There have been significant advances in therapy for multiple myeloma (MM). The development of chimeric antigen receptor (CAR) engineered T cells have shown incredible responses by harnessing anti-tumor activity of T cells. However, most CAR-T therapies targeting BCMA involve long manufacturing and expansion times impacting its utility as well as outcome. In a phase 1 clinical trial (NCT04318327) of dose escalation study, we treated 55 RRMM patients, using the next-generation T-charge platform to generate anti-BCMA CAR-T cells in less than 2 days by reducing ex-vivo processing and enhancing in-vivo expansion and preserving T-cell stemness. As we reported earlier, the overall response rate was 98%, and the complete response rate was 55% (Sperling et al ASCO, 2023). Our earlier reports also showed that T-cell stemness is preserved, with CAR T cells expanding robustly in peripheral blood of patients with high clone diversity (Shuntaro et al ASH, 2024). To identify CAR related features that can predict for longer-term response, we performed the immune-monitoring study, evaluating the CAR-T cell-activation and functional activity in bone marrow (BM) microenvironment at 3 months following infusion of PHE885 using CyTOF analysis for 74 markers from 32 patients. We specifically evaluated the association of functional fitness of CAR-T cells in patients with sCR > 2 years (N=8, 27%) compared to patients who progressed (PD, N=24) within 2 years. We observed significant reduction in percentages of regulatory T cell population in CAR+ T cells in BM of sCR patients compared with PD patients (8% vs 18% respectively; p<0.05). We also observed significantly higher expressions of activation markers CD38 (69% vs 31%), CD28 (58% vs 32%) and CD27 (68% vs 48%) on CAR+ T cells in sCR patients compared to PD patients (p<0.05). Interestingly, we observed significantly higher expression of TIM-4 in CAR+ T cells in sCR patients (38% vs 8%; p<0.05), indicating that CAR-T cells in sCR patients have reduced apoptosis. Furthermore, sCR patients have significantly higher population of CAR+ T cells producing IL-2 (46% vs 16%) and granzyme-B (59% vs 28%) and higher frequency of IL-10-producing cells (43% vs 10%) compared with PD patients (p<0.05), suggesting higher proliferative and killing capacity as well as enhanced mitochondrial fitness. In summary, our results suggest that higher expression of activation markers and cytotoxic/proliferating cytokines in CAR-T cells is associated with sustained sCR of > 2 years. Interestingly, these CAR-T cells show less susceptibility to apoptosis and exhibit better mitochondrial fitness. Taken together, we conclude that these functional phenotypes of CAR-T cells in bone marrow might potentially be contributing to sustained outcomes following therapy.

T-ChargeTM is a novel platform for manufacturing CAR-T cells that reduces ex-vivo processing time to <2 days. A phase 1 clinical trial (NCT04318327) of durcabtagene autoleucel (PHE885) manufactured using the T-ChargeTM platform in relapsed/refractory multiple myeloma (R/RMM) has shown promising clinical activity. Previous correlative studies showed that T-ChargeTM manufacturing preserved T cell stemness in the CAR-T product and PHE885 expanded robustly with high TCR clonal diversity (Ikegawa et al., ASH 2023). CAR-T cells persisted for prolonged periods in some patients, allowing the detailed analysis of long-term persisting CAR-T cells. Among 32 patients with R/RMM treated at our center, we analyzed samples from 25 patients who had been followed for at least six months. At six months, CAR-T cells remained detectable in peripheral blood in 12 of 25 patients (median 38.3%; range, 2.1-70.8% of CD3+) by flow cytometry. CAR-T cells persisted for 12 months in 7 of 14 patients (median 15.6%; range, 1.04-75.9% of CD3+). At 24 months after CAR-T infusion, two of four patients continued to have detectable CAR-T by flow cytometry (61% and 0.8% of CD3+, respectively). CAR-T cells were predominantly CD4+ with effector memory phenotype at peak expansion, whereas the persisting CAR-T cells at later time points contained more less-differentiated T cells, including naïve and stem-like memory T cells. Mass cytometry revealed that the expression of activation, proliferation, and exhaustion markers on CAR-T cells declined after peak expansion. CAR-T TCR repertoire continued to be highly diverse 6-18 months after infusion and CAR-T cells present at later time points shared TCR clonotypes with those at peak expansion. Next, we evaluated the anti-BCMA function of post-infusion CAR-T cells in 12 patients who had persistent CAR-T cells in peripheral blood for >6 months. CAR-T cells were isolated by cell sorting from cryopreserved PBMC obtained during early expansion and at later time points (>3 months) and assayed their ability to directly kill reporter cells expressing BCMA. Isolated CAR-T cells continued to have anti-BMCA-specific cytotoxic activity that was not impaired at late time points. Notably, anti-BCMA-specific cytotoxicity in vitro was comparable in CAR T cells obtained from patients with ongoing clinical response and those with disease relapse. sBCMA levels at disease relapse were very low in 6 of 7 patients with CAR-T persistence. In contrast, sBCMA levels increased in 4 of 8 patients who relapsed after loss of CAR-T cells. These results indicate that T-chargeTM manufacturing produced CAR-T cells capable of long-term persistence with sustained anti-BCMA specific cytotoxic activity and BCMA loss likely contributes to relapse in these patients. We also explored various factors that could affect CAR-T persistence. The number of CAR-T cells at peak expansion and the number of Tscm/central memory T cells in the CAR-T product/leukapheresis were not associated with long-term CAR-T persistence. CD127 (IL-7Ra) expression on CAR-T cells was significantly higher in patients with long-term CAR-T persistence in CD4 T cells (day14; p = 0.04, day21; p = 0.01, and day28; p = 0.02) and CD8 T cells (day14; p = 0.04 and day21; p = 0.005), and this difference was not observed for non-CAR-T cells. Mass cytometry data confirmed that the CAR-T subset with high expression of CD127 at peak expansion was significantly increased in patients with long-term CAR-T persistence (p = 0.03). Because the T-chargeTM platform reduces ex-vivo CAR-T expansion, PHE885 expands predominantly in vivo. In conventional CAR-T manufacturing, common g-chain receptor cytokines, especially IL-7 and IL-15, promote ex-vivo expansion and long-term CAR-T persistence. Similarly, baseline cytokine levels may have an important role in the memory formation of post-infusion PHE885. Among common g-chain receptor cytokines, IL-7 levels at CAR-T infusion were significantly higher in patients with long-term CAR-T persistence (p = 0.03). In summary, BCMA CAR-T cells manufactured using the T-Charge process exhibit robust expansion in vivo and long-term polyclonal persistence for >6 months in 48% of patients. Long-term persisting CAR-T cells remain functionally active against BCMA expressing target cells in vivo and in vitro, and the IL-7/IL-7R pathway appears to have an important role in promoting long-term persistence of memory CD4+ CAR-T cells.

8004 Background: B cell maturation antigen (BCMA) targeted CAR-T cells are approved for RRMM. Long manufacturing time and high clinical demand limit access. T-Charge, an innovative platform that reduces manufacturing time to <2 days and preserves T cell stemness, results in robust expansion and prolonged CAR T cell persistence. Here we report updated results from the Phase I trial of T-Charge manufactured, fully human, BCMA CAR-T PHE885 (NCT04318327). Methods: Eligible pts had RRMM after ≥2 prior lines of therapy (tx). Pts received fludarabine and cyclophosphamide (or bendamustine) for lymphodepletion (LD) prior to PHE885 infusion. Primary objective was safety. Secondary objectives were clinical response and cellular kinetics. Results: As of December 22, 2022, 46 pts received PHE885 at the following doses: 2.5e6 (n=4), 5e6 (n=13), 10e6 (n=20), 14.3e6 (n=1), and 20e6 (n=8) CAR T cells. PHE885 was manufactured for 61% of pts at a single academic institution; these pts proceeded from apheresis to LD in a median of 16 days. Median age at enrollment was 65 y (range [R] 45-81), median prior lines of tx was 4 (R 2-10). 37% of pts had extramedullary disease; 96% were triple refractory. Despite aggressive disease, only 28% of pts required bridging chemotherapy, predominantly influenced by quick production time. 96% of pts experienced any gr cytokine release syndrome (CRS); 11% had gr 3 CRS. Median time to CRS onset was 8 (R 2-16) days and median duration was 4 (R 1-19) days. Immune effector cell-associated neurotoxicity syndrome (ICANS) occurred in 22% of pts; 7% had gr 3 ICANS. Dose limiting toxicities were experienced by 13% of pts and included gr 4 neutropenia, gr 4 lipase increase, gr 3 serum amylase increase, gr 3 neurotoxicity, gr 3 transaminitis, and gr 3 ejection fraction reduction. The most common tx-related gr ≥3 AEs included anemia (54%), neutropenia (50%), and thrombocytopenia (37%). Geo-mean peak PHE885 expansion (C max ) was 276,000 copies/µg by qPCR and 70.6% of CD3+ T cells by flow cytometry (n=41). The PHE885 transgene was detected in 13/14 (93%) pts at 6 mo and 5/7 (71%) at 12 mo post infusion. T cells with early memory phenotype were preserved in the final product and persisted in pts post infusion. In 43 efficacy-evaluable pts, the ORR was 98%. At 10e6 dose (n=19), ORR was 100% and CRR was 42% (median follow-up of 4.9 mo [R 1.4-11.8]); 60% of 10 evaluable pts were MRD negative at 10 -5 by NGS. Initial efficacy data at 20e6 and longer follow-up at active doses will also be presented. Conclusions: T-Charge manufactured PHE885 produced high response rates with no unexpected safety findings in heavily pretreated RRMM pts with aggressive disease. PHE885 expanded rapidly and showed durable persistence in vivo. Since conversion to CR/sCR has occurred as late as 18 months after infusion in this study, longer follow-up is ongoing to identify a recommended dose for future development. Clinical trial information: NCT04318327 .

BCMA targeted CAR-T cells are an effective therapy for patients with relapsed or refractory multiple myeloma (r/r MM). However, autologous CAR-T cell products are highly heterogeneous and the functional roles of various T cell populations within these products have not been established. Stem-like memory T cells (Tscm) are a rare T cell subset which maintain high capacity for self-renewal and multipotency. Previously, we demonstrated that the T-Charge TM platform, a novel rapid manufacturing process that reduces manufacturing time to <2 days, preserves less differentiated CAR-T cells which exhibit potent anti-tumor activity and robust expansion in preclinical models (Dexiu Bu, ASH 2021). We conducted a phase 1 clinical trial in r/r MM (NCT04318327) of durcabtagene autoleucel (PHE885), a fully human product manufactured using the T-Charge platform. Here we present a detailed analysis of CAR-T cell products and subsequent expansion of CAR-T cells in 32 patients enrolled in this clinical trial at the Dana-Farber Cancer Institute. Apheresis products (APH), final products (FP) and post-infusion peripheral blood mononuclear cells (PBMC) were characterized using flow cytometry, mass cytometry (CyTOF) and TCR sequencing. We previously reported a 98% overall response rate (ORR) across all dose levels (2.5-20x10 6 CAR-T cells) and 100% ORR at doses >5x10 6 cell dose (Sperling, ASCO 2023). CAR-T cells expanded rapidly after infusion reaching median peak levels of 3,118 cells/ul (range 373 to 17,865) with a median 87.4% (range, 46.9-97.8) of CD3+ T cells expressing the CAR at a median of 14 days (range 10 to 27) after infusion. CAR-T cells persisted at high levels with transgene detectable by qPCR in 67% of patients at 6 months. Among 28 evaluable patients, 13 (43%) had >20% CAR positive T cells detectable by flow cytometry at 3 months. Phenotypic analysis of APH and FP samples showed that less-differentiated T cell subsets, including Tscm and central memory T cells were maintained in FP. CyTOF evaluation of functional markers revealed high expression of proliferation and activation markers in Tscm in FP and subsequently in CAR-T cells at the time of peak expansion in vivo. Subsequently, more differentiated CAR-T cells increased, accompanied by a decline in activation markers, while no significant changes were observed in inhibitory receptors. The proportion of Tscm in the FP positively correlated with early in vivo CAR-T cell expansion. TCR repertoire diversity and TCR clone tracking were used to characterize product manufacturing and CAR-T cells in peripheral blood after infusion. We sorted naïve/Tscm CD4 T cells, naïve/Tscm CD8 T cells, memory CD4 T cells, and memory CD8 T cells from APH and FP, and isolated CAR-positive CD4 T cells, CAR-positive CD8 T cells, CAR-negative CD4 cells, and CAR-negative CD8 T cells from post-infusion PBMC by fluorescence-activated cell sorting and ran TCR sequence from the extracted gDNA from each T cell subpopulation. Measurement of TCR diversity post-infusion revealed higher TCR repertoire diversity in CAR-T cells than in non-CAR-T cells. Notably, post-infusion CAR-T cells shared significantly more TCR clonotypes with T SCM than with memory T cells in the FP, suggesting that the highly heterogeneous post-infusion CAR-T clones were preferentially derived from T SCM clones in the FP. In three evaluable patients with long-term persistence, a highly diverse TCR repertoire in CAR T cells was maintained 1 year after treatment. Our findings demonstrate that the T-Charge™ manufacturing platform successfully maintains highly heterogeneous transduced Tscm clones with self-renewal potential in durcabtagene autoleucel products. Maintenance of Tscm in manufactured products contributes to robust CAR-T expansion and long-term persistence of CAR-T cells with a highly diverse TCR repertoire after infusion.

Background: CD19-directed CAR-T cell therapies (tx) have shown efficacy in patients (pts) with B-cell malignancies. However, many pts fail to respond or experience disease relapse after initial response. YTB323 (rapcabtagene autoleucel) is an autologous CD19-directed CAR-T cell tx generated by the innovative T-Charge™ platform, which produces CAR-T cells by a rapid manufacturing process (2 days) preserving T-cell stemness. This methodology is expected to increase CAR-T cell persistence and expansion and yield higher efficacy and a manageable safety profile. Here we present efficacy and safety, dose exposure, and biomarker analyses for rapcabtagene autoleucel in adults with r/r DLBCL in the ongoing Phase I, multicenter, dose-escalation study (NCT03960840). Methods: Eligible pts had r/r DLBCL after ≥2 lines of prior tx, measurable disease at enrollment, and ECOG 0-1. Pts received single-dose rapcabtagene autoleucel at targeted dose level (DL) 1 (2.5×106 CAR+ cells), DL2 (12.5×106 CAR+ cells), DL3 (25×106 CAR+ cells), or DL4 (40×106 CAR+ cells). Primary endpoints characterized safety and dose-limiting toxicities to identify a recommended dose. Secondary endpoints include response rate by local investigator assessment and cellular kinetics. Results: As of March 31, 2022, 45 pts with r/r DLBCL received rapcabtagene autoleucel: 4 at DL1, 28 at DL2, 7 at DL3, and 6 at DL4. Median age was 64.8 y, 67% received 2 prior lines of tx, and 29% had prior autologous stem cell transplant. Median (range) time since most recent relapse/progression was 2.8 (1.4-81.8) mo. Pts were followed for a median (range) of 10 (0.3-29) mo. Complete response (CR) rate at DL2 was 65%. CR at DL2, excluding pts in CR before rapcabtagene autoleucel (due to either a late effect of prior tx or bridging chemotherapy), was 61%. Responses at DL2 were durable, with CR rates of 63% (12/19) at 3 mo and 69% (11/16) at 6 mo (Figure 1). Median duration of response at DL2 was not reached. Of 45 pts evaluable for safety, 96% reported 1 adverse event (AE) of any grade (Gr) and 89% had ≥1 AE Gr ≥3. Cytokine release syndrome (CRS) was experienced by 15 pts (33%): 1 at DL1, 10 at DL2, 2 at DL3, and 2 at DL4. One DL2 pt (4%) experienced Gr 4 CRS. CRS was managed with tocilizumab, corticosteroids, and vasopressors in 7 (70%), 3 (30%), and 1 (10%) pts at DL2, respectively, and 1 DL3 pt (50%) received tocilizumab. Median (range) time to CRS onset was 9 (1-36) d and resolution was 5 (1-18) d. Five pts (11%) had immune effector cell-associated neurotoxicity syndrome (ICANS) events: 3 at DL2 and 2 DL4. Two DL2 pts (7%) experienced Gr 3 ICANS (no pts experienced Gr 4-5). Median (range) time to onset and resolution of ICANS was 16 (6-28) and 16 (1-36) d, respectively. ICANS management was based on dexamethasone, methylprednisolone, and anakinra in 2 (67%), 1 (33%), and 1 (33%) pts at DL2, respectively, and 1 DL4 pt (50%) received dexamethasone. Median time to peak rapcabtagene autoleucel expansion was delayed compared with tisagenlecleucel: 16 d at DL2 vs 9 d in JULIET. At a 25-fold lower dose, rapcabtagene autoleucel expansion at DL2 was comparable by qPCR to tisagenlecleucel expansion in JULIET. Expansion increased from DL1 to DL2 with no further increases at higher doses. Data from DL2 show CAR transgene was detectable by qPCR in 1 out of 2 pts with 12 mo follow-up. scRNAseq analysis shows the rapcabtagene autoleucel manufacturing process preserves T-cell fitness by retaining the composition of cell populations from apheresis to final product through the short manufacturing time. scRNAseq analysis also suggests that certain characteristics of the final product composition may lead to improved CR rates at 3 mo. B-cell aplasia (≤50 CD19+ cells/μL) was established before/after rapcabtagene autoleucel in all pts. In responders, B-cell aplasia persisted for ≥8 mo. Conclusions: Rapcabtagene autoleucel is a potent new CD19-directed CAR-T cell tx with distinct cellular kinetics, durable efficacy, and a manageable safety profile. DL2 (12.5×106) CAR+ viable T cells is the recommended dose for Phase III studies, based on the CR rate, favorable safety profile, and cellular kinetics. Updated results with expanded cellular kinetics and biomarker analyses will be presented at the meeting. Figure 1View largeDownload PPTFigure 1View largeDownload PPT Close modal

Iptacopan (LNP023) is an oral, small-molecule, first-in-class, highly potent proximal complement inhibitor that specifically binds factor B and inhibits the alternative complement pathway. Iptacopan is currently in development as a targeted treatment of paroxysmal nocturnal hemoglobinuria and multiple other complement-mediated diseases. In this study, the absorption, distribution, metabolism, and excretion (ADME) of iptacopan was characterized in six healthy volunteers after a single 100 mg oral dose of [14C]iptacopan. This was supplemented with an in vivo rat ADME study and metabolite exposure comparisons between human, rat, and dog, in addition to in vitro assays, to better understand the clearance pathways and enzymes involved in the metabolism of iptacopan. The fraction of [14C]iptacopan absorbed was estimated to be about 71%, with a time to maximum concentration of 1.5 hours and elimination half-life from plasma of 12.3 hours. Following a single dose of [14C]iptacopan, 71.5% of the radioactivity was recovered in feces and 24.8% in urine. [14C]iptacopan was primarily eliminated by hepatic metabolism. The main biotransformation pathways were oxidative metabolism via CYP2C8, with M2 being the major oxidative metabolite, and acyl glucuronidation via UGT1A1. The two acyl glucuronide metabolites in human plasma, M8 and M9, each accounted for ≤ 10% of the total circulating drug-related material; systemic exposure was also observed in toxicology studies in rat and dog, suggesting a low risk associated with these metabolites. Binding of iptacopan to its target, factor B, in the bloodstream led to a concentration-dependent blood:plasma distribution and plasma protein binding of [14C]iptacopan. SIGNIFICANCE STATEMENT: We characterized the pharmacokinetics, excretion, metabolism and elimination of [14C]iptacopan (an oral, selective small-molecule inhibitor of factor B) in healthy human subjects. [14C]iptacopan was primarily eliminated by metabolism. The primary biotransformation pathways were oxidative metabolism via CYP2C8 and acyl glucuronidation via UGT1A1. Direct secretion of iptacopan into urine and potentially bile represented additional elimination mechanisms. Binding of iptacopan to its target, factor B, in the bloodstream led to a concentration-dependent blood:plasma distribution and plasma protein binding of [14C]iptacopan.

This annual review is the eighth of its kind since 2016 (Baillie et al. 2016, Khojasteh et al. 2017, Khojasteh et al. 2018, Khojasteh et al. 2019, Khojasteh et al. 2020, Khojasteh et al. 2021, Khojasteh et al. 2022). Our objective is to explore and share articles which we deem influential and significant in the field of biotransformation.

Tisagenlecleucel demonstrated high response rates and a manageable safety profile in adults with relapsed/refractory diffuse large B-cell lymphoma (r/r DLBCL) in the JULIET trial. However, lack of response and chimeric antigen receptor (CAR) T-cell exhaustion were observed in patients with programmed cell death protein 1 (PD-1) overexpression. Hence, pembrolizumab, a PD-1 inhibitor, was hypothesized to improve efficacy and cellular expansion of CAR T-cells in vivo. Here, we report the final analysis of the PORTIA trial in adult patients with r/r DLBCL who had & GE;2 prior lines of therapy and had an Eastern Cooperative Oncology Group performance status of & LE;1. Patients received 1 tisagenlecleucel infusion on day 1. Pembrolizumab (200 mg) was given every 21 days, for up to 6 doses. Three cohorts initiated pembrolizumab on days 15 (n = 4), 8 (n = 4), or -1 (n = 4). Safety, efficacy, cellular kinetics, and biomarker analyses were included. Tisagenlecleucel plus pembrolizumab was feasible and showed a manageable safety profile, without dose-limiting toxicities. Emerging efficacy with tisagenlecleucel was observed when pembrolizumab was given the day before tisagenlecleucel; however, the limited patient sample and short follow-up do not allow for definitive conclusions. Adding pembrolizumab to tisagenlecleucel did not augment the cellular expansion of tisagenlecleucel but delayed peak expansion if given the day before tisagenlecleucel (NCT03630159).

Polycomb Repressive Complex 2 (PRC2) plays an important role in transcriptional regulation during animal development and in cell differentiation, and alteration of PRC2 activity has been associated with cancer. On a molecular level, PRC2 catalyzes methylation of histone H3 lysine 27 (H3K27), resulting in mono-, di-, or trimethylated forms of H3K27, of which the trimethylated form H3K27me3 leads to transcriptional repression of polycomb target genes. Previously, we have shown that binding of the low-molecular-weight compound EED226 to the H3K27me3 binding pocket of the regulatory subunit EED can effectively inhibit PRC2 activity in cells and reduce tumor growth in mouse xenograft models. Here, we report the stepwise optimization of the tool compound EED226 toward the potent and selective EED inhibitor MAK683 (compound 22) and its subsequent preclinical characterization. Based on a balanced PK/PD profile, efficacy, and mitigated risk of forming reactive metabolites, MAK683 has been selected for clinical development.

Comparative studies of mortality in the wild are necessary to understand the evolution of aging; yet, ectothermic tetrapods are underrepresented in this comparative landscape, despite their suitability for testing evolutionary hypotheses. We present a study of aging rates and longevity across wild tetrapod ectotherms, using data from 107 populations (77 species) of nonavian reptiles and amphibians. We test hypotheses of how thermoregulatory mode, environmental temperature, protective phenotypes, and pace of life history contribute to demographic aging. Controlling for phylogeny and body size, ectotherms display a higher diversity of aging rates compared with endotherms and include phylogenetically widespread evidence of negligible aging. Protective phenotypes and life-history strategies further explain macroevolutionary patterns of aging. Analyzing ectothermic tetrapods in a comparative context enhances our understanding of the evolution of aging.

LYS006 is a potent leukotriene A4 hydrolase inhibitor currently in clinical development for long-term treatment of various neutrophil-driven inflammatory conditions. Here, we present pharmacokinetics from the first-in-human study with complementary metabolism and transporter profiling data. The randomized first-in-human study included nine cohorts receiving 5-2*100 mg of LYS006 or placebo, a crossover food-effect part, and a multiple-dose part consisting of two fasted (5 mg and 15 mg once daily) and three fed cohorts (20-80 mg twice a day) of LYS006 or placebo. LYS006 and metabolites were assessed in plasma and urine, and transporters involved in LYS006 disposition were analyzed in vitro. Systemic plasma exposure increased with dose; steady-state exposure was dose proportional up to 40 mg twice a day. Steady state was achieved after ∼3 days, with mean accumulation of 2.1-fold for 5 mg once daily and ≤1.4-fold for all higher doses. Despite limited accumulation, a long terminal half-life (T1/2) was observed. The long T1/2 and saturable binding to blood cells, which causes a highly nonlinear blood-to-plasma distribution, reflect a strong impact of target binding on drug distribution at lower concentrations. Skin biopsy and blister fluid concentration data indicated saturable binding in the former but not the latter, suggesting saturable binding in tissues beyond blood. Major excretion of LYS006 (∼90% of dose) through urine at steady state triggered renal transporter investigations that identified LYS006 as a substrate of organic anion transporter (OAT)3, OAT4, breast cancer resistance protein, and multidrug resistance-associated protein 4. Seven metabolites were identified in human plasma and urine, comprising only 4% of the dose recovered in urine at steady state. SIGNIFICANCE STATEMENT: Pharmacokinetic data from a first-in-human study combined with in vitro work support dose and regimen selection for patient studies with LYS006 and provide guidance on drug interaction investigations and other clinical pharmacology work needed for further development. Mass balance information at steady state without the use of a radiolabel, skin concentrations, and identification of the major clearance pathway, as well as the transporters driving elimination, make this a particularly conclusive early study despite nonlinear pharmacokinetics impacted by target binding.

LSZ102 is an orally bioavailable selective oestrogen receptor degrader in clinical development for the treatment of breast cancer. Preclinical studies showed efficacy in xenograft models on oral dosing. However, oral bioavailability was relatively low in several preclinical species (7-33%), and was associated with first-pass metabolism, particularly intestinal first-pass. To investigate metabolism and first-pass effects, metabolites were analysed in human plasma samples after oral dosing of LSZ102 to patients, rat plasma samples after oral dosing of [C-14]LSZ102, and in vitro incubations of [C-14]LSZ102 with human and rat hepatocytes and intestinal S9 fractions. The kinetics of human sulfotransferase (SULT) enzymes potentially involved in metabolism of LSZ102 was characterised. Sulphate metabolites were found to be the major components in human plasma, as well as in human hepatocytes and intestinal S9 fractions. Contrastingly, glucuronidation was predominant in rat plasma, hepatocytes and intestinal S9. LSZ102 was found to be metabolised by several human SULTs expressed in liver and intestine. The combined metabolism data in rat and human provide supporting evidence for an extensive intestinal first-pass metabolism effect via sulphation in human but glucuronidation in rat. As LSZ102 is metabolised by a number of different SULTs, drug-drug interactions resulting from the inhibition of one SULT are unlikely. Despite the observed species difference in metabolism, the major human metabolites of LSZ102, sulphate M5, glucuronide M4, and secondary glucuronide/sulphate metabolite M12, have no or weak pharmacological activity and are not considered a toxicity risk as they are phase II conjugative metabolites.

Understanding how animal populations respond to environmental factors is critical because large-scale environmental processes (e.g., habitat fragmentation, climate change) are impacting ecosystems at unprecedented rates. On an overgrazed floodplain in north-western Australia, a native rodent (Pale Field Rat, Rattus tunneyi ) constructs its burrows primarily beneath an invasive tree (Chinee Apple, Ziziphus mauritiana ) rather than native trees. The dense thorny foliage of the Chinee Apple may allow high rat densities either because of abiotic effects (shade, in a very hot environment) or biotic processes (protection from trampling and soil compaction by feral horses, and/or predation). To distinguish between these hypotheses, we manipulated Chinee Apple foliage to modify biotic factors (access to horses and predators) but not shade levels. We surveyed the rat population with Elliott traps under treatment and control trees and in the open woodland, in two seasons (the breeding season—January, and the nesting season—May). In the breeding season, we ran giving-up density experiments (GUD) with food trays, to assess the perceived risk of predation by rats across our three treatments. Selective trimming of foliage did not affect thermal regimes underneath the trees but did allow ingress of horses and we observed two collapsed burrows as a consequence (although long term impacts of horses were not measured). The perceived predation risk also increased (GUD values at food trays increased) and was highest in the open woodland. Our manipulation resulted in a shift in rat sex ratios (indicating female preference for breeding under control but not foliage-trimmed trees) and influenced rat behaviour (giving-up densities increased; large dominant males inhabited the control but not treatment trees). Our data suggest that the primary benefit of the Chinee Apple tree to native rodents lies in physical protection from predators and (potentially) feral horses, rather than in providing cooler microhabitat.

Background: Chimeric antigen receptor (CAR)-T cells are highly effective in patients (pts) with multiple myeloma (MM), but duration of response can be limited, and pts with rapidly progressing disease require a fast and reliable CAR-T cell manufacturing process. Here, we report initial clinical data from a Phase I trial assessing PHE885 manufactured using the T-Charge TM process and characterization of in vivo expansion, suggesting a preserved T-cell stemness (T scm) phenotype in pts with relapsed/refractory (r/r) MM (NCT04318327). Methods: PHE885 is a unique and fully human BCMA CAR-T cell product manufactured using the novel T-Charge TM platform, which reduces ex vivo culture time to about 24 hours and takes <2 days to manufacture the final product, thereby relying entirely on in vivo expansion after CAR-T cell infusion. Pts with MM r/r to ≥2 prior lines of treatment (tx), including an immunomodulatory drug, proteasome inhibitor, and an anti-CD38 monoclonal antibody, were eligible. Pts received fludarabine and cyclophosphamide for lymphodepletion prior to a single PHE885 intravenous injection. Primary objectives were safety, including dose-limiting toxicities (DLTs) and adverse events (AEs). Secondary objectives were clinical responses, evaluation of the T-Charge TM process, and pharmacokinetic properties. Results: As of data cut (April 1, 2021), 7 pts were enrolled in the dose escalation portion; 1 pt failed screening (prolonged QTc), and 6 pts were successfully infused with PHE885. All pts were heavily pretreated, penta-refractory, and refractory to the last line of tx. Fixed doses received were 5×10 6 (n=5) and 14.3×10 6 CAR+ T cells (n=1). All 6 pts were eligible for safety and efficacy. Two DLTs were reported: asymptomatic grade 3 transaminitis in the pt infused with 14.3×10 6 CAR+ T cells, and asymptomatic grade 4 lipase increased in 1 pt infused with 5×10 6 CAR+ T cells. Treatment-related grade ≥3 AEs included anemia and neutropenia in all pts; thrombocytopenia (n=4, 67%); and leukopenia, cytokine release syndrome (CRS), ALT and AST increase, and decreased blood fibrinogen (each n=2, 33%). All pts experienced grade ≤3 CRS per Lee 2014 criteria; median times to CRS onset and resolution were 7 d (range, 4-9 d) and 22 d (range, 10-27 d), respectively. All pts received at least 1 dose each of steroids and tocilizumab; 3 pts received anakinra to manage CRS. Two pts experienced grade 2 neurotoxicity related to PHE885. Both events were nonserious and temporally associated with grade 3 CRS. No deaths occurred on study. At 1 mo after tx, all pts had achieved at least a partial response (PR), with complete response (CR) in 1 pt (17%) and very good PR in 2 pts (33%). Of 4 pts evaluable at 3 mo after tx, 2 had stringent CR, 1 had PR, and 1 pt in PR experienced progressive disease, presumed to be due to loss of BCMA. Of 3 pts evaluable for minimal residual disease (MRD) at 1 mo after tx, all were MRD negative: 2 at sensitivity of 10 -6 and 1 at 10 -5. Robust cellular expansion was observed in all pts via qPCR and flow cytometry; maximum expansion (geometric mean C max) was 283000 copies/μg by qPCR and 69.3% of circulating T cells by flow cytometry. Maximum expansion was reached by 30 d, with median T max of 21.1 d by qPCR (16.4 d by flow cytometry). PHE885 was detectable in peripheral blood up to the latest measured sample for each pt (6 mo for the longest followed pt; range of follow-up, 1-6 mo). A naïve-like T-cell phenotype (T naïve+T scm) was preserved during manufacturing of all PHE885 products. Conclusions: Initial data from this Phase I study demonstrate that low doses of BCMA CAR-T cells manufactured by T-Charge TM in <2 days have encouraging clinical activity and a manageable safety profile in pts with r/r MM. PHE885 CAR-T cells expand rapidly in vivo, persist at relatively high levels for prolonged periods, and demonstrate a relatively immature T-cell phenotype. The trial is ongoing and updated data will be presented at the annual meeting. Clinical trial information: NCT04318327 Figure 1 Figure 1. Sperling: Adaptive: Consultancy. Nikiforow: Kite/Gilead: Other: ad HOC Advisory Boards; Novartis: Other: ad Hoc Advisory Boards; Iovance: Other: ad Hoc Advisory Boards; Glaxo Smith Kline (GSK): Other: ad Hoc Advisory Boards. Nadeem: Bristol Myer Squibb: Consultancy; GSK: Consultancy; Adaptive: Consultancy; Karyopharm: Consultancy; Takeda: Consultancy. Mo: Eli Lilly: Consultancy; Epizyme: Consultancy; GSK: Consultancy, Membership on an entity's Board of Directors or advisory committees; Janssen: Honoraria; Karyopharm: Honoraria, Membership on an entity's Board of Directors or advisory committees; Sanofi: Honoraria, Membership on an entity's Board of Directors or advisory committees; BMS: Membership on an entity's Board of Directors or advisory committees; AbbVIE: Consultancy. Anderson: Sanofi-Aventis: Membership on an entity's Board of Directors or advisory committees; Pfizer: Membership on an entity's Board of Directors or advisory committees; Janssen: Membership on an entity's Board of Directors or advisory committees; Gilead: Membership on an entity's Board of Directors or advisory committees; Bristol Myers Squibb: Membership on an entity's Board of Directors or advisory committees; Millenium-Takeda: Membership on an entity's Board of Directors or advisory committees; Celgene: Membership on an entity's Board of Directors or advisory committees; Scientific Founder of Oncopep and C4 Therapeutics: Current equity holder in publicly-traded company, Current holder of individual stocks in a privately-held company; AstraZeneca: Membership on an entity's Board of Directors or advisory committees; Mana Therapeutics: Membership on an entity's Board of Directors or advisory committees. Ikegawa: Bristol Myers Squibb: Honoraria. Shaw: Orchard Therapeutics, Ltd: Current equity holder in publicly-traded company. Ansari: Novartis: Current Employment. Quinn: Novartis: Current Employment, Current equity holder in publicly-traded company. Pearson: Novartis: Current Employment, Current equity holder in publicly-traded company. Hack: Novartis: Current Employment. Treanor: Novartis: Current Employment, Current holder of individual stocks in a privately-held company, Divested equity in a private or publicly-traded company in the past 24 months, Patents & Royalties: no royalties as company-held patents. Bu: Novartis: Current Employment, Patents & Royalties: Co-inventor on patent applications. Mataraza: Novartis: Current Employment, Current holder of stock options in a privately-held company. Rispoli: Novartis: Current Employment. Credi: Novartis: Current Employment, Current equity holder in publicly-traded company, Divested equity in a private or publicly-traded company in the past 24 months. Ritz: Amgen: Research Funding; Equillium: Research Funding; Kite/Gilead: Research Funding; Avrobio: Membership on an entity's Board of Directors or advisory committees; Akron: Consultancy; Biotech: Consultancy; Blackstone Life Sciences Advisor: Consultancy; Clade Therapeutics, Garuda Therapeutics: Consultancy; Immunitas Therapeutic: Consultancy; LifeVault Bio: Consultancy; Novartis: Consultancy; Rheos Medicines: Consultancy; Talaris Therapeutics: Consultancy; TScan Therapeutics: Consultancy. De Vita: Novartis: Current Employment. Munshi: Celgene: Consultancy; Amgen: Consultancy; Takeda: Consultancy; Adaptive Biotechnology: Consultancy; Abbvie: Consultancy; Oncopep: Consultancy, Current equity holder in publicly-traded company, Other: scientific founder, Patents & Royalties; Janssen: Consultancy; Karyopharm: Consultancy; Novartis: Consultancy; Pfizer: Consultancy; Legend: Consultancy; Bristol-Myers Squibb: Consultancy.