Bevacizumab, Irinotecan, or Topotecan Added to Temozolomide for Children With Relapsed and Refractory Neuroblastoma: Results of the ITCC-SIOPEN BEACON-Neuroblastoma Trial

PURPOSE

Outcomes for children with relapsed and refractory high-risk neuroblastoma (RR-HRNB) remain dismal. The BEACON Neuroblastoma trial (EudraCT 2012-000072-42) evaluated three backbone chemotherapy regimens and the addition of the antiangiogenic agent bevacizumab (B).

MATERIALS AND METHODS

Patients age 1-21 years with RR-HRNB with adequate organ function and performance status were randomly assigned in a 3 × 2 factorial design to temozolomide (T), irinotecan-temozolomide (IT), or topotecan-temozolomide (TTo) with or without B. The primary end point was best overall response (complete or partial) rate (ORR) during the first six courses, by RECIST or International Neuroblastoma Response Criteria for patients with measurable or evaluable disease, respectively. Safety, progression-free survival (PFS), and overall survival (OS) time were secondary end points.

RESULTS

One hundred sixty patients with RR-HRNB were included. For B random assignment (n = 160), the ORR was 26% (95% CI, 17 to 37) with B and 18% (95% CI, 10 to 28) without B (risk ratio [RR], 1.52 [95% CI, 0.83 to 2.77]; P = .17). Adjusted hazard ratio for PFS and OS were 0.89 (95% CI, 0.63 to 1.27) and 1.01 (95% CI, 0.70 to 1.45), respectively. For irinotecan ([I]; n = 121) and topotecan (n = 60) random assignments, RRs for ORR were 0.94 and 1.22, respectively. A potential interaction between I and B was identified. For patients in the bevacizumab-irinotecan-temozolomide (BIT) arm, the ORR was 23% (95% CI, 10 to 42), and the 1-year PFS estimate was 0.67 (95% CI, 0.47 to 0.80).

CONCLUSION

The addition of B met protocol-defined success criteria for ORR and appeared to improve PFS. Within this phase II trial, BIT showed signals of antitumor activity with acceptable tolerability. Future trials will confirm these results in the chemoimmunotherapy era.

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.

Phase I or II Study of Ribociclib in Combination With Topotecan-Temozolomide or Everolimus in Children With Advanced Malignancies: Arms A and B of the AcSé-ESMART Trial

PURPOSE

AcSé-ESMART is a proof-of-concept, phase I or II, platform trial, designed to explore targeted agents in a molecularly enriched cancer population. Arms A and B aimed to define the recommended phase II dose and activity of the CDK4/6 inhibitor ribociclib with topotecan and temozolomide (TOTEM) or everolimus, respectively, in children with recurrent or refractory malignancies.

PATIENTS AND METHODS

Ribociclib was administered orally once daily for 16 days after TOTEM for 5 days (arm A) or for 21 days with everolimus orally once daily continuously in a 28-day cycle (arm B). Dose escalation followed the continuous reassessment method, and activity assessment the Ensign design. Arms were enriched on the basis of molecular alterations in the cell cycle or PI3K/AKT/mTOR pathways.

RESULTS

Thirty-two patients were included, 14 in arm A and 18 in arm B, and 31 were treated. Fourteen patients had sarcomas (43.8%), and 13 brain tumors (40.6%). Main toxicities were leukopenia, neutropenia, and lymphopenia. The recommended phase II dose was ribociclib 260 mg/m2 once a day, temozolomide 100 mg/m2 once a day, and topotecan 0.5 mg/m2 once a day (arm A) and ribociclib 175 mg/m2 once a day and everolimus 2.5 mg/m2 once a day (arm B). Pharmacokinetic analyses confirmed the drug-drug interaction of ribociclib on everolimus exposure. Two patients (14.3%) had stable disease as best response in arm A, and seven (41.2%) in arm B, including one patient with T-acute lymphoblastic leukemia with significant blast count reduction. Alterations considered for enrichment were present in 25 patients (81%) and in eight of nine patients with stable disease; the leukemia exhibited CDKN2A/B and PTEN deficiency.

CONCLUSION

Ribociclib in combination with TOTEM or everolimus was well-tolerated. The observed activity signals initiated a follow-up study of the ribociclib-everolimus combination in a population enriched with molecular alterations within both pathways.

Treatment-Related Toxicities During Anti-GD2 Immunotherapy in High-Risk Neuroblastoma Patients

The introduction of immunotherapy using an anti-GD2 antibody (dinutuximab, ch14.18) has significantly improved survival rates for high-risk neuroblastoma patients. However, this improvement in survival is accompanied by a substantial immunotherapy-related toxicity burden. The primary objective of this study was to describe treatment-related toxicities during immunotherapy with dinutuximab, IL-2, GM-CSF, and isotretinoin. A retrospective, single center analysis of immunotherapy-related toxicities was performed in twenty-six consecutive high-risk neuroblastoma patients who received immunotherapy as maintenance therapy in the Princess Máxima Center (Utrecht, Netherlands). Toxicities were recorded and graded according to the CTCAE. Particular attention was drawn to pain and fever management and toxicities leading to dose modifications of dinutuximab and IL-2. Twenty-three patients (88%) completed all six courses of immunotherapy. Disease progression, isotretinoin-associated liver toxicity, and catheter-related infection in combination with peripheral neuropathy were reasons for immunotherapy discontinuation. The most common grade ≥3 toxicities for courses 1-5, respectively, were pain, catheter-related infections, and fever. In total, 310 grade ≥3 toxicities were recorded in 124 courses. Thirty-three grade 4 toxicities in 19/26 patients and no grade 5 toxicities (death) were seen. Fifty-nine percent of grade ≥3 toxicities were recorded in the two courses with IL-2. Catheter-related bloodstream infections were identified in 81% of patients. Four of these episodes led to intensive care admission followed by full recovery (grade 4).

Impact of COVID-19 in paediatric early-phase cancer clinical trials in Europe: A report from the Innovative Therapies for Children with Cancer (ITCC) consortium

INTRODUCTION

Data regarding real-world impact on cancer clinical research during COVID-19 are scarce. We analysed the impact of the COVID-19 pandemic on the conduct of paediatric cancer phase I-II trials in Europe through the experience of the Innovative Therapies for Children with Cancer (ITCC).

METHODS

A survey was sent to all ITCC-accredited early-phase clinical trial hospitals including questions about impact on staff activities, recruitment, patient care, supply of investigational products and legal aspects, between 1st March and 30th April 2020.

RESULTS

Thirty-one of 53 hospitals from 12 countries participated. Challenges reported included staff constraints (30% drop), reduction in planned monitoring activity (67% drop of site initiation visits and 64% of monitoring visits) and patient recruitment (61% drop compared with that in 2019). The percentage of phase I, phase II trials and molecular platforms closing to recruitment in at least one site was 48.5%, 61.3% and 64.3%, respectively. In addition, 26% of sites had restrictions on performing trial assessments because of local contingency plans. Almost half of the units suffered impact upon pending contracts. Most hospitals (65%) are planning on improving organisational and structural changes.

CONCLUSION

The study reveals a profound disruption of paediatric cancer early-phase clinical research due to the COVID-19 pandemic across Europe. Reported difficulties affected both patient care and monitoring activity. Efforts should be made to reallocate resources to avoid lost opportunities for patients and to allow the continued advancement of oncology research. Identified adaptations to clinical trial procedures may be integrated to increase preparedness of clinical research to futures crises.

The first report of pediatric patients with solid tumors treated with venetoclax

10524

Background: Dependence on the prosurvival protein B-cell lymphoma 2 (BCL-2) occurs in certain pediatric solid tumors, resulting in tumorigenesis and resistance to therapies. Venetoclax (VEN), an orally administered BCL-2-selective inhibitor, has preclinical anticancer activity in human-derived neuroblastoma models. Reported here are preliminary results from pediatric patients (pts) with recurrent or refractory (R/R) solid tumors treated with VEN monotherapy or VEN with cyclophosphamide and topotecan (Cy-Topo). Methods: This phase 1 open-label, 2-part study (NCT03236857) enrolled pts < 25 yr old with R/R malignancies; we report only on pts with solid tumors. Following a dose ramp-up, pts received 800 mg VEN (age/weight-adjusted adult equivalent) once daily for the first 8 wk; Cy-Topo was added optionally after wk 8. Dose-limiting toxicities (DLTs) were assessed during the first 21 days of VEN therapy or cycle 1 of VEN-Cy-Topo. Objectives included safety, toxicity, and preliminary efficacy. Results: As of Dec 17, 2019, 11 solid tumor pts were enrolled: neuroblastoma (n = 6), rhabdomyosarcoma (n = 2), Wilms’ tumor, Carney-Stratakis syndrome, and low-grade fibromyxoid sarcoma (n = 1 each). Median age was 11 yr (range 3–22); median time on study was 6.9 mo (range 1.2–17.8). All pts experienced ≥1 treatment-emergent adverse event (TEAE); vomiting (72%; all grades) was most common. Grade ≥3 TEAEs were reported in 82% of pts; febrile neutropenia (64%), decreased blood cell count, and neutropenia (36% each) were the most common. Seven pts received 800-mg monotherapy for 8 wk; 3 of these pts did not receive Cy-Topo after monotherapy. Of the 7 pts who received VEN-Cy-Topo, 3 pts received 400 mg VEN with Cy-Topo. DLTs of grade 4 neutropenia/thrombocytopenia with delayed count recovery occurred in 2 pts on 800 mg VEN-Cy-Topo, necessitating a dose de-escalation (to 400 mg VEN). Grade 4 neutropenia occurred in 2 pts on 400 mg VEN with Cy-Topo, leading to the addition of myeloid growth factor to the therapy regimen. The best response after 8 wk of VEN monotherapy was stable disease (SD). Six pts were evaluable for tumor response with VEN-Cy-Topo; 1 neuroblastoma pt had a complete response after 5 cycles of 400 mg VEN, 4 pts had SD (3 on 800 mg and 1 on 400 mg VEN) and 1 (800 mg VEN) had progressive disease as best response. Conclusions: Continuous dosing of VEN with Cy-Topo was not tolerated due to cytopenias in 4/7 pts with solid tumors. Discontinuous dosing of VEN with Cy-Topo is being explored. Clinical trial information: NCT03236857.

Randomized comparisons of bevacizumab (B) and irinotecan (I), added to temozolomide (T), in children with relapsed or refractory high-risk neuroblastoma (RR-HRNB): First survival results of the ITCC-SIOPEN BEACON-Neuroblastoma phase II trial

10501

Background: BEACON is a randomized phase 2 trial assessing whether inhibiting angiogenesis with bevacizumab adds to the activity of chemotherapy and evaluating chemotherapy regimens for children with RR-HRNB. Methods: Patients with RR-HRNB were eligible. There were randomizations (rand), in a 3x2 factorial design, to: T, IT or topotecan (To)-T, +/- B. Toxicity and response were reported in 2019 (ASCO, ESMO). Survival outcomes – progression-free (PFS) and overall (OS) – for the I and B rands are reported here (To rand is still open). The B rand used a relaxed alpha (1-sided p=0.2) for PFS as its phase 2 success criterion; the I rand was Bayesian. Cox model hazard ratios (HR) <1.0 indicate benefit for I or B. Heterogeneity tests (HT) assessed interactions between B and I. Analysis was intention-to-treat. Results: From 2013-19, 160 patients were randomized to B v. no B, including 121 to I v. no I, with: median age 5.8 years; 113 and 47 measurable and evaluable disease; 67 and 93 refractory and relapsed disease; 35 had MYCN amplification. Median follow-up was 15.4 months. PFS and OS are shown in the table. In the main comparisons (I v. no I, B v. no B), I improved PFS and OS (98% probability that true HR<1.0 for both) and B just met its success criterion (PFS: 1p=0.20; OS: 1p=0.19). However, there was some, but not conclusive, evidence of a positive interaction between B and I for both PFS (HT: p=0.06) and OS (HT: p=0.12). If real, this would suggest that adding either I (IT) or B (BT) to T does not improve outcome, but adding both (BIT) does. Twice as many patients had serious adverse events with BIT (57%) than with T (26%) or IT (27%), with BT at 40%. Conclusions: The BEACON results show that single agent T is suboptimal. Statistical uncertainty about an interaction between I and B means two further interpretations are possible: 1) IT and possibly BT are better than T; 2) IT and BT are not better than T, but I and B together (BIT) are better. Hence, a definitive conclusion on the best combination(s) to take forward is not currently possible and further randomized evaluation is needed. Clinical trial information: ISRCTN40708286. [Table: see text]