Sher, Taimur

Background: To understand the changing trends in reporting of race and sex as a demographic variable in phase III lung cancer clinical trials published over the last 35 years. Methods: A total of 426 articles reporting results of phase 3 lung cancer clinical trials published from 1984 to 2019 were identified in PubMed. Statistical analysis on trends over time on percentage of minority and female participation were performed. Results: Only 137 (32.2%) of the 426 studies analyzed reported race of participants. Among those studies, we found that the mean participation rate of white participants was significantly higher (82.65%) (p < 0.001). We found a decrease in African American participants and an increase in Asian participants over time. When looking at sex, we found that although the rate of male participation (69.02%) was significantly higher than that of female participation (30.98%), the female participation has improved with time at a rate of 0.65% per year. Conclusions: We found that the reporting and participation of minority races continues to lag that of other demographic factors like sex in phase III clinical trials in lung cancer. Especially in African Americans, where the participation in lung cancer phase III clinical trials has declined despite the rising incidence in lung cancer.

Daratumumab is an anti-CD38 mAb, used frequently in combination with lenalidomide and pomalidomide. No studies compared daratumumab plus lenalidomide and dexamethasone (DRd) to daratumumab plus pomalidomide and dexamethasone (DPd) in lenalidomide-exposed multiple myeloma. We identified 504 consecutive multiple myeloma patients who received daratumumab at Mayo Clinic between January 2015 and April 2019. We excluded patients who received daratumumab in the first line, received more than four lines of therapy prior to daratumumab use, did not receive lenalidomide prior to daratumumab, or had an unknown status of lenalidomide exposure, and patients who received daratumumab combinations other than DRd or DPd. We examined the impact of using DRd compared to DPd on progression-free survival (PFS) and overall survival (OS) in patients with relapsed/refractory multiple myeloma. Out of 504 patients, 162 received DRd or DPd and were included; 67 were lenalidomide-exposed and 95 were lenalidomide-refractory. DRd was used in 76 (47%) and DPd in 86 (53%) patients. In lenalidomide-exposed multiple myeloma, there was no difference in median PFS; 34.2 months [95% confidence interval (CI), 22.8–44.6] for DRd compared to 25.2 months (95% CI, 4.9–35.3) for DPd, P = 0.2. In lenalidomide-refractory multiple myeloma, there was no difference in median PFS; 18.6 months (95% CI, 13–32) for DRd compared to 9 months (95% CI, 5.2–14.6) for DPd, P = 0.09. No difference in median OS was observed in DRd compared to DPd. Our study shows combining daratumumab with lenalidomide in patients with prior lenalidomide use is a viable and effective treatment option.

Bcl-2 and Mcl-1 proteins play a role in multiple myeloma (MM) cell survival, for which targeted inhibitors are being developed. AT-101 is an oral drug, which disrupts Bcl-2 and Mcl-1 function, impedes mitochondrial bioenergetic processes and induces apoptosis in MM cells. When combined with lenalidomide and dexamethasone (Rd), AT-101 significantly reduced tumor burden in an in vivo xenograft model of MM. These data provided rationale for a phase I/II study to establish the effective dose of AT-101 in combination with Rd (ARd regimen) in relapsed/refractory MM. A total of 10 patients were enrolled, most with high-risk cytogenetics (80%) and prior stem cell transplant (70%). Three patients were lenalidomide-refractory, 2 were bortezomib-refractory and 3 were daratumumab-refractory. The ARd combination was well tolerated with most common grade 3/4 adverse events being cytopenia’s. The overall response rate was 40% and clinical benefit rate was 90%. The median progression free survival was 14.9 months (95% CI 7.1-NE). Patients responsive to ARd showed a decrease in Bcl-2:Bim or Mcl-1:Noxa protein complexes, increased CD8+ T and NK cells and depletion of T and B-regulatory cells. The ARd regimen demonstrated an acceptable safety profile and promising efficacy in patients with relapsed/refractory MM prompting further investigation in additional patients.

Abstract Chronic Lymphocytic Leukemia (CLL) is considered a disease of antigen-naive CD5+CD23+CD19+κ/λ+ B-lymphocytes, in which the tumor microenvironment is highly immunosuppressive. Among several human B cell subsets, B10 [CD24hiCD27+CD38hi]/B regulatory cells (Bregs) are functionally discernable in patients with aggressive CLL as they support and regulate immunological tolerance via production of IL-10 and transforming growth factor β (TGF-β). In an ex vivo setting, we noted CD38hi CLL Bregs to promote transformation and expansion of CD4+CD25+FoxP3+Tregs; an effect that was abrogated in the presence of IL10/TGF-β neutralizing antibodies. In patients with CLL, Bregs also prohibit the expansion of cytotoxic T cells (CD8+T cells; Tc), natural killer (NK) cells and other pro-inflammatory lymphocytes (CD4+ helper T cells; Th1 and Th17). We noted that patients with CLL had a significantly higher % of Tregs (11.8±2.0) compared to healthy donors (1.9±0.3) and similar to Bregs, a substantial proportion of CLL Tregs had high CD38 expression (MFI=616.8±36.2). We demonstrated that an anti-CD38 therapeutic antibody was able to eliminate CD38+ Bregs and Tregs from CLL patients by immune effector mechanisms (ADCC, CDC, ADCP) as well as direct mitochondrial/FcγR-mediated apoptosis. Furthermore, in a PDX model of CLL, mice treated with anti-CD38 therapy had decreased % Bregs and Tregs but increased Th17 and CD8+ T-cells (vs. vehicle; p&lt;0.05). These observations carry implications beyond CLL for any Breg/Treg-dependent cancer or disease (i.e. Systemic Lupus Erythematosus, Rheumatoid arthritis, Sjögren’s syndrome), wherein CD38-targeted therapy could potentially rescue/improve an immune tolerant microenvironment by eradication of Bregs.

Abstract Hodgkin’s lymphoma (HL) is characterized by malignant CD30+ Reed-Sternberg (HRS) B-cells surrounded by an ineffective infiltrate of inflammatory immune cells. T-helper and T-regulatory cells presumably provide survival signals for HRS cells; rescuing them from immune-surveillance by CD8+ cytotoxic T lymphocytes and natural killer (NK) cells, which are also functionally anergic. Clinically, ≈10–30% of HL patients resulted in relapse after front line therapy; highlighting the need for development of new treatments. We investigated a novel bispecific CD16axCD30 antibody, AFM13 (Affimed Therapeutics, AG), which engages NK cells and recruits them towards CD30+ tumor cells. Safety of single-agent AFM13 has been demonstrated in a phase I clinical study, however, disease remission was observed in only 23% of patients. We hypothesized that combining AFM13 with another agent whose safety profile is already been established in HL and also activates NK cells (lenalidomide) could potentially increase anti-tumor efficacy of AFM13. We observed increased expression of CD107a, CD69, CD25 and IFNγ (activation markers) in NK cells isolated from HL patients (HL-NK), that were stimulated ex vivo with IL- 15 + lenalidomide. Pre-treatment with IL-2/IL-15 antibody has been shown to activate and restore T/NK cell cytolytic function. In line with this, IL-15+lenalidomide-stimulated HL-NK cells showed functional restoration by inducing specific lysis of human CD30+ lymphoma cells (30.55±1.49%) in a co-culture assay. While, AFM13 is being investigated in combination with anti-PD1 antibody therapy (NCT02665650), our preclinical data provides the rationale for an AFM13 + Len combination regimen for HL and potentially other CD30+ malignancies.