The Food and Drug Administration has approved the first injectable complete therapy for adults with HIV-1. Cabenuva, a two-drug copackaged product of cabotegravir (Vocabria), an HIV-1 integrase strand transfer inhibitor, and rilpivirine (Edurant), an HIV-1 nonnucleoside reverse transcriptase inhibitor, is administered once a month as two intramuscular injections. The drug combination is approved for use in adults whose HIV has been virologically suppressed (HIV-1 RNA less than 50 copies per milliliter) through antiretroviral therapy, and who are on a stable antiretroviral regimen without treatment failure or known or suspected resistance to either cabotegravir or rilpivirine.
Prior to starting cabotegravir and rilpivirine injections, patients should receive oral cabotegravir and oral rilpivirine for approximately one month to ensure the drugs are well tolerated. Intramuscular treatment should begin on the last day of oral treatment. Although the daily pill burden for most people with HIV has decreased over the years, some people may still find a daily oral regimen difficult to follow and a once-a-month injection may be preferred. Because Cabenuva is considered complete HIV treatment, no other HIV drug therapy should be used while the patient is receiving cabotegravir and rilpivirine injections.
The safety and efficacy of cabotegravir and rilpivirine injections were established in two randomized, multicenter, active-controlled, parallel-arm, open-label, noninferiority phase 3 trials with a total of 1,182 virologically suppressed HIV-infected adults. Patients in both trials continued to show virologic suppression at the conclusion of each study, and no clinically relevant change from baseline in CD4+ cell counts was observed.
The labeling for extended-release injectable cabotegravir-rilpivirine warns of the risk of hypersensitivity reactions to rilpivirine or other integrase inhibitors. Some serious postinjection reactions are possible; these would occur within minutes of rilpivirine injection and include dyspnea, agitation, abdominal cramping, flushing, sweating, oral numbness, and changes in blood pressure. The labeling also warns that hepatotoxicity has been reported, so monitoring of liver chemistry during therapy is recommended. Depressive disorders (depressed mood, depression, major depression, mood alteration, mood swings, unusual mood, feeling tense, negative thoughts, or suicidal ideation or attempt) are also a risk.
The most common adverse reactions to extended-release injectable cabotegravir-rilpivirine were injection site reactions (pain, erythema, tenderness, pruritus, and local swelling), fever, fatigue, headache, musculoskeletal pain, nausea, sleep disorders, dizziness, and rash.
Cabenuva packaging contains a vial each for cabotegravir and rilpivirine. The vials do not need to be reconstituted or further diluted. Nurses administering cabotegravir and rilpivirine injections should know that the drugs should not be mixed in one syringe and the two injections should be given on opposite sides of the body into a gluteal muscle (the ventral gluteal muscle is preferred). Nurses should use the Z-tract technique when administering the injections to minimize leakage from the injection site. Either drug can be administered first.
Although some residual concentration of cabotegravir and rilpivirine may remain in the patient's system for up to 12 months, another regimen should be started no later than one month after the final injection to maintain full antiretroviral suppression. If there are planned missed or delayed injections (by more than seven days), then oral therapy should be prescribed to replace up to two consecutive monthly injections. Unplanned episodes of missed or delayed injections will need retitration of the drug dose.
Nurses should teach patients about the potential adverse effects of treatment. Patients should be advised that any changes in mood warrant immediate medical evaluation. To assess for serious, though transient, postinjection adverse effects, nurses should monitor the patient for about 10 minutes after administration and provide appropriate treatment if needed.
For complete prescribing information for Cabenuva, see http://www.accessdata.fda.gov/drugsatfda_docs/label/2021/212888s000lbl.pdf.