Parikh, Sameer A.

Introduction: Patients with chronic lymphocytic leukemia and small lymphocytic lymphoma (CLL/SLL) have a higher risk of developing other malignancies compared to the general population (Greene et al, J NCI 1978). Chemoimmunotherapy has previously been the mainstay of treatment and was associated with increased rates of other cancers (OC) (Thompson et al, Blood 2023). Targeted therapies such as Bruton tyrosine kinase inhibitors (BTKi) and BCL2 inhibitors were approved in the frontline setting in 2016 and 2019, respectively, and are now the standard of care for initial therapy (Shanafelt et al, NEJM 2019; Fischer et al, NEJM 2019). This study aims to compare the incidence of OC in patients with CLL/SLL treated with frontline therapies or managed with active surveillance. Methods: This is a retrospective case-control analysis of patients diagnosed with CLL/SLL during or after 2016 using the Department of US Veteran Affairs Central Cancer Registry (VACCR). Cases were patients with CLL/SLL diagnosed with incident OC, excluding nonmelanoma skin cancers. Frontline treatment with chemoimmunotherapy, monoclonal antibodies alone, or targeted therapies, such as BTKi or BCL2 inhibitor, was the exposure of interest compared to patients on active surveillance. Patients were followed until date of OC, death, or last follow up. Descriptive statistics were used to summarize continuous and categorical variables. Logistic regression was used to analyze the risk of developing OC while adjusting for potential confounders. Results: We identified 5244 patients with CLL/SLL who met inclusion criteria. Median follow up was 3.19 years (interquartile range [IQR] 1.61-5.14). The median age at diagnosis of CLL/SLL was 71.7 years (IQR 66.1-77.3) and most patients were white (78%) and male (97%). 3,460 (66%) patients were managed with active surveillance and 1,784 (34%) patients required frontline treatment: 1,318 (25%) targeted therapy, 329 (6%) chemoimmunotherapy, and 137 (3%) monoclonal antibodies alone. In patients treated with targeted therapies, patients were treated with ibrutinib (776, 59%), acalabrutinib (246, 19%), zanubrutinib (129, 10%), venetoclax (164, 12%), or combination of ibrutinib and venetoclax on a clinical trial (3, <1%). 505 (10%) patients were diagnosed with OC and 4739(90%) patients did not develop OC during the follow up period after diagnosis of CLL/SLL. Types of OC observed included neoplasms of the lung (120, 24%), prostate (105, 21%), gastrointestinal tract (72, 14%), hematologic malignancies (68, 13%), melanoma (45, 9%), kidney and bladder (43, 9%), head and neck (16, 3%), and other/unknown (36, 7%). More patients with OC had a history of tobacco use compared to those diagnosed with CLL/SLL without OC (70% vs 54%, p<0.0001). Fewer patients with OC had a history of alcohol use (60% vs 67%, p<0.0001). In a logistic regression analysis adjusted for age at diagnosis of CLL, race, and tobacco and alcohol use patients treated with chemoimmunotherapy had a higher risk of OC compared to those on observation (OR 2.4, 95% CI: 1.7-3.3, p<0.0001) whereas patients treated with targeted therapies or monoclonal antibodies alone did not have a higher risk of OC (OR 1.1, 95% CI 0.9-1.4 and OR 1.4, 95% CI 0.8-2.6, respectively) compared to the patients on active surveillance. A higher proportion of patients with OC were deceased compared to those without OC, 219/505 (43%) vs 1261/4739 (27%), respectively (p<0.0001) at cutoff date. Similar analyses of occurrence of OC in patients followed at tertiary centers including MD Anderson in Houston, Texas and Mayo Clinic in Rochester, Minnesota are ongoing and will be presented at the meeting. Conclusion: Initial treatment with targeted therapies or monoclonal antibodies alone was not associated with an increased risk of OC in US veterans diagnosed with CLL/SLL during and after 2016. However, initial treatment with chemoimmunotherapy was associated with a significant increase of OC compared to patients with CLL/SLL managed with active surveillance.

Introduction: Richter transformation is the development of an aggressive lymphoma, most commonly diffuse large B-cell lymphoma, in patients (pts) with chronic lymphocytic leukemia/small lymphocytic lymphoma (CLL/SLL). Transformation into Hodgkin lymphoma (HT) is a rare event and outcomes in pts with this complication in the current CLL/SLL therapeutic era of small molecule inhibitors (SMI; e.g., Bruton tyrosine kinase inhibitors [BTKi] and BCL2 inhibitors [BCL2i]) are unknown. Methods: We conducted a retrospective study of pts from 12 academic centers. Pts with HT who had not previously received chemotherapy for CLL/SLL-directed treatment (tx) were included. Pt, disease, and tx characteristics were collected. HT was categorized into 3 groups: “Concurrent HT,” defined as HT and CLL/SLL diagnosed simultaneously (within 3 months); “HT without prior CLL/SLL tx,” defined as HT and CLL/SLL diagnosed >3 months apart with the CLL/SLL never treated; and “HT with prior non-chemotherapy tx for CLL/SLL” defined as having received non-chemotherapy CLL/SLL-directed tx prior to the diagnosis (dx) of HT. Overall survival (OS) was measured from HT dx and estimated using the Kaplan-Meier method. Cox regression model was used to identify prognostic factors associated with OS. Results: Within a total cohort of 402 pts with Richter transformation (all histologies) without prior chemotherapy, 41 pts with HT (10%) were identified: 12 with concurrent HT, 10 with HT without prior CLL/SLL tx, and 19 with HT with prior non-chemotherapy tx for CLL/SLL. The median age at CLL/SLL dx was 62 years (range 31-96 years) and 73% were male. At CLL/SLL dx, 67% (14/21 evaluated) had unmutated IGHV, and 24% (8/34 evaluated) had TP53 disruption (del(17p) and/or TP53 mutation). The median age at HT dx was 65 years (range 31-96 years) among all pts. At HT dx, there was no significant difference in highest SUV on PET (median 12.3, range 3-31.1), lactate dehydrogenase (LDH) level (median 242 U/L, range 112-859 U/L), or lymph node longest diameter (median 4.6 cm, range 1.6-25 cm) among the 3 subgroups. The median time from CLL/SLL dx to HT dx was 5.4 years (range 0.3-16.5 years) in pts with HT without prior CLL/SLL tx and 4.2 years (range 0.5-17.3 years) in pts with HT with prior non-chemotherapy tx for CLL/SLL. The median number of prior non-chemotherapy CLL/SLL-directed tx was 1 (range 1-6) and included BTKi only (n=17) and BTKi and BCL2i sequentially (n=2); no patient had received only prior BCL2i. Among the 19 pts with HT with prior non-chemotherapy tx for CLL/SLL, 18 pts were on active tx at time of dx (17 BTKi, 1 BCL2i). Initial HT management included: doxorubicin, bleomycin, vinblastine, dacarbazine (ABVD; n=16), brentuximab vedotin (BV)-AVD (n=10), radiation only (n=2), other systemic tx (n=11), and supportive cares / hospice (n=2). All but 1 of the 11 other systemic tx were various HL tx regimens. Across all pts with available data (n=32), the overall response rate to 1st line HT tx was 78% (69% complete response rate); 13% had progressive disease and 9% (n=3; all with concurrent HT) died within 6 months without formal response assessment. A total of 11 pts received at least 1 additional line of therapy for HT, which included BV (n=4), an immune checkpoint inhibitor (n=1), or both (n=6) at any point beyond 1st line HT tx. Median follow-up from HT dx was 32.8 months (range 2.4-253.8 months). The 36-month OS for the entire cohort was 75% (95% CI: 55-87%). The 36-month OS estimates by subgroups were: 62% (95% CI: 26-84%) in pts with concurrent HT, 100% in pts with HT without prior CLL/SLL tx (no events by 36 months), and 67% (95% CI: 33-87%) in pts with HT with prior non-chemotherapy tx for CLL/SLL. Exploratory univariable analysis identified TP53 disruption at CLL dx (HR 12.36; 95% CI: 2.55-59.84) and lymph node longest diameter (HR 1.32 per 1 cm increase; 95% CI: 1.12-1.55) and LDH 2-fold increase (HR 3.97; 95% CI 1.24-12.68) at HT dx as prognostic for worse OS. HT subgroup was not prognostic. Conclusions: This is the largest report of outcomes in pts with CLL/SLL who develop HT following SMI tx without any prior chemotherapy, representing a contemporary cohort. Prior CLL/SLL tx status was not associated with OS; however, cautious interpretation is required given the sample size. Our findings support the use of appropriate HL-directed treatment in the setting of HT; however, OS estimates remain worse than would be expected in an older adult de novo HL cohort (Cheng Blood Adv 2022).

Background: Indolent non-Hodgkin lymphomas (iNHL) are incurable and disproportionately affect adults age >65 in whom frailty and functional impairment can impact disease management. The Vulnerable Elders Survey (VES-13) is a 13-item screening tool that incorporates age, self-rated health, physical function limitations, and functional disabilities to identify vulnerable older community-dwelling adults. Adults with a VES-13 score of >3 have a fourfold increased risk of death or functional decline over 2 years as compared to adults with a score <3 (Saliba et al, JAGS 2001). Our team previously showed that VES-13 >3 was associated with a higher risk of 1-year mortality in NHL (OR 3.26, 95% CI 2.15-4.96, Fama et al, ASH 2019), including in adults age <65. In this study, we determined whether VES-13 scores >3 were associated with quality of life (QOL) changes in adults with iNHL across the age spectrum. Methods: We used the Lymphoma Epidemiology of Outcomes (LEO) Cohort Study to identify adults enrolled from 2015-2020 with grade 1-3A follicular and marginal zone lymphoma (FL, MZL) who completed the VES-13 at enrollment and QOL surveys at enrollment and follow-up. The LEO Cohort Study enrolls participants within 6 months of diagnosis and collects information on disease status, QOL, health behaviors, and patient-reported functional assessment. For this analysis we included QOL measured using the Functional Assessment of Cancer Therapy-General (FACT-G) at years 1 and 2 post-enrollment. The FACT-G total score was the sum of 4 subscales (range): physical (PWB, 0-28), social/family (SFWB, 0-28), emotional (EWB, 0-24), and functional (FWB, 0-28) well-being. A higher FACT-G total score (range 0-108) indicated better overall QOL. VES-13 scores ranged from 0 (lowest risk for death or decline) to 10+ (highest risk). Generalized linear mixed models evaluated changes in QOL from baseline based on VES-13 score >3 (vulnerable) vs <3 (non-vulnerable), within groups by age at enrollment >65 and <65. Results: Our study included 1,186 participants: 42% age >65, 54% female, 84% non-Hispanic White, 10% Hispanic, 3.3% Black, and 1.4% Asian/Pacific Islander. Most (68%) were diagnosed with FL. FLIPI was high risk for 20%, and MALT-IPI was high risk for 23%. In the VES-13 <3 group, the mean (SD) baseline FACT-G total score was 86.5 (12.0), PWB 21.0 (3.5), SFWB 24.3 (4.3), EWB 18.8 (3.7), and FWB 22.3 (4.9). In the VES-13 >3 group, the mean (SD) baseline FACT-G total score was 70.4 (16.5), PWB 15.4 (5.6), SFWB 22.3 (5.5), EWB 17.5 (4.5), and FWB 15.3 (6.4); all significantly lower than the VES-13 >3 group (all p<0.01). In adults <65, 63 (9%) had a VES-13 >3, which was associated with a significant improvement from baseline in PWB at years 1 and 2 when compared to VES-13 <3 (changes in baseline PWB were 2.1, 2.9 for VES-13 >3 vs 0.2, 0.1 for VES-13 <3, all p<0.05). Similarly, we observed improvement in FWB from baseline at years 1 and 2 in the VES-13 >3 vs <3 group (2.4, 2.9 vs 0.4, -0.1, respectively all p<0.05). The VES-13 >3 group had a decline in their EWB at 1 year vs the VES <3 group (-0.5 vs 1.2, respectively, p=0.003). At year 2, total FACT-G improved from baseline in the VES-13 >3 group (5.6 for VES-13 >3 vs -0.5 for VES-13 <3, p=0.002). SFWB changes from baseline did not differ between groups. In adults >65, 83 (17%) had a VES-13 >3, which was associated with a significant improvement from baseline PWB (1.3, 1.5 for VES-13 >3 vs. 0.1, -0.1 for VES-13 <3), FWB (3.3, 2.2 for VES-13 >3 vs. 0.5, 0.1 for VES-13 <3), and total FACT-G score (5.2, 3.4 for VES-13 >3 vs. 1.0, -0.4 for VES-13 <3) when compared to VES-13 <3 at years 1 and 2 (all p<0.05). SFWB and EWB changes from baseline did not differ between groups. While there was improvement from baseline PWB and FWB in the VES-13 >3 group, QOL scores across all subscales remained below the VES-13 <3 group in the study period for both age groups. Statistical significance was maintained in models adjusted for baseline characteristics, including initial treatment strategy (observation, systemic, vs local) for both age groups. Conclusion: Although the vulnerable group reported worse QOL throughout the study period compared to the non-vulnerable group, survivors in the vulnerable group saw greater improvement in their physical and functional well-being at 1- and 2-years post-diagnosis. Additional analyses are underway to identify drivers of improvement in physical and functional well-being in vulnerable adults diagnosed with iNHL.

In 2023, Mayo Clinic in Rochester, MN, cared for over 20,000 patients with hematologic malignancies, roughly 42% of whom were rural. Patients residing in rural areas can face challenges in access to care, financial and time burdens due to treatment-related travel, and limited opportunities to participate in clinical trials. In 2021, The Leukemia & Lymphoma Society launched its IMPACT (Influential Medicine Providing Access to Clinical Trials) grant with Mayo Clinic being among its first recipients. The program provides funding to major cancer centers, in partnership with local community oncology centers, to help increase participation of patients traditionally underrepresented in clinical trials, including those who are rural, minority and/or economically disadvantaged. The award allowed significant changes to be made to clinical trial selection and facilitation models increasing access to trials within the rural setting and reducing the socioeconomic barriers noted above. This program included Rochester (IMPACT Hub) and Mayo Clinic Health System (MCHS) sites in Albert Lea, MN (65 miles to Hub), Eau Claire, WI (96 miles to hub), La Crosse, WI (73 miles to Hub), and Mankato, MN (84 miles to Hub). Methods: Two models were deployed; the full activation model where clinical trials were fully opened at MCHS sites, and the hybrid model where clinical trial participants are consented at the Hub and portions of participant care are conducted at MCHS sites. Initial barriers included limitations in clinical trials support staff, insufficient specimen processing equipment, medication storage and shipping limitations, MCHS catchment population unalignment with the Hub trials portfolio, and reduced bandwidth of providers due to patient care responsibilities. To address barriers to trial conduct, community center site champions were identified to streamline trial review and increase collaboration to better define site catchment areas, trial constraints, and site needs. A feasibility specialist was hired to support the program in trial design/implementation, barrier tracking, and to serve as a liaison between community site providers, study staff, and the program. Results: Since 2021, 20 clinical studies including 14 interventional treatment trials have been activated demonstrating 108 total patients accrued with 42 interventional accruals; 5 within the full activation model (13 accruals) and 15 in the hybrid model (29 accruals). Patients showed an average of 216 miles, with an estimated mileage cost of $142/trip based on the 2023 IRS mileage rate of $0.655/mile to the hub location. Nine of those patients traveled over 260 miles, with an estimated mileage cost of $170/visit to access clinical trials. Under the hybrid model, 8 patients transitioned portions of their care to their home city resulting in reduction of an average of 155 miles/visit, and 7 patients were able to reduce their travel time an average of 216 miles/visit. By estimating at least 10 study visits, the travel burden was reduced by 2,160 miles (4320 driving hours) and $1,420 in driving costs alone for participants. Using participant averages the 108 patients would spend a total of $15,336 in travel costs for just the initial visit, but when factoring in the 10-visit estimate, travel reduction could result in a net savings of $153,360. Based on travel data, it is estimated 11 of these patients would have required overnight accommodation using an average of $149/night hotel stay, a savings of $1,490/patient is estimated for the lifecycle of trial participation or $16,390 for the 11-patient cohort requiring accommodation. These results do not include travel companion and time off work costs. Efforts have been made to further develop the full activation model and 5 clinical trials are in activation. Data gathered from the program is being used to design strategies to reduce the administrative burden of clinical trial participation for community providers and launch screening programs. Conclusion: The Mayo Clinic LLS IMPACT program has demonstrated success in addressing barriers to opening clinical trials in the community-center setting and reduced the travel burden and financial impact to clinical trial participation in a cohort of trial participants. Centralized hub support of study activation and conduct and decentralized care to support treatment of patients in proximity of their home can be extended to other hospital systems and settings.

Background: Monoclonal B-cell lymphocytosis (MBL) is a common premalignant condition that can be classified into chronic lymphocytic leukemia (CLL)-type (CD5, CD23, and CD20 co-expression), and non-CLL-type (CD5-negative) based on flow cytometry immunophenotypes. CLL-type MBL is relatively well characterized with increased risk of hematologic (especially lymphoid) malignancies, serious infections, and decreased response to vaccinations. However, the prevalence, genetic predispositions, and clinical consequences of non-CLL-type MBL remain to be fully elucidated. Herein, we report findings in non-CLL-type MBL in a large screening cohort. Methods: We screened 10,330 individuals (40 years or older with no prior history of hematologic cancers) for MBL with highly sensitive flow cytometry, in the Mayo Clinic Biobank, with patients recruited from primary care-based clinics. Individuals were genotyped by Regeneron Genetics. Logistic regression was used to estimate odds ratios (OR) and 95% confidence intervals (CI). Among those individuals residing in the 27 counties surrounding Rochester, Minnesota, we identified incident hematologic malignancies and melanomas using ICD codes and the Rochester Epidemiology Project, a population based medical records linkage system. All diagnoses were manually reviewed for confirmation. Cox regression was used to calculate hazard ratios (HR) and 95% CIs, adjusted for age and sex. Results: We identified 1,736 individuals with MBL and 8,341 individuals without MBL. Among those with MBL, 246 (14.2%) had non-CLL-type MBL as the major clone. The median age of non-CLL-type MBL was 77 years (range, 47-95). The prevalence of non-CLL-type MBL significantly increased with age, with 0.5% prevalence among those between 40 to 59 years of age, 2.3% prevalence among those between 60 and 79 years, and 7.8% prevalence in those 80 years of age or older. The prevalence of non-CLL-type MBL was significantly higher (P < .001) among males (3.1%) than females (2.0%). Using the genome-wide complex trait analysis tool, the heritability of non-CLL-type MBL was estimated to be ~26%, suggesting inherited genetics plays a role in etiology. To identify common inherited variants, we first evaluated the known CLL susceptibility variants, many of which also associated with CLL-type MBL. Among the 42 variants, none were statistically associated (all P > .05) with non-CLL-type MBL. We next conducted a genome-wide association study to identify novel variants, and the most significant variant resided in 10q26.3 (minor allele frequency [MAF]control = 0.7%, MAFMBL = 3.5%, OR = 6.4, 95% CI 3.6-11.3, P = 5.7 * 10-8). Among the 6,478 individuals (192 with non-CLL-type MBL and 6,286 without MBL) followed for incident hematologic malignancies, 36 developed lymphoid and 23 developed myeloid malignancies after a median of 4.2 years of follow up. Similar to CLL-type MBL, non-CLL-type MBL was associated with a 5.2-fold risk for lymphoid malignancies (95% CI 2.0-13.0, P < .001). Elevated but not significant risks were observed for myeloid malignancies (HR = 2.3, 95% CI 0.5-10.3, P = 0.27). The lymphoid malignancies developed by individuals with non-CLL-type MBL included diffuse large B-cell lymphoma, multiple myeloma, marginal zone lymphoma, and other low-grade lymphomas. We recently reported that individuals with CLL-type MBL are at higher risk for developing melanoma (HR = 1.9, 95% CI 1.3-2.8). Interestingly, non-CLL-type MBL had no evidence of an association with melanoma risk (HR = 0.4, 95% CI 0.1-1.8). We did not observe a significant difference in overall survival between individuals with non-CLL-type MBL vs those without MBL. Conclusions: In the largest screening cohort to date, we evaluated the etiology and clinical outcomes of non-CLL-type MBL, an understudied yet common condition that occurs in ~4 million adults in the United States. Non-CLL-type MBL is more common in men and older individuals, and evidence supports that inherited genetics plays an etiological role with 10q26.3 locus identified as a novel susceptibility locus. Individuals with non-CLL-type MBL had significantly increased risk of lymphoid malignancies, similar to CLL-type MBL, but, distinct from CLL-type MBL, no evidence of an increased risk of melanoma. Our study provides insights into the prevalence, genetic predispositions and clinical consequences of non-CLL-type MBL and how it differs from the classic CLL-type MBL.

Background: Immune dysfunction is a hallmark of chronic lymphocytic leukemia (CLL), and several studies suggest that hypogammaglobulinemia at the time of CLL diagnosis may predict shorter time to first therapy (TTFT; Parikh et al, 2015). However, it is unclear if hypogammaglobulinemia can predict TTFT independent of the CLL-International Prognostic Index (CLL-IPI) and the tumor mutational load (TML). We sought to determine if serum immunoglobulin (Ig) levels at diagnosis can independently predict outcomes in patients with CLL and its precursor, high-count monoclonal B-cell lymphocytosis (MBL). Methods: We used the Mayo Clinic CLL Database to identify newly diagnosed CLL/MBL consented within 2 years of diagnosis. Next generation sequencing (NGS) was performed using a 59 gene panel (SureSelect) to detect mutated CLL genes. Serum Ig levels were quantitated by radial immunodiffusion (Immunoplates). Serum Ig levels below the lower limit of normal were defined as hypogammaglobulinemia. We used Chi-squared or Fisher's exact tests to compare discrete variables and the Kruskal Wallis test for continuous variables. TTFT was calculated from date of diagnosis to date of first treatment or date last known to be untreated. We used Cox regression models to estimate hazard ratios (HRs) and 95% confidence intervals (CIs) for TTFT and overall survival (OS) associations. Results: We identified 895 newly diagnosed patients (588 CLL and 307 MBL) who had undergone NGS for recurrent somatic mutations and had serum Ig levels available at the time of diagnosis. The median absolute B-cell count was 6.7 x109/L; 613 (69%) were male, 375 (42%) had unmutated IGHV genes, and 81 (9%) had TP53 disruption. Based on CLL-IPI, 412 (46%) patients had low risk, 285 (32%) had intermediate risk, and 198 (22%) had high/very high risk. The most commonly mutated genes were NOTCH1 (14%), SF3B1 (11%), TP53 (10%), NFKBIE (8%), ATM (6%), and BIRC3 (6%). Based on the number of genes with high impact or hotspot mutations, we classified 40%, 29%, and 31% patients with TML scores of 0, 1, or 2+, respectively. At CLL/MBL diagnosis, the median serum IgG, IgA, and IgM was 891 mg/dL (111-2620), 121 mg/dL (1-1150), and 44 mg/dL (5-1320), respectively; 284 (32%) patients had low serum IgG, 128 (17%) had low serum IgA, and 322 (42%) had low serum IgM. Low serum IgA was associated with mutations in NOTCH1, SF3B1, ATM, BIRC3 and NFKBIE, low IgM was associated with SF3B1 and BIRC3 mutations (all comparisons, P < .05), and low IgG was associated with BIRC3 mutation (P = .05). The median follow-up for the cohort was 8.4 years. A total of 359 patients progressed requiring therapy (299 CLL and 60 MBL), and 265 patients died (177 CLL and 88 MBL). The TTFT was significantly shorter for patients with low serum IgG compared to normal serum IgG at diagnosis (median 4.4 vs 10.8 years) and similar findings were observed in individuals with low serum IgA (1.7 vs 10.8 years) and those with low serum IgM (4.6 vs 11.1 years). On univariable analysis, the following were associated with a shorter TTFT: low serum IgG (HR: 1.8, 95% CI 1.4-2.2), low serum IgA (HR: 3.5, 95% CI 2.7-4.4), low serum IgM (HR: 1.9, 95% CI 1.5-2.3), TML score of 1 (HR: 1.7, 95% CI 1.3-2.2), TML of 2+ (HR: 4.4, 95% CI 3.4-5.7), CLL-IPI intermediate risk (HR: 3.7, 95% CI 2.8-4.8), and CLL-IPI high/very high risk (HR: 7.6, 95% CI 5.8-10.1) (all comparisons, P < .0001). In multivariable analyses after adjusting for CLL-IPI and TML, low serum levels of IgG (HR: 1.8, 95% CI: 1.5-2.3), IgA (HR: 2.4, 95% CI: 1.8-3.0), and IgM (HR: 1.8, 95% CI: 1.5-2.3) were independently associated with a shorter TTFT (all comparisons, P < .0001). No significant differences in OS were detected between patients with low and normal serum IgG, IgM, and IgA on univariate analysis. Similar results for TTFT and OS were observed after adding clonal B-cell count to the Cox model. Conclusions: Our study shows that low serum Ig levels at the time of initial diagnosis is predictive of TTFT independently of the CLL-IPI and TML, which can further risk stratify individuals with newly diagnosed CLL/MBL. Additionally, low serum IgA, IgM, and IgG levels at diagnosis are significantly associated with specific somatic mutations in individuals with newly diagnosed CLL/MBL.

Chronic lymphocytic leukemia (CLL), one of the most common types of leukemia among adults in the US, is characterized by the accumulation of CD5+CD19+ monoclonal B cells. Current clinical treatment approaches for progressive CLL patients focus on novel agents targeting Bruton Tyrosine Kinase (BTK) and Bcl-2. Although clinical trials combining novel agent have shown significant efficacy with high overall response and, in some cases, achievement of high rates of undetectable measurable residual disease (MRD), CLL remains incurable with a majority of patients eventually experiencing relapse of their disease. Therefore, it remains of high interest to expand therapeutic options. Transcriptional chemical inducers of proximity (TCIPs) are small molecules designed and developed by Dr. Gerald R. Crabtree at Stanford University. TCIPs are a new class of anticancer drugs that recruit endogenous cancer drivers or a downstream transcription factor to the promoters of cell death genes and activate their expression, resulting in apoptosis of cancer cells. Current TCIPs are produced by covalently linking small molecules that bind B-cell lymphoma 6 (BCL6) to those that bind to transcriptional activators, such as Bromodomain-containing protein 4 (BRD4) or cyclin-dependent kinases 9 (CDK9). The Stanford team has demonstrated TCIPs generate remarkable killing in diffuse large B cell lymphoma (DLBCL) cell lines, including chemotherapy-resistant, TP53-mutant lines, with a half maximal effective concentration (EC50) of 1-10nM at 72hours (h) and exhibited cell-specific and tissue-specific effects (Gourisankar et al, 2023). We have initiated TCIPs cytotoxicity assessment in primary leukemic cells from untreated CLL patients. Testing two types of TCIPs with a flow cytometry-based apoptosis assay, we found time and dose-dependent drug-associated killing in primary CLL B cells collected from untreated CLL patients over a 24-72h interval. The IC50 for BRD4-BCL6 TCIP JWZ-7-133 at 72h was 560nM while CDK9-BCL6 TCIP BAK-04-232 at 72h was 10nM. After 24, 48, and 72h exposure of CLL B cells to TCIP JWZ-7-133, the IC50 was 1050, 820 and 560nM, respectively. We also found that TCIP JWZ-7-133 exhibited a similar ability to inhibit leukemic cell viability with an IC50 of 1070nM using a cell viability assay, compared to a flow cytometry-based cell death assay (24h IC50 1050nM). CDK9-BCL6 TCIPs are designed and produced by covalently linking BI-3812 (binding to BCL6) and SNS-032 (binding to CDK9) with a rigid linker. BI-3812 is a potent and efficacious BCL6 inhibitor, inhibiting the BTB domain of BCL6, and SNS-032 is a potent and selective inhibitor of CDK9. When CLL B cells were treated with only BI-3812 or SNS-032 or TCIP BAK-04-232 as single agents for 72h, we found that TCIP BAK-04-232 had superior and significant killing effects compared to the single agents, with an IC50 of 10nM. Specifically this killing activity was more than 10-fold compared to SNS-032 alone (IC50 over 100nM), and more than 1,000-fold compared to BI-3812 alone (IC50 over 10,000nM). There remains an urgent to identify new categories of potent drug, inhibitor, or small molecules to expand potential clinical treatment options for patients with CLL. The results presented here indicate that TCIPs targeting BCL6 and BRD4/CDK9 have a strong capacity to induce high levels of cell death in CLL B cells at nanomolar concentrations, and this remarkable killing effect may be due to its unique gain-of-function drug mechanism. TCIPs provide a completely new drug direction and strategy for the design of anticancer drugs: to rewire cancer drivers to activate apoptosis in cancer cells. This study is the first of a kind demonstration of TCIPs in robustly targeting CLL B cells. Further studies to fully validate the preclinical activity of TCIPs and investigate the molecular mechanism(s) for TCIP mediated killing of leukemic B cells will help to define the role of TCIPs as a novel therapeutic approach in CLL.

Introduction Venetoclax + rituximab resulted in a 2-year progression-free survival estimate of 85% in the mostly 2nd-line, post-chemotherapy setting of the MURANO clinical trial (Seymour NEJM 2018). Short remissions with venetoclax in patients (pts) with prior cBTKi treatment (tx) for CLL are reported. However, these cohorts have included heavily pre-treated pts. Here, we report outcomes with venetoclax-based regimens in a contemporary cohort with cBTKi-exposed CLL and no prior chemotherapy. Methods We conducted a retrospective study of pts who received venetoclax for relapsed CLL after prior cBTKi tx at Mayo Clinic and across 8 centers in France. Pts with any prior chemotherapy tx were excluded. Pts were grouped as cBTKi-resistant (CLL disease progression on cBTKi) and cBTKi-exposed (any prior cBTKi tx but without disease progression). Overall survival (OS) was analyzed as the time from initiation of venetoclax until date of death or last known to be alive. Time to next therapy or death (TTNTD) after venetoclax was defined as the time from venetoclax initiation until the earliest date of next tx or death. Cox proportional hazards regression models were used to estimate associations of factors with OS and TTNTD. Results A total of 85 pts received venetoclax, including: venetoclax monotherapy (n=13, 15%), venetoclax + rituximab (n=45, 53%), and venetoclax + obinutuzumab (n=27, 32%). Patient characteristics at the time of venetoclax start were as follows: median age 69 years (interquartile range [IQR] 62-77), 59 (69%) male, 45% (33/73 evaluated) with TP53 disruption (del(17p) or TP53 mutation), 82% (46/56 evaluated) with unmutated IGHV, and 41% (15/37 evaluated) with complex karyotype (CK; ≥3 clonal structural or numerical abnormalities on karyotype). The median prior lines of therapy was 1 (IQR 1, 2); 32 (38%) pts had received prior anti-CD20 monoclonal antibody and 8 (9%) pts had received 2 prior cBTKi. Prior cBTKi tx was stopped for a reason other than disease progression in 46 (54%) pts (cBTKi-exposed) and due to CLL progression in 39 (46%) pts (cBTKi-resistant). TP53 disruption, unmutated IGHV, and CK were more common in the cBTKi-resistant subgroup. Among pts with cBTKi-resistant CLL, 60% (12/20 evaluated) had a BTK and/or PLCG2 mutation. Median follow-up from start of venetoclax-based therapy was 20 months. The median TTNTD and OS for the entire cohort was 36 (95% CI 29-not evaluable [NE]) and 68 (95% CI 39-NE) months, respectively. Among the 46 pts with cBTKi-exposed CLL, the median duration of prior cBTKi tx was 6.7 months (IQR 1.8, 23.7). The median TTNTD and OS from venetoclax start were both 78 months in pts with cBTKi-exposed CLL. The 24-month TTNTD and OS estimates were 73% and 81%, respectively. Among the 39 pts with cBTKi-resistant CLL, the median duration of prior cBTKi tx was 42.3 months (IQR 23.4, 60.1). The median TTNTD from venetoclax start in pts with cBTKi-resistant CLL was 30 months. The 24-month TTNTD estimate was 65% in the cBTKi-resistant subgroup, 53% with venetoclax monotherapy (n=5), 62% with venetoclax + rituximab (n=30), and 100% venetoclax + obinutuzumab (n=4). The median OS from venetoclax initiation was 39 months overall in pts with cBTKi-resistant CLL. The 24-month OS estimate was 84% in the cBTKi-resistant subgroup overall, 53% with venetoclax monotherapy, 87% with venetoclax + rituximab, and 100% with venetoclax + obinutuzumab. On a univariate analysis in the whole cohort, only TP53 disruption was associated with shorter TTNTD (HR 2.23; 95% CI 1.02-4.87; P=0.04) and only older age was associated with shorter OS (HR 1.05; 95% CI 1.007-1.095, P=0.02). On a univariate analysis in the cBTKi-resistant subgroup, only TP53 disruption was associated with shorter TTNTD (HR 6.68; 95% CI 1.51-29.46; P=0.01) and OS (HR 7.95; 95% CI 1.02-61.97; P=0.04). Duration of prior cBTKi exposure (as a continuous variable) was not associated with survival outcomes in the cBTKi-resistant subgroup. Conclusions Pts with chemotherapy-naïve, cBTKi-treated CLL had worse than expected outcomes with venetoclax-based tx in a mostly 2nd-line tx cohort, particularly pts with cBTKi-resistant CLL. The frequency of high-risk disease features, shorter duration of disease control with their initial cBTKi tx, and small cohort size warrant caution in generalizing these results to all pts with cBTKi-resistant disease. Novel tx trial strategies in 1st- and 2nd-line settings remain a high priority for high-risk pts.

Background: Chronic lymphocytic leukemia (CLL) is one of the most common leukemias in the United States (US), with an estimated incidence of 20,700 cases in 2024. Population-based studies conducted in Olmsted County (OC), Minnesota, reported an increase in CLL incidence over a 55-year period (1935 through 1989), which was attributed to increased detection of early-stage cases in individuals over age 50. In an updated study from 2000 to 2010 in OC, we reported no further increase in the incidence of CLL using the 2008 International Workshop on CLL (IWCLL 2008) guidelines. Additionally, when we compared the 1996 National Cancer Institute Working Group (NCI-WG 96) criteria with the IWCLL 2008 guidelines incorporating the monoclonal B-cell lymphocytosis designation, we found that the use of the IWCLL 2008 guidelines reduced the overt CLL incidence, modified the distribution of Rai Stages at diagnosis, and shortened the median time to first treatment (TTFT). Over the last two decades, 5-year survival for CLL has increased due to new therapies and improved supportive care. Herein we provide updated data on the incidence, prevalence, and natural progression of CLL in OC and studied similar features in an expanded 6-county region around Mayo Clinic, Rochester. Methods: We utilized the Rochester Epidemiology Project (REP), a population-based medical records linkage system, to identify CLL cases from 2000 to 2020 using International Classification of Diseases codes. We included individuals residing in OC and the expanded 7-county region (REP-7, including OC), for which data became available starting in 2010. CLL cases were included if they met the IWCLL 2008 criteria. All CLL diagnoses were confirmed by manual review of medical records and data on CLL-related factors were collected, including treatment status, prior history of other cancers, and overall survival (OS). Age- and sex-specific incidence rates were derived from REP census data and adjusted to the 2020 US white population. OS analyses were conducted using the Kaplan-Meier method. TTFT was calculated with death as a competing risk. Cox regression was used to evaluate the effect of decade on TTFT and OS among patients in OC. Results: From 2010-2020, 242 patients were diagnosed with CLL in REP-7, and between 2000-2020, 174 patients were diagnosed in OC. Among the 242 CLL patients in REP-7, the median age at diagnosis was 71 years (range 30-96),158 (65%) were male, 236 (99%) were white, and 74 (31%) had a history of other cancer, with non-melanoma skin cancer being the most common. After age and sex adjustment to the 2020 US white population, the CLL incidence in REP-7 and OC from 2010 to 2020 was 7.8 and 8.1 per 100,000 individuals, respectively. In OC, the age- and sex-adjusted CLL incidence from 2000 to 2020 was 7.5 per 100,000 individuals, showing no significant trend changes over time. Among the 242 patients diagnosed with CLL in REP-7 between 2010 and 2020, 102 received treatment with a median TTFT of 9.8 years. In OC from 2000 to 2020, 79 out of 174 patients received treatment with a median TTFT of 9.4 years. When comparing across two decades in OC, the median TTFT was 12.8 years for the period from 2000 to 2009, decreasing to 5.9 years between 2010 and 2020, but was not significantly different after accounting for age and sex. The median OS for patients diagnosed with CLL in REP-7 from 2010 to 2020 was 11 years. The median OS for patients in OC between 2000 to 2020 was 12.6 years. When comparing across decades in OC, the median OS was 8.9 years for the period from 2000 to 2009, increasing to 13.6 years for those diagnosed between 2010 and 2020, but this trend was not significantly different after accounting for age and sex. Prevalence data for REP-7 and OC were analyzed as of 01/01/2020. Additionally, prevalence data for OC were available for 01/01/2010. In REP-7, the prevalence of CLL was 97 per 100,000 individuals on 01/01/2020. In OC, the CLL prevalence was 86 per 100,000 individuals on 01/01/2010, and 100 per 100,000 individuals on 01/01/2020. Conclusions: We observed no substantial increase in the incidence rates of CLL in REP-7 from 2010 to 2020, nor in the 20 years of available data from OC. However, the prevalence of CLL in OC increased by 16% from 2010 to 2020. Additionally, evidence indicated a longer OS among newly diagnosed CLL cases in OC compared to previous decades, suggesting a potential impact of improved therapeutic approaches on OS.

Introduction: Chronic lymphocytic leukemia (CLL) is characterized by the accumulation of malignant lymphocytes in the lymph nodes, spleen, blood, and bone marrow. Although current clinical treatment approaches targeting Bruton Tyrosine Kinase (BTK) and Bcl-2, either as monotherapy or in combination are highly effective with high overall response, complete responses, and achievement of undetectable measurable residual disease (MRD), most patients eventually experience disease relapse. In this study, we utilized our unique mesenchymal stromal cells (MSCs) system, which mimics the in vivo stromal environment in CLL, to explore the combination interaction effect of the first-in-class BTK inhibitor, ibrutinib, with novel tumor microenvironment (TME)-directed drugs in CLL. Methods: Since 1999, patients with CLL seen at Mayo Clinic in Rochester, MN have been offered participation in a longitudinal study of CLL B-cell Biology (CLL Tissue Bank). This Tissue Bank is seamlessly integrated into the Mayo Clinic CLL Database where the clinical characteristics of all patients are prospectively maintained. Using this resource, we identified previously untreated CLL patients (n=10) for our experiments. Individuals with high risk CLL (defined as those with both unmutated IGHV gene mutations and either del17p- or del11q- by FISH) (n=5) and with low risk CLL (defined as those with both mutated IGHV genes and no del17p- or del11q- by FISH) (n=5) were studied. Annexin-V/PI apoptotic cell death assays were employed to evaluate the effects of TME-directed drugs including everolimus (mTOR inhibitor), MI-2 (MALT1 inhibitor), ruxolitinib (JAK1/2 inhibitor), S63845 (MCL-1 inhibitor), and venetoclax (Bcl-2 inhibitor) either as single agent, or in combination with ibrutinib on CLL B cells in direct contact with MSCs. Dose response curves and IC50 levels were generated for single agent killing effect in CLL. The combination interaction effects were determined by Combination Index (CI) values generated by CalcuSyn software indicating synergistic (CI < 0.9), additive (CI between 0.9 - 1.1), or antagonistic (CI > 1.1) interactions. Among drug combinations with synergistic CI values, the following indicated different levels: below 0.1 very strong, 0.1 - 0.3 strong, 0.3 - 0.7 good, and 0.7 - 0.9 moderate synergism. Results: All tested drugs exhibited different IC50 levels in CLL cells co-cultured with MSCs: MI-2 IC50 of 3.5uM, ruxolitinib IC50 of 18.5uM, S63845 IC50 of 0.115uM, venetoclax IC50 of 0.006uM, and both everolimus and ibrutinib did not reach IC50 levels at maximum tested doses. Of interest we observed more killing in high versus low-risk cohort when treated with everolimus (19uM vs. undetectable), MI-2 (2.5 vs. 4uM) and S63845 (0.09 vs. 0.14uM) as single agents (IC50, high vs. low, respectively), while ruxolitinib and venetoclax showed no differences. Combination interaction effect results showed highly synergistic interactions for all patients (good to strong synergism) when ibrutinib was combined with S63845 or venetoclax, moderate to strong synergism for ibrutinib and everolimus, moderate synergism to additive levels for ibrutinib and MI-2, and moderate synergism to antagonism for ibrutinib and ruxolitinib. We also observed more synergism in the low-risk cohort when treated with ibrutinib and MI-2/ruxolitinib combinations, but no difference with ibrutinib and everolimus/S63845/venetoclax combinations between low and high-risk cohort. Conclusions: In summary, we evaluated the pre-clinical combination effects of ibrutinib when used together with other novel agents on CLL B cells in the presence of TME, where patients were assigned to low or high-risk cohorts. Our study showed that ibrutinib exhibits highly synergistic effects with venetoclax, S63845 and everolimus in both cohorts. The observed difference in effectiveness between high and low-risk cohorts when treated with ibrutinib plus MI-2 or ruxolitinib suggests these combinations would be beneficial for a subset of patients with high risk CLL. These preclinical data offer preliminary insights that support the evaluation of therapeutic combinations in patient with high-risk CLL: a population with significant unmet medical needs. Funding Statement: This study was funded and supported by Pharmacyclics LLC, an AbbVie company.