Evaluating the efficacy and safety of letermovir compared to valganciclovir for the prevention of human cytomegalovirus disease in adult lung transplant recipients.

BACKGROUND: Lung transplant recipients are at high risk for severe cytomegalovirus (CMV) disease. Off-label use of letermovir (LET) may avert myelotoxicity associated with valganciclovir (VGCV), but data in lung transplantation are limited. This study aims to evaluate the outcomes of LET prophylaxis among lung transplant recipients. METHODS: This retrospective, matched cohort study included lung transplant recipients who received LET for primary CMV prophylaxis following VGCV intolerance. Patients were matched 1:1 to historical VGCV controls based on age, serostatus group, and time from transplant. The primary outcome was CMV breakthrough within 1 year post-LET initiation; secondary outcomes included hematologic changes. RESULTS: A total of 124 lung transplant recipients were included per group (32% CMV mismatch, D+R-), with LET initiated a median of 9.6 months post-transplantation. One CMV breakthrough event (0.8%) was observed in the LET group versus four (3.2%) in the VGCV group (p = .370). The median (interquartile range) white blood cell (WBC) count was 3.1 (2.1-5.6) at LET initiation which increased to 5.1 (3.9-7.2) at the end of follow-up (p <.001). For VGCV controls, WBC was 4.8 (3.4-7.2) at baseline and 5.4 (3.6-7.2) at the end of follow-up; this difference was not statistically significant (p = .395). Additionally, 98.4% of LET patients experienced ≥1 leukopenia episode in the year prior to LET compared to 71.8% the year after initiation (p <.001). Similar results were observed for neutropenia (48.4% and 17.7%, p <.001). CONCLUSION: LET prophylaxis was associated with a low rate of CMV reactivation and leukopenia recovery. LET may represent a reasonable prophylaxis option for lung transplant recipients unable to tolerate VGCV.

Rapid administration of undiluted loading doses of levetiracetam.

OBJECTIVE: Rapid administration of antiseizure medications is a critical concept in the treatment of status epilepticus. Although undiluted levetiracetam (LEV) doses of up to 2500 mg have been evaluated, minimal data exist to support the safety of loading doses up to 4500 mg. This study will evaluate intravenous (IV) push administration of undiluted LEV from 2500 to 4500 mg for safety outcomes as well as tolerability. METHODS: This is a retrospective, observational, cohort analysis of adult patients who received at least one loading dose of undiluted IV push LEV from October 15, 2019, to April 30, 2022, at a large academic medical center in Phoenix, Arizona. Relevant outcomes include the safety and tolerability of rapid administration of undiluted LEV at higher loading doses. RESULTS: We evaluated 518 loading doses in 518 unique patients included during the study period. LEV was a new medication for witnessed or suspected seizures in 80.3% of patients, with 31.2% having a documented history of epilepsy or seizure disorder. At the time of LEV administration, 52.9% of patients were on a general medicine floor, 34.3% were in the intensive care unit, and 12.7% were in the emergency department. The median loading dose of LEV was 3600 mg (3000-4000 mg), with 4000 mg being the most common loading dose given. Peripheral IV lines were documented as the only available line in 78.6% of patients for loading dose administration. No adverse events associated with LEV administration were documented. SIGNIFICANCE: Rapid IV administration of undiluted doses of LEV is both safe and tolerable in loading doses of 2500-4500 mg, allowing for rapid drug administration in the setting of status epilepticus.