Grant, Barbara

7520 Background: With goal of simplifying clinical trials in lymphomas, we reported that bone marrow biopsies are irrelevant for response assessment in most patients (pts) with follicular lymphoma (FL) on trials (Rutherford JCO 2023). We then investigated impact of imaging frequency in FL clinical trials. We hypothesized that progression free survival (PFS) would not be different when imaging is performed less frequently than required by trials. Methods: We identified all trials through Alliance for Clinical Trials in Oncology that enrolled untreated pts with FL from 2008-2016. We considered 2 imaging schedules: protocol specified (control) vs relaxed (X) in which response assessments at every other required time point were omitted. For each trial, we estimated PFS using Kaplan Meier methods for the 2 schedules then determined difference in PFS between schedules as % change from control schedule in 2 year (yr) PFS rate. We performed simulation studies to approximate impact of less frequent imaging on PFS estimation using 50901 (low-intermediate risk FL) and 50904 (intermediate-high risk FL, control arm). We assumed exponential distribution for PFS, where rate parameter was calculated based on observed median PFS with uniform censoring distribution. Protocols for 50901 and 50904 mandated imaging every 4 months (mos) for 2 yrs then every 6 mos (S0). We ran 1000 iterations of 100 observations using 3 tumor assessment follow up schedules: every 6 mos for 2 yrs then yearly (S1), every 8 mos for 2 yrs then yearly (S2), or yearly (S3) for simulated progression times. We calculated deviation of PFS using simulated schedules from truth (S0). Results: Across 5 FL trials, median percent change of schedule X from control schedule in estimated 2yr PFS was 2.1% (0.0-30.8%) and in estimated 4yr PFS was 0.9% (-8.6-25.7%). Disparate result in 50901 is due to small shift in events with low number of pts at risk for progression. Simulation study results by trial were: for 50901, true median PFS 1.9 yrs and average median PFS for S1, S2, and S3 of 2.05, 2.11, and 2.21 yrs; for 50904 (control arm), true median PFS 4.1 yrs and average median PFS for S1, S2, and S3 of 4.16, 4.12, and 4.05 yrs. Conclusions: Our findings support decreased frequency of imaging studies in FL clinical trials, which would improve resource use and decrease pt burden. We plan a larger analysis to confirm results. https://acknowledgments.alliancefound.org . Clinical trial information: NCT00553501 , NCT01145495 , NCT01190449 , NCT01286272 , NCT01829568 .[Table: see text]

PURPOSE Bone marrow biopsies (BMB) are performed before/after therapy to confirm complete response (CR) in patients with lymphoma on clinical trials. We sought to establish whether BMB add value in assessing response or predict progression-free survival (PFS) or overall survival (OS) outcomes in follicular lymphoma (FL) subjects in a large, multicenter, multitrial cohort. METHODS Data were pooled from seven trials of 580 subjects with previously untreated FL through Alliance for Clinical Trials in Oncology (Alliance) and SWOG Cancer Research Network (SWOG) completing enrollment from 2008 to 2016. RESULTS Only 5/580 (0.9%) had positive baseline BMB, CR on imaging, and subsequent positive BMB ( P < .0001). Therefore, BMB were irrelevant to response in 99% of subjects. A sensitivity analysis of 385 FL subjects treated on an Eastern Cooperative Oncology Group study was included. In the Eastern Cooperative Oncology Group cohort, 5/385 (1.3%) had BMB that affected response assessment. Since some subjects do not undergo confirmatory BMB, we performed a landmark survival analysis from first radiologic CR with data from 580 subjects from Alliance and SWOG. Of subjects with CR on imaging (n = 187), PFS and OS were not significantly different among those with negative BMB to confirm CR (n = 47) versus those without repeat BMB (n = 140; PFS: adjusted hazard ratio, 1.10, 95% CI, 0.62 to 1.94, log-rank P = .686; OS: hazard ratio, 0.59, 95% CI, 0.23 to 1.53, log-rank P = .276). CONCLUSION We conclude that BMB add little value to response assessment in subjects with FL treated on clinical trials and we recommend eliminating BMB from clinical trial requirements. BMB should also be removed from diagnostic guidelines for FL except in scenarios in which it may change management including confirmation of limited stage and assessment of cytopenias. This would reduce cost, patient discomfort, resource utilization, and potentially remove a barrier to trial enrollment.

8038 Background: Bone marrow biopsies (BMB) are performed pre/post therapy to confirm complete response (CR) in patients (pts) with lymphoma on clinical trials. We evaluated 2 prior data sets and concluded that BMB impact response assessment in a minority of pts with follicular lymphoma (FL) (Rutherford BJH 2017; Rutherford ASH abstract 1605, 2018). We sought to establish if BMB add value in assessing response or identify distinct progression free (PFS) or overall survival (OS) outcomes in a large, multicenter, multi-trial cohort. Methods: Data were pooled from 7 trials of 580 pts with untreated FL conducted through the Alliance for Clinical Trials in Oncology and SWOG from 2002-2016. The proportion of pts with positive (+) baseline BMB, CR on imaging after treatment, and (+) repeat BMB was calculated using total pts enrolled as the denominator. We tested against the null hypothesis that the proportion was = 10%, the threshold below which BMB would be considered irrelevant for response assessment, versus (vs) the alternative hypothesis that this proportion was < 10%, using 1-sided exact binomial test. Response criteria were CT-based. Imaging was not used to assess BM involvement. Because confirmatory BMB were not completed in all indicated pts, landmark survival analyses compared PFS/OS of pts with CR on imaging and negative (-) BMB vs pts with CR on imaging without repeat BMB. Pts with CR on imaging were categorized as having (-) repeat BMB or no repeat BMB within 60 days of first CR on imaging. PFS and OS were calculated from time of first CR and estimated using Kaplan-Meier and Cox models adjusting for age, sex, stage, Follicular Lymphoma International Prognostic Index (FLIPI) score, and treatment type (targeted vs chemotherapy plus targeted therapy), and stratified by treatment arm. Results: Median age was 55 with 51% male, 96% stage III-IV, and 88% grade I-II. FLIPI scores were 113 low, 265 intermediate, and 199 high risk. 67% received chemotherapy-based regimens. Baseline BMB was (+) in 321 (55%). Only 5/580 (0.8%) had (+) baseline BMB, CR on imaging, and subsequent (+) BMB (p < 0.0001). Of pts with CR on imaging, PFS and OS were not different among pts with (-) BMB vs pts without repeat BMB (PFS: HR = 1.08, 95%CI 0.61-1.93, p = 0.783; OS: HR = 0.52, 95%CI 0.20-1.40, p = 0.199). Conclusions: BMB requirements may discourage pt participation in trials and add pain, expense and time without providing necessary information. We recommend eliminating BMB for response assessment from FL clinical trials. Clinical trial information: NCT00553501, NCT01145495, NCT01190449, NCT01286272, NCT01829568, NCT00822120, and NCT00770224 .