Phase I/II study of single-agent lenvatinib in children and adolescents with refractory or relapsed solid malignancies and young adults with osteosarcoma (ITCC-050)☆

Lenvatinib Plus Ifosfamide and Etoposide in Children and Young Adults With Relapsed Osteosarcoma: A Phase 2 Randomized Clinical Trial

Importance

The combination of ifosfamide and etoposide (IE) is commonly used to treat relapsed or refractory osteosarcoma; however, second-line treatment recommendations vary across guidelines.

Objective

To evaluate whether the addition of lenvatinib to IE (LEN-IE) improves outcomes in children and young adults with relapsed or refractory osteosarcoma.

Design, Setting, and Participants

The OLIE phase II, open-label, randomized clinical trial was conducted globally across Europe, Asia and the Pacific, and North America. From March 22, 2020, through November 11, 2021, the trial enrolled patients aged 2 to 25 years with high-grade osteosarcoma, measurable or evaluable disease per Response Evaluation Criteria in Solid Tumors, version 1.1 (RECIST 1.1), and 1 to 2 prior lines of systemic treatment. The data analyses were performed between March 22, 2020 (first patient in) and June 22, 2022 (data cutoff for the primary analysis), and September 29, 2023 (end of study final database lock).

Interventions

The OLIE trial assessed the efficacy and safety of lenvatinib (14 mg/m2 taken orally once daily) combined with up to 5 cycles of ifosfamide (3000 mg/m2 intravenously) and etoposide (100 mg/m2 intravenously) on days 1 to 3 of each cycle vs IE alone at the same doses. Patients randomized to IE could cross over to receive lenvatinib upon disease progression by independent imaging review.

Main Outcomes and Measures

The primary end point was progression-free survival (PFS) per RECIST 1.1 by independent imaging review. The Kaplan-Meier method was used to estimate the PFS distribution, with a prespecified 1-sided significance threshold of .025 by stratified log-rank test. Secondary end points included PFS rate at 4 months and overall survival. Adverse events were summarized using descriptive statistics.

Results

A total of 81 patients were enrolled (median [IQR] age, 15.0 [12.0-18.0] years; 46 males [56.8%]), with 40 in the LEN-IE arm and 41 in the IE arm. Median PFS was 6.5 months (95% CI, 5.7-8.2 months) for the LEN-IE arm and 5.5 months (95% CI, 2.9-6.5 months) for the IE arm (hazard ratio [HR], 0.54; 95% CI, 0.27-1.08; 1-sided P = .04). The rate of PFS at 4 months was 76.3% (95% CI, 59.3%-86.9%) in the LEN-IE arm and 66.0% (95% CI, 47.7%-79.2%) in the IE arm. Median overall survival was 11.9 months (95% CI, 10.1 months to not estimable) with LEN-IE and 17.4 months (95% CI, 14.2 months to not estimable) with IE (HR, 1.28; 95% CI, 0.60-2.70; 1-sided nominal P = .75). Grade 3 or higher treatment-related adverse events occurred in 35 of 39 patients (89.7%) in the LEN-IE arm and 31 of 39 patients (79.5%) in the IE arm.

Conclusions and Relevance

Although LEN-IE did not meet prespecified statistical significance for improved PFS vs IE, this study demonstrates the importance of international collaboration and randomized clinical trials in patients with relapsed or refractory osteosarcoma and may inform future trial design.

Trial Registration

ClinicalTrials.gov Identifier: NCT04154189.

Efficacy and Safety of Fruquintinib-Based Treatment in Patients with Refractory Bone and Soft Tissue Sarcoma after Developing Resistance to Several TKIs: A Multicenter Retrospective Study

OBJECTIVE

Multitargeted tyrosine kinase inhibitors (TKIs) have been approved as second-line therapy in refractory sarcoma, prolonging progression-free survival (PFS) but with short-lived duration of disease control. Fruquintinib is a TKI that specifically inhibits vascular endothelial growth factor receptor-1,2,3 with no metabolism by liver enzymes. In this retrospective study, we assessed the efficacy and safety of fruquintinib-based treatment in patients with refractory sarcoma after developing several lines of TKI resistance.

METHODS

We retrospectively analyzed the clinical data of patients with refractory sarcoma after they had developed several lines of resistance to TKIs and who received fruquintinib-based treatment from November 2021 to August 2023. The primary endpoint was the progression-free survival rate at 4 months (4m-PFSR). Secondary endpoints were the median PFS, overall survival (OS), objective response rate, disease control rate, and adverse effects (AEs). PFS and OS were estimated using the Kaplan-Meier method. A log-rank test was used to compare survival curves between different clinical and pathological factors. Cox proportional hazards analysis was performed to identify PFS-related prognostic factors.

RESULTS

We included 124 patients: 56 (45.2%) with osteosarcoma, 28 (22.6%) with Ewing sarcoma, seven (5.6%) with chondrosarcoma, and 33 (26.6%) with soft tissue sarcomas (STS). Only 18 (14.5%) patients received monotherapy with fruquintinib. With a median follow-up time of 6.8 (interquartile range [IQR], 4.6-9.4) months, 22 (17.7%) patients had partial response and 78 (62.9%) had stable disease. The 4m-PFSR was 58.4% (95% confidence interval [CI], 49.6%-67.1%). The median PFS and OS were 4.4 (95% CI, 3.9-5.0) months and 11.4 (95% CI, 10.3-12.5) months. In multivariate analysis, a high hazard ratio for progression was associated with target lesions located outside the lung and bone with 1.79 (95% CI, 1.10-2.93; p = 0.020). Eighty-eight AEs were recorded in 47 (37.9%) patients; the most common were pneumothorax (18/124, 14.5%), diarrhea (8/124, 6.5%), oral mucositis (7/124, 5.6%), and thrombocytopenia (7/124, 5.6%).

CONCLUSIONS

Fruquintinib may be a potential option for patients with refractory sarcoma after developing several lines of TKI resistance, with a satisfactory efficacy and safety profile in combination therapy. However, the degree of contribution of fruquintinib to results is unclear when combined with other effective substances. Additional prospective trials of fruquintinib should be conducted, especially involving different pathological types and combination regimens.

Targeted anti-angiogenesis therapy for advanced osteosarcoma

To date, despite extensive research, the prognosis of advanced osteosarcoma has not improved significantly. Thus, patients experience a reduced survival rate, suggesting that a reevaluation of current treatment strategies is required. Recently, in addition to routine surgery, chemotherapy and radiotherapy, researchers have explored more effective and safer treatments, including targeted therapy, immunotherapy, anti-angiogenesis therapy, metabolic targets therapy, and nanomedicine therapy. The tumorigenesis and development of osteosarcoma is closely related to angiogenesis. Thus, anti-angiogenesis therapy is crucial to treat osteosarcoma; however, recent clinical trials found that it has insufficient efficacy. To solve this problem, the causes of treatment failure and improve treatment strategies should be investigated. This review focuses on summarizing the pathophysiological mechanisms of angiogenesis in osteosarcoma and recent advances in anti-angiogenesis treatment of osteosarcoma. We also discuss some clinical studies, with the aim of providing new ideas to improve treatment strategies for osteosarcoma and the prognosis of patients.

Biological Sample Collection to Advance Research and Treatment: A Fight Osteosarcoma Through European Research and Euro Ewing Consortium Statement

Osteosarcoma and Ewing sarcoma are bone tumors mostly diagnosed in children, adolescents, and young adults. Despite multimodal therapy, morbidity is high and survival rates remain low, especially in the metastatic disease setting. Trials investigating targeted therapies and immunotherapies have not been groundbreaking. Better understanding of biological subgroups, the role of the tumor immune microenvironment, factors that promote metastasis, and clinical biomarkers of prognosis and drug response are required to make progress. A prerequisite to achieve desired success is a thorough, systematic, and clinically linked biological analysis of patient samples, but disease rarity and tissue processing challenges such as logistics and infrastructure have contributed to a lack of relevant samples for clinical care and research. There is a need for a Europe-wide framework to be implemented for the adequate and minimal sampling, processing, storage, and analysis of patient samples. Two international panels of scientists, clinicians, and patient and parent advocates have formed the Fight Osteosarcoma Through European Research consortium and the Euro Ewing Consortium. The consortia shared their expertise and institutional practices to formulate new guidelines. We report new reference standards for adequate and minimally required sampling (time points, diagnostic samples, and liquid biopsy tubes), handling, and biobanking to enable advanced biological studies in bone sarcoma. We describe standards for analysis and annotation to drive collaboration and data harmonization with practical, legal, and ethical considerations. This position paper provides comprehensive guidelines that should become the new standards of care that will accelerate scientific progress, promote collaboration, and improve outcomes.

From biology to personalized medicine: Recent knowledge in osteosarcoma

High-grade osteosarcoma is the most common paediatric bone cancer. More than one third of patients relapse and die of osteosarcoma using current chemotherapeutic and surgical strategies. To improve outcomes in osteosarcoma, two crucial challenges need to be tackled: 1-the identification of hard-to-treat disease, ideally from diagnosis; 2- choosing the best combined or novel therapies to eradicate tumor cells which are resistant to current therapies leading to disease dissemination and metastasize as well as their favorable microenvironment. Genetic chaos, tumor complexity and heterogeneity render this task difficult. The development of new technologies like next generation sequencing has led to an improvement in osteosarcoma oncogenesis knownledge. This review summarizes recent biological and therapeutical advances in osteosarcoma, as well as the challenges that must be overcome in order to develop personalized medicine and new therapeutic strategies and ultimately improve patient survival.

Identification and prognostic evaluation of differentially expressed long noncoding RNAs associated with immune infiltration in osteosarcoma

Osteosarcoma is a malignant bone cancer that originates from the bone with the strongest invasiveness. Tumor formation strongly correlates with immune cell infiltration into the tumor immune microenvironment (TIME). Therefore, we aimed to identify TIME-related biomarkers as potential prognostic markers of osteosarcoma. The mRNA and long noncoding RNA (lncRNA) transcriptome data of 88 patients with osteosarcoma and the expression profile of GSE99671 were downloaded from The Cancer Genome Atlas and Gene Expression Omnibus, respectively. Immune infiltration scores and types were evaluated using ESTIMATE and CIBERSORT. A linear model was established to identify the differentially expressed genes (DEGs) and lncRNAs (DElncRNAs). Functional enrichment analysis of DEGs was conducted by Gene Ontology, Kyoto Encyclopedia of Genes and Genomes, gene set enrichment analysis, and gene set variation analysis. DElncRNAs were analyzed using a weighted gene co-expression network. Least absolute shrinkage and selection operator regression was applied to screen for prognostic markers. Patient survival was predicted by the risk score and analyzed by receiver operating characteristic curve. Clinical features affecting patient survival were assessed. Immune infiltration positively correlated with osteosarcoma patient survival. Different immune cell infiltrates in patients with osteosarcma may serve as prognostic indicators and targets for immunotherapy. In total, 1125 DEGs, 80 DElncRNAs, and 11 pairs of co-expressed lncRNA-mRNAs were identified. DEGs in the three modules were associated with immune infiltration into the TIME. Four DElncRNAs, namely AC015819.1, AC015911.3, AL365361.1, and USP30-AS1, showed good prognostic ability for osteosarcoma and were positively correlated with the immune score. Tumor metastasis and risk scores alone were good prognostic indicators, and a combination of the two variables can better predict the prognosis of osteosarcoma. We identified four lncRNAs, AC015819.1, AC015911.3, AL365361.1, and USP30-AS1, as potential biomarkers for osteosarcoma prognosis.

Long-term Treatment of Pediatric Metastatic Papillary Thyroid Cancer With Lenvatinib

Papillary thyroid carcinoma (PTC) is the most common pediatric thyroid malignancy and incidence is increasing. Standard treatment for PTC in pediatric patients includes surgical intervention, suppression of TSH with levothyroxine, and radioactive iodine therapy (RAI) in select patients. In the setting of metastatic PTC or PTC refractory to RAI therapy, tyrosine kinase inhibitors (TKIs), such as lenvatinib, may be used. Until recently, experience with these targeted agents were largely limited to adult patients with progressive or refractory PTC. More recently, increased experience with TKI therapy has been reported in the pediatric population, with case reports and small series describing short-term TKI use. We report the case of a 15-year-old girl with RAI-refractory metastatic PTC who achieved stable disease with long-term lenvatinib treatment for more than 5.5 years. Prospective, longitudinal studies of TKIs in RAI-refractory pediatric PTC are needed.

Phase 1 study of cabozantinib in combination with topotecan-cyclophosphamide for patients with relapsed Ewing sarcoma or osteosarcoma

PURPOSE

Phase 1 study assessing the safety and toxicity of cabozantinib in combination with topotecan and cyclophosphamide for relapsed osteosarcoma and Ewing sarcoma.

METHODS

Oral cabozantinib (25 mg/m2 ) was administered daily for 21 (dose level 1) or 14 (dose level -1B) days. Topotecan (0.75 mg/m2 ) and cyclophosphamide (250 mg/m2 ) were administered intravenously (IV) on days 1-5. A modified 3+3 design based upon first cycle dose-limiting toxicities (DLT) was used for dose escalation.

RESULTS

Twelve patients with a median age of 15 (12.9-33.2) years were enrolled (seven with Ewing sarcoma; five with osteosarcoma); all were evaluable for toxicity. At dose level 1, three of six patients developed first cycle DLT: grade 3 epistaxis, grade 3 transaminitis, and prolonged grade 2 thrombocytopenia. Six patients were enrolled on dose level -1B (interrupted cabozantinib, given days 8-21), with one first cycle DLT (grade 3 pneumothorax) observed. Of the 10 response evaluable patients, one had partial response (Ewing sarcoma), seven had stable disease, and two had progressive disease.

CONCLUSIONS

The recommended phase 2 doses and schedules for this combination are topotecan 0.75 mg/m2 IV days 1-5, cyclophosphamide 250 mg/m2 IV days 1-5, and cabozantinib 25 mg/m2 days 8-21. Non-concomitant administration of cabozantinib with cytotoxic therapy in this population has acceptable toxicity, while allowing for potential disease control.

A systematic review of recent phase-II trials in refractory or recurrent osteosarcoma: Can we inform future trial design?

BACKGROUND/OBJECTIVE

To analyze changes in recurrent/refractory osteosarcoma phase II trials over time to inform future trials in this population with poor prognosis.

METHODS

A systematic review of trials registered on trial registries between 01/01/2017-14/02/2022. Comparison of 98 trials identified between 2003 and 2016. Publication search/analysis for both periods, last update on 01/12/2022.

RESULTS

Between 2017 and 2022, 71 phase-II trials met our selection criteria (19 osteosarcoma-specific trials, 14 solid tumor trials with and 38 trials without an osteosarcoma-specific stratum). The trial number increased over time: 13.9 versus 7 trials/year (p = 0.06). Monotherapy remained the predominant treatment (62% vs. 62%, p = 1). Targeted therapies were increasingly evaluated (66% vs. 41%, P = 0.001). Heterogeneity persisted in the trial characteristics. The inclusion criteria were measurable disease (75%), evaluable disease (14%), and surgical remission (11%). 82% of the trials included pediatric or adolescent patients. Biomarker-driven trials accounted for 25% of the total trials. The survival endpoint use (rather than response) slightly increased (40% versus 31%), but the study H1/H0 hypotheses remained heterogeneous. Single-arm designs predominated over multiarm trials (n = 7). Available efficacy data on 1361 osteosarcoma patients in 58 trials remained disappointing, even though 21% of these trials were considered positive, predominantly those evaluating multi-targeted kinase inhibitors.

CONCLUSION

Despite observed changes in trial design and an increased number of trials investigating new therapies, high heterogeneity remained with respect to patient selection, study design, primary endpoints, and statistical hypotheses in recently registered phase II trials for osteosarcoma. Continued optimization of trial design informed by a deeper biological understanding should strengthen the development of new therapies.

Network pharmacology and experimental verification-based strategy for exploring the mechanisms of luteolin in the treatment of osteosarcoma

BACKGROUND

Luteolin is an active ingredient in various traditional Chinese medicines for the treatment of multiple tumors. However, the mechanisms of its inhibitory effect on osteosarcoma proliferation and metastasis remain unclear.

PURPOSE

To elucidate the anti-osteosarcoma mechanisms of luteolin based on network pharmacology and experimental verification.

STUDY DESIGN

Integrate network pharmacology predictions, scRNA-seq analysis, molecular docking, and experimental validation.

METHODS

Luteolin-related targets and osteosarcoma-associated targets were collected from several public databases. The luteolin against osteosarcoma targets were screened and a PPI network was constructed to identify the hub targets. The GO and KEGG enrichment of osteosarcoma-associated targets and luteolin against osteosarcoma targets were performed. And scRNA-seq analysis was performed to determine the distribution of the core target expression in OS tissues. Molecular docking, cell biological assays, and osteosarcoma orthotopic mouse model was performed to validate the inhibitory effect and mechanisms of luteolin on osteosarcoma proliferation and metastasis.

RESULTS

Network pharmacology showed that 251 luteolin against osteosarcoma targets and 8 hub targets including AKT1, ALB, CASP3, IL6, JUN, STAT3, TNF, and VEGFA, and the PI3K-AKT signaling pathway might play an important role in anti-osteosarcoma of luteolin. Analysis of public data revealed that AKT1, IL6, JUN, STAT3, TNF, and VEGFA expression in OS tissue was significantly higher than that in normal bones, and the diagnostic value of VEGFA for overall survival and metastasis was increased over time. scRNA-seq analysis revealed significantly higher expression of AKT1, STAT3, and VEGFA in MYC+ osteoblastic OS cells, especially in primary samples. Moreover, the docking activity between luteolin and the hub targets was excellent, as verified by molecular docking. Experimental results showed that luteolin could inhibit cell viability and significantly decrease the expression of AKT1, STAT3, IL6, TNF, and VEGFA, and luteolin could also inhibit osteosarcoma proliferation and metastasis in osteosarcoma orthotopic mouse model.

CONCLUSION

This study shows that luteolin may regulate multiple signaling pathways by targeting various genes like AKT1, STAT3, IL6, TNF, and VEGFA to inhibit osteosarcoma proliferation and metastasis.

Children's Oncology Group's 2023 blueprint for research: Bone tumors

The Children's Oncology Group (COG) Bone Tumor Committee is responsible for clinical trials and biological research on localized, metastatic, and recurrent osteosarcoma and Ewing sarcoma (EWS). Results of clinical trials in localized disease completed and published in the past 10 years have led to international standard-of-care chemotherapy for osteosarcoma and EWS. A recent focus on identifying disease subgroups has led to the identification of biological features associated with poor outcomes including the presence of circulating tumor DNA (ctDNA) at diagnosis, and specific genomic alterations-MYC amplification for osteosarcoma and STAG2 and TP53 mutation for EWS. Studies validating these potential biomarkers are under way. Clinical trials evaluating the addition of multitargeted kinase inhibitors, which are active in relapsed bone sarcomas, to standard chemotherapy are under way in osteosarcoma and planned in EWS. In addition, the Committee has data analyses and a clinical trial under way to evaluate approaches to local management of the primary tumor and metastatic sites. Given the rarity of bone sarcomas, we have prioritized international interactions and are in the process of forming an international data-sharing consortium to facilitate refinement of risk stratification and study of rare disease subtypes.

Measuring Safety and Outcomes for the Use of Compassionate and Off-Label Therapies for Children, Adolescents, and Young Adults With Cancer in the SACHA-France Study

Importance

Innovative anticancer therapies for children, adolescents, and young adults are regularly prescribed outside their marketing authorization or through compassionate use programs. However, no clinical data of these prescriptions is systematically collected.

Objectives

To measure the feasibility of the collection of clinical safety and efficacy data of compassionate and off-label innovative anticancer therapies, with adequate pharmacovigilance declaration to inform further use and development of these medicines.

Design, Setting, and Participants

This cohort study included patients treated at French pediatric oncology centers from March 2020 to June 2022. Eligible patients were aged 25 years or younger with pediatric malignant neoplasms (solid tumors, brain tumors, or hematological malignant neoplasms) or related conditions who received compassionate use or off-label innovative anticancer therapies. Follow up was conducted through August 10, 2022.

Exposures

All patients treated in a French Society of Pediatric Oncology (SFCE) center.

Main Outcomes and Measures

Collection of adverse drug reactions and anticancer activity attributable to the treatment.

Results

A total of 366 patients were included, with a median age of 11.1 years (range, 0.2-24.6 years); 203 of 351 patients (58%) in the final analysis were male. Fifty-five different drugs were prescribed, half of patients (179 of 351 [51%]) were prescribed these drugs within a compassionate use program, mainly as single agents (74%) and based on a molecular alteration (65%). Main therapies were MEK/BRAF inhibitors followed by multi-targeted tyrosine kinase inhibitors. In 34% of patients at least a grade 2 clinical and/or grade 3 laboratory adverse drug reaction was reported, leading to delayed therapy and permanent discontinuation of the innovative therapy in 13% and 5% of patients, respectively. Objective responses were reported in 57 of 230 patients (25%) with solid tumors, brain tumors, and lymphomas. Early identification of exceptional responses supported the development of specific clinical trials for this population.

Conclusions and Relevance

This cohort study of the SACHA-France (Secured Access to Innovative Medicines for Children with Cancer) suggested the feasibility of prospective multicenter clinical safety and activity data collection for compassionate and off-label new anticancer medicines. This study allowed adequate pharmacovigilance reporting and early identification of exceptional responses allowing further pediatric drug development within clinical trials; based on this experience, this study will be enlarged to the international level.

Cancer-associated fibroblasts: from basic science to anticancer therapy

Cancer-associated fibroblasts (CAFs), as a central component of the tumor microenvironment in primary and metastatic tumors, profoundly influence the behavior of cancer cells and are involved in cancer progression through extensive interactions with cancer cells and other stromal cells. Furthermore, the innate versatility and plasticity of CAFs allow their education by cancer cells, resulting in dynamic alterations in stromal fibroblast populations in a context-dependent manner, which highlights the importance of precise assessment of CAF phenotypical and functional heterogeneity. In this review, we summarize the proposed origins and heterogeneity of CAFs as well as the molecular mechanisms regulating the diversity of CAF subpopulations. We also discuss current strategies to selectively target tumor-promoting CAFs, providing insights and perspectives for future research and clinical studies involving stromal targeting.

Combination Early-Phase Trials of Anticancer Agents in Children and Adolescents

PURPOSE

There is an increasing need to evaluate innovative drugs for childhood cancer using combination strategies. Strong biological rationale and clinical experience suggest that multiple agents will be more efficacious than monotherapy for most diseases and may overcome resistance mechanisms and increase synergy. The process to evaluate these combination trials needs to maximize efficiency and should be agreed by all stakeholders.

METHODS

After a review of existing combination trial methodologies, regulatory requirements, and current results, a consensus among stakeholders was achieved.

RESULTS

Combinations of anticancer therapies should be developed on the basis of mechanism of action and robust preclinical evaluation, and may include data from adult clinical trials. The general principle for combination early-phase studies is that, when possible, clinical trials should be dose- and schedule-confirmatory rather than dose-exploratory, and every effort should be made to optimize doses early. Efficient early-phase combination trials should be seamless, including dose confirmation and randomized expansion. Dose evaluation designs for combinations depend on the extent of previous knowledge. If not previously evaluated, limited evaluation of monotherapy should be included in the same clinical trial as the combination. Randomized evaluation of a new agent plus standard therapy versus standard therapy is the most effective approach to isolate the effect and toxicity of the novel agent. Platform trials may be valuable in the evaluation of combination studies. Patient advocates and regulators should be engaged with investigators early in a proposed clinical development pathway and trial design must consider regulatory requirements.

CONCLUSION

An optimized, agreed approach to the design and evaluation of early-phase pediatric combination trials will accelerate drug development and benefit all stakeholders, most importantly children and adolescents with cancer.

A meta-analysis: the clinical value of PD-1 inhibitor or protein tyrosine kinase inhibitors in the treatment of advanced osteosarcoma

Backgrounds

PD-1 inhibitors and TKIs have been used to treat advanced osteosarcoma, but there is still a lack of intuitive data for the comparison of their efficacy. We conducted a meta-analysis to evaluate their therapeutic benefits.

Methods

A systematic methodological search of five primary electronic databases was performed. Studies with a randomized design of any type about PD-1 inhibitors or TKIs for the treatment of advanced osteosarcoma were included. The primary outcomes mainly included CBR, PFS, OS and ORR, The CR, PR, SD and AEs were the secondary outcomes. The survival period (months) of patients was taken as the main analysis data. Random-effects models were used for meta-analysis.

Results

Eight immunocheckpoint inhibitors in 327 patients from 10 clinical trials were finally evaluated. For OS, TKIs [11.67 months (95% CI, 9.32-14.01)] show more obvious advantages than PD-1 inhibitors [6.37 months (95% CI, 3.96-8.78)]. For PFS, TKIs [4.79 months (95% CI, 3.33-6.24)] are longer than PD-1 inhibitors [1.46 months (95% CI, 1.23-1.69)]. Although there was no fatal event, attention should still be paid, especially during the combined application of PD-1 inhibitors with TKIs since their obvious AEs.

Conclusions

The findings of this study suggest that patients with advanced osteosarcoma, TKIs may be more beneficial than PD-1 inhibitors. TKIs combined with PD-1 inhibitors has a bright future in the treatment of advanced osteosarcoma, but we should always pay attention to the strong side effects.

Safety profile of vascular endothelial growth factor receptor tyrosine-kinase inhibitors in pediatrics: a pharmacovigilance disproportionality analysis

Introduction: existing research on children consists primarily of phase I/II clinical trials for VEGFR-TKI. System reports of safety on the use of VEGFR-TKI in pediatrics are lacking. Aim: to investigate the safety profiles of VEGFR-TKI in pediatrics via the FDA Adverse Event Reporting System (FAERS). Method: data regarding VEGFR-TKIs were extracted from the FAERS between 2004Q1 to 2022Q3 and categorized by the Medical Dictionary for Regulatory Activities (MedDRA). Population characteristics were analyzed, and reporting odds ratio (ROR) was performed to identify risk signals associated with VEGFR-TKI. Results: 53,921 cases containing 561 children were identified in the database from 18 May 2005, to 30 September 2022. Among those in the system organ class, skin, subcutaneous tissue disorders, and blood and lymphatic system disorders in pediatrics contributed to over 140 cases. Palmar-plantar eythrodysesthesia syndrome (PPES) in VEGFR-TKI presented the most significant 340.9 (95% 229.2-507.0). And pneumothorax also gave a high reporting odds ratio of 48.9 (95% 34.7-68.9). For a specific drug, musculoskeletal pain gave a ROR of 78.5 (95% 24.4-252.6) in cabozantinib and oesophagitis in lenvatinib with a ROR of 95.2 (95% 29.5-306.9). Additionally, hypothyroidism presented a high signal, especially sunitinib, with a ROR of 107.8 (95% 37.6-308.7). Conclusion: the present study explored the safety profile of VEGFR-TKI in pediatrics using the FAERS database. Multiple skin and subcutaneous tissue disorders, as well as blood and lymphatic system disorders, were common VEGFR-TKI-related AEs in system organ class. No serious hepatobiliary AEs were detected. For the specific AEs, PPES and pneumothorax were VEGFR-TKI-related AEs that presented significantly higher signals than those in the general population.

Biological and clinical implications of FGFR aberrations in paediatric and young adult cancers

Rare but recurrent mutations in the fibroblast growth factor receptor (FGFR) pathways, most commonly in one of the four FGFR receptor tyrosine kinase genes, can potentially be targeted with broad-spectrum multi-kinase or FGFR selective inhibitors. The complete spectrum of these mutations in paediatric cancers is emerging as precision medicine programs perform comprehensive sequencing of individual tumours. Identification of patients most likely to benefit from FGFR inhibition currently rests on identifying activating FGFR mutations, gene fusions, or gene amplification events. However, the expanding use of transcriptome sequencing (RNAseq) has identified that many tumours overexpress FGFRs, in the absence of any genomic aberration. The challenge now presented is to determine when this indicates true FGFR oncogenic activity. Under-appreciated mechanisms of FGFR pathway activation, including alternate FGFR transcript expression and concomitant FGFR and FGF ligand expression, may mark those tumours where FGFR overexpression is indicative of a dependence on FGFR signalling. In this review, we provide a comprehensive and mechanistic overview of FGFR pathway aberrations and their functional consequences in paediatric cancer. We explore how FGFR over expression might be associated with true receptor activation. Further, we discuss the therapeutic implications of these aberrations in the paediatric setting and outline current and emerging therapeutic strategies to treat paediatric patients with FGFR-driven cancers.

The Use of Hydrogels for the Treatment of Bone Osteosarcoma via Localized Drug-Delivery and Tissue Regeneration: A Narrative Review

Osteosarcoma is a malignant tumor of bone that leads to poor mortality and morbidity. Management of this cancer through conventional methods involves invasive treatment options that place patients at an increased risk of adverse events. The use of hydrogels to target osteosarcoma has shown promising results both in vitro and in vivo to eradicate tumor cells while promoting bone regeneration. The loading of hydrogels with chemotherapeutic drugs provides a route for site-specific targeted therapy for osteosarcoma. Current studies demonstrate tumor regression in vivo and lysis of tumor cells in vitro when exposed to doped hydrogel scaffolds. Additionally, novel stimuli-responsive hydrogels are able to react with the tissue microenvironment to facilitate the controlled release of anti-tumor drugs and with biomechanical properties that can be modulated. This narrative review of the current literature discusses both in vitro and in vivo studies of different hydrogels, including stimuli-responsive, designed to treat bone osteosarcoma. Future applications to address patient treatment for this bone cancer are also discussed.

Drugging Hijacked Kinase Pathways in Pediatric Oncology: Opportunities and Current Scenario

Childhood cancer is considered rare, corresponding to ~3% of all malignant neoplasms in the human population. The World Health Organization (WHO) reports a universal occurrence of more than 15 cases per 100,000 inhabitants around the globe, and despite improvements in diagnosis, treatment and supportive care, one child dies of cancer every 3 min. Consequently, more efficient, selective and affordable therapeutics are still needed in order to improve outcomes and avoid long-term sequelae. Alterations in kinases' functionality is a trademark of cancer and the concept of exploiting them as drug targets has burgeoned in academia and in the pharmaceutical industry of the 21st century. Consequently, an increasing plethora of inhibitors has emerged. In the present study, the expression patterns of a selected group of kinases (including tyrosine receptors, members of the PI3K/AKT/mTOR and MAPK pathways, coordinators of cell cycle progression, and chromosome segregation) and their correlation with clinical outcomes in pediatric solid tumors were accessed through the R2: Genomics Analysis and Visualization Platform and by a thorough search of published literature. To further illustrate the importance of kinase dysregulation in the pathophysiology of pediatric cancer, we analyzed the vulnerability of different cancer cell lines against their inhibition through the Cancer Dependency Map portal, and performed a search for kinase-targeted compounds with approval and clinical applicability through the CanSAR knowledgebase. Finally, we provide a detailed literature review of a considerable set of small molecules that mitigate kinase activity under experimental testing and clinical trials for the treatment of pediatric tumors, while discuss critical challenges that must be overcome before translation into clinical options, including the absence of compounds designed specifically for childhood tumors which often show differential mutational burdens, intrinsic and acquired resistance, lack of selectivity and adverse effects on a growing organism.

Real-World Data on Cabozantinib in Advanced Osteosarcoma and Ewing Sarcoma Patients: A Study from the Hellenic Group of Sarcoma and Rare Cancers

Advanced osteosarcomas (OSs) and Ewing sarcomas (ESs) tend to have poor prognosis with limited therapeutic options beyond first-line therapy. Aberrant angiogenesis and MET signaling play an important role in preclinical models. The anti-angiogenic drug cabozantinib was tested in a phase 2 trial of advanced OS and ES and was associated with clinical benefits. We retrospectively analyzed the off-label use of cabozantinib in adult patients with advanced OS and ES/primitive neuroectodermal tumors (PNETs) in three centers of the Hellenic Group of Sarcoma and Rare Cancers (HGSRC). Between April 2019 and January 2022, 16 patients started taking 60 mg of cabozantinib for advanced bone sarcoma or PNET. Median age at cabozantinib initiation was 31 years (17-83). All patients had received peri-operative chemotherapy for primary sarcoma and between 0 and 4 lines of treatment (median; 2.5) for advanced disease. The most common adverse effects included fatigue, anorexia, hypertransaminasemia, weight loss, and diarrhea. One toxic death was noted (cerebral hemorrhage). Dose reduction to 40 mg was required in 31.3% of the patients. No objective response was noted, and 9/16 patients exhibited stable disease outcomes. Progression-free survival varied from 1 to 8 (median; 5) months. Our study demonstrates that cabozantinib has antitumor activity in this population. In the real-life setting, we observed similar adverse events as in the CABONE study and in other neoplasms.

Receptor Tyrosine Kinase Inhibitors for the Treatment of Recurrent and Unresectable Bone Sarcomas

Bone sarcomas are a heterogeneous group of rare tumors with a predominance in the young population. Few options of systemic treatment are available once they become unresectable and resistant to conventional chemotherapy. A better knowledge of the key role that tyrosine kinase receptors (VEGFR, RET, MET, AXL, PDGFR, KIT, FGFR, IGF-1R) may play in the pathogenesis of these tumors has led to the development of multi-target inhibitors (TKIs) that are progressively being incorporated into our therapeutic arsenal. Osteosarcoma (OS) is the most frequent primary bone tumor and several TKIs have demonstrated clinical benefit in phase II clinical trials (cabozantinib, regorafenib, apatinib, sorafenib, and lenvatinib). Although the development of TKIs for other primary bone tumors is less advanced, preclinical data and early trials have begun to show their potential benefit in advanced Ewing sarcoma (ES) and rarer bone tumors (chondrosarcoma, chordoma, giant cell tumor of bone, and undifferentiated pleomorphic sarcoma). Previous reviews have mainly provided information on TKIs for OS and ES. We aim to summarize the existing knowledge regarding the use of TKIs in all bone sarcomas including the most recent studies as well as the potential synergistic effects of their combination with other systemic therapies.

Current Status and Prospects of Targeted Therapy for Osteosarcoma

Osteosarcoma (OS) is a highly malignant tumor occurring in bone tissue with a high propensity to metastasize, and its underlying mechanisms remain largely elusive. The OS prognosis is poor, and improving the survival of OS patients remains a challenge. Current treatment methods such as surgical approaches, chemotherapeutic drugs, and immunotherapeutic drugs remain ineffective. As research progresses, targeted therapy is gradually becoming irreplaceable. In this review, several treatment modalities for osteosarcoma, such as surgery, chemotherapy, and immunotherapy, are briefly described, followed by a discussion of targeted therapy, the important targets, and new technologies for osteosarcoma treatment.

Systemic treatment for primary malignant sarcomas arising in craniofacial bones

Introduction

Craniofacial bones may be the site of origin of various sarcomas. We review the various malignancies affecting this region of the body and attempt to put systemic treatment approaches into perspective.

Material and methods

Non-systematic literature review

Results

Conventional types of osteosarcoma, Ewing sarcoma, and chondrosarcoma are the most frequent bone sarcomas occurring in craniofacial region, but variants may occur. The tumors’ biologies and the resulting treatment strategies vary distinctly. As a general rule, local control remains paramount regardless of histology. The efficacy of antineoplastic chemotherapy varies by type of malignancy. It is clearly indicated in Ewing sarcoma and related tumors, potentially of benefit in high-grade osteosarcoma, undifferentiated pleomorphic sarcoma, dedifferentiated and mesenchymal chondrosarcoma, and of no proven benefit in the others.

Conclusions

Various histologies demand various and distinct treatment approaches, with local control remaining paramount in all. The efficacy of systemic treatments varies by type of tumor. Prospective trials would help in all of these to better define systemic treatment strategies.

Origin and Therapies of Osteosarcoma

Simple Summary

Osteosarcoma is the most common malignant bone tumor in children, with a 5-year survival rate ranging from 70% to 20% depending on the aggressiveness of the disease. The current treatments have not evolved over the past four decades due in part to the genetic complexity of the disease and its heterogeneity. This review will summarize the current knowledge of OS origin, diagnosis and therapies.

Abstract

Osteosarcoma (OS) is the most frequent primary bone tumor, mainly affecting children and young adults. Despite therapeutic advances, the 5-year survival rate is 70% but drastically decreases to 20–30% for poor responders to therapies or for patients with metastasis. No real evolution of the survival rates has been observed for four decades, explained by poor knowledge of the origin, difficulties related to diagnosis and the lack of targeted therapies for this pediatric tumor. This review will describe a non-exhaustive overview of osteosarcoma disease from a clinical and biological point of view, describing the origin, diagnosis and therapies.

Paediatric Strategy Forum for medicinal product development of multi-targeted kinase inhibitors in bone sarcomas: ACCELERATE in collaboration with the European Medicines Agency with participation of the Food and Drug Administration

The eighth Paediatric Strategy Forum focused on multi-targeted kinase inhibitors (mTKIs) in osteosarcoma and Ewing sarcoma. The development of curative, innovative products in these tumours is a high priority and addresses unmet needs in children, adolescents and adults. Despite clinical and investigational use of mTKIs, efficacy in patients with bone tumours has not been definitively demonstrated. Randomised studies, currently being planned or in progress, in front-line and relapse settings will inform the further development of this class of product. It is crucial that these are rapidly initiated to generate robust data to support international collaborative efforts. The experience to date has generally indicated that the safety profile of mTKIs as monotherapy, and in combination with chemotherapy or other targeted therapy, is consistent with that of adults and that toxicity is manageable. Increasing understanding of relevant predictive biomarkers and tumour biology is absolutely critical to further develop this class of products. Biospecimen samples for correlative studies and biomarker development should be shared, and a joint academic-industry consortium created. This would result in an integrated collection of serial tumour tissues and a systematic retrospective and prospective analyses of these samples to ensure robust assessment of biologic effect of mTKIs. To support access for children to benefit from these novel therapies, clinical trials should be designed with sufficient scientific rationale to support regulatory and payer requirements. To achieve this, early dialogue between academia, industry, regulators, and patient advocates is essential. Evaluating feasibility of combination strategies and then undertaking a randomised trial in the same protocol accelerates drug development. Where possible, clinical trials and development should include children, adolescents, and adults less than 40 years. To respond to emerging science, in approximately 12 months, a multi-stakeholder group will meet and review available data to determine future directions and priorities.

The Cellular Tumor Immune Microenvironment of Childhood Solid Cancers: Informing More Effective Immunotherapies

Common pediatric solid cancers fail to respond to standard immuno-oncology agents relying on preexisting adaptive antitumor immune responses. The adoptive transfer of tumor-antigen specific T cells, such as CAR-gene modified T cells, is an attractive strategy, but its efficacy has been limited. Evidence is accumulating that local barriers in the tumor microenvironment prevent the infiltration of T cells and impede therapeutic immune responses. A thorough understanding of the components of the functional compartment of the tumor microenvironment and their interaction could inform effective combination therapies and novel engineered therapeutics, driving immunotherapy towards its full potential in pediatric patients. This review summarizes current knowledge on the cellular composition and significance of the tumor microenvironment in common extracranial solid cancers of childhood and adolescence, such as embryonal tumors and bone and soft tissue sarcomas, with a focus on myeloid cell populations that are often present in abundance in these tumors. Strategies to (co)target immunosuppressive myeloid cell populations with pharmacological anticancer agents and with selective antagonists are presented, as well as novel concepts aiming to employ myeloid cells to cooperate with antitumor T cell responses.

Lenvatinib dose, efficacy, and safety in the treatment of multiple malignancies

INTRODUCTION

Lenvatinib is an oral multitargeted tyrosine kinase inhibitor that has shown efficacy and manageable safety across multiple cancer types. The recommended starting doses for lenvatinib differ across cancer types and indications based on whether it is used as monotherapy or as combination therapy.

AREAS COVERED

This review covers clinical trials that established the dosing paradigm and efficacy of lenvatinib and defined its adverse-event profile as a monotherapy; or in combination with the mTOR inhibitor, everolimus; or the anti-PD-1 antibody, pembrolizumab; and/or chemotherapy.

EXPERT OPINION

Lenvatinib has been established as standard-of-care either as a monotherapy or in combination with other anticancer agents for the treatment of radioiodine-refractory differentiated thyroid carcinoma, hepatocellular carcinoma, renal cell carcinoma, and endometrial carcinoma, and is being investigated further across several other tumor types. The dosing and adverse-event management strategies for lenvatinib have been developed through extensive clinical trial experience. Collectively, the data provide the rationale to start lenvatinib at the recommended doses and then interrupt or dose reduce as necessary to achieve required dose intensity for maximized patient benefit. The adverse-event profile of lenvatinib is consistent with that of other tyrosine kinase inhibitors, and clinicians are encouraged to review and adopt relevant symptom-management strategies.

Challenges of Systemic Therapy Investigations for Bone Sarcomas

Bone sarcoma is a rare component of malignant solid tumors that accounts for only ~0.2% of malignancies. Bone sarcomas present various histological types, and genomic mutations differ markedly by the histological types. Although there are vast mutations in various bone sarcomas, most of them are non-actionable, and even potential targetable mutations that are actionable targets in other malignancies have not shown the appropriate responses in clinical trials for bone sarcomas. Investigations of new systemic therapy, including molecular targeted therapies for bone sarcomas, have thus not progressed like those for other solid tumors. Another problem is that high rates of pediatric/adolescent and young adult patients have bone sarcomas such as osteosarcoma, and patient recruitment for clinical trials (especially randomized trials) is challenging. For pediatric patients, evaluations of tolerability and appropriate dose modifications of new drugs are needed, as their findings could provide the threshold for investigating new drugs for bone sarcomas. To solve these problems, improvements in registry systems, real world data, and pediatric extrapolation have been attempted. We review the issues regarding targeted drug investigations for bone sarcomas, focusing on the current clinical evidence and efforts to resolve these issues.

Discovery of Potent and Orally Bioavailable Platelet-Derived Growth Factor Receptor (PDGFR) Inhibitors for the Treatment of Osteosarcoma

Platelet-derived growth factor receptors (PDGFRs) are now considered promising targets for the treatment of osteosarcoma. Herein, the design, synthesis, and structure-activity relationships (SAR) of novel pyrimidine-2,4-diamine derivatives that selectively inhibit PDGFRα/β kinases have been studied. The screening cascades revealed that 7m was the preferred compound among these derivatives, with IC₅₀ values of 2.4 and 0.9 nM for PDGFRα and PDGFRβ, respectively. Moreover, the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) experiment revealed that 7m has a substantial cytotoxic effect against all osteosarcoma cancer cell lines; 7m also displayed robust antitumor effects and low toxicity in a xenograft model. Additionally, 7m showed excellent bioavailability (F = 62.9%), suitable half-life (T_1/2 = 2.12 h), satisfactory metabolic stability, and weak CYP isoform inhibitory activity, suggesting that 7m is a potential drug candidate for PDGFR-driven osteosarcoma.

OLIE, ITCC-082: a Phase II trial of lenvatinib plus ifosfamide and etoposide in relapsed/refractory osteosarcoma

While survival rates for patients with relapsed/refractory osteosarcoma are low, kinase inhibitors have shown efficacy in its treatment. The multikinase inhibitor lenvatinib, plus ifosfamide and etoposide, showed antitumor activity in a Phase II study in patients with relapsed/refractory osteosarcoma. This Phase II randomized controlled trial (OLIE) will assess whether the combination of lenvatinib + ifosfamide + etoposide is superior to ifosfamide + etoposide alone in children, adolescents and young adults with relapsed/refractory osteosarcoma. The primary end point is progression-free survival; secondary and exploratory end points include, but are not limited to, overall survival, objective response rate, safety and tolerability, pharmacokinetic characterization of lenvatinib in the combination treatment, quality of life and quantification of baseline unresectable lesions that are converted to resectable.