First-in-human Research Articles

LAMP1 targeting of the large T antigen of Merkel cell polyomavirus results in potent CD4 T cell responses and tumor inhibition.

Most cases of Merkel cell carcinoma (MCC), a rare and highly aggressive type of neuroendocrine skin cancer, are associated with Merkel cell polyomavirus (MCPyV) infection. MCPyV integrates into the host genome, resulting in expression of oncoproteins including a truncated form of the viral large T antigen (LT) in infected cells. These oncoproteins are an attractive target for a therapeutic cancer vaccine. We designed a cancer vaccine that promotes potent, antigen-specific CD4 T cell responses to MCPyV-LT. To activate antigen-specific CD4 T cells in vivo, we utilized our nucleic acid platform, UNITE™ (UNiversal Intracellular Targeted Expression), which fuses a tumor-associated antigen with lysosomal-associated membrane protein 1 (LAMP1). This lysosomal targeting technology results in enhanced antigen presentation and potent antigen-specific T cell responses. LTS220A, encoding a mutated form of MCPyV-LT that diminishes its pro-oncogenic properties, was introduced into the UNITE™ platform. Vaccination with LTS220A-UNITE™ DNA vaccine (ITI-3000) induced antigen-specific CD4 T cell responses and a strong humoral response that were sufficient to delay tumor growth of a B16F10 melanoma line expressing LTS220A. This effect was dependent on the CD4 T cells' ability to produce IFNγ. Moreover, ITI-3000 induced a favorable tumor microenvironment (TME), including Th1-type cytokines and significantly enhanced numbers of CD4 and CD8 T cells as well as NK and NKT cells. Additionally, ITI-3000 synergized with an α-PD-1 immune checkpoint inhibitor to further slow tumor growth and enhance survival. These findings strongly suggest that in pre-clinical studies, DNA vaccination with ITI-3000, using the UNITE™ platform, enhances CD4 T cell responses to MCPyV-LT that result in significant anti-tumor immune responses. These data support the initiation of a first-in-human (FIH) Phase 1 open-label study to evaluate the safety, tolerability, and immunogenicity of ITI-3000 in patients with polyomavirus-positive MCC (NCT05422781).

Intrauterine Vacuum-Induced Haemorrhage-Control Device: A Novel Approach For Pph.

Madam, Postpartum haemorrhage (PPH), defined as postpartum blood loss of > 1000 mL, is a life-threatening emergency and the leading cause of maternal mortality accounting for 25% of maternal deaths worldwide (1). PPH can lead to significant morbidity, including shock, ARDS, coagulopathy, infertility due to hysterectomy, and even mortality (4). Uterine atony is the most common cause, accounting for 80% of all cases of PPH (1) (2). Active management of the third stage of labour consisting of a triad of oxytocin, controlled cord traction, and uterine massage can reduce the incidence of PPH by 60% (5). If abnormal uterine bleeding ensues, PPH protocols are activated, including uterine balloon tamponade, uterine packing, uterine artery embolization, or hysterectomy (1, 2). The Jada System (novel intrauterine vacuum-induced haemorrhage-control device) approved by the U.S. FDA in August 2020, utilizes a low-level vacuum to induce negative pressure in the uterine cavity that facilitates uterine contraction to constrict myometrial blood vessels that can help with uterine atony (1). The device is used in patients with PPH where standard PPH treatments have failed or are contraindicated (1). It is a soft medical-grade silicone that attenuates the risk of tissue trauma and can be placed trans-vaginally after 3 cm of cervical dilation after vaginal birth and C-section (1,2). Ultrasound is used to check correct device placement, along with real-time quantification of the expelled blood from the uterine cavity into the graduated canister. The device can be placed for 1.5 hours to 24 hours inside the uterus. The device can be removed after evaluation of evacuated blood and palpation for a firm uterus, both signifying control of the hemorrhage (2). A First-in-Human (FIH) feasibility study conducted in Indonesia on 10 participants with atony-related PPH showed that the device was placed effectively, and bleeding was controlled in under 2 minutes with no unfavorable outcome in any participants (1) (3). The study was conducted with 107 participants of which two-thirds had atony-related PPH with failed medical treatment (1). The Per Protocol showed a 99% success rate in effectively controlling PPH (2). Bleeding halted in a minimum of 3 minutes, the treatment duration was around 3.2 hours and 98% of users regarded it as convenient to use (1). Adverse events included endometritis and vaginal infections all of which were resolved with adequate treatment (2). ---Continue

Early Safety and Performance of the Premounted Dry-Pericardium Vienna Self-Expandable Transcatheter Aortic Valve System: 30-Day Outcomes of the First-in-Human VIVA Feasibility Study

The purpose of this first-in-human (FIH) study was to determine the safety and feasibility of the transfemoral premounted dry-pericardium Vienna Self-Expandable Supra-Annular Aortic Valve System. This novel system is repositionable and retrievable and comes already premounted on the delivery system, eliminating the need for assembly and crimping of the device before valve implantation. This is a prospective, nonrandomized, single-arm, single-center, first-stage FIH feasibility study, which will be followed by a second-stage pivotal, multicenter, multinational study in symptomatic patients with severe aortic stenosis. The first-stage FIH study evaluated the safety and feasibility of the device in 10 patients with severe aortic stenosis based on recommendations by the Valve Academic Research Consortium-2 for transcatheter aortic valve implantations. The mean patient age was 79±5years, 60% were male, and all patients were in New York Heart Association functional class II to III. The primary safety end point was successful when all patients were alive at 30-day follow-up. Device and technical success were observed in all patients. Two patients had a stroke, 1 of which occurred 5days after the procedure. New permanent pacemakers were implanted in 2 patients (22.2%), of which only 1 was because of complete heart block. Only 1 patient (10%) had moderate paravalvular leak at 30days. After the procedure, the mean aortic valve gradient decreased from 48.7±10.8mmHg to 8.8±4.3mmHg. In conclusion, this FIH feasibility study demonstrates successful procedural feasibility, with no 30-day mortality and favorable valve hemodynamic performance, leading to an improvement in quality of life. ClinicalTrials.gov identifier NCT04861805.

The new S7B/E14 Q&A document provides additional opportunities to replace the thorough QT study.

Since 2015, concentration-QTc analysis can be used to exclude that a drug has a concerning effect on the QTc interval. This has enabled replacing the designated TQT study by implementation of serial ECGs into routine clinical pharmacology studies, such as the First-in-Human (FIH) study. This has led to an increased proportion of FIH studies with this added objective of QT evaluation with the intention of replacing the TQT study. With the more recent, February 2022 revision of the S7B/E14 Q&A document, nonclinical assays/studies can be brought into the process of regulatory decisions at the time of marketing application. If the hERG and the non-rodent in vivo study are conducted according to described best practices, the previous requirement that a QTc effect > 10 ms must be excluded in healthy subjects at plasma concentrations 2-fold above what can be seen in patients can be reduced to covering concentrations seen in patients. For drugs that cannot be safely given in high doses to healthy subjects, ECG evaluation is often performed at the therapeutic dose in patients. If a QTc effect > 10 ms can be excluded, an argument can be made that the drug should be considered as having a low likelihood of proarrhythmic effects due to delayed repolarization. In this article, we describe what clinicians involved in early clinical development need to understand in terms of the hERG and in vivo studies to determine whether these meet best practices and therefore can be used in an integrated clinical/nonclinical QT/QTc risk assessment. This article is protected by copyright. All rights reserved.

The role of WTX212, an erythrocyte-anti-PD1 antibody conjugate, in anti-tumor activities in tumor models and cancer patients with acquired resistance to immunotherapy.

29 Background: Despite the success of immune-checkpoint blockade (ICB) treatments, a considerable proportion of patients cannot benefit from ICB therapy due to acquired resistance. Recent studies have revealed that successful immunotherapy drives new immune responses arising from peripheral immune system instead of reinvigorating the pre-existing responses in the tumor. Here we designed WTX212, autologous engineered red blood cells (RBCs) conjugated with anti-PD1 antibodies capable of activating the peripheral immune system. We also evaluated its anti-cancer activities in anti-PD1 non-responsive tumor models and a first-in-human (FIH) trial. Methods: The anti-tumor efficacy of WTX212 was evaluated in both PD1 responsive (MC38 colorectal cancer) and non-responsive (KP lung cancer and pB3 breast cancer) mouse tumor models (n=7 / group). Mice were monitored twice a week for clinical signs and tumor sizes. The mechanism of action was investigated in splenectomized mice and by analyzing the biodistribution of WTX212 using a radiolabeling method. The immune landscape was also profiled through cytof mass and scRNA-seq analyses in the spleen, tumor and peripheral blood. The FIH trial (NCT05707325) explores safety, pharmacokinetics and mechanism in cancer patients with acquired resistance to ICB. WTX212 was manufactured by covalently engineering anti-PD1 antibody with RBCs isolated from patients. By 11th April 2023, 3 patients have been enrolled and received at least one dose of WTX212 (20*1010 cells, IV, Q3W). Results: Treatment of WTX212 significantly suppressed tumor growth up to 100% in anti-PD1 responsive and non-responsive tumor models. Unlike antibodies, WTX212 primarily distributed to the spleen and vascular system. The anti-tumor effect of WTX212 was abrogated in corresponding splenectomized mice. Compared to anti-PD1 antibody, single-cell analysis identified the immune landscape remodeling in the spleen from WTX212-treated mice, with down-regulation of PD-L1+ myeloid-derived suppressor cells (MDSCs) and up-regulation of effector CD8+ T cells. In the FIH trial, 3 patients have been administered with total thirteen cycles of WTX212. No treatment-related AEs greater than Grade 2 were observed. WTX212 remained in the peripheral blood day 21 post transfusion. WTX212 rapidly activates peripheral immune systems with decreased MDSCs, Tregs and increased effector T cells in peripheral blood from all patients. The first patient who received six cycles of WTX212 treatment demonstrated stable disease with a 20% reduction at the target lesion. Conclusions: WTX212 demonstrated anti-tumor activities by activating the peripheral immune system to overcome resistance to immunotherapy in both preclinical models and human patients. WTX212 is well-tolerated supporting the future clinical trials. Clinical trial information: NCT05707325 .

Population Target-Mediated Pharmacokinetic/Pharmacodynamic Modeling to Evaluate SPI-62 Exposure and Hepatic 11β-Hydroxysteroid Dehydrogenase Type 1 (HSD-1) Inhibition in Healthy Adults.

SPI-62 is a small-molecule 11β-hydroxysteroid dehydrogenase type 1 (HSD-1) inhibitor exhibiting complicated nonlinear pharmacokinetics (PK) in human. Previously, we developed a target-mediated drug disposition (TMDD) model to characterize the substantial nonlinear PK of SPI-62. The aim of the current analysis was to perform population PK/PD analysis to further link SPI-62 exposure (i.e., PK) with its response (i.e., inhibition of hepatic HSD-1 activity) to gain a quantitative understanding of the SPI-62 dose-exposure-response relationship. PK and PD data from the first-in-human (FIH) clinical trials, including single ascending dose (SAD) and multiple ascending dose (MAD) studies, were used for model development. During the model development process, the final model selection was based on biological and physiological plausibility, goodness-of-fit plots, stability of parameter estimates, and objective function value. The nonlinear-mixed effect modeling (NONMEM) software was used for both the implementation of the PK/PD model and model simulation. SPI-62 plasma levels and hepatic HSD-1 inhibition over time following various dose regimens were simulated. The final model was a two-compartment TMDD model component for SPI-62 and an inhibitory Imax model component for hepatic HSD-1 activity. The TMDD-hepatic PD model that we established adequately characterized all remarkable PK and PD behaviors of SPI-62, such as extremely low plasma exposures following the first low doses, nonlinear PK turned into linear PK after repeated low doses, and substantial and long-lasting hepatic HSD-1 inhibition following low doses. SPI-62 was estimated to bind to the target with a second-order association rate constant (Kon) of 8.43 nM-1h-1 and first-order dissociation rate constant (Koff) value of 0.229 h-1, indicating that SPI-62 binds rapidly to, and dissociates slowly from, its pharmacological target. The estimated target capacity (Rtot) of 5460 nmol corresponds to approximately 2.2 mg of SPI-62, which comports well with the dose range in which PK nonlinearity is prominent. Model simulation results reveal that a 6 mg once-daily regimen can lead to long-lasting and substantial hepatic HSD-1 inhibition. A population TMDD-PD model that explains SPI-62 nonlinear PK and hepatic HSD-1 inhibition following different dose regimens in healthy adults was successfully established. Our simulation results provide a solid foundation for model-informed development of SPI-62.

Utilizing PK and PD Biomarkers to Guide the First-in-Human Starting Dose Selection of MTBT1466A: A Novel Humanized Monoclonal Anti-TGFβ3 Antibody for the Treatment of Fibrotic Diseases

MTBT1466A is a high-affinity TGFβ3-specific humanized IgG1 monoclonal antibody with reduced Fc effector function, currently under investigation in clinical trials as a potential anti-fibrotic therapy. Here, we characterized the pharmacokinetics (PK) and pharmacodynamics (PD) of MTBT1466A in mice and monkeys and predicted the PK/PD of MTBT1466A in humans to guide the selection of the first-in-human (FIH) starting dose. MTBT1466A demonstrated a typical IgG1-like biphasic PK profile in monkeys, and the predicted human clearance of 2.69 mL/day/kg and t1/2 of 20.4 days are consistent with those expected for a human IgG1 antibody. In a mouse model of bleomycin-induced lung fibrosis, changes in expression of TGFβ3-related genes, serpine1, fibronectin-1, and collagen 1A1 were used as PD biomarkers to determine the minimum pharmacologically active dose of 1 mg/kg. Unlike in the fibrosis mouse model, evidence of target engagement in healthy monkeys was only observed at higher doses. Using a PKPD-guided approach, the recommended FIH dose of 50 mg, IV, provided exposures that were shown to be safe and well tolerated in healthy volunteers. MTBT1466A PK in healthy volunteers was predicted reasonably well using a PK model with allometric scaling of PK parameters from monkey data. Taken together, this work provides insights into the PK/PD behavior of MTBT1466A in preclinical species, and supports the translatability of the preclinical data into the clinic.

Safety and pharmacokinetics of IBI112, an IL-23 monoclonal antibody, in Chinese healthy volunteers: a first-in-human phase 1 study

ABSTRACT Background Interleukin (IL) 23p19 monoclonal antibodies were efficacious and safe in the treatment of psoriasis. A first-in-human (FIH) study was conducted to evaluate the safety, tolerability, pharmacokinetics (PK) and immunogenicity of IBI112, a novel IL-23p19 monoclonal antibody. Methods In this FIH, randomized, double-blind, placebo-controlled, single-ascending-dose study, a subcutaneous (SC, 5–600 mg) or intravenous (IV, 100 and 600 mg) or placebo was administered to eligible healthy subjects. Safety was assessed by physical examinations, vital signs, laboratory tests, and electrocardiograms. Furthermore, non-compartment analysis and population PK modeling were conducted to characterize PK, and model-based simulation was applied to justify dose selection for psoriasis patients. Results A total of 46 subjects were enrolled, with 35 receiving IBI112 and 11 receiving placebo. No serious adverse events (SAEs) and no clinically significant adverse events were identified. After a single SC of IBI112, the median T max was 4–10.5 days, and the half-life (t1/2) ranged from 21.8 to 35.8 days. IBI112 exposures (Cmax and AUCinf) approached dose proportionality across 5–300 mg range. Conclusion IBI112 was well tolerated and safe at SC or IV dose up to 600 mg and showed a linear PK characteristics at SC dose from 5 to 300 mg. Clinical trial registration ClinicalTrial.gov NCT04511624

Early safety and feasibility of a first-in-class biomimetic transcatheter aortic valve - DurAVR.

TAVI is a widely accepted treatment for patients with severe aortic stenosis (AS). Despite the adoption of diverse therapies, opportunities remain to develop technologies tailored to provide optimal acute and potential long-term benefits, particularly around haemodynamics, flow and durability. We aimed to evaluate the safety and feasibility of the DurAVR transcatheter heart valve (THV), a first-in-class biomimetic valve, in the treatment of patients with symptomatic severe AS. This was a first-in-human (FIH), prospective, non-randomised, single-arm, single-centre study. Patients with severe, symptomatic AS of any surgical risk and who were eligible for the DurAVR THV prosthesis were recruited; they were assessed at baseline, 30 days, 6 months, and 1 year post-procedure for implant success, haemodynamic performance, and safety. Thirteen patients (73.9±6.4 years old, 77% female) were enrolled. The DurAVR THV was successfully implanted in 100% of cases with no device-related complications. One access site complication, one permanent pacemaker implantation, and one case of moderate aortic regurgitation occurred. Otherwise, no deaths, stroke, bleeding, reinterventions, or myocardial infarction were reported during any of the follow-up visits. Despite a mean annulus size of 22.95±1.09 mm, favourable haemodynamic results were observed at 30 days (effective orifice area [EOA] 2.00±0.17 cm2, and mean pressure gradient [MPG] 9.02±2.68 mmHg) and were sustained at 1 year (EOA 1.96±0.11 cm2, MPG 8.82±1.38 mmHg), resulting in zero patients with any degree of prosthesis-patient mismatch. Additionally, new valve performance measures derived from cardiovascular magnetic resonance displayed restoration of laminar flow, consistent with a predisease state, in conjunction with a mean coaptation length of 8.3±1.7 mm. Preliminary results from the FIH study with DurAVR THV demonstrate a good safety profile with promising haemodynamic performance sustained at 1 year and restoration of near-normal flow dynamics. Further clinical investigation is warranted to evaluate how DurAVR THV may play a role in addressing the challenge of lifetime management in AS patients.

#4328 CHK-336, A FIRST-IN-CLASS ORALLY ADMINISTERED LDH INHIBITOR: SAFETY, PK AND TARGET ENGAGEMENT IN A FIRST-IN-HUMAN PHASE 1 HEALTHY VOLUNTEER STUDY

Abstract Background and Aims CHK-336 is a first-in-class, orally bioavailable, liver-targeted small molecule lactate dehydrogenase (LDH) inhibitor for the treatment of primary hyperoxalurias and other kidney stone disorders caused by oxalate overproduction. The primary objectives of this first-in-human (FIH) study were characterization of the safety and pharmacokinetics (PK) of CHK-336 following single and repeat doses in healthy volunteers (HVs). Exploratory objectives were demonstration of proof of mechanism in HVs based on inhibition of hepatic oxalate production using a stable-label 13C2-glycolate tracer for hepatic LDH target engagement and characterization of the exposure-response relationship. Method This Phase 1, placebo-controlled (6:2 randomization within a cohort), dose escalation study explored single ascending (SAD, 15-500 mg) and multiple ascending (MAD, 30 mg and planned up to 500 mg QD, 14 consecutive days) doses. A total of 104 subjects will be enrolled in this study. A stable-label 13C2-glycolate tracer was administered orally at baseline and following CHK-336 administration to evaluate the inhibition of LDH-mediated production of [13C2]-oxalate by CHK-336, as a measure of hepatic LDH target engagement in HVs. Food-effect was evaluated following a single dose after a standard high fat meal. CHK-336 concentrations were determined in plasma and urine by a validated LC-MS/MS assay. Total oxalate and 13C2-oxalate were determined in urine by validated GC/MS assays. Results CHK-336 was generally well tolerated following single doses from 15 – 500 mg, with no dose-related trends in total adverse events (AEs) or types of AEs. There were no serious AEs, or severe treatment-related AEs (TRAEs). Treatment-emergent AEs were observed in 10 of 56 (17.9%) subjects, 7 (12.5%) of whom experienced TRAEs; all TRAEs were mild or moderate in severity. CHK-336 PK profiles were characterized with a median tmax of 6 hrs following absorption in fasted-state followed by bi-exponential decline and a terminal half-life of 18 ± 8 hrs. Dose-proportional increases in exposure AUC were observed from 15 up to 500 mg. Cmax increase was greater than dose-proportional at ≥60 mg with a concomitant decrease in median tmax from 6hr to 2hr. A high fat meal decreased CHK-336 AUC0-72h by 32% (AUC0-72h) and Cmax by 55%. Renal elimination of unchanged CHK-336 was quantitatively minor (<1% of administered dose). A direct effect inhibitory Imax-IC50 model adequately described the relationship between CHK-336 plasma concentrations and urinary 13C2-oxalate (% of control). Robust target engagement was demonstrated with an exposure-related reduction in urinary 13C2-oxalate from 15 – 60 mg, with maximum inhibition achieved at CHK-336 doses ≥60 mg. Conclusion CHK-336 is a first-in-class, orally administered, liver-targeted LDH inhibitor that was generally well-tolerated following single doses from 15 – 500 mg, with dose proportional increases in AUC exposure. Hepatic oxalate production was robustly reduced by CHK-336, as measured by urinary 13C2-oxalate, thus achieving proof of mechanism in HVs.

Development of a quantitative systems pharmacology (QSP) model to support dose optimization of DS-1103a (anti SIRPa antibody) in combination with trastuzumab deruxtecan in patients with cancer.

e14509 Background: DS-1103a, an anti-human signal regulatory protein α (SIRPα) monoclonal antibody (mAb), is designed to block the SIRPα-CD47 axis “Don’t Eat Me” signal and trigger phagocytosis of tumor cells when combined with an Fc-active antitumor mAb. DS-1103a is being developed as a combination therapy with trastuzumab deruxtecan (T-DXd; DS-8201a) as the antibody-dependent cellular phagocytosis (ADCP) enabling antibody. We developed a QSP model to support the first in human (FIH) intravenous dosing (IV) based on predicted intratumoral receptor occupancy (RO) within immunological synapses (the intercellular contact zone between macrophages and cancer cells) and corresponding ADCP activity. Methods: The QSP model mechanistically integrated DS-1103a plasma pharmacokinetics (PK), tumor distribution and binding of receptors to both antibodies and their ligands to simulate RO in the tumor microenvironment (TME). A proximal pharmacodynamics pathway model was first developed to estimate the intratumoral RO required to induce desired levels of ADCP for DS-1103a+T-DXd combination therapy. A human model was then developed to integrate DS-1103a PK with derived intratumormal RO in patients considering key human pathophysiological parameters, including SIRPα expression, tumor lesion permeability, SIRPα+ cell fractions in TME, tumor capillary radius, SIRPα internalization, CD47 expression and tumor lesion size. Virtual patient simulations were conducted in various cancer types to facilitate FIH dose selection. Results: The proximal pharmacodynamics pathway model quantitatively recapitulated the dose dependent in vitro ADCP activities for DS-1103a+T-DXd combination therapy. The intratumoral RO (within synapses) required to induce desired levels of ADCP activity were also derived. The human model predicted similar dose dependent intratumoral RO in various cancer types. Virtual patient simulations indicated that a flat dose of 100 mg Q3W IV DS-1103a could achieve steady-state intratumoral RO sufficient to reach half of the maximal ADCP activity and would be a suitable FIH starting dose. The predicted steady-state intratumoral RO after a flat dose of ≥1000 mg Q3W IV DS-1103a is well above the predicted intratumoral RO threshold to achieve maximum ADCP activity. Conclusions: The QSP model mechanistically characterized DS-1103a mechanism of action and linked PK to intratumoral RO and corresponding ADCP activity in both in vitro and in vivo setting. The model was used to derive the FIH starting dose and potentially clinically effective doses for DS-1103a in combination with T-DXd. This QSP model will be integrated into a large-scale disease platform to support dose expansion and further dose optimization as new clinical data emerge.

A phase 1/2 study of CFT1946, a novel, bifunctional degradation activating compound (BIDAC) degrader, of mutant BRAF V600 as monotherapy and in combination with trametinib, in mutant BRAF V600 solid tumors.

TPS3163 Background: BRAF is a protein kinase that acts as a signal transducer in the MAPK pathway. Mutant BRAF V600 is capable of uncontrolled signaling and is constitutively active and signals as a monomer, leading to hyperactivation of MEK, ERK, and dysregulation of cellular proliferation. Mutant BRAF V600 is a clinically-validated target in a variety of cancers including melanoma, colorectal cancer (CRC), non-small cell lung cancer (NSCLC), and anaplastic thyroid carcinoma (ATC). Currently approved BRAF inhibitors (BRAFi) result in paradoxical RAF activation as the mutant BRAF protein is still able to dimerize with WT BRAF, resulting in a dimeric signaling complex. CFT1946 is a novel, orally bioavailable BiDAC degrader that inhibits and degrades mutant BRAF V600 protein. Distinct from approved BRAFi, CFT1946 avoids paradoxical RAF activation as the degraded BRAF V600 mutant protein can no longer incorporate into a dimeric signaling complex. CFT1946 is selective for the mutant protein and spares WT BRAF V600. CFT1946 has demonstrated preclinical activity in BRAF V600 mutant in vitro and in vivo models, including models resistant to BRAFi. These preclinical data provide rationale for a first-in-human (FIH) study to evaluate CFT1946 in BRAF V600 mutant solid tumors. Methods: This is a FIH, open-label, multicenter, Phase 1/2 clinical trial to characterize the initial safety, tolerability, and preliminary efficacy of CFT1946 and CFT1946+trametinib in BRAF V600 mutant melanoma, NSCLC, CRC, ATC, and other non-CNS BRAF V600 mutant solid tumors. This study includes 2 phases: dose escalation Phase 1 comprising CFT1946 (Arm A) with a starting oral dose of 20 mg twice daily and CFT1946+trametinib (Arm B) as well as dose expansion Phase 2 comprising CFT1946 (Arm A1) and CFT1946+trametinib (Arms B1 and B2). Arm A1 and B1 will include BRAF V600 mutant melanoma and NSCLC with prior BRAFi therapy while Arm B2 will enroll BRAF V600 mutant NSCLC who are BRAFi-naïve. Phase 2 will be initiated once the RP2D has been identified. Eligible subjects are ≥18yo with documented BRAF V600 mutant cancers who have received ≥1 prior therapy. CFT1946 will be administered orally in 28-day cycles until disease progression or intolerable toxicity. Primary objectives include safety, tolerability, RP2D and preliminary antitumor activity of CFT1946 monotherapy and in combination with trametinib. Secondary objectives include assessment of pharmacokinetics and pharmacodynamics. Key inclusion criteria include documented evidence of a BRAF V600 mutation obtained from tumor tissue or liquid biopsy; at least 1 prior line of standard-of-care therapy for locally advanced or metastatic disease. The study is anticipated to enroll 101-122 patients across 11 participating US and European sites and is currently open to enrollment (NCT05668585). Clinical trial information: NCT05668585 .

A phase 1, first-in-human (FIH) study of autologous macrophages engineered to express an anti-HER2 chimeric antigen receptor (CAR) in participants (pts) with HER2-overexpressing solid tumors.

TPS2666 Background: Macrophages are abundant in the solid tumor microenvironment (sTME) and can promote tumor growth (M2) or enhance anti-tumor immunity (M1). CAR expression can redirect macrophage function to selectively target and phagocytose antigen overexpressing cancer cells. CAR-M can reprogram the sTME and present neoantigens to T cells, leading to epitope spreading and anti-tumor immunity. CT-0508 is comprised of autologous monocyte-derived proinflammatory macrophages expressing an anti-HER2 CAR. Pre-clinical studies showed that CT-0508 induced targeted cancer cell phagocytosis while sparing normal cells, decreased tumor burden, prolonged survival, and was safe. Notably, anti-HER2 CAR-M treatment led to activation of the sTME, with infiltration of CD8+ and CD4+ T cells, NK cells, dendritic cells, and increased activated CD8+ tumor infiltrating lymphocytes. In a pre-clinical anti-PD1 resistant solid tumor model, mice that received anti-HER2 CAR-M and anti-PD1 demonstrated improved tumor control, overall survival, and TME activation compared to single treatment alone, indicating synergy and capacity for CAR-M to sensitize solid tumors to checkpoint blockade. Methods: This Phase 1, First in Human study evaluates the safety, tolerability, cell manufacturing feasibility, trafficking, TME activation, and preliminary evidence of efficacy of investigational product CT-0508 in 18 participants (pts) with locally advanced (unresectable) /metastatic solid tumors overexpressing HER2. Pts previously treated with anti-HER2 therapies are eligible. Filgrastim mobilized autologous CD14+ monocytes are collected by apheresis, followed by manufacturing and cryopreservation. Group 1 pts (n = 9; enrollment complete) received fractionated doses of CT-0508 over Days 1, 3, and 5. Group 2 pts (n = 9) receive CT-0508 as a single infusion on D1. Additional cohorts include: CT-0508 co-administered with pembrolizumab and CT-0508 monotherapy administered intraperitoneally in pts with peritoneal predominant disease. Correlative assessments include pre- and post-treatment biopsies and blood samples for safety (immunogenicity), trafficking (PCR, RNA scope), CT-0508 persistence in blood and tumor, target antigen engagement, TME modulation (single cell RNA sequencing), immune response (TCR sequencing) and others. Clinical trial information: NCT04660929 .

First-in-human, phase 1a dose finding of LVGN6051 CD137/4-1BB agonistic antibody with or without pembrolizumab in patients with advanced solid tumors.

2525 Background: LVGN6051 is a conditional 4-1BB agonistic monoclonal antibody with Fc γ-receptor IIB selective binding in the tumor microenvironment for optimal activity. Preclinical studies showed potent antitumor activity by LVGN6051 alone and in combination with anti-PD-1 antibody. Methods: We conducted this first in human (FIH) multicenter phase 1 dose escalation study in the US. Eligible pts with advanced solid tumor malignancies received escalating doses of LVGN6051 alone or in combination with pembrolizumab 200 mg IV Q3W until unacceptable toxicity, progressive disease, or withdrawal of consent. Results: As of Jan 23, 2023, 55 pts were enrolled and received LVGN6051 alone with the dose range of 0.003–7 mg/kg (n=18), or combination therapy of LVGN6051 2 mg/kg + pembrolizumab (n=22) or LVGN6051 4 mg/kg + pembrolizumab (n=15). The median age was 58 years (range 20-83) and number of prior therapies was 5; 46 pts (84%) had ECOG PS 1 and 21 pts (38%) had received prior immune checkpoint inhibitors (ICI). In pts who received LVGN6051 alone, the MTD was not reached up to 7 mg/kg and the RP2D was selected as 4 mg/kg IV Q3W for tolerance. The RP2D for combination therapy was established as LVGN6051 4 mg/kg and pembrolizumab 200 mg IV Q3W. Pts received a median of 2.8 months and a mean of 4.0 months (range 0.5 – 19.2) of study treatment. 33 pts (60%) experienced any grade treatment-related adverse events (TRAEs) with noteworthy (> 5%) AST increased (27%), ALT increased (26%), thrombocytopenia (16%), infusion related reaction (IRR) (9%), fatigue (7%), lipase increased (6%), nausea (6%) and chills (6%). 14 pts (25%), 1 mono- and 13 combination therapy, showed ≥ grade 3 TRAEs: AST increased (11%), ALT increased (9%), thrombocytopenia (7%), fatigue (4%), IRR (2%), lipase increased (2%) and nausea (2%). 6 drug-related serious adverse events and 1 DLT (grade 4 thrombocytopenia), all in combination therapy, were reported. In 42 evaluable pts, the disease control rate (DCR) was 50%. Combination therapy showed that target lesions were reduced by 57%, 42% and 48% in melanoma (n=2) and pancreatic cancer (n=1), respectively. Among 11 melanoma pts (10 had progressed on anti-CTLA4 and anti-PD-1 therapy), 2 PR and 5 SD were observed per RECIST 1.1, including one being treated for 19+ months (26+ cycles). Pts with HNSqCC (n=1) and CRPC (n=1) also showed remarkable tumor shrinkage. Paired tumor biopsies for single cell RNAseq biomarker exploration confirmed activation of effector T cells following LVGN6051 treatment. Conclusions: We established the RP2Ds of LVGN6051 alone and in combination with pembrolizumab in this FIH phase 1a study. These regimens were well tolerated. Preliminary efficacy data showed encouraging anti-tumor activity in heavily pretreated pts who had progressed on ICI. Phase 1b dose expansion for the combination therapy is ongoing in pts with melanoma, GI malignancies and NSCLC. Clinical trial information: NCT04130542 .

A multi-cohort phase I/IIa clinical trial to evaluate the safety, tolerability, and pharmacokinetics of TST001 administered as a monotherapy, with nivolumab or standard of care in patients with locally advanced or metastatic solid tumors: TransStar101.

TPS4176 Background: Gastric cancer (GC) remains the 4th leading cause of cancer death worldwide, accounting for about 7.7% of all cancer related mortality. Despite recent approval of nivolumab in combination with chemotherapy, the median survival of treatment naïve Gastric Cancer/gastroesophageal junction cancer (G/GEJ) cancer is only approximately 14 months, even in patients with high CPS PD-L1. Targeting claudin 18.2 (CLDN18.2) in combination with chemotherapy is a clinically validated approach for patients with CLDN18.2 expressing advanced G/GEJ cancer. TST001 is a humanized monoclonal antibody with improved affinity to human CLDN18.2 and enhanced antibody-dependent cellular cytotoxicity (ADCC). In pre-clinical studies, TST001 treatment upregulates PD-L1 expression on CLDN18.2-positive tumor cells. The in vivo analysis showed anti-tumor efficacy of TST001 combined with anti-PD-1 antibody and chemotherapy was superior to combination of anti-PD-1 antibody with chemotherapy or combination of TST001 with chemotherapy. Promising anti-tumor activities have been observed in patients with advanced G/GEJ cancer who have been treated with TST001 alone or in combination with chemotherapy, making the combination of TST001, nivolumab and chemotherapy attractive. Methods: This is a multi-cohort, open-label, multi-center phase I/II first in human (FIH) study of TST001 administered as single agent, in combination with nivolumab or standard of care in the treatment of patients with locally advanced or metastatic solid tumors. Primary endpoints include characterization of TST001 safety profile and the maximum tolerated dose / recommended phase 2 dose. Secondary endpoints include pharmacokinetics, immunogenicity, pharmacodynamics, and efficacy. The study includes two parts. Part A (completed) is a dose escalation of TST001 as a monotherapy. Part B (ongoing) consists of three independent cohorts: cohort A includes combination TST001 + nivolumab+ leucovorin calcium (folinic acid), fluorouracil, and oxaliplatin (mFOLFOX6) as 1st line treatment for G/GEJ cancer; cohort B includes TST001 in combination with nivolumab in advanced pre-treated G/GEJ cancer; cohort C includes combination therapy of TST001, gemcitabine, and nanoparticle albumin-bound paclitaxel as 1st line treatment for advanced/metastatic pancreatic cancer. Multiple doses and schedules will be assessed during Part B. Conclusions: Combination of TST001 with nivolumab and chemotherapy has the potential to improve the outcomes of patients with advanced or metastatic CLDN18.2 expressing G/GEJ cancer. Data from this trial will support the selection of the optimal dose and dose regimen of TST001 in these combinations. Enrollment in the trial is ongoing. Clinical trial information: NCT04396821 .

First-in-human (FIH) phase I dose escalation study (part A) of the first oral allosteric modulator of phosphoinositide 3-kinase inhibitor delta (PI3Kδ) roginolisib in patients with advanced cancer and dose confirmation in uveal melanoma (part B).

3110 Background: The highly selective oral allosteric modulator of PI3Kδ, roginolisib (IOA-244), blocks the activity of PI3Kδ -dependent signalling, in both tumour cells and Tregs. Methods: Part A explored the continuous daily dosing of roginolisib at 10, 20, 40 and 80 mg in patients (pts) with solid tumours and Follicular Lymphoma (FL). Part B consists of dose confirmation cohorts, including uveal melanoma (UM) pts. Primary objective: safety of the anticipated biologically effective dose (BED), or the recommended phase 2 dose (RP2D). Secondary objectives: PK; PD (e.g., inhibition of CD63 expression on basophils, changes in immune cell subsets in peripheral blood); RECIST 1.1. or Lugano-based responses; PFS and OS. Exploratory studies: phenotypic changes in circulating immune cells by Cytometry by Time of Flight (CyTOF); response assessments by radiomics; analysis of circulating protein signatures via Olink proteomic. Results: Part A Solid Tumour (completed): Sixteen pts were treated in 4 cohorts, each with 4 pts. Pts characteristics: uveal melanoma (9/16; 56%), cutaneous melanoma (5/16; 31%) and pleural mesothelioma (2/16; 13%). Only Grade 1 and 2 AEs by CTCAE v5 were observed, including 2 cases of transient (lasting < 24 hrs) diarrhoea and 2 of AST/ALT elevation. Part A FL Cohort (completed): 8 pts were treated at 20 mg (n=4) and 80 mg (n=4). Grade 3 toxicities were transient and observed in 2/8 (25%) pts. 2/4 pts (50%) at the 80 mg had PR as per Lugano criteria. Neither in the solid tumour nor in the haematology pts treatment-emergent adverse events (TEAE) led to study drug discontinuation, immune related toxicity, or a Dose Limiting Toxicity. Subgroup evaluation: UM pts (Part A and Part B): 24 pts (Part A: 9 pts; Part B ongoing: 15 pts), of which 18 pts treated at 80 mg QD (RP2D). Mean time on treatment: 8.6 mo (range: 1.0-27.9 mo). ORR (RECIST 1.1): PR: 1/20 (5%); SD: 16/20 (80%). Median OS for Part A: 20.8 mo (5/9 with 4 pts alive); Part B: not determined; 1-year OS rate: Part A 66.7%; Part B: ongoing. Exploratory Investigations: Radiomics-based evaluation of CT images in pts with solid tumors assessed each metastatic organ, detecting mixed responses; peripheral proteomic evaluation detected changes in several cytokines and chemokines; CyTOF detected reduction in circulating Tregs associated with increased activated effector CD8+ T cells. Conclusions: Roginolisib is well tolerated at the 80 mg dose, shows signs of efficacy and induces phenotypic changes in the circulating immune cells. As best response at the RP2D, the most robust anti-tumour activity was observed in FL (50% PR) and UM pts (5% PR; 80% SD). Clinical trial information: NCT04328844 .

WTX212, an erythrocyte-anti-PD1 antibody conjugate, to demonstrate anti-tumor activities in tumor models and patients with cancer with acquired resistance to immunotherapy.

e14529 Background: Despite the success of immune-checkpoint blockade (ICB) treatments, a considerable proportion of patients cannot benefit from ICB therapy due to acquired resistance. One major challenge is the systemic suppression of immune cells induced by the tumor. Recent studies have revealed that successful immunotherapy drives new immune responses arising from peripheral immune system instead of reinvigorating the pre-existing responses in the tumor. Here we designed WTX212, autologous engineered red blood cells (RBCs) conjugated with anti-PD1 antibodies capable of activating the peripheral immune system. We also evaluated its anti-cancer activities in anti-PD1 non-responsive tumor models and a first-in-human (FIH) trial. Methods: The anti-tumor efficacy of WTX212 was evaluated in both PD1 responsive (MC38 colorectal cancer) and non-responsive (KP lung cancer and pB3 breast cancer) mouse tumor models (n=7 / group). Mice were monitored twice a week for clinical signs and tumor sizes. The mechanism of action was investigated in splenectomized mice and by analyzing the biodistribution of WTX212 using a radiolabeling method. The immune landscape was also profiled through cytof mass and scRNA-seq analyses in the spleen, tumor and peripheral blood. The FIH trial (NCT05707325) explores safety, pharmacokinetics and mechanism in cancer patients with acquired resistance to ICB. WTX212 was manufactured by covalently engineering anti-PD1 antibody with RBCs isolated from patients. By 6th Feb 2023, 3 patients have been enrolled and received at least one dose of WTX212 (20*1010 cells, IV, Q3W). Results: Treatment of WTX212 significantly suppressed tumor growth up to 100% in anti-PD1 responsive and non-responsive tumor models and activated tumor microenvironment with increased infiltrated T cells. Unlike antibodies, WTX212 primarily distributed to the spleen and vascular system. The anti-tumor effect of WTX212 was abrogated in corresponding splenectomized mice. Compared to anti-PD1 antibody, single-cell analysis identified the immune landscape remodeling in the spleen from WTX212-treated mice, with down-regulation of PD-L1+ myeloid-derived suppressor cells (MDSCs) and up-regulation of effector CD8+ T cells. In the FIH trial, 3 patients have been administered with total eight cycles of WTX212. No treatment-related AEs greater than Grade 2 were observed. WTX212 remained in the peripheral blood day 21 post transfusion. WTX212 rapidly activates peripheral immune systems with decreased MDSCs, Tregs and increased effector T cells in peripheral blood from all patients. Conclusions: WTX212 demonstrated anti-tumor activities by activating the peripheral immune system to overcome resistance to immunotherapy in both preclinical models and human patients. WTX212 is well-tolerated supporting the future clinical trials.

Phase II study on safety and efficacy of NMS-01940153E, an MPS1 inhibitor with first-in-class potential, in adult patients with unresectable hepatocellular carcinoma (HCC) previously treated with systemic therapy.

TPS4185 Background: Monopolar Spindle 1 (MPS1) kinase regulates the spindle assembly checkpoint (SAC) which ensures proper division of chromosomes during mitosis. MPS1 is overexpressed in several tumors, including hepatocellular carcinoma (HCC), where it correlates with tumor features and poor overall and disease-free survival. NMS-01940153E is a novel, highly potent and selective small molecule inhibitor of MPS1 kinase with long residence time and strong preclinical anti-tumor activity in different tumor types. In HCC lines, specifically, NMS-01940153E showed ~2-Log higher anti-proliferative activity compared to sorafenib, lenvatinib, and regorafenib. In a previous open-label first-in-human (FIH) study, CL1-81694-001 (EudraCT 2014-002023-10), signs of activity in HCC were detected. Recently, the treatment paradigm for advanced HCC has changed, with immunotherapy combinations in first line and TKIs shifted in later lines. However, the overall prognosis of patients with advanced HCC remains poor, and there is a strong need of new drugs in this setting. NMS-01940153E novel mechanism of action, inhibiting the SAC and interfering with genomic stability in HCC, may offer a new therapeutic option in HCC. Based on the promising FIH results, a Phase I/II study, MPSA-153-001 (EudraCT 2020-001002-26), was initiated in patients with HCC previously treated with more than one systemic therapy. Methods: The Phase II part of the MPSA-293-001 trial is designed as a two-stage study with an interim analysis for futility and safety rules for unacceptable toxicity. The primary objective is to assess the antitumor activity of NMS-01940153E in adult patients with unresectable HCC previously treated with systemic therapy measured as objective response rate (ORR) by investigator-assessed RECIST 1.1. Secondary endpoints are safety, PK, ORR as measured by investigator-assessed mRECIST, DoR, PFS and OS. Exploratory endpoints include biomarkers. NMS-01940153E is administered IV, on days 1, 8 and 15 every 4 weeks at the RP2D of 100 mg/m2/wk, which showed PK in a predicted active range. Key eligibility criteria are 1) diagnosis of HCC; 2) disease progression on standard-of-care treatment including an immune checkpoint inhibitor as first line and at least one TKI; 3) no more than 3 prior systemic treatment lines. Interim evaluation for futility will be undertaken as soon as the first 10 evaluable patients will be enrolled. If at least 1 responder is observed with no safety issues, enrollment will proceed up to 38 evaluable patients. Otherwise, the study will be terminated for futility. An independent DSMB will review the interim results and provide recommendation on the study progress. Recruitment is currently ongoing in Italy and Spain and an FDA “Study May Proceed Notification” was received in January 2023. Clinical trial information: NCT05630937 .

First‐in‐Human (FIH), Single‐ and Multiple‐Ascending‐Dose (SAD/MAD) studies in healthy subjects of E2511, a novel tropomyosin receptor kinase a (TrkA) positive allosteric modulator (PAM)

AbstractBackgroundCholinergic innervation is affected in multiple neurodegenerative diseases associated with cognitive dysfunction. Loss of cholinergic neurons in Alzheimer’s disease (AD) is correlated with cognitive impairment. Nerve growth factor (NGF) plays a major role in the maintenance and function of cholinergic neurons. The activation of NGF‐induced trophic signaling via TrkA could be a promising therapy for neurodegenerative diseases including AD. E2511 is a novel small molecule TrkA biased PAM that has shown reinnervative effects on cholinergic neurons in nonclinical studies (without NGF‐associated hyperalgesia). The main objectives of the E2511 FIH Phase 1 studies (SAD [completed] and MAD [ongoing]) are to evaluate the safety, tolerability and pharmacokinetics in healthy subjects.Methods: Both SAD and MAD are randomized, double‐blind and placebo‐controlled studies. The SAD evaluated 5 cohorts (n = 8/cohort) in adults and 1 cohort in elderly subjects (n = 5). Food effect was evaluated in one SAD cohort. Safety was evaluated through the review of adverse events, physical examinations, clinical laboratory tests, vital signs, electrocardiogram and electroencephalograms. Blood samples were collected for determination of plasma E2511 concentrations. Repeat dosing with E2511 (once daily for 14 days) is under evaluation in the MAD study.Results: Single doses of E2511 were safe and well‐tolerated across the investigated doses in adult and elderly subjects. There were no dose‐dependent nor severe treatment‐emergent adverse events (TEAEs). There were no clinically significant changes in the evaluated safety parameters on E2511 compared to placebo. Pharmacokinetic results show that E2511 was rapidly absorbed (tmax: 1 hour). Plasma half‐life was 3.2 hours. Plasma exposures (Cmax and AUC) increased dose proportionally over the investigated dose range. Food led to a decrease of 19% in Cmax and 15% in AUC compared to fasted conditions. Plasma exposures in elderly and younger adult subjects were comparable. Evaluation of E2511 safety, tolerability and PK/PD following multiple doses is ongoing.ConclusionE2511 presented an adequate safety and PK profile in healthy adults and elderly subjects. These results support further development of E2511 as a disease‐modifying therapy for neurodegenerative diseases.

Abstract ND04: BAY 2965501: A highly selective DGK- ζ inhibitor for cancer immuno-therapy with first-in-class potential

Abstract The second messenger diacyl glycerol (DAG) plays a key role in T cell receptor downstream signaling and thereby in T-cell activation. Diacylglycerol kinase zeta (DGK-ζ) is a lipid kinase that can down-modulate T-cell activation by catalyzing the conversion of DAG to phosphatidic acid, thereby acting as a ligand independent, intracellular immune checkpoint. Inhibition of DGK- ζ offers the potential to enhance T cell priming against suboptimal tumor antigens and to overcome multiple immune-suppressive mechanisms in the tumor microenvironment. Bayer AG in collaboration with the German Cancer Research Center (DKFZ) have developed BAY 2965501, a highly selective, orally available DGK-ζ inhibitor which shows a unique binding mode and good DMPK profile. The compound enhances the reactivity of human and mouse T-cells, both in the priming and the effector phase, and overcomes the inhibitory impact of suppressive factors, such as adenosine and prostaglandin E2. Oral dosing of BAY 2965501 shows T cell dependent efficacy in syngeneic, murine tumor models. Furthermore, this results in reactivation of exhausted T cells in vivo. Preclinical safety studies showed only mild findings, so that good clinical tolerability is expected. Collectively, the preclinical data support first in human (FiH) phase I testing of therapeutic potential. A FiH trial with BAY 2965501 in patients with advanced solid tumors including NSCLC, gastric/GEJ AdCa, ccRCC, and melanoma patients, is currently enrolling patients (NCT05614102). This study will evaluate the safety, tolerability, maximum tolerated or administered dose, pharmacokinetics, pharmacodynamics, and tumor response profile of BAY 2965501. Citation Format: Rienk Offringa, Catherine Olesch, Frederik Cichon, Mareike Grees, Norbert Schmees, Ulrike Roehn, Florian Prinz, Judith Guenther, Detlef Stoeckigt, Michael Erkelenz, Thi Thanh Uyen Nguyen, Ulf Boemer, Nicolas Werbeck, Marc Kunze, Kirstin Petersen, Dennis Kirchhoff. BAY 2965501: A highly selective DGK- ζ inhibitor for cancer immuno-therapy with first-in-class potential [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr ND04.