berzosertib (M6620)

Across cohorts, only SDH-mutant GIST patients experienced prolonged disease control. Despite evidence of target engagement, patients enrolled to all other cohorts had short PFS, suggesting rapid adaptation to ATR inhibitor monotherapy. Among these patients, those with tumors expressing SLFN11 during berzosertib exposure derived the most clinical benefit.

Herein, we describe recent case examples of model-informed Asia-inclusive global clinical development in the EMD Serono portfolio, as applied to the ataxia telangiectasia and Rad3-related inhibitors, tuvusertib and berzosertib (oncology), the toll-like receptor 7/8 antagonist, enpatoran (autoimmune diseases), the mesenchymal-epithelial transition factor inhibitor tepotinib (oncology), and the antimetabolite cladribine (neuroimmunological disease). Through these case studies, we illustrate pragmatic approaches to ethnic sensitivity assessments and the application of a model-informed drug development toolkit including population pharmacokinetic/pharmacodynamic modeling and pharmacometric disease progression modeling and simulation to enable early conduct of Asia-inclusive MRCTs. These examples demonstrate the value of a Totality of Evidence approach where every patient's data matter for de-risking ethnic sensitivity to inter-population variations in drug- and disease-related intrinsic and extrinsic factors, enabling inclusive global development strategies and timely evidence generation for characterizing benefit/risk of the proposed dosage in Asian populations.

P1, N=15, Active, not recruiting, National Cancer Institute (NCI) | Trial completion date: Sep 2024 --> Sep 2025

The toxic and immunogenic effects of the smKI AZD0156 (ATMi) and VE-822 (ATRi) in combination with a hypo-fractionated scheme of 2x5Gy RT on HPV-negative (HSC4, Cal-33) and HPV-positive (UM-SCC-47, UD-SCC-2) HNSCC cell lines were analyzed as follows: cell death (necrosis, apoptosis; detected by AnxV/PI), expression of immunostimulatory (ICOS-L, OX40-L, TNFSFR9, CD70) and immunosuppressive (PD-L1, PD-L2, HVEM) checkpoint marker using flow cytometry; the release of cytokines using multiplex ELISA and the gene expression of Cal-33 on mRNA level 48 h post-RT. This includes pro-inflammatory signaling induced by RT + ATRi but also anti-inflammatory signals. These findings were confirmed by RNAseq analysis, which further highlighted the immune-suppressive nature of RT + ATMi.

Co-treatment with ATR inhibitor (VX970) and BER inhibitor (methoxyamine) at clinically relevant doses synergistically enhanced DNA damage and reduced cell proliferation in PDAC cells. The study provides mechanistic insights into the regulation of TRCs in PDAC by the BER pathway, which has biologic and therapeutic implications.

This study shows that targeting ATR up-regulates major histocompatibility class I expression in preclinical models and SCLC clinical samples collected from a first-in-class clinical trial of ATR inhibitor, berzosertib, with topotecan in patients with relapsed SCLC. Targeting ATR represents a transformative vulnerability of SCLC and is a complementary strategy to induce STING-interferon signaling-mediated immunogenicity in SCLC.

P1/2, N=25, Active, not recruiting, M.D. Anderson Cancer Center | Trial completion date: Sep 2024 --> Dec 2025 | Trial primary completion date: Sep 2024 --> Dec 2025

P1/2, N=120, Recruiting, National Cancer Institute (NCI) | Suspended --> Recruiting | N=13 --> 120

Loss of FAM110C expression sensitizes PDAC cells to VE-822 (an ATR inhibitor) and MK-8776 (a CHK1 inhibitor). FAM110C methylation is a potential diagnostic and prognostic marker in PDAC, and its epigenetic silencing sensitizes PDAC cells to ATR/CHK1 inhibitors.

We also show that SCAF1 deficiency partly rescues RAD51 loading in cells lacking the BRCA1 tumour suppressor. Taken together these data reveal potential new ATR biomarkers and new genome maintenance factors.

P1/2, N=13, Suspended, National Cancer Institute (NCI) | N=120 --> 13 | Recruiting --> Suspended

P1/2, N=120, Recruiting, National Cancer Institute (NCI) | N=85 --> 120

P2, N=87, Active, not recruiting, National Cancer Institute (NCI) | Trial completion date: Apr 2024 --> May 2025

P1/2, N=120, Recruiting, National Cancer Institute (NCI) | N=75 --> 120

The results of this follow-up analysis continue to support the promise of combined gemcitabine/ATRi therapy in platinum resistant ovarian cancer, an active area of investigation with several ongoing clinical trials.

P1/2, N=12, Active, not recruiting, National Cancer Institute (NCI) | N=106 --> 12 | Trial completion date: Aug 2024 --> Apr 2025 | Trial primary completion date: Aug 2024 --> Mar 2024

The simultaneous treatment of resistant colorectal cancer cells with 5-FU and ATR inhibitor, VE-822, was demonstrated to be effective in reversing drug resistance and potentiating 5-FU mediated anticancer effects via targeting DNA damage.

Patients who had better outcomes were those who were diagnosed at an early stage and received treatment with surgery or radiation and androgen deprivation therapy (ADT). There was one case with an exceptional outcome that included a treatment regimen of M6620 and chemotherapy.

These data exploit EWS-FLI1 driven alterations in cell context to broaden the therapeutic window of berzosertib and cisplatin to establish a promising combination therapy and a novel in vivo schedule.

P1, N=43, Active, not recruiting, National Cancer Institute (NCI) | Trial completion date: Dec 2023 --> Mar 2025

As single agent, M1774 suppressed cancer cell viability at nanomolar concentrations, showing greater activity than ceralasertib and berzosertib, but less potency than gartisertib and elimusertib in the small-cell lung cancer H146, H82, and DMS114 cell lines. Low dose of M1774 was found highly synergistic with a broad spectrum of clinical DDAs including TOP1 inhibitors (SN-38/irinotecan, topotecan, exatecan, and exatecan), the TOP2 inhibitor etoposide, cisplatin, the RNA polymerase II inhibitor lurbinectedin, and the PARP inhibitor talazoparib in various models including cancer cell lines, patient-derived organoids, and mouse xenograft models. Furthermore, we demonstrate that M1774 reverses chemoresistance to anticancer DDAs in cancer cells lacking SLFN11 expression, suggesting that SLFN11 can be utilized for patient selection in upcoming clinical trials.

P2, N=81, Active, not recruiting, National Cancer Institute (NCI) | Trial completion date: Sep 2023 --> Jan 2025

We found a subpopulation of glioma sphere-forming cells (GSCs) with substantial synergism with temozolomide (TMZ) using a panel of 3 clinical-grade ataxia-telangiectasia- and Rad3-related kinase inhibitors (ATRis), (elimusertib, berzosertib, and ceralasertib). This research provides a rationale for selectively targeting MGMT-methylated cells using ATRis and TMZ combination. Overall, we believe that MGMT methylation status in GBM could serve as a robust biomarker for patient selection for ATRi combined with TMZ.

P2, N=130, Active, not recruiting, National Cancer Institute (NCI) | Trial completion date: Dec 2023 --> Dec 2024 | Trial primary completion date: Dec 2023 --> Dec 2024

P1/2, N=75, Recruiting, National Cancer Institute (NCI) | Trial completion date: Dec 2026 --> Dec 2027 | Trial primary completion date: Aug 2025 --> Aug 2026

Loss of RASSF1A expression sensitized esophageal cancer cell lines to ataxia telangiectasia mutated and rad3-related (ATR) inhibitor (VE-822) both in vitro and in vivo. RASSF1A methylation is a synthetic lethal marker for ATR inhibitors.

P1, N=66, Active, not recruiting, National Cancer Institute (NCI) | Trial completion date: Apr 2024 --> Dec 2024 | Trial primary completion date: Apr 2024 --> Mar 2023

P1, N=45, Active, not recruiting, National Cancer Institute (NCI) | Trial completion date: Sep 2023 --> Dec 2023 | Trial primary completion date: Sep 2023 --> Dec 2023

P1/2, N=106, Active, not recruiting, National Cancer Institute (NCI) | Phase classification: P2 --> P1/2

P1, N=31, Active, not recruiting, National Cancer Institute (NCI) | Trial completion date: Nov 2023 --> Nov 2024 | Trial primary completion date: Nov 2023 --> Nov 2024

Materials and methodsIn the customized shRNA library screen, 2009 shRNAs developed to target 671 genes were pool-cloned into a retroviral vector allowing doxycycline-inducible expression to generate a plasmid shRNA library (Antonova et al...We validated, genetically and pharmacologically, DNMT1 and ATR using several AML1/ETO-positive (SKNO-1, Kasumi-1) and AML1/ETO-negative cell lines (OCI-AML3, HL60) with median IC50 for decitabine 74 nM (range 44-219), azacytidine 146 nM (range 14-267), berzosertib 219 nM (range 16-460) and ceralasertib 85 nM (range 42-328)...Some of these epigenetic regulators, such as DNMT1 and ATR, are susceptible to pharmacological inhibition by small molecules showing promising preclinical and clinical efficacy, and confirmation studies (Baeten et al. , ASH meeting 2022) appear warranted.

P1, N=42, Active, not recruiting, National Cancer Institute (NCI) | Phase classification: P1b --> P1 | Trial completion date: Nov 2023 --> Nov 2024 | Trial primary completion date: Nov 2023 --> Nov 2024

Berzosertib displays a cytotoxic effect in HNSCC at clinically relevant doses. Further evaluation of combination treatment with irradiation and cisplatin is strongly recommended in HNSCC patients as it may hold the potential to overcome treatment resistance, reduce treatment doses and thus mitigate adverse events.

Preliminary results from in vivo experiments using p53 deficient patient derived xenografts indicate that the combination of Orludodstat and Berzosertib is well tolerated, while significantly delaying leukemic growth (Figure 1 B). ConclusionTogether, our findings suggest that the combined targeting of de novo pyrimidine synthesis and ATR signaling may present a specific and non-genotoxic vulnerability for TP53 aberrant ALL.

P1, N=15, Active, not recruiting, National Cancer Institute (NCI) | Trial completion date: Feb 2024 --> Sep 2024

However, the combination treatment significantly improved OS. ClinicalTrials.gov Identifier: NCT03896503.

Inhibition of the ATR-Chk1 pathway by targeting ATR kinase with VX970 sensitizes CRC to radiotherapy in vitro and in vivo. Our findings support that ATR inhibition by VX970 is a promising new approach to improve the therapeutic ratio of radiotherapy for patients with CRC and warrants further clinical testing.

P2, N=106, Active, not recruiting, National Cancer Institute (NCI) | Recruiting --> Active, not recruiting

P2, N=72, Recruiting, Institut Bergonié | Trial completion date: Oct 2025 --> Apr 2026 | Trial primary completion date: Feb 2024 --> Oct 2024

P1/2, N=25, Active, not recruiting, M.D. Anderson Cancer Center | Recruiting --> Active, not recruiting | N=36 --> 25

The DNA-damaging drugs, topotecan, trabectedin, and temozolomide were combined with varied inhibitors of DNA damage response enzymes including PARP (olaparib or talazoparib), ATM (ataxia telangiectasia mutated; AZD-1390), ATR (ataxia telangiectasia and Rad3-related protein; berzosertib or elimusertib), and DNA-PK (DNA-dependent protein kinase; nedisertib or VX-984). The potentiation of DNA-damaging drugs by pharmacologic modulation of DNA repair pathways was assessed in multicellular tumor spheroids. Although most combinations demonstrated additive cytotoxicity, synergistic cytotoxicity was observed for several drug combinations.

P2, N=106, Recruiting, National Cancer Institute (NCI) | Trial completion date: Aug 2023 --> Aug 2024 | Trial primary completion date: Aug 2023 --> Aug 2024