Evaluation of Dolutegravir- and Bictegravir-Based Antiretroviral Regimen Utilization in Patients who Cannot Take Medications by Mouth

A retrospective review of patients unable to take medications by mouth showed short interruptions of therapy for most patients. In a secondary analysis, our data showed maintenance and/or achievement of viral suppression for most patients. A retrospective review of intensive care patients unable to take antiretrovirals by mouth showed 56.6% of patients experiencing a transient interruption in therapy. Additionally, our case series further supports previous literature on crushing dolutegravir and bictegravir regimens to maintain and achieve viral suppression.

A clinical review of HIV integrase strand transfer inhibitors (INSTIs) for the prevention and treatment of HIV-1 infection

Integrase strand transfer inhibitors (INSTIs) have improved the treatment of human immunodeficiency virus (HIV). There are currently four approved for use in treatment-naïve individuals living with HIV; these include first generation raltegravir, elvitegravir, and second generation dolutegravir and bictegravir. The most recent INSTI, cabotegravir, is approved for (1) treatment of HIV infection in adults to replace current antiretroviral therapy in individuals who maintain virologic suppression on a stable antiretroviral regimen without history of treatment failure and no known resistance to its components and (2) pre-exposure prophylaxis in individuals at risk of acquiring HIV-1 infection. Cabotegravir can be administered intramuscularly as a monthly or bi-monthly injection depending on the indication. This long-acting combination has been associated with treatment satisfaction in clinical studies and may be helpful for individuals who have difficulty taking daily oral medications. Worldwide, second generation INSTIs are preferred for treatment-naïve individuals. Advantages of these INSTIs include their high genetic barrier to resistance, limited drug-drug interactions, excellent rates of virologic suppression, and favorable tolerability. Few INSTI resistance-associated mutations have been reported in clinical trials involving dolutegravir, bictegravir and cabotegravir. Other advantages of specific INSTIs include their use in various populations such as infants and children, acute HIV infection, and individuals of childbearing potential. The most common adverse events observed in clinical studies involving INSTIs included diarrhea, nausea, insomnia, fatigue, and headache, with very low rates of treatment discontinuation versus comparator groups. The long-term clinical implications of weight gain associated with second generation INSTIs dolutegravir and bictegravir warrants further study. This review summarizes key clinical considerations of INSTIs in terms of clinical pharmacology, drug-drug interactions, resistance, and provides perspective on clinical decision-making. Additionally, we summarize major clinical trials evaluating the efficacy and safety of INSTIs in treatment-naïve patients living with HIV as well as individuals at risk of acquiring HIV infection.

Crushed bictegravir/emtricitabine/tenofovir alafenamide in a human immunodeficiency virus-positive patient with pancreatic cancer

We present the case of a 78-year-old African American man with a history of human immunodeficiency virus diagnosed in 2007 who was newly diagnosed with pancreatic cancer. A percutaneous endoscopic gastrostomy tube was placed during the initial inpatient visit of pancreatic cancer diagnosis due to persistent dysphagia. Due to PEG placement and the patient's wish to continue his previous antiretroviral therapy, the patient crushed his fixed-dose bictegravir/emtricitabine/tenofovir alafenamide under the direction of a physician and has maintained virologic suppression.

Antiretroviral Therapy Management in Adults With HIV During ICU Admission

The extended lifespan of people living with human immunodeficiency (HIV) and acquired immune deficiency syndrome (AIDS) (PLWHA) has increased the potential for ICU admissions unrelated to HIV infection. The objective of this review is to guide continued management of antiretroviral therapy (ART) recommended by the United States Department of Health and Human Services Antiretroviral Guidelines in critically ill adult PLWHA admitted to the intensive care unit (ICU). Pharmacists are uniquely positioned to mitigate these concerns, including whether to continue ART in the ICU, drug interactions with common ICU drugs, renal and hepatic dosing considerations, and alternative methods of administration. Despite these concerns, the original ART regimen should be continued or modified in conjunction with an HIV specialist. Discontinuation greater than 2 weeks should be avoided due to potential resistance and future HIV treatment failure. Use of ART in critically ill patients presents challenges that pharmacists are best equipped to address to prevent adverse events, administration errors, and treatment failure.

Sustained virologic suppression with abacavir, emtricitabine, and crushed dolutegravir and tenofovir alafenamide in a patient with HIV and eosinophilic esophagitis

We report the use of crushed dolutegravir (DTG) and tenofovir alafenamide (TAF) tablets in a 27-year-old man with progressive dysphagia due to eosinophilic esophagitis, which severely limited compliance, leading to viral resistance. Based on his drug resistance history, allergies, and inability to swallow tablets intact, he was transitioned to DTG 50 mg (crushed), TAF 25 mg (crushed), liquid abacavir (20 mg/ml) 30 ml, and liquid emtricitabine (10 mg/ml) 24 ml orally daily. After receiving this regimen for five months, the patient’s HIV viral load decreased from 9910 to 59 copies/ml and after ten total months became suppressed at <20 copies/ml. Our case report suggests administration of crushed DTG and TAF tablets may be a viable option for patients with dysphagia and limited treatment options.

The effect of veno-arterial extracorporeal oxygenation and nasogastric tube administration on the pharmacokinetic profile of abacavir, lamivudine and dolutegravir: a case report

BACKGROUND

Pharmacokinetic (PK) changes can affect antiretroviral (ARV) systemic exposure for critically ill patients living with HIV (CI-PLWH). Studies to guide ARV adjustments in this population are limited.

METHODS

A PK analysis was conducted in a 44-year-old CI-PLWH who presented for a heart and lung transplant on veno-arterial extracorporeal membrane oxygenation (VA ECMO). Home ARV therapy (ART) of co-formulated abacavir/lamivudine/dolutegravir (ABC/3TC/DTG) was continued. ARV serum concentrations were obtained during and after VA ECMO. Two blood levels were drawn at 1 h, for maximum serum concentration (C_max) and a serum trough (C_t). ARVs were given as a single tablet crushed via nasogastric tube.

RESULTS

Area under the concentration-time curve (AUC_0-t) was calculated using non-compartmental analysis. C_max and AUC_0-t were higher during VA ECMO compared with post-decannulation. The C_max of ABC was >2.5-fold higher than the mean in the reference. C_max and C_t post VA ECMO were within range of referenced literature for all ARVs. C_max and AUC_0-t of DTG post VA ECMO was approximately four- to fivefold lower than referenced literature. HIV virological suppression was maintained throughout the hospitalization.

CONCLUSIONS

ART adjustments would not be required for this patient. Additional studies are needed to assess effects of VA ECMO and crushed tube administration of ARVs in CI-PLWH.

Crushing of dolutegravir fixed-dose combination tablets increases dolutegravir exposure

Background

If HIV patients are unconscious or cannot swallow tablets for other reasons, antiretroviral medication is crushed and dissolved prior to administration. Crushing can alter drug exposure, possibly leading to treatment failure, development of resistance or toxicity. Currently, there is no information about crushing of the branded fixed-dose combination of dolutegravir/abacavir/lamivudine (Triumeq®, referred to as TRI); therefore, crushing of TRI is not recommended.

Objectives

To investigate whether the TRI fixed-dose combination tablet can be crushed and combined with enteral nutrition without influencing pharmacokinetics (PK).

Methods

We carried out an open-label, three-period, randomized, single-dose, crossover trial in 22 healthy adult volunteers. Subjects randomly received whole-tablet TRI with fasting (reference), crushed and suspended TRI with fasting or crushed and suspended TRI with oral intake of enteral nutrition. Bioequivalence criteria (80%-125% acceptance range) of AUC0-∞ and Cmax were used. ClinicalTrials.gov: NCT02569346.

Results

Crushing TRI leads to higher dolutegravir exposure (AUC0-∞: +26% and Cmax: +30%) and, if crushed TRI is combined with enteral nutrition, to a decrease in abacavir Cmax (-17%). Lamivudine concentrations were not affected as geometric mean ratios with 90% CIs fell within the 80%-125% range.

Conclusions

Bioequivalence could not be demonstrated for a crushed and suspended tablet or a crushed and suspended tablet with oral intake of enteral nutrition compared with whole-tablet TRI with fasting. Both scenarios led to higher dolutegravir exposure, but this did not exceed exposure after intake with food or in twice-daily dosing. In our opinion, TRI can be crushed for patients with swallowing difficulties and can be simultaneously administered with enteral nutrition.

Crushed dolutegravir/abacavir/lamivudine given via nasogastric tube in gastric outlet obstruction caused by cancer resulted in rapid viral load suppression

Alternative modes of antiretroviral administration are sought for people with impaired intestinal passage and/or absorption. We present a case of late HIV diagnosis (CD4+ count 160 cells/µL) with gastric outlet obstruction due to stomach adenocarcinoma. Co-morbidities included oesophageal candidiasis, Helicobacter pylori-positive duodenal ulcers and cytomegalovirus duodenitis. The gastric outlet obstruction required total parenteral nutrition and parenteral medication during four weeks of diagnostic work-up leading to pyloric resection. Crushed dolutegravir, abacavir and lamivudine were administered during this time in the evening via nasogastric tube, which was kept clamped overnight. The tube was unclamped in the morning and stomach content was drained during the daytime. This mode of administration resulted in rapid and sustained viral load suppression (from 300,000 to 115 copies per mL in 28 days, 81 copies/mL after 42 days of treatment and less than 40 copies/mL thereafter). Therapeutic drug monitoring confirmed sufficient antiretroviral plasma levels during this mode of administration. The absorption of crushed dolutegravir, abacavir and lamivudine in the stomach may be considered in people with questionable gastrointestinal passage or impaired gastric emptying to achieve viral load suppression.