PF383 PROGNOSTIC TESTING AND TREATMENT APPROACHES BASED ON REAL‐WORLD CLINICAL EXPERIENCE FROM AN INTERIM ANALYSIS OF THE INFORMCLL REGISTRY OF PATIENTS WITH CHRONIC LYMPHOCYTIC LEUKEMIA

Abstract

Background:Given the availability of novel targeted agents and updated guidelines for treatment (tx) of chronic lymphocytic leukemia (CLL), molecular‐genetic testing should be universally performed to guide tx decisions for patients (pts) with CLL. InformCLL (NCT02582879) is a prospective, observational real‐world registry of pts with CLL (96% community, 4% academic) receiving various lines of tx across >180 US centers.Aims:To describe rates of prognostic testing, predictors of testing, and current tx patterns for pts with CLL based on data from Feb 2018 data cut of informCLL registry.Methods:Enrollment began in Oct 2015. Eligible pts were ≥18 years (y), started approved anti‐CLL tx within 30 days of enrollment, and provided consent. First tx at enrollment was classified into 5 groups: chemoimmunotherapy (CIT), chemotherapy (CT), immunotherapy (IT), ibrutinib (ibr), and other novel agents. For this interim analysis, FISH, TP53 mutational status, and IGHV mutational status testing rates were summarized as frequency counts and percentages. CLL tx stratified by high risk status was also examined. Logistic regression analysis was used to examine predictors of FISH testing.Results:At the time of analysis, 840 pts had enrolled (459 previously untreated [1L]; 381 relapsed/refractory [R/R]). The majority were male (64%) and Caucasian (92%); median (range) age was 70y (34–95). Among all pts (N = 840), FISH testing was performed more frequently (n = 262 [31%]) than testing for TP53 (n = 89 [11%]) or IGHV (n = 94 [11%]). Among 459 1L pts, 164 (36%) had testing for FISH, 54 (12%) for TP53, and 55 (12%) for IGHV; among 381 R/R pts, 98 (26%) had testing for FISH, 35 (9%) for TP53, and 39 (10%) for IGHV (Figure). For all tested pts, 70/262 (27%) had 17p deletion [del(17p)] (1L, 47/164 [29%]; R/R, 23/98 [23%]), 23/89 (26%) had mutated TP53 (1L, 14/54 [26%]; R/R, 9/35 [26%]), and 69/94 (73%) had unmutated IGHV (U‐CLL; 1L, 35/55 [64%]; R/R, 34/39 [87%]). 13q deletion was the most common abnormality, reported in 60% of both 1L and R/R pts. Across all pts with del(17p) (n = 70), ibr was the most common tx (n = 38 [54%]; 1L, 27/47 [57%]; R/R, 11/23 [48%]), though 24 (34%) pts received CT/CIT (1L, 16/47 [34%]; R/R, 8/23 [35%]). Among all pts with mutated TP53 (n = 23), 15 (65%) received ibr (1L, 9/14 [64%]; R/R, 6/9 [67%]), and 7 (30%) CT/CIT (1L, 5/14 [36%]; R/R, 2/9 [22%]). Among all pts with U‐CLL (n = 69), 30 (43%) had ibr tx (1L, 13/35 [37%]; R/R, 17/34 [50%]) and 32 (46%) CT/CIT (1L, 20/35 [57%]; R/R, 12/34 [35%]). Based on stepwise multivariate logistic regression, shorter time from initial diagnosis to tx at enrollment and positive history of previous malignancy were significant predictors of FISH testing, regardless of line of tx.Summary/Conclusion:These findings suggest that prognostic testing patterns in real‐world settings have not improved despite the introduction of novel agents and specific testing guidelines (eg, iwCLL). Moreover, approximately one‐third of pts with del(17p), TP53 mutation, or U‐CLL still received CIT, which is known to have poor outcomes in these pts. Regression analysis suggests that the lack of testing is pervasive and not isolated to groups with specific access barriers. These real‐word emerging data from informCLL indicate that frequency of prognostic test remains suboptimal and underscore a need for education on utilizing these markers to guide CLL tx decisions and optimize clinical outcomes.image