Ryan, Robert J.

Abstract Background: Glofit, a CD20/CD3 bispecific antibody, has shown efficacy in prospective trials, including the Phase III STARGLO study evaluating glofit plus gemcitabine/oxaliplatin (GemOx) in transplant-ineligible patients (pts) with R/R large B-cell lymphoma (BCL). However, concerns raised by the FDA's Oncology Drug Advisory Committee regarding the generalizability of the STARGLO data to U.S. pts underscore the need for real-world evidence. We report real-world outcomes of Glofit-GemOx in U.S. pts with R/R aggressive BCL. Methods: We conducted a multicenter retrospective review across 8 U.S. academic centers, identifying 31 pts with R/R aggressive BCL treated with Glofit-GemOx outside clinical trials. Baseline characteristics, treatment history, and outcomes were abstracted from medical records. Results: At Glofit-GemOx initiation: median age was 72 years (range, 34–88); 90% had stage III/IV disease. Histologic subtypes included DLBCL in 58% (n=18), high-grade BCL in 29% (n=9), PTLD/DLBCL in 6.5% (n=2), follicular lymphoma (FL) grade 3B in 3.2% (n=1), and Burkitt lymphoma (BL) in 3.2% (n=1). Germinal center B-cell phenotype was seen in 80% of evaluable cases. Double- (n=8) or triple-hit (n=1) cytogenetics were observed in 31% (n=9). Elevated LDH was present in 74%, and 16% had B symptoms. Median ECOG performance status was 1 (range, 0–3), and 23% (n=7) had received prior CAR T-cell therapy. Pre-treatment biopsy was performed in 77% (n=24) with CD20 expression tested in 74% (n=23). CD20 expression was negative in 3 pts by flow cytometry and/or immunohistochemistry. Pts received a median 1 prior line of therapy (range, 0-6); Glofit-GemOx was administered as 1L in 7% (n=2), and 2L in 58% (n=18). Median 4 cycles (range, 1-11); both 1L pts had prior FL (1 and 3 prior lines for FL). Twelve pts remain on therapy, 2 on Glofit monotherapy. Four pts were unevaluable (2 death pre-assessment; 2 pending evaluation). Among 27 evaluable pts, ORR was 78% (21/27) and CR rate was 41% (11/27). Among CD20- negative cases on pre- Glofit-GemOx biopsy (n=3), ORR was 33% (1/3), with 1 CR lasting 3.5 months. Of 11 pts who progressed on Glofit-GemOx, 6 were rebiopsied; 1 showed CD20 loss, 1 was previously CD20-negative. Among the 24 pts who received Glofit-GemOx as destination therapy, ORR of 75% (15/20 evaluable). Among pts with prior CAR T (n=7), the ORR and CR rate were both 43% (3/7). None received Glofit-GemOx within 30 days of CAR T-cell infusion; 4 received within 6 mo; 2 of whom achieved CR. Seven pts (24%) received Glofit-GemOx as bridging to CAR T. ORR pre-CAR T was 86% (6/7); 4 pt successfully proceeded to CAR T, 2 are pending infusion, and 1 progressed after 2 cycles and transitioned to alternate therapy. Three pts were evaluable post-CAR T with an ORR of 100% (3/3) and CR rate of 67% (2/3). At data cutoff, 23/31 pts were alive. Full PFS and OS data will be presented at ASH. Notable individual responses included a patient with relapsed BL post–DA-EPOCH-R who received Glofit-GemOx as 2L therapy and achieved a 6 mo CR without consolidation before progression. Another patient treated with Glofit-GemOx in the 7L setting after prior allogeneic transplant achieved a 3 mo CR prior to progression. CRS occurred in 58% (18/31), with grade ≥3 in 13% (4/31), including 2 possible treatment-related deaths. One occurred in a frail patient after the 1st dose, though neutropenic fever was present prior to Glofit administration. The second followed influenza A infection, respiratory failure, and possible grade 4 ICANS after the 2nd dose; attribution to CRS vs. infection was unclear. ICANS occurred in 10% (3/31), with one possible grade ≥3 case. Conclusions: This is the first U.S.-based real-world analysis of Glofit-GemOx, including more U.S. pts than the STARGLO trial, appear to demonstrate comparable response rates, potentially supporting its use as both bridging and destination therapy. Notable toxicities, including CRS, were observed, with 2 possible treatment-related deaths, with plausible alternate non-treatment related causes. Favorable responses were seen in bridging therapy and high-risk subgroups (transformed, HGBCL) which were excluded in the STARGLO trial. These findings support the real-world utility of Glofit-GemOx in the management of R/R aggressive BCL but underscore the need for caution due to associated toxicities. Further real-world and prospective evaluation are warranted, particularly in rare subgroups and as bridging therapy.

Abstract Radioimmunoassay of serum estrogen (sum of estrone and estradiol-17β) in 0.5 ml of human serum is described. After dilution of the serum, the estrogens are adsorbed on a Sephadex G-15 column in the presence of dilute HCl and then eluted with benzene. After evaporation of the benzene eluate, the estrogens are dissolved in bovine serum albumin (5 g/ liter solution, at pH 8.0). An aliquot of this solution is used for the assay. Serum estrogen concentrations (mean ± SD) were 69 ± 23 pg/ml in 105 normal men and 199 ± 146 pg/ml in 26 fertile women. In 109 postmenopausal women, estrogen was undetectable in seven sera, but in the remaining 102 it was 52 ± 30 pg/ml of serum.

AbstractPhosphatidylcholine acyltransferase (lecithin:cholesterol acyltransferase or LCAT; EC 2.3.1.43) activity was found to be present in pig ovarian follicular fluid (POFF), in addition to pig serum (PS). The cholesterol esterification rate in both POFF and PS is linear with incubation time up to 2 hr. The mean absolute rate of POFF‐cholesterol esterification was 8.1±0.4 nmoles per ml per hr approximately one‐fourth of that in PS. However, the fractional rate (percent of labeled cholesterol esterified per hr) of POFF‐cholesterol esterification was similar to that observed in PS. There was little variation of absolute rate of cholesterol esterification in the fluid obtained from different sizes of follicles. Fatty acid or triacylglycerol did not participate in the reaction of cholesterol esterification in POFF. No appreciable change in enzymatic activity was found from storing POFF at 4 C for periods of time up to 24 hr or at −70 C up to 2 months, but activity was lost thereafter. On the other hand, PS showed a much longer period of stability (5 days at 4 C and 9 months at −70 C). A discrepancy between the fatty acid composition of cholesteryl esters formed by the LCAT reaction and the fatty acid composition at the C‐2 position of phosphatidylcholine led us to propose a two‐step mechanism for the LCAT reaction. It is concluded that the LCAT of POFF, as well as that of plasma, is specific for individual fatty acids rather than for the fatty acid composition of phosphatidylcholine. The fatty acid concentration of lysophosphatidylcholine decreased during prolonged incubation times (6 to 21 hr) suggesting that the increased lysophosphatidylcholine formed as a product of the LCAT reaction may be reused as substrate for the LCAT reaction or for hydrolysis by lysophosphatidylcholine hydrolase.

Previously, using a synthetic peptide strategy, we determined that the region of the common glycoprotein hormone alpha subunit between residues 26 and 46 is a site of interaction of the hormone with the thyroid membrane-bound receptor for thyroid-stimulating hormone (TSH). We have undertaken to identify further the specific residues within this 21-amino acid span that are critical in hormone receptor binding. We synthesized three nested sets of peptide, two in which we systematically truncated the amino-terminal region of the sequence and another in which we truncated the carboxyl-terminal region, and we synthesized a fourth nested set in which we systematically substituted alanine for the native residues from the region of highest activity. Each peptide was tested in a TSH radioreceptor assay for its ability to inhibit binding of 125I-labeled bovine TSH to porcine thyroid membranes. Removal either by truncation or alanine substitution, of several specific residues resulted in a significant reduction in the ability of the sequence to interact with receptor; these residues included Cys31, Cys32, Phe33, Arg35, Arg42, Lys44, and Lys45, suggesting that they are crucial for binding activity. Loss of activity also occurred with substitution for Gly30 and Ser34, but the reduction was less pronounced. Amino-terminal truncation of the sequence through Arg35 (leaving the alpha-subunit peptide 36-46) resulted in greater than 98% loss of activity of the sequence. We conclude that two distinct receptor binding regions lie within the alpha-subunit 26-46 sequence. The first lies between residues Gly30 and Arg35 and includes Cys31, Cys32, and Phe33 as important constituents, and the second region lies between residues Arg42 and Lys45 and includes Lys44 as an important residue and Ser43 as a less important component.

Binding of human [ 125 I]luteinizing hormone to homogenates of luteinized rat ovaries is dependent upon time, temperature, and pH and is saturable. Injection of human chorionic gonadotropin in vivo or addition of unlabeled human chorionic gonadotropin or human or ovine luteinizing hormone in vitro inhibits binding, whereas follicle stimulating hormone or prolactin is without effect. The dissociation constant for binding of luteinizing hormone receptor is 0.79 nM. The number of binding sites is 94 femtomol/mg of wet weight. NaCl, KCl, MgSO 4 , and CaCl 2 at concentrations below 10 mM have no effect on binding, while all salts significantly inhibit binding at 150 mM. Binding of [ 125 I]luteinizing hormone to its receptors is destroyed by proteolytic enzymes and by phospholipase C and D. The total binding activity is quantitatively recovered in the 2000 × g pellet of the homogenate.