Real-world prognostic testing and treatment patterns in CLL/SLL: results from 1462 patients in the informCLL registry

The treatment landscape for chronic lymphocytic leukemia/small lymphocytic lymphoma (CLL/SLL) continues to evolve as new therapies are evaluated in clinical trials. With the availability of novel, targeted agents, questions remain regarding optimal treatment selection for patients with CLL/SLL in the real-world setting.1,2 Treatment guidelines for CLL/SLL have expanded in recent years with a greater understanding of the importance of prognostic biomarker testing to inform treatment mends interphase fluorescence in situ hybridization (FISH) testing to detect chromosomal abnormalities and sequencing for tumor protein p53 (TP53) mutations and for immunoglobulin heavy chain variable (IGHV) somatic hypermutation status,8 which are critical for risk stratification. Patients with high-risk genomic features are more likely to have poor outcomes when treated with chemoimmunotherapy (CIT) and should be considered for targeted therapies.8-10 Here, we present real-world prognostic testing rates, treatment selection, and treatment patterns over time in the fully enrolled population from the informCLL registry. Moreover, with the coronavirus disease 2019 (COVID-19) pandemic emerging during the course of this registry, we report COVID-19-related outcomes among these patients. The registry design has been previously reported,11 and additional methods of analyses are described (supplemental material). Of the 1462 eligible patients in the informCLL registry, 855 (58%) were previously untreated, and 607 (42%) had relapsed/refractory (R/R) disease. Community-based practices enrolled the majority of patients (93%). Table 1 lists the baseline demographics and clinical characteristics by LOT, and supplemental Tables 1 and 2 list these characteristics by initial treatment on the registry (index treatment). Median patient age was 71 years (range, 34-95), and most patients (88%) had an Eastern Cooperative Oncology Group performance status of 0 or 1. Consistent with previous interim analysis,11 FISH, TP53 mutation, and IGHV mutation testing were performed infrequently, occurring in less than one-third of all patients in the registry (Figure 1A). FISH testing was performed in 28% of patients (previously untreated: 33%, R/R: 22%), of whom 24% had del(17p) (previously untreated: 25%; R/R: 24%). TP53 mutation testing (11%) and IGHV mutation testing (12%) were performed in only a small fraction of patients. The large majority of patients who underwent TP53 or IGHV mutation testing also underwent other tests (supplemental Figure 1); among the patients with TP53 testing, 98% also had IGHV testing and/or FISH testing. Similarly, among those with IGHV testing, 91% also had TP53 testing and/or FISH testing. Rates of prognostic testing were similar regardless of age group (<70 years, >= 70 years) (supplemental Figure 2), insurance type (private, public, other, or none) (supplemental Figure 3), or geographic region (supplemental Figure 4), with higher rates generally seen