Phase I study of axitinib and everolimus in metastatic solid tumours and extension to metastatic renal cell carcinoma: Results of EVAX study

Safety and activity of vandetanib in combination with everolimus in patients with advanced solid tumors: a phase I study

Background

Preclinical studies suggest that combining vandetanib (VAN), a multi-tyrosine kinase inhibitor of rearranged during transfection (RET) proto-oncogene, vascular endothelial growth factor receptor (VEGFR), and epidermal growth factor receptor (EGFR), with everolimus (EV), a mammalian target of rapamycin (mTOR) inhibitor, may improve antitumor activity. We determined the safety, maximum tolerated dose (MTD), recommended phase II dose (RP2D), and dose-limiting toxicities (DLTs) of VAN + EV in patients with advanced solid cancers and the effect of combination therapy on cancer cell proliferation and intracellular pathways.

Patients and methods

Patients with refractory solid tumors were enrolled in a phase I dose-escalation trial testing VAN (100-300 mg orally daily) + EV (2.5-10 mg orally daily). Objective responses were evaluated using RECIST v1.1. RET mutant cancer cell lines were used in cell-based studies.

Results

Among 80 patients enrolled, 72 (90%) patients were evaluable: 7 achieved partial response (PR) (10%) and 37 had stable disease (SD) (51%; duration range: 1-27 cycles). Clinical benefit (SD or PR ≥ 6 months) was observed in 26 evaluable patients [36%, 95% confidence intervals (CI) (25% to 49%)]. In 80 patients, median overall survival (OS) was 10.5 months [95% CI (8.5-16.1)] and median progression-free survival (PFS) 4.1 months [95% CI (3.4-7.3)]. Six patients (7.5%) experienced DLTs and 20 (25%) required dose modifications. VAN + EV was safe, with fatigue, rash, diarrhea, and mucositis being the most common toxicities. In cell-based studies, combination therapy was superior to monotherapy at inhibiting cancer cell proliferation and intracellular signaling.

Conclusions

The MTDs and RP2Ds of VAN + EV are 300 mg and 10 mg, respectively. VAN + EV combination is safe and active in refractory solid tumors. Further investigation is warranted in RET pathway aberrant tumors.

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VAN + EV is safe, active and provides clinical benefit in some patients with refractory solid cancers.

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Dual therapy is superior to monotherapy at inhibiting proliferation and intracellular signaling of RET mutant cancer cells.

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This study highlights the importance of identifying novel combination therapies to overcome therapeutic resistance.

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Next-generation sequencing of advanced solid tumors may inform treatment strategies and guide future drug development.

Osteonecrosis of the jaws associated with protein kinase inhibitors: a systematic review

This systematic review analysed evidence relating to medication-related osteonecrosis of the jaws (MRONJ) associated with protein kinase inhibitors in antiresorptive naïve patients. A literature search of major biomedical databases was conducted in March 2020. Information extracted from relevant articles included bibliographic information, patient characteristics, MRONJ characteristics at diagnosis, management strategies and outcomes. Sixteen studies, representing data from 17 patients, were included for final analysis. Descriptive statistics were used to synthesis available data. Eleven protein kinase inhibitors were implicated, with a mean exposure of 13 months prior to MRONJ. Renal cell carcinoma was the primary diagnosis in 41.2% of patients. Patient symptoms, clinical features, radiographic findings and histological findings were consistent with those previously described in patients with MRONJ associated with antiresorptive medications. Overall, there was a 75% rate of cure, with a mean healing time of 17.2 weeks. Patients were treated surgically in 53.3% of the cases. Patients treated surgically achieved complete healing in 100% of cases, compared with 58% in those treated conservatively. Drug discontinuation was reported in 69.2% of patients. Patients who had the offending drug discontinued achieved complete healing in 75% of cases, compared with 50% in those who did not. Evidence relating to MRONJ associated with protein kinase inhibitors is of low quality. From the available data, there are notable differences relating to patient characteristics, treatment strategies and outcomes, between MRONJ associated with protein kinase inhibitors compared with antiresorptives. Higher quality evidence is required to support the findings of this review.