also observed with oral ART. Shedding was independent of concurrent plasma HIV-1 RNA and rectal RPV concentrations, and was associated with pre- ART viral load.



    ------------------------------
    Paul Debes
    Pittsburgh PA
    ------------------------------


  • 2.  RE: Impact of Switching to Long-Acting Injectable Cabotegravir Plus Rilpivirine on Rectal HIV-1 RNA Shedding and Implications for Transmission Risk

    Posted 05-07-2025 15:22

    Interesting study, and so does this mean we must tell patients that undetectable does not mean untransmissible?

    And as I said in past would anyone have unprotected sexual relations with a undetectable hiv patient who is + and on hiv meds?



    ------------------------------
    Patrick Aufiero
    Long Beach Township NJ
    ------------------------------



  • 3.  RE: Impact of Switching to Long-Acting Injectable Cabotegravir Plus Rilpivirine on Rectal HIV-1 RNA Shedding and Implications for Transmission Risk

    Posted 05-07-2025 15:56

    There's nothing new here. Long before U=U, we knew that plasma viral load did not completely predict tissue levels. There was well-described discordance between plasma viral load and the amount of virus in semen, for example. However, there were no documented cases of transmission when plasma viral load was undetectable, and multiple large clinical studies (HPTN 052, PARTNER, PARTNER2, Opposites Attract) subsequently confirmed the absence of transmission in thousands of serodiscordant partnerships. Such studies are far more powerful than studies like this. The U=U message still stands!



    ------------------------------
    Joel Gallant, MD, MPH
    Johns Hopkins University
    Baltimore, MD

    AXCES Research Group
    Santa Fe, NM
    ------------------------------