Development of a simple high-performance liquid chromatography-ultraviolet method for sotorasib quantification in human plasma: Implications for therapeutic drug monitoring.

Sotorasib, an oral small-molecule inhibitor, reportedly exerts promising activity against Kirsten rat sarcoma viral oncogene homolog (KRAS)-mutant tumors. However, the currently administered dose may fail to represent the optimal dose based on the therapeutic efficacy. Herein, we developed a simple and sensitive method using high-performance liquid chromatography with ultraviolet (HPLC-UV) to measure the sotorasib concentration in human plasma. The sotorasib calibration curve exhibited linearity across the concentration range of 0.10-20.0 µg/mL (r2 = 0.9999). The coefficients of intra- and inter-day validation ranged between 0.79-9.75% and 3.01-6.13%, respectively. The assay accuracy ranged between -3.14 and 5.18%, with > 98.5% recovery. Subsequently, we applied the developed method to estimate sotorasib concentrations in a patient with KRAS G12C-mutated non-small cell lung cancer. We anticipate that our HPLC-UV method will be valuable for assessing the safety and efficacy of sotorasib in larger patient cohorts.

[Efficacy and safety of concomitant use of rabeprazole during dual-antiplatelet therapy with clopidogrel and aspirin after drug-eluting stent implantation: a retrospective cohort study].

After coronary stent implantation, dual-antiplatelet therapy (DAT), such as aspirin and clopidogrel, is essential to prevent stent thrombosis. Proton-pump inhibitors (PPIs) may be used to prevent gastrointestinal (GI) bleeding during DAT, but there is no evidence for the efficacy of PPIs in this setting. Because both clopidogrel and PPIs are metabolized by cytochrome P450 (CYP) 2C19, there is a possibility that, through drug interaction, PPIs diminish the antiplatelet effect of clopidogrel. In this retrospective cohort study, we evaluated the efficacy and safety of rabeprazole in patients receiving DAT of clopidogrel and aspirin after drug-eluting stent implantation. In 199 patients treated with DAT alone (control group) and 103 patients treated with rabeprazole plus DAT (rabeprazole group), we examined the incidences of GI bleeding and major adverse cardiac events (MACE) including stent thrombosis. The incidence of GI bleeding was not significantly different between the groups (hazard ratio 0.47 [95% confidence interval 0.15-1.42], P=0.18; P=0.17 in log-rank test), although no patient with severe bleeding was observed in the rabeprazole group. The use of rabeprazole did not increase the incidence of MACE (hazard ratio 1.28 [95% confidence interval 0.54-3.00], P=0.56; P=0.56 in log-rank test). One patient who developed subacute stent thrombosis under DAT was genetically proven to be a CYP2C19 poor metabolizer. The effect of rabeprazole to prevent GI bleeding is limited in patients receiving DAT. It remains to be confirmed whether these results may depend on CYP2C19 polymorphisms or a class of PPIs.

[A case of therapy for bevacizumab-induced hypertension].

The patient was a 73-year-old female with sigmoid colon cancer, who underwent resection of sigmoid colon cancer and liver metastasis. She was treated with 5-fluorouracil and levofolinate calcium(sLV5FU2)plus bevacizumab(BV) for advanced colorectal cancer. She was treated with angiotensin II receptor blocker(ARB)because hersystolic blood pressure was 200 mmHg and her diastolic blood pressure 100 mmHg after five courses of BV therapy. As a result, her blood pressure was controlled. It was possible to administer BV. Therefore, ARB may be the preferred antihypertensive agent in the management of BV-induced hypertension.