Management of the Drug-Drug Interactions Between Valproic Acid and Dolutegravir-A Case Study.

OBJECTIVE: Preliminary evidence shows that concomitant administration of valproic acid can reduce the exposure to dolutegravir with limited clinical impacts. Here, we describe a male living with HIV who experienced a drastic reduction in dolutegravir trough concentrations a few weeks after starting valproic acid treatment as identified by therapeutic drug monitoring. Concomitantly, pharmacists recommended a supplementation of magnesium to improve insomnia. CASE REPORT: A 62-year-old man with HIV on antiretroviral therapy with dolutegravir and lamivudine recently added valproic acid to clonazepam and sertraline to treat severe sleep disturbances. An 84% reduction in dolutegravir trough concentrations was observed compared with the previous outpatient visit (418 versus 2714 ng/mL), with values close to the minimum effective drug concentration (300 ng/mL). Considering this, we strongly discourage the use of magnesium. CONCLUSIONS: We are confident that our findings can contribute to a better understanding of the clinical problems that infectious disease physicians encounter in their daily management of people with HIV and how therapeutic drug monitoring may add value in this context. This case also highlights the importance of multidisciplinary services for the optimal management of polypharmacy in people with HIV.

Effect of Carbamazepine on Darunavir Trough Concentrations: When the Dose Can Make the Difference-A Case Study.

BACKGROUND: Carbamazepine (CBZ) is an antiseizure medication known to induce the expression of cytochrome P4503A metabolic enzymes. Here, we describe a man living with HIV who underwent several changes in the daily dose of CBZ, which resulted in different induction effects on darunavir trough concentrations. METHODS: A 59-year-old man with HIV, successfully undergoing maintenance antiretroviral treatment with darunavir/cobicistat once daily (combined with raltegravir), was prescribed CBZ for recurrent trigeminal neuralgia. Over subsequent months, the patient underwent various changes in the doses (from 200 to 800 mg/d) and trough concentrations (from 3.6 to 18.0 mg/L) of CBZ, guided by clinical response to trigeminal neuralgia. RESULTS: A highly significant inverse association was observed between darunavir trough concentration and both CBZ dose or trough concentration (coefficient of determination >0.75, P < 0.0001). Ultimately, the darunavir dose was increased to 600 mg twice daily with ritonavir and dolutegravir to ensure optimal antiretroviral coverage, anticipating potential further uptitration of CBZ doses. CONCLUSIONS: The impact of CBZ on boosted darunavir exposure seemed to be dose- and concentration-dependent. The management of such drug-drug interactions in daily practice was facilitated through therapeutic drug monitoring. This case underscores the importance of a multidisciplinary approach that incorporates both antiretroviral and nonantiretroviral comedications contributing to the optimal management of polypharmacy in individuals living with HIV.

Rilpivirine and cabotegravir trough concentrations in people with HIV on long-term treatment with long-acting injectable antiretrovirals.

OBJECTIVE: Large inter-individual variability in the pharmacokinetics of rilpivirine and cabotegravir has been reported in the first weeks after starting long-acting injectable (LAI) therapy. Here, we assessed the distribution of rilpivirine and cabotegravir trough concentrations in people with HIV (PWH) on long-term LAI treatment. METHODS: Adult PWH treated with LAI for at least 32 weeks with an assessment of drug plasma trough concentrations were considered. The proportion of rilpivirine and cabotegravir plasma trough concentrations below four-times the protein-adjusted concentrations required for 90% inhibition of viral replication (4×PA-IC90) was estimated. RESULTS: Sixty-seven PWH were identified. LAI treatment duration was 216 ±â€Š80 weeks (range 32-320 weeks). Cabotegravir concentrations were associated with lower inter-individual variability compared with rilpivirine (45% versus 84%; P < 0.05). No differences were found in rilpivirine (160 ±â€Š118 versus 189 ±â€Š81 ng/mL; P = 0.430) and cabotegravir (1758 ±â€Š807 versus 1969 ±â€Š802 ng/mL; P = 0.416) trough concentrations in males (n = 55) versus females (n = 12). A non-significant trend for lower cabotegravir concentrations was found in PWH with a body mass index >30 kg/m2 (n = 9) versus non-obese participants (1916 ±â€Š905 versus 1606 ±â€Š576 ng/mL; P = 0.131). Three out of the 67 PWH had at least one drug concentration <4×PA-IC90: 100% of PWH had undetectable HIV viral load. CONCLUSIONS: At steady state, optimal systemic exposure of cabotegravir and rilpivirine was found in most PWH; cabotegravir trough concentrations were associated with lower inter-individual variability compared with rilpivirine. The study was not powered to assess the contribution of sex and/or body weight on LAI exposure due to the small number of females and obese PWH included.

Management of Polypharmacy and Potential Drug-Drug Interactions in Patients with Pulmonary Aspergillosis: A 2-Year Study of a Multidisciplinary Outpatient Clinic.

Pulmonary aspergillosis mainly affects elderly patients, patients with pulmonary complications, patients with hematological malignancies, organ transplant recipients, or critically ill patients. Co-morbidities may result in a high rate of polypharmacy and a high risk of potential drug-drug interaction (pDDI)-related antifungal azoles, which are perpetrators of several pharmacokinetic- and pharmacodynamic-driven pDDIs. Here, we report the results of the first 2-year study of an outpatient clinic focusing on the management of therapies in patients with pulmonary aspergillosis. All patients who underwent an outpatient visit from May 2021 to May 2023 were included in this retrospective analysis. A total of 34 patients who were given an azole as an antifungal treatment (53% voriconazole, 41% isavuconazole, and 6% itraconazole) were included. Overall, 172 pDDIs were identified and classified as red- (8%), orange- (74%), or yellow-flag (18%) combinations. We suggested handling polypharmacy in those patients using specific diagnostic and pharmacologic interventions. As expected, red-flag pDDIs involved mainly voriconazole as a perpetrator (71%). However, nearly 30% of red-flag pDDIs were not related to antifungal therapy. These findings highlight the importance of conducting an overall assessment of the pharmacologic burden and the key role played by a multidisciplinary team for the optimization of therapies in patients with pulmonary aspergillosis.

Optimizing the antiretroviral treatment focusing on long-term effectiveness and a person-centered approach. Consensus Guidance Using a Delphi Process.

Definitive data on the long-term success of the latest antiretroviral therapy (ART) strategies are still lacking. A panel of infectious diseases specialists was convened to develop a consensus on how to tailor and follow ART over time. Panelists used a Delphi technique to develop a list of statements describing preferred management approaches for ART and patient monitoring and quality of life evaluation. Ninety infectious diseases specialists from several Infectious Diseases Centers in Italy participated in the consensus process. A consensus was reached on virological and immunological parameters to use to monitor long-term efficacy of antiretroviral treatment, while there was no consensus on the use of specific inflammation and immune-activation markers in clinical routine. The panel agreed on the need for an antiretroviral treatment with the lowest impact on bone, kidney and cardiovascular toxicity and on the utility of quality-of-life monitoring during the standard follow up of people living with HIV. The consensus statements developed by a panel of infectious diseases specialists may provide guidance to practitioners for a person-centered approach aimed at obtaining long-term virological and clinical success for people living with HIV.

No effects of nirmatrelvir/ritonavir on darunavir plasma trough concentrations: a case report.

COVID-19 may be associated with worst outcomes in people living with HIV compared with HIV-negative patients. Nirmatrelvir/ritonavir can be safely co-administered with all the HIV antiretroviral drugs, without considering dose adjustment. However, no studies have formally investigated the effect of a double booster (ritonavir plus cobicistat) regimen on darunavir concentrations. We presented a case describing the lack of effects of adding nirmatrelvir/ritonavir on darunavir plasma trough concentrations in a patient with HIV already on treatment with a booster-based antiretroviral regimen. We believe this could be a reassuring message for physicians, allowing them to prevent unnecessary denial of COVID-19 treatment or inappropriate discontinuation of co-medications in patients with HIV.

Different effects of the companion antiretroviral drugs on dolutegravir trough concentrations.

BACKGROUND: Dolutegravir is widely used in different dual and triple antiretroviral regimens. Here, we sought to investigate the effect of the companion antiretroviral drug(s) on dolutegravir plasma trough concentrations in persons with HIV, with a focus on dual regimens. METHODS: Dolutegravir concentrations collected from October 2015 to March 2023 ( n  = 900) were stratified according to the main antiretroviral classes (NRTIs, NNRTIs, protease inhibitors) and according to single drugs. Dolutegravir concentrations measured in persons with HIV concomitantly treated with lamivudine were considered as the reference group. RESULTS: Dolutegravir trough concentrations were significantly higher in persons with HIV given protease inhibitors compared with the reference [1886 (1036-2940) versus 1575 (1026-2226) ng/ml; P  = 0.004]. The highest dolutegravir concentrations were measured in persons with HIV concomitantly treated with unboosted atazanavir [2908 (2130-4135) ng/ml]. Conversely, co-administration of darunavir/ritonavir resulted in significantly lower dolutegravir exposure [909 (496-1397) ng/ml; P  = 0.002 versus reference]. Among NNRTIs, the higher dolutegravir concentrations were measured in presence of rilpivirine [2252 (1489-2686); P  < 0.001 versus reference]. CONCLUSION: Dolutegravir trough concentrations are differently affected by individual antiretroviral drugs, with some drug combinations (i.e. dolutegravir/darunavir/cobicistat, or dolutegravir/rilpivirine) providing significantly higher than expected dolutegravir exposure. Such combinations might be advantageous when there are concerns about dolutegravir plasma exposure or resistance.

Doravirine Plus Integrase Strand Transfer Inhibitors as a 2-Drug Treatment-Switch Strategy in People Living with HIV: The Real-Life DORINI Multicentric Cohort Study.

BACKGROUND: Few data are available about the efficacy, durability, and tolerability of doravirine (DOR) + integrase strand inhibitors (INI) as a switching strategy among antiretroviral therapy (ART)-experienced people living with HIV (PLWH). SETTING: Retrospective, multicenter cohort study investigating the durability, efficacy, and tolerability of 2 off-label drug associations of DOR + INI among ART-experienced PLWH. METHODS: The study included PLWH who switched to DOR combined with either raltegravir (RAL) or dolutegravir (DTG) between June 1, 2020, and December 31, 2021, with at least 1 follow-up (FU) visit. Virologic, biometric, and metabolic parameters were evaluated at baseline (T0) and at 1-3 (T1), 6 (T2), and 12 (T3) months. Univariate and multivariate survival analyses assessed the 28-week probability of persistence on the regimens. Patient satisfaction was measured using the HIV Treatment Satisfaction Questionnaire. RESULTS: Ninety-five PLWH were included, 52 in DOR + RAL and 43 in DOR + DTG. Six treatment discontinuations were reported during a mean of 37 (±17) weeks of FU (incidence of 2.7 × 1000 person-weeks FU). Only 2 were the result of virological failure without resistance mutations. DOR + DTG demonstrated significantly higher 28-week persistence than DOR + RAL (HR 1.90, 95% CI: 1.24-2.90, log-rank: P = 0.003). Weight, waist circumference, and fasting lipids reduced considerably at T3 vs T0. Overall, high satisfaction with the new treatment was reported, particularly in the DOR + RAL (68 (64-72)/72), compared with the DOR + DTG group (58 (50-65)/72, P < 0.001). CONCLUSIONS: Our experience revealed few treatment discontinuations, improved metabolic parameters, and high patient satisfaction among ART-experienced PLWH switching to DOR combined with INI, irrespective of the specific INI used.

Physicochemical Characteristics of Antimicrobials and Practical Recommendations for Intravenous Administration: A Systematic Review.

Most antimicrobial drugs need an intravenous (IV) administration to achieve maximum efficacy against target pathogens. IV administration is related to complications, such as tissue infiltration and thrombo-phlebitis. This systematic review aims to provide practical recommendations about diluent, pH, osmolarity, dosage, infusion rate, vesicant properties, and phlebitis rate of the most commonly used antimicrobial drugs evaluated in randomized controlled studies (RCT) till 31 March 2023. The authors searched for available IV antimicrobial drugs in RCT in PUBMED EMBASE®, EBSCO® CINAHL®, and the Cochrane Controlled Clinical trials. Drugs' chemical features were searched online, in drug data sheets, and in scientific papers, establishing that the drugs with a pH of <5 or >9, osmolarity >600 mOsm/L, high incidence of phlebitis reported in the literature, and vesicant drugs need the adoption of utmost caution during administration. We evaluated 931 papers; 232 studies were included. A total of 82 antimicrobials were identified. Regarding antibiotics, 37 reach the "caution" criterion, as well as seven antivirals, 10 antifungals, and three antiprotozoals. In this subgroup of antimicrobials, the correct vascular access device (VAD) selection is essential to avoid complications due to the administration through a peripheral vein. Knowing the physicochemical characteristics of antimicrobials is crucial to improve the patient's safety significantly, thus avoiding administration errors and local side effects.

Pillars of long-term antiretroviral therapy success.

BACKGROUND: Meeting the challenge of antiretroviral therapy (ART) whose efficacy can last a lifetime requires continuous updating of the virological, pharmacological, and quality of life outcomes to be pursued and a continuous review of literature data on the efficacy and tolerability of new drugs and therapeutic strategies. METHODS: With the aim of identifying open questions and answers about the current controversies in modern ART, we adapted the Design Thinking methodology to the needs of the design phase of a scientific article, involving a team of experts in HIV care. RESULTS: Five main pillars of treatment success were discussed: sustained virologic suppression over time; immunological recovery; pharmacological attributes; long-term tolerability and safety of ART; and people's satisfaction and quality of life. The definition of the outcomes to be achieved in each thematic area and the tools to achieve them were reviewed and discussed. CONCLUSIONS: Long-term treatment success should be intended as a combination of HIV-RNA suppression, immune recovery, and high quality of life. To achieve this, the regimen should be well-tolerated, with high potency, genetic barrier, and forgiveness, and should be tailored by a person-centered perspective, based on individual needs, preferences, and therapeutic history.

Management of Polypharmacy and Potential Drug-Drug Interactions in Patients with Mycobacterial Infection: A 1-Year Experience of a Multidisciplinary Outpatient Clinic.

In 2022, we opened an outpatient clinic for the management of polypharmacy and potential drug-drug interactions (pDDIs) in patients with mycobacterial infection (called GAP-MyTB). All patients who underwent a GAP-MyTB visit from March 2022 to March 2023 were included in this retrospective analysis. Fifty-two patients were included in the GAP-MyTB database. They were given 10.4 ± 3.7 drugs (2.8 ± 1.0 and 7.8 ± 3.9 were, respectively, antimycobacterial agents and co-medications). Overall, 262 pDDIs were identified and classified as red-flag (2%), orange-flag (72%), or yellow-flag (26%) types. The most frequent actions suggested after the GAP-MyTB assessment were to perform ECG (52%), therapeutic drug monitoring (TDM, 40%), and electrolyte monitoring (33%) among the diagnostic interventions and to reduce/stop proton pump inhibitors (37%), reduce/change statins (14%), and reduce anticholinergic burden (8%) among the pharmacologic interventions. The TDM of rifampicin revealed suboptimal exposure in 39% of patients that resulted in a TDM-guided dose increment (from 645 ± 101 to 793 ± 189 mg/day, p < 0.001). The high prevalence of polypharmacy and risk of pDDIs in patients with mycobacterial infection highlights the need for ongoing education on prescribing principles and the optimal management of individual patients. A multidisciplinary approach involving physicians and clinical pharmacologists could help achieve this goal.

Polypharmacy and Aging in People Living with HIV: 6 Years of Experience in a Multidisciplinary Outpatient Clinic.

BACKGROUND: Despite the availability of potent antiretroviral drugs, the management of human immunodeficiency virus (HIV) infection still presents some important challenges, especially in older patients who often experience age-related comorbidities and complex polypharmacy. OBJECTIVE: To describe the results of our 6 year experience with the outpatient clinic [Gestione Ambulatoriale Politerapie (GAP)] for the management of polypharmacy in people living with HIV (PLWH). METHODS: Demographic characteristics, antiretroviral regimens, and number and type of comedications were collected in all PLWH included in the database of GAP from September 2016 to September 2022. Therapies were stratified based on the number of anti-HIV drugs (dual versus triple regimens) and on the presence of pharmacokinetic boosters (ritonavir or cobicistat). RESULTS: A total of 556 PLWH were included in the GAP database. Overall, the enrolled patients were administered 4.2 ± 2.7 drugs (range 1-17) in addition to antiretroviral therapies. The number of comedications greatly increased with age (3.0 ± 2.2 versus 4.1 ± 2.5 versus 6.3 ± 3.2 in PLWH aged < 50 versus 50-64 versus > 65 years; p < 0.001 for all comparisons). PLWH on dual antiretroviral therapies were significantly older (58 ± 9 versus 54 ± 11 years; p < 0.001) and were concomitantly treated with more drugs (5.1 ± 3.2 versus 3.8 ± 2.5; p < 0.001) compared with those on triple therapies. A significant reduction of boosted antiretroviral regimens (53% versus 23%; p < 0.001) and in the number of comedications (4.0 ± 2.9 versus 3.1 ± 2.2 drugs; p < 0.001) was observed in the subgroup of patients (n = 198) with two GAP visits. CONCLUSIONS: The high prevalence of polypharmacy in PLWH, especially among older adults, place these patients at high risk for clinically relevant drug-drug interactions (DDIs). A multidisciplinary approach involving physicians and clinical pharmacologists could help to optimize medication regimens associated with reduced risk.