Assessments of CYP‑inhibition‑based drug-drug interaction between vonoprazan and poziotinib in vitro and in vivo

CONTEXT

Poziotinib and vonoprazan are two drugs mainly metabolized by CYP3A4. However, the drug-drug interaction between them is unknown.

OBJECTIVE

To study the interaction mechanism and pharmacokinetics of poziotinib on vonoprazan.

MATERIALS AND METHODS

In vitro experiments were performed with rat liver microsomes (RLMs) and the contents of vonoprazan and its metabolite were then determined with UPLC-MS/MS after incubation of RLMs with vonoprazan and gradient concentrations of poziotinib. For the in vivo experiment, rats in the poziotinib treated group were given 5 mg/kg poziotinib by gavage once daily for 7 days, and the control group was only given 0.5% CMC-Na. On Day 8, tail venous blood was collected at different time points after the gavage administration of 10 mg/kg vonoprazan, and used for the quantification of vonoprazan and its metabolite. DAS and SPSS software were used for the pharmacokinetic and statistical analyses.

RESULTS

In vitro experimental data indicated that poziotinib inhibited the metabolism of vonoprazan (IC₅₀ = 10.6 μM) in a mixed model of noncompetitive and uncompetitive inhibition. The inhibitory constant K_i was 0.574 μM and the binding constant αK_i was 2.77 μM. In vivo experiments revealed that the AUC_(0-T) (15.05 vs. 90.95 μg/mL·h) and AUC_(0-∞) (15.05 vs. 91.99 μg/mL·h) of vonoprazan increased significantly with poziotinib pretreatment. The MRT_(0-∞) of vonoprazan increased from 2.29 to 5.51 h, while the CLz/F value decreased from 162.67 to 25.84 L/kg·h after pretreatment with poziotinib.

CONCLUSIONS

Poziotinib could significantly inhibit the metabolism of vonoprazan and more care may be taken when co-administered in the clinic.

Efficacy and safety of olaparib in advanced ovarian cancer: a meta-analysis

This study aimed to evaluate the efficacy and safety of olaparib for the treatment of advanced ovarian cancer. All studies that assessed the efficacy and safety of olaparib in advanced ovarian cancer were searched in PubMed, Embase, and Web of Science from their inception to 20 September 2022. The analysis included six studies and 2016 patients. Olaparib could significantly prolong the progression-free survival (PFS) of patients compared to that of the control group (HR = 0.49, 95% CI = 0.36 - 0.68). However, no statistically significant differences were detected in overall survival (OS) and objective response rate (ORR) between the olaparib and control groups. Olaparib treatment increased the number of grade ≥3 adverse events (AEs) in patients with advanced ovarian cancer compared with that in the control group. Olaparib significantly prolonged PFS in patients with advanced ovarian cancer; however, no statistically significant differences were detected in OS and ORR. In terms of safety, olaparib has manageable adverse effects.

A review of progress in o-aminobenzamide-based HDAC inhibitors with dual targeting capabilities for cancer therapy

Histone deacetylases, as a new class of anticancer targets, could maintain homeostasis by catalyzing histone deacetylation and play important roles in regulating the expression of target genes. Due to the fact that simultaneous intervention with dual tumor related targets could improve treatment effects, researches on innovative design of dual-target drugs are underway. HDAC is known as a "sensitizer" for the synergistic effects with other anticancer-target drugs because of its flexible structure design. The synergistic effects of HDAC inhibitor and other target inhibitors usually show enhanced inhibitory effects on tumor cells, and also provide new strategies to overcome multidrug resistance. Many research groups have reported that simultaneously inhibiting HDAC and other targets, such as tubulin, EGFR, could enhance the therapeutic effects. The o-aminobenzamide group is often used as a ZBG group in the design of HDAC inhibitors with potent antitumor effects. Given the prolonged inhibitory effects and reduced toxic side effects of HDAC inhibitors using o-aminobenzamide as the ZBG group, the o-aminobenzamide group is expected to become a more promising alternative to hydroxamic acid. In fact, o-aminobenzamide-based dual inhibitors of HDAC with different chemical structures have been extensively prepared and reported with synergistic and enhanced anti-tumor effects. In this work, we first time reviewed the rational design, molecular docking, inhibitory activities and potential application of o-aminobenzamide-based HDAC inhibitors with dual targeting capabilities in cancer therapy, which might provide a reference for developing new and more effective anticancer drugs.

Efficacy, safety, and correlative biomarkers of bintrafusp alfa in recurrent or metastatic nasopharyngeal cancer patients: a phase II clinical trial

Background

The strategy of dual blockade of TGF-β and PD-L1 pathways has not been previously tested in platinum-refractory recurrent or metastatic nasopharyngeal cancer (R/M NPC) patients. This study aimed to evaluate the safety and efficacy of bintrafusp alfa in refractory R/M NPC patients.

Methods

In this single-arm, single-centre phase II clinical trial, 38 histologically confirmed R/M NPC patients were enrolled and administered with bintrafusp alfa every 2 weeks. Primary endpoint was objective response rate (ORR) per Response Evaluation Criteria in Solid Tumors version 1.1 (RECIST v1.1). Secondary endpoints included progression-free survival (PFS), overall survival (OS), duration of response (DOR), and safety.

Findings

Thirty-eight patients were accrued (33 men; median age, 54 years). ORR was 23.7% (complete response, n = 2; partial response, n = 7). The median DOR was 19.2 months, median PFS was 2.3 months, median OS was 17.0 months, and 1-year OS rate was 63.2%. Unfortunately, 25 patients (65.7%) progressed within 8 weeks of treatment, 15 patients (39.5%) and 8 patients (21.1%) developed hyper-progressive disease (HPD) per RECIST v1.1 and tumor growth rate (TGR) ratio respectively. Sixteen patients (42.4%) experienced ≥ grade 3 treatment-related adverse events (TRAEs), most commonly anemia (n = 9, 23.7%) and secondary malignancies (n = 4, 10.5%). TRAEs led to permanent treatment discontinuation in 7 patients. Patients with strong suppression of plasma TGFβ1 level at week 8 were unexpectedly associated with worse ORR (9.1% vs 44.4%, P = 0.046) and development of HPD. There was no correlation between PD-L1 expression and ORR.

Interpretation

Bintrafusp alfa demonstrated modest activity in R/M NPC but high rates of HPD and treatment discontinuation secondary to TRAEs are concerning.

Funding

The project was supported by Alice Ho Miu Ling Nethersole Charity Foundation Professorship Endowed Fund and Merck KGaA.

Role of microsatellite instability and HER2 positivity in locally advanced esophago-gastric cancer patients treated with peri-operative chemotherapy

PURPOSE

Neoadjuvant chemotherapy (NAC) significantly improved the prognosis of patients with locally advanced gastric cancer (LAGC). Several biomarkers, including HER2 and MMR/MSI are crucial for treatment decisions in the advanced stage but, currently, no biomarkers can guide the choice of NAC in clinical practice. Our aim was to evaluate the role of MSI and HER2 status on clinical outcomes.

METHODS

We retrospectively collected LAGC patients treated with NAC and surgery +/- adjuvant chemotherapy from 2006 to 2018. HER2 and MSI were assessed on endoscopic and surgical samples. Pathologic complete response (pCR) rate, overall survival (OS), and event-free survival (EFS) were estimated and evaluated for association with downstaging and MSI.

RESULTS

We included 76 patients, 8% were classified as MSI-H, entirely consistent between endoscopic and surgical samples. Six percent of patients were HER2 positive on endoscopic and 4% on surgical samples. Tumor downstaging was observed in 52.5% of cases, with three pCR (5.1%), none in MSI-H cancers. According to MSI status, event-free survival (EFS) and overall survival (OS) were higher for MSI-H patients to MSS [EFS not reached vs 30.0 months, p = 0.08; OS not reached vs 39.6 months, p = 0.10].

CONCLUSION

Our work confirms the positive prognostic effect of MSI-H in the curative setting of LAGC, not correlated with pathologic tumor downstaging. Prospective ad-hoc trial and tumor molecular profiling are eagerly needed.

Immune checkpoint inhibitors and cellular immunotherapy for advanced gastric, gastroesophageal cancer: a long pathway

Although the incidence rate and mortality of gastric/gastroesophageal cancer (G/GEJC) are declining globally, G/GEJC remains a health issue in East Asia. When diagnosed as advanced stage, treatment after serial lines of chemotherapy is limited, with a median overall survival of less than 1 year. Immunotherapy, including immune checkpoint inhibitors (ICIs) and cellular immunotherapy, has changed the prospects of cancer therapy by reversing immune suppression in the tumor microenvironment. As part of this review, we enumerated the clinical uses of ICIs related to the immunosuppressive signaling axis PD-1/PD-L1 and CTLA-4/B7. ICIs were initially approved as a secondary treatment option for patients with severe pretreating advanced gastric and gastroesophageal cancer (AG/GEJC). Till now, it has become the mainstream therapy in combination with chemotherapy and targeted therapy for patients identified by biomarkers. Numerous evidence showed microsatellite instability (MSI), programmed cell death ligand 1 (PD-L1) expression, tumor mutation burden (TMB) and Epstein-Barr virus (EBV) status might be indicative to the use of ICIs. In addition, we discussed the current limitations and prospects of ICIs in AG/GGEJC, as well as the first clinical application of novel CAR-T cell therapies.

Quantitative proteomics profiling reveals the inhibition of trastuzumab antitumor efficacy by phosphorylated RPS6 in gastric carcinoma

BACKGROUND

The anti-HER2 antibody trastuzumab is a standard treatment for gastric carcinoma with HER2 overexpression, but not all patients benefit from treatment with HER2-targeted therapies due to intrinsic and acquired resistance. Thus, more precise predictors for selecting patients to receive trastuzumab therapy are urgently needed.

METHODS

We applied mass spectrometry-based proteomic analysis to 38 HER2-positive gastric tumor biopsies from 19 patients pretreated with trastuzumab (responders n = 10; nonresponders, n = 9) to identify factors that may influence innate sensitivity or resistance to trastuzumab therapy and validated the results in tumor cells and patient samples.

RESULTS

Statistical analyses revealed significantly lower phosphorylated ribosomal S6 (p-RPS6) levels in responders than nonresponders, and this downregulation was associated with a durable response and better overall survival after anti-HER2 therapy. High p-RPS6 levels could trigger AKT/mTOR/RPS6 signaling and inhibit trastuzumab antitumor efficacy in nonresponders. We demonstrated that RPS6 phosphorylation inhibitors in combination with trastuzumab effectively suppressed HER2-positive GC cell survival through the inhibition of the AKT/mTOR/RPS6 axis.

CONCLUSIONS

Our findings provide for the first time a detailed proteomics profile of current protein alterations in patients before anti-HER2 therapy and present a novel and optimal predictor for the response to trastuzumab treatment. HER2-positive GC patients with low expression of p-RPS6 are more likely to benefit from trastuzumab therapy than those with high expression. However, those with high expression of p-RPS6 may benefit from trastuzumab in combination with RPS6 phosphorylation inhibitors.

An immuno-magnetophoresis-based microfluidic chip to isolate and detect HER2-Positive cancer-derived exosomes via multiple separation

Exosomes are useful for cancer diagnosis and monitoring. However, clinical samples contain impurities that complicate direct analyses of cancer-derived exosomes. Therefore, a microfluidic chip-based magnetically labeled exosome isolation system (MEIS-chip) was developed as a lab-on-a-chip platform for human epidermal growth factor receptor 2 (HER2)-positive cancer diagnosis and monitoring. Various magnetic nanoclusters (MNCs) were synthesized with different degrees of magnetization, and antibodies were introduced to capture HER2-overexpressing and common exosomes using immunoaffinity. MNC-bonded exosomes were separated into different exits according to their magnetization degrees. The MEIS-chip efficiently separated HER2-overexpressing exosomes from common exosomes that did not contain disease-related information. The simultaneous separation of HER2-and non-HER2-overexpressing exosomes provided a means of analyzing high-purity HER2-overexpressing exosomes while minimizing the contribution of non-target exosomes, reducing misdiagnosis risk. Notably, common exosomes served as a negative control for monitoring real-time changes in HER2 expression. These findings support the application of MEIS-chip for cancer diagnosis and treatment monitoring via effective exosome isolation.