Impact of letermovir prophylaxis in CMV reactivation and disease after allogenic hematopoietic cell transplantation: a real-world, observational study

Letermovir for CMV prevention in CMV-seropositive adults undergoing allo-HCT was implemented at our program in 2021. This study investigates the results from the use of letermovir. The study includes all the 140 CMV-seropositive patients who underwent an allo-HCT during the years 2020, 2021, and 2022 at our institution. Thirty-eight (27.4%) of these patients received letermovir, administered from day + 7 to day + 100 and restarted if patients were on treatment with steroids. The day + 180 and 1-year cumulative incidences of CMV reactivation were 5.3% and 12.1% for patients who received letermovir and 52.9% and 53.9% for those who did not (P < 0.001) (HR 0.19, P < 0.001). Four (10.5%) of these thirty-eight patients had a CMV reactivation, but only 2 (5.3%) cases occurred during the administration of letermovir. During the first year after allo-HCT, 13 (9.2%) patients had CMV disease; the day + 180 and 1-year cumulative incidences were 2.6% and 6.0% for patients who received letermovir and 9.9% and 12.3% for those who did not (P = 0.254) (HR 1.01, P = 0.458). Two (4.2%) of the patients included in the letermovir group had CMV disease, but both of them after letermovir discontinuation. Letermovir induced a protective effect on CMV reactivation risk, but its use was not associated with a significant reduction of CMV disease. The fact that the CMV disease in patients who received letermovir occurred after the discontinuation of the drug, questions whether CMV prophylaxis should be used in patients with high risk for CMV reactivation or disease.

At-Home Foscarnet Administration in Patients with Cytomegalovirus Infection Post-Allogeneic Stem Cell Transplantation: A Unicentric, Safe, and Feasible Program

Cytomegalovirus (CMV) infection is a relevant cause of morbimortality in patients receiving allogeneic stem cell transplantation (allo-HCT). Foscarnet (FCN) is an effective drug against CMV administered intravenously and usually on an inpatient basis. The Home Care Unit (HCU) for hematologic patients at our hospital designed an at-home FCN administration model to avoid the hospitalization of patients requiring FCN treatment. This study analyzes whether the at-home administration of FCN is as safe and effective as its hospital administration. We collected and compared demographic, clinical, analytical, and economic data of patients with CMV infection post-allo-HCT who received FCN in the hospital (n = 16, 17 episodes) vs. at-home (n = 67, 88 episodes). The proportions of patients with cured CMV infections were comparable between the two groups (65.9% vs. 76.5%, p = 0.395). The median duration of FCN treatment was 15 (interquartile range [IQR] 9-23) and 14 (IQR 11-19) days in the HCU and inpatient cohorts, respectively (p = 0.692). There were no significant differences in the FCN toxicities between groups except for hypocalcemia (26.1% vs. 58.8%, p = 0.007), which was more prevalent in the inpatient cohort. A significant cost-effectiveness was found in the HCU cohort, with a median savings per episode of EUR 5270. It may be concluded that home administration of FCN is a safe, effective, and cost-efficient therapeutic option for patients with CMV infection and disease.

Impact of Early Intrapatient Variability of Tacrolimus Concentrations on the Risk of Graft-Versus-Host Disease after Allogeneic Stem Cell Transplantation Using High-Dose Post-Transplant Cyclophosphamide

Tacrolimus (Tac) is a pivotal immunosuppressant agent used to prevent graft-versus-host disease (GVHD) after allogeneic stem cell transplantation (alloHSCT). Tac is characterized by a narrow therapeutic window and a high inter-patient and intra-patient pharmacokinetic variability (IPV). Although high IPV of Tac concentrations has been associated with adverse post-transplant outcomes following solid organ transplantation, the effects of Tac IPV on alloHSCT recipients have not been determined. Tac IPV was therefore retrospectively evaluated in 128 alloHSCT recipients receiving high-dose post-transplant cyclophosphamide (PTCy) and the effects of Tac IPV on the occurrence of acute GVHD (aGVHD) were analyzed. Tac IPV was calculated from pre-dose concentrations (C0) measured during the first month after Tac initiation. The cumulative rates of grades II-IV and grades III-IV aGVHD at day +100 were 22.7% and 7%, respectively. Higher Tac IPV was associated with a greater risk of developing GVHD, with patients having IPV > 50th percentile having significantly higher rates of grades II-IV (34.9% vs. 10.8%; hazard ratio [HR] 3.858, p < 0.001) and grades III-IV (12.7% vs. 1.5%; HR 9.69, p = 0.033) aGVHD than patients having IPV ≤ 50th percentile. Similarly, patients with IPV > 75th percentile had higher rates of grades II-IV (41.9% vs. 16.5%; HR 3.30, p < 0.001) and grades III-IV (16.1% vs. 4.1%; HR 4.99, p = 0.012) aGVHD than patients with IPV ≤ 75th percentile. Multivariate analyses showed that high Tac IPV (>50th percentile) was an independent risk factor for grades II-IV (HR 2.99, p = 0.018) and grades III-IV (HR 9.12, p = 0.047) aGVHD. Determination of Tac IPV soon after alloHSCT could be useful in identifying patients at greater risk of aGVHD.

Gene expression profiles of breast cancer metastasis according to organ site

In advanced breast cancer, biomarker identification and patient selection using a metastatic tumor biopsy is becoming more necessary. However, the biology of metastasis according to the organ site is largely unknown. Here, we evaluated the expression of 771 genes in 184 metastatic samples across 11 organs, including liver, lung, brain, and bone, and made the following observations. First, all PAM50 molecular intrinsic subtypes were represented across organs and within immunohistochemistry-based groups. Second, HER2-low disease was identified across all organ sites, including bone, and HER2 expression significantly correlated with ERBB2 expression. Third, the majority of expression variation was explained by intrinsic subtype and not organ of metastasis. Fourth, subtypes and individual subtype-related genes/signatures were significantly associated with overall survival. Fifth, we identified 74 genes whose expression was organ-specific and subtype-independent. Finally, immune profiles were found more expressed in lung compared to brain or liver metastasis. Our results suggest that relevant tumor biology can be captured in metastatic tissues across a variety of organ sites; however, unique biological features according to organ site were also identified and future studies should explore their implications in diagnostic and therapeutic interventions.

Case Report: A Case Study Documenting the Activity of Atezolizumab in a PD-L1-Negative Triple-Negative Breast Cancer

The immune checkpoint inhibitor atezolizumab is approved for PD-L1-positive triple-negative breast cancer (TNBC). However, no activity of atezolizumab in PD-L1-negative TNBC has been reported to date. Here, we present the case study of a woman with TNBC with low tumor infiltrating lymphocytes and PD-L1-negative disease, which achieved a significant response to atezolizumab monotherapy and durable response after the combination of atezolizumab and nab-paclitaxel. The comprehensive genomic analysis that we performed in her tumor and plasma samples revealed high tumor mutational burden (TMB), presence of the APOBEC genetic signatures, high expression of the tumor inflammation signature, and a HER2-enriched subtype by the PAM50 assay. Some of these biomarkers have been shown to independently predict response to immunotherapy in other tumors and may explain the durable response in our patient. Our work warrants further translational studies to identify biomarkers of response to immune checkpoint inhibitors in TNBC beyond PD-L1 expression and to better select patients that will benefit from immunotherapy.

Safe anti-programmed cell death-1 rechallenge with antibody switching after immune-related adverse events: brief communication

Aim: To evaluate the safety of rechallenge with a different anti-PD-1 antibody after an immune-related adverse event (irAE) that has prompted the discontinuation of anti-PD-1 therapy. Patients & methods: We describe two patients with metastatic melanoma who developed potentially disabling and early irAEs following anti-PD-1 treatment. Therapy was discontinued and toxicities resolved with corticosteroids. Results: Rechallenge switching to an alternative anti-PD-1 antibody did not lead to a new or recurrent irAE. Conclusion: Switching to a different anti-PD-1 antibody when resuming therapy after an irAE might be a safe strategy and warrants further investigation. Structural and biological differences between antibodies might explain the different safety outcomes.

A reproducible and safe at-home allogeneic haematopoietic cell transplant program: first experience in Central and Southern Europe

In 2015, we implemented an at-home allogeneic haematopoietic cell transplant (allo-HCT) program. Between 2015 and 2018, 252 patients underwent allo-HCT; 41 patients underwent allo-HCT in the at-home program (46% myeloablative; 63% unrelated donor; 32% posttransplant cyclophosphamide), and these patients were compared with 39 in-patients; safety, capacity to release beds for other programs, and economic efficiency cost were evaluated. We observed a lower incidence of febrile neutropenia in the at-home group compared with that in the in-patient group (32% versus 90%; p < 0.0001), whereas the incidence of aspergillosis was similar among groups (at-home 1% versus in-patient 3%; p = 0.5). The at-home patients showed a lower incidence of 1-year severe graft-versus-host disease (GVHD; 10% versus 29%; p = 0.03). There were no differences in 1-year transplant-related mortality, relapse, or overall survival among groups. The re-admission rate in the at-home group was 7%. The at-home setting was less expensive (9087 €/transplant), and its implementation increased capacity by 10.5 allo-HCTs/year. Moreover, a chimeric antigen receptor T-cell program could be established without increasing beds. Thus, our at-home allo-HCT program may be a safe modality to reduce febrile neutropenia and acute GVHD, resulting in lower re-admission rates.

Population pharmacokinetics of daptomycin in critically ill patients

Daptomycin has shown activity against a wide range of Gram-positive bacteria; however, the approved dosages usually seem insufficient for critically ill patients. The aim of this study was to develop a population pharmacokinetic model for daptomycin in critically ill patients and to estimate the success of the therapy by applying pharmacokinetic/pharmacodynamic (PK/PD) criteria. Sixteen intensive care unit patients were included, four of whom underwent continuous renal replacement therapies (CRRT). Blood and, when necessary, effluent samples were drawn after daptomycin administration at previously defined time points. A population approach using NONMEM 7.3 was performed to analyse data. Monte Carlo simulations were executed to evaluate the suitability of different dosage regimens. The probabilities of achieving the PK/PD target value associated with treatment success (ratio of the area under the plasma concentration-time curve over 24 h divided by the minimum inhibitory concentration (AUC₂₄/MIC ≥ 666)) and to reach daptomycin concentrations linked to toxicity (minimum concentration at steady-state (Cmin_ss) ≥ 24.3 mg/L) were calculated. The pharmacokinetics of daptomycin was best described by a one-compartment model. Elimination was conditioned by the creatinine clearance (Clcr) and also by the extra-corporeal clearance when patients were subjected to continuous renal replacement therapy (CRRT). The PK/PD analysis confirmed that 280- and 420-mg/d dosages would not be enough to achieve high probabilities of target attainment for MIC values ≥ 1 mg/L in patients with Clcr ≥ 60 mL/min or in subjects with lower Clcrs but receiving CRRT. In these patients, higher dosages (560-840 mg/d) should be needed. When treating infections due to MIC values ≥ 4 mg/L, even the highest dose would be insufficient.

Interactions between oral antineoplastic agents and concomitant medication: a systematic review

INTRODUCTION

In recent years, the number of oral antitumoral agents has considerably increased. Oral administration increases the risk of interactions, because most oral anticancer drugs are taken on a daily basis. Interactions can increase exposure to antitumoral agents or cause treatment failure. Many antitumoral drugs undergo enzymatic metabolism by cytochrome P450. As some act as inducers or inhibitors of one or more isoenzymes, they can lead to decreases or increases in plasma concentrations of concomitant drugs. Hence, cytostatic drugs can act not only as victims but also as perpetrators. P-glycoprotein, an efflux transporter, can also be involved in pharmacokinetic interactions.

AREAS COVERED

A Medline search was performed to summarize the available evidence of the most clinically relevant interactions between oral chemotherapy agents and other drugs. The search covered the period from 1966 until August 2012 for each antitumoral drug using the medical subject headings 'Drug Interactions' OR 'Pharmacokinetics'. While the present review is not exhaustive, it aims to increase clinicians' awareness of potential drug-drug interactions.

EXPERT OPINION

As cancer patients are often polymedicated and treated by different physicians, the risk of drug interactions between antitumoral agents and other medications is high. More clinical interaction studies are encouraged to ensure appropriate antineoplastic pharmacokinetics in clinical practice.

[Antibiotic dose adjustment in the treatment of MRSA infections in patients with acute renal failure undergoing continuous renal replacement therapies]

Acute renal failure is frequent in critically ill patients. In those patients who need renal replacement therapy, continuous techniques are an alternative to intermittent haemodialysis. Critically ill patients often have an infection, which can lead to sepsis and renal failure. An early and adequate antibiotic treatment at correct dosage is extremely important. Methicillin resistant Staphylococcus aureus (MRSA) is a frequent nosocomial pathogen that causes a high rate of morbidity and mortality in critically ill patients. Many antibiotics are easily removed by continuous renal replacement therapies (CRRT) leading to a high risk of under dosing and therapeutic failure or resistance breakthrough. The objective of this review is to assess the clinical evidence on the pharmacokinetics and dosage recommendations of the main antibiotic groups used in MRSA treatment in patients treated with CRRT.

Evaluation of antiretroviral-related errors and interventions by the clinical pharmacist in hospitalized HIV-infected patients

OBJECTIVES

The aim of the study was to identify antiretroviral-related errors in the prescribing of medication to HIV-infected inpatients and to ascertain the degree of acceptance of the pharmacist's interventions.

METHODS

An observational, prospective, 1-year study was conducted in a 750-bed tertiary-care teaching hospital by a pharmacist trained in HIV pharmacotherapy. Interactions with antiretrovirals were checked for contraindicated combinations. Inpatient antiretroviral prescriptions were compared with outpatient dispensing records for reconciliation. Renal and hepatic function was monitored to determine the need for dose adjustments.

RESULTS

The prescriptions for 247 admissions (189 patients) were reviewed. Sixty antiretroviral-related problems were identified in 41 patients (21.7%). The most common problem was contraindicated combinations (n=20; 33.3%), followed by incorrect dose (n=10; 16.7%), dose omission (n=9; 15%), lack of dosage reduction in patients with renal or hepatic impairment (n=6; 10% and n=1; 1.7%, respectively), omission of an antiretroviral (n=6; 10%), addition of an alternative antiretroviral (n=5; 8.3%) and incorrect schedule according to outpatient treatment (n=3; 5%). Fifteen out of 20 errors were made during admission. A multivariate analysis showed that factors associated with an increased risk of antiretroviral-related problems included renal impairment [odds ratio (OR) 3.95; 95% confidence interval (CI) 1.39-11.23], treatment with atazanavir (OR 3.53; 95% CI 1.61-7.76) and admission to a unit other than an infectious diseases unit (OR 2.50; 95% CI 1.28-4.88). Use of a nonnucleoside reverse transcriptase inhibitor was a protective factor (OR 0.33; 95% CI 0.13-0.81). Ninety-two per cent of the pharmacist's interventions were accepted.

CONCLUSION

Antiretroviral-related errors affected more than one-in-five patients. The most common causes of error were contraindicated or not recommended drug-drug combinations and dose-related errors. A clinical pharmacist trained in HIV pharmacotherapy could help to detect errors and reduce the duration of their effect.

[Analysis of the duration of and reasons for changing the first combination of antiretroviral therapy]

OBJECTIVE

To determine the duration of and reasons behind changing the various combinations of drugs used for the initiation of antiretroviral treatment in naïve patients.

METHODS

A retrospective observational study that included all patients with HIV infection who started antiretroviral therapy in a high-tech university reference hospital during the period from 1 January 2003 and 31 December 2005. Patients were followed until 31 December 2008. To estimate the cumulative probability of discontinuation the Kaplan-Meier method was used.

RESULTS

A total of 441 patients were included. The average duration of the first treatment was 384 (interquartile interval 84-1290) days. The regimen based on non-nucleoside reverse transcriptase inhibitors and those that included as nucleosides abacavir or tenofovir in combination with lamivudine or emtricitabine showed a significantly longer duration than the rest. The main reasons for termination were the side effects, although in a lesser percentage than that obtained in previous studies. No associations were found between the rest of the characteristics of the patients or of the treatment and the risk of termination.

DISCUSSION

Although the duration of the first antiretroviral treatment remains short, currently fewer changes are made due to side effects and due to loss to follow-up. The reasons may be better tolerance and less complexity. However, more studies are needed to determine the benefits of one regimen or another, and to be able to generalise the results.