Analysis of the first therapeutic-target-achieving time of warfarin therapy and associated factors in patients with pulmonary embolism

Ultrasound-triggered herceptin liposomes for breast cancer therapy

The functionalization of liposomes with monoclonal antibodies is a potential strategy to increase the specificity of liposomes and reduce the side-effects associated with chemotherapeutic agents. The active targeting of the Human Epidermal growth factor Receptor 2 (HER2), which is overexpressed in HER2 positive breast cancer cells, can be achieved by coating liposomes with an anti-HER2 monoclonal antibody. In this study, we synthesized calcein and Doxorubicin-loaded immunoliposomes functionalized with the monoclonal antibody Trastuzumab (TRA). Both liposomes were characterized for their size, phospholipid content and antibody conjugation. Exposing the liposomes to low-frequency ultrasound (LFUS) triggered drug release which increased with the increase in power density. Trastuzumab conjugation resulted in enhancing the sensitivity of the liposomes to LFUS. Compared to the control liposomes, TRA-liposomes showed higher cellular toxicity and higher drug uptake by the HER2 + cell line (SKBR3) which was further improved following sonication with LFUS. Combining immunoliposomes with LFUS is a promising technique in the field of targeted drug delivery that can enhance efficiency and reduce the cytotoxicity of antineoplastic drugs.

Effectiveness and safety of rivaroxaban versus warfarin in obese patients with acute venous thromboembolism: analysis of electronic health record data

There is limited data evaluating clinical outcomes of rivaroxaban versus warfarin in obese patients with venous thromboembolism (VTE). Our objective was to evaluate the effectiveness and safety of rivaroxaban versus warfarin in obese VTE patients. We performed a cohort analysis using Optum® De-Identified Electronic Health Record data from 11/1/2012 to 9/30/2018. Patients with a body mass index (BMI) ≥ 30 kg/m² admitted to the hospital, emergency department or observation unit for VTE, prescribed rivaroxaban or warfarin as their first oral anticoagulant (OAC) within 7-days and had ≥12-months of EHR activity prior were included. We excluded patients with OAC use at baseline or cancer. Patients were 1:1 matched (standard differences<0.10). Primary outcomes were recurrent VTE and major bleeding at 3-, 6- and 12-months using an intent-to-treat approach. Subanalyses of BMI 30.0-34.9, 35.0-39.9 and ≥ 40 kg/m² were performed. Risk was compared using Cox regression and reported as hazard ratios (HRs) with 95% confidence intervals (CI). We identified 6755 rivaroxaban and 6755 warfarin users with BMI ≥ 30 kg/m² and incident VTE. At 3-, 6- and 12-months, rivaroxaban was associated with a reduced hazard of recurrent VTE compared to warfarin (HR 0.61, 95%CI   0.51-0.72; HR 0.65, 95%CI  0.55-0.77; HR 0.63, 95%CI  0.54-0.74) with no difference in major bleeding (HR  0.99, 95%CI  0.68-1.44; HR 0.90, 95%CI  0.64-1.26; HR 1.00, 95%CI  0.73-1.36). No statistical difference was found across BMI categories for either recurrent VTE (p-interaction≥0.43) or major bleeding (p-interaction ≥ 0.58) at any time point. In obese VTE patients, prescription of rivaroxaban was associated with a significantly reduced risk of recurrent VTE versus warfarin, without impacting major bleeding. Our findings remained consistent across BMI classes.

Impact of genetic and clinical factors on warfarin therapy in patients early after heart valve replacement surgery

PURPOSE

Factors influencing responsiveness to warfarin at treatment onset time were not well identified in Chinese patients undergoing heart valve replacement. We sought to select the most relevant factors that associated with patient response to warfarin early after heart valve surgery.

METHODS

In this observational study, 289 patients starting warfarin therapy early after heart valve replacement surgery were enrolled. CYP2C9 *1, *2, *3, and *5; VKORC1-1639 G>A, CYP4F2 V433M, and GGCX rs11676382 genotypes; clinical characteristics, response to therapy, and bleeding and thrombosis events were collected. The primary outcomes were the time to the first INR equal to or more than lower limit of therapeutic range and the warfarin dose requirements. Stepwise multiple linear regression was performed to develop a dosing algorithm to predict the warfarin dose requirements.

RESULTS

The results of univariate analysis showed lone VKORC1-1639 G>A, CYP2C9 *1/*3, cefazolin, cefoperazone-sulbactam, increased BMI, Δhemoglobin, and white blood cell count could significantly affect patient responsiveness to warfarin in the initial period of anticoagulation. Multivariate analysis resulted in an equation: Accumulated warfarin doses (mg) = 17.068 VKORC1-1639 G>A - 4.261 hypertension + 0.593 BMI - 0.115 age - 4.852 CYP2C9 *1/*3 - 2.617 cefazolin - 4.902 cefoperazone-sulbactam - 4.537, which could explain 40.2% of the variability in warfarin dose needed to reach the first INR equal to or more than lower limit of therapeutic range.

CONCLUSIONS

Both genetic and clinical factors contributed to anticoagulation effect of warfarin in the initial period of treatment. Our findings could provide a basis for the personalized management of warfarin use in the early stage of anticoagulation in northern Chinese patients.