Wu, Yue

Summary Outcomes for high‐risk paediatric classic Hodgkin lymphoma (cHL) improved with the addition of brentuximab vedotin (Bv) to doxorubicin, vincristine, etoposide, prednisone and cyclophosphamide (AVEPC) chemotherapy. We evaluated the prognostic implications of distant extra‐nodal sites contributing to stage IV disease. On AHOD1331 (NCT02166463), patients aged 2–21 years with high‐risk cHL (stage IIB with bulk/IIIB/IVA/IVB) were randomized to 5 cycles of doxorubicin, bleomycin, vincristine, etoposide, prednisone and cyclophosphamide (ABVE‐PC) versus Bv‐AVEPC. Patients with stage IV disease, determined by protocol‐defined and centrally reviewed Positron Emission Tomography ‐ Computed Tomography (PET‐CT), were identified. Baseline characteristics and progression‐free survival (PFS) were compared by pattern of stage IV involvement (lung, bone, bone marrow, multiple sites and others). A total of 340 patients (median age 15 years) with stage IV disease were included. Of these patients, 173 (51%) received ABVE‐PC and 167 (49%) Bv‐AVEPC. PFS was highest with lung‐only involvement (4‐year PFS 88.6%) and lowest with bone marrow‐only involvement (4‐year PFS 71.9%). Compared to ABVE‐PC, Bv‐AVEPC improved PFS among all stage IV patients (hazard ratio [HR] 0.53, 90% confidence interval (CI) 0.33–0.85) and in the lung‐only and bone‐only subgroups. However, no PFS benefit was observed in those with bone marrow‐only involvement. Among paediatric patients with stage IV cHL, Bv‐AVEPC improved PFS across most patterns of stage IV disease, except in those with bone marrow involvement. These results will guide efforts to improve outcomes among children with stage IV cHL.

Background: Chemotherapy in combination with radiotherapy (RT) is the standard for early-stage (ES) Hodgkin lymphoma (cHL). Despite high cure rates (12-year overall survival (OS) >93%), there is room to improve short and long-term outcomes for children and adults with ES cHL. Incorporation of immunotherapy (IO) into front line treatment of ES cHL is an opportunity to both improve progression-free survival (PFS) and maintain OS, while minimizing long-term morbidity and mortality by reducing exposure to RT and high-dose chemotherapy. Study Design and Methods: HL leaders of the NCTN groups, expert HL researchers and physicians, and representatives from the Cancer Therapy Evaluation Program (CTEP) formed a working group in April 2020 with the goals of harmonizing treatment approaches for ES cHL across pediatric and adult patients and reaching consensus regarding the optimal study design for incorporating IO therapy into frontline treatment. Study champions identified from each of the North American cooperative groups [Children's Oncology Group (COG), SWOG, ECOG-ACRIN, Alliance, NRG] and experts in imaging, radiation oncology, lymphoma biology and patient-reported outcomes (PROs) were included. The resulting COG-led clinical trial, AHOD2131, represents the largest ES cHL trial in the history of North American cooperative groups and the first to enroll patients across the age continuum. AHOD2131 (NCT05675410; Figure) is a randomized, phase 3 trial enrolling patients ages 5 to 60 years with newly diagnosed, previously untreated stage I and II cHL and will investigate the addition of the CD30-antibody drug conjugate brentuximab vedotin (Bv) with PD-1 blockade (nivolumab) compared to standard chemotherapy +/- RT. Since the April 2023 activation, 97 North American sites have activated the trial, and 21 participants have enrolled. Target enrollment is 1875 patients over 5 years of accrual, for an estimated 1782 eligible and evaluable patients. The primary objective is to compare the 3-year PFS of patients with ES cHL treated through a response-adapted, superiority design with either standard therapy or with an IO approach (BV + nivolumab). All patients will be stratified as favorable or unfavorable based on disease risk features at enrollment. Based on initial response assessment by PET/CT (via central review) after 2 cycles of ABVD, patients were classified to PET2 positive (SER, defined as 5 Point Score 4 or 5, ~15% of patients) and PET negative (RER). Those who are PET positive will receive involved site RT (ISRT). The SER and RER patients will be randomized to standard chemotherapy vs. IO therapy respectively. In addition to the primary outcome of PFS, there are 11 secondary and 10 exploratory aims. The secondary aims focus on OS, PFS of subgroups, and event-free survival at 12 years, physician-reported treatment-related adverse event (AE) rates, patient-reported AE using pediatric and adult versions of Patient-Reported Outcomes version of the Common Terminology Criteria for Adverse Events (PRO-CTCAE), and the capture of representation by self-report and the use of electronic PRO data collections. The exploratory aims include the assessment of imaging central review as compared to local institutional review and the use of convolutional neural networks through artificial-intelligence machine learning. The study will examine the effect of therapy on acute and long-term adverse effects including health-related quality of life (HRQoL) and OS for up to 12 years. The study will compare patient self-report and provider AE reports and evaluate the associations of self-reported race/ethnicity and social determinants of health (SDOH)and post-progression/post-relapse OS. AHOD2131 strengthens the effort between the North American cooperative groups to conduct collaborative clinical trials and aims to harmonize an improved standard of care for ES cHL across the age continuum.

SummaryThe Children's Oncology Group AHOD0831 study used a positron emission tomography (PET) response‐adapted approach in high‐risk Hodgkin lymphoma, whereby slow early responders (SERs) received more intensive therapy than rapid early responders (RERs). We explored if baseline PET‐based characteristics would improve risk stratification. Of 166 patients enrolled in the COG AHOD0831 study, 94 (57%) had baseline PET scans evaluable for quantitative analysis. For these patients, total body metabolic tumour volume (MTV), total lesion glycolysis (TLG), maximum standardized uptake value (SUVmax) and peak SUV (SUVpeak) were obtained. MTV/TLG thresholds were an SUV of 2.5 (MTV2.5/TLG2.5) and 40% of the tumour SUVmax (MTV40%/TLG40%). TLG2.5 was associated with event‐free survival (EFS) in the complete cohort (p = 0.04) and in RERs (p = 0.01), but not in SERs (p = 0.8). The Youden index cut‐off for TLG2.5 was 1841. Four‐year EFS was 92% for RER/TLG2.5 up to 1841, 60% for RER/TLG2.5 greater than 1841, 74% for SER/TLG2.5 up to 1841 and 79% for SER/TLG2.5 greater than 1841. Second EFS for RER/TLG2.5 up to 1841 was 100%. Thus, RERs with a low baseline TLG2.5 experienced excellent EFS with less intensive therapy, whereas RERs with a high baseline TLG2.5 experienced poor EFS. These findings suggest that patients with a high upfront tumour burden may benefit from intensified therapy, even if they achieve a RER.

Abstract Children’s Oncology Group (COG) trial AHOD0431 reduced systemic therapy and used response-adapted involved-field radiotherapy (IFRT) in early-stage pediatric classic Hodgkin lymphoma. We investigated the impact of positron emission tomographic response after 1 cycle (PET1) and on IFRT outcomes and pattern of relapse. Patients in AHOD0431 underwent PET1 response assessment after AVPC (doxorubicin, vincristine, prednisone, and cyclophosphamide). “Rapid early responders” (RERs) had a negative PET1 (PET1−); “slow early responders” (SERs) had a positive PET1 (PET1+). Patients with a partial response by computed tomographic and functional imaging after 3 chemotherapy cycles received 21-Gy IFRT, whereas complete responders had no IFRT. Progression-free survival (PFS) was evaluated for RERs and SERs treated with or without IFRT. Recurrence sites were initial, new, or both. Relapses involving initial sites were characterized as “within the PET1+ site” or “initially involved but outside the PET1+ site.” Median follow-up was 118 months. The 10-year PFS rate among RERs was 96.6% with IFRT and 84.1% without IFRT (P = .10), whereas SERs were 80.9% with IFRT and 64.0% without IFRT (P = .03). Among 90 RERs who did not receive IFRT, all 14 relapses included an initial site. Among 45 SERs receiving no IFRT, 14 of 16 relapses were in the initial site (9 PET1+ site only). Among 58 patients receiving IFRT, 5 of 10 relapses were in the PET1+ site. After 3 cycles of AVPC alone, RERs showed favorable results. Conversely, SERs had unfavorable outcomes with AVPC alone, although they improved with 21-Gy IFRT. RT remains an important component of treatment for SERs. This trial was registered at www.clinicaltrials.gov as #NCT00302003.

7504 Background: The anti-CD30 antibody drug conjugate, Brentuximab vedotin (Bv) is approved for adults with advanced stage HL but its use has not been established in children or adolescents. We compared the efficacy and safety of Bv with doxorubicin, vincristine, etoposide, prednisone and cyclophosphamide (Bv-AVE-PC) to the standard pediatric dose intensive regimen ABVE-PC, inclusive of bleomycin. Methods: This multicenter randomized, open-label phase 3 study enrolled patients 2-21 years (yrs) with previously untreated HL, stages IIB + bulk, IIIB, IVA, IVB. Patients were randomized to 5 cycles of either ABVE-PC or Bv-AVE-PC given every 21 days with granulocyte colony-stimulating factor support. Centrally reviewed PET-CT after 2 cycles (PET2) identified slow responding lesions (SRL) defined as Deauville score > 3. Involved site radiotherapy (ISRT) was given to bulky mediastinal adenopathy and SRL. The primary objective was 3-year EFS; events include relapse/progression, second malignant neoplasm (SMN) or death. Final data cutoff was 31 December 2021. Results: 600 participants were enrolled across 151 institutions from March 2015 to August 2019; 587 were eligible. Median age was 15.6 yrs (range 3.4-21). Patient and disease characteristics were balanced across study arms. Histology was nodular sclerosing in 76.5%. Stage distribution: 20.6% IIB-bulk; 19.3% IIIB; 28.5% IVA; 31.7% IVB. At a median follow-up of 42.1 mos (0.1-80.9), 3-year EFS (95%CI) by intent-to-treat analyses was 82.5% (77.4, 86.5) with ABVE-PC and 92.1% (88.4, 94.7) with Bv-AVE-PC (HR 0.41 (0.25, 0.67), p = 0.0002). Median time to 1st event was 9.4 months for both arms but the range differs by arm (3.6-57.8 ABVE-PC; 1.3, 25.8 Bv-AVE-PC). Relapse rate was 17% following ABVE-PC and 7% with Bv-AVE-PC. One SMN is noted in each arm: thyroid cancer at 57.8 mos and acute myeloid leukemia at 20.3 mos. 3-year overall survival (95%CI) was 98.5% (96.0, 99.4) for ABVE-PC and 99.3% (97.3, 99.8) for Bv-AVE-PC (p = 0.38). PET2 SRL rates were comparable (ABVE-PC 19% vs. Bv-AVE-PC 18%, p = 0.8). As-treated ISRT receipt did not differ (ABVE-PC 55.7% vs. Bv-AVE-PC 52.7%, p = 0.69). No difference in grade 3/4 adverse events was observed; myelosuppression, reflected in a 32% incidence of > grade 3 febrile neutropenia, did not differ by arm (p = 0.67). Only 19% of patients experienced > grade 2 neuropathy by the Balis pediatric neuropathy scale, with no difference between arms (p = 0.86). Conclusions: Brentuximab vedotin with AVE-PC in a dose intensive regimen has superior efficacy to ABVE-PC for pediatric patients with high-risk HL. A 59% risk reduction in EFS was achieved with no increase in toxicity and with fewer patients receiving ISRT compared to prior pediatric trials for high-risk HL. Clinical trial information: 02166463.