Early Pharmacodynamic Changes Measured Using RNA Sequencing of Peripheral Blood from Patients in a Phase I Study with Mitazalimab, a Potent CD40 Agonistic Monoclonal Antibody

CD40-targeting therapies can enhance the dendritic cell priming of tumor-specific T cells and repolarize intratumoral macrophages to alleviate the tumoral immunosuppressive environment and remodel the extracellular matrix. Mitazalimab is a potent agonistic CD40 monoclonal IgG1 antibody currently under clinical development. This study used RNA sequencing of blood samples from a subset of patients from a Phase I trial with mitazalimab (NCT02829099) to assess peripheral pharmacodynamic activity. We found that mitazalimab induced transient peripheral transcriptomic alterations (at 600 µg/kg and 900 µg/kg dose administered intravenously), which mainly were attributed to immune activation. In particular, the transcriptomic alterations showed a reduction in effector cells (e.g., CD8+ T cells and natural killer cells) and B cells peripherally with the remaining cells (e.g., dendritic cells, monocytes, B cells, and natural killer cells) showing transcription profiles consistent with activation. Lastly, distinct patient subgroups based on the pattern of transcriptomic alterations could be identified. In summary, the data presented herein reinforce the anticipated mode of action of mitazalimab and support its ongoing clinical development.

Initial findings from a first-in-human, multicenter, open-label study of ATOR-1017, a 4-1BB antibody, in patients with advanced solid malignancies

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Background: ATOR-1017 is a human agonist Fcγ-receptor cross-linking dependent IgG4 antibody targeting the co-stimulatory receptor 4-1BB (CD137). ATOR-1017 activates T cells and natural killer cells in the tumor environment, leading to immune-mediated tumor cell killing. Methods: In this first-in-human, dose escalation, multicenter, phase 1 study (NCT04144842), adult patients with solid tumors refractory to standard therapy were enrolled in single patient cohorts for doses up to 40 mg, and thereafter in cohorts of 3-6 patients, to receive ATOR-1017 in a 21-day cycle. Intra-patient dose escalation of ATOR-1017 is allowed depending on the occurrence of Dose-Limiting Toxicities (DLTs) during cycle 1. ATOR-1017 is administered intravenously as monotherapy every three weeks until unacceptable toxicity, progressive disease, or withdrawal of consent. The primary objectives of the study are to determine the maximum tolerated dose, assess adverse events (AEs), evaluate DLTs, and to determine the recommended phase 2 dose. Secondary objectives include pharmacokinetics (PK), immunogenicity, and clinical efficacy, assessed with CT scans using Immune Response Evaluation Criteria in Solid Tumors (iRECIST). Exploratory objectives include assessment of pharmacodynamic (PD) biomarkers. Results: 22 patients (18 females), median age 55 years (34-76) with solid tumors, previously treated with median of 4 (0-6) lines of chemotherapy and/or 2 (0-3) lines of immunotherapy, were included and received at least one cycle ATOR-1017. Nine dose levels have been evaluated; 0.38 mg, 1.5 mg, 5 mg, 15 mg; 40 mg, 100 mg, 200 mg, 360 mg, and 600 mg and dose escalation is ongoing. Treatment-related (TRAEs) were reported in 12 out of 22 patients (54.5%); most common (≥10%) were fatigue (13.6%) and neutropenia (13.6%). Five patients experienced a grade 3-4 TRAE; neutropenia (n = 2), febrile neutropenia (n = 1), chest pain (n = 1), increased liver enzymes (n = 1) and leukopenia/thrombocytopenia (n = 1). No patients discontinued due to TRAEs, no DLTs were observed, and the maximum tolerated dose has not been reached. The median time for patients in the study was 12 weeks (range 4-67). As per data cut-off, January 18, 2022, four patients remained on treatment and 18 patients had discontinued treatment. The reasons for discontinuation include confirmed disease progression (n = 10), clinical deterioration (n = 4), withdrawal of consent (n = 1), death due to disease progression (n = 3). Preliminary PK data showed dose-proportional kinetics. Dose-dependent increase in PD biomarkers demonstrated target-mediated biological activity and proof-of-mechanism. The best response was stable disease observed in a total of 10 patients (45%). Conclusions: ATOR-1017 is safe and well-tolerated at doses up to 600 mg and has shown biologic activity. No DLTs have been reported so far and dose escalation continues. Clinical trial information: NCT04144842.

Mitazalimab in combination with mFOLFIRINOX in patients with metastatic pancreatic ductal adenocarcinoma (PDAC): Safety data from part of the OPTIMIZE-1 study

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Background: Mitazalimab is a human CD40 agonistic IgG1antibody being developed for cancer immunotherapy. Targeting CD40 kickstarts the cancer immunity cycle by licensing DCs leading to tumor-specific T cell priming and activation. Furthermore, in PDAC CD40 agonists on myeloid cells promote degradation of the desmoplastic tumor stroma, improving influx of T cells and chemotherapeutic agents into the tumor. Mitazalimab has shown to be safe and well tolerated (at doses up to 1200 μg/kg), with signs of clinical activity in solid tumors in a Phase I study (NCT02829099). Most drug related adverse events (AE) were grade 1 or 2. Methods: OPTIMIZE-1 (NCT04888312) is a Phase 1b/2, open-label, multicenter study designed to evaluate safety, tolerability, and efficacy of mitazalimab in combination with mFOLFIRINOX in adults diagnosed with previously untreated metastatic PDAC. In the first 21-day treatment cycle (Dose Limiting Toxicity (DLT) assessment period), mitazalimab is administered intravenously on day 1 and 10 and mFOLFIRINOX infusion starts on day 8. In the second and subsequent cycles, treatment follows a 14-day cycle schedule where mitazalimab is administered 2 days after mFOLFIRINOX. The primary objective of the first part of the study (Phase 1b) is to determine the recommended Phase 2 Dose (RP2D) of mitazalimab in combination with mFOLFIRINOX. Mitazalimab will be escalated from 450 µg/kg to 900 µg/kg following a Bayesian optimal interval design with at least 3 patients enrolled per dose level. A minimum of 6 patients will be evaluated at the RP2D. In Part 2 of the study, mitazalimab at the RP2D will be administered in combination with mFOLFIRINOX. The primary endpoint is RECIST-defined overall response rate. Progression-free survival and overall survival will be assessed as secondary endpoints. Here we report data from the Phase 1b (dose escalation) part of this study. Results: Five patients with histologically confirmed, previously untreated metastatic PDAC were treated at the 450 µg/kg dose level. Key baseline characteristics included: 2 female, 3 male; median age 65 (range 60-68); ECOG score of 0 or 1; median time since primary diagnosis 13 days (range 7-82). Treatment related AEs were only grade 1 or 2 (reported in 4 of 5 patients). Treatment related AEs occurring in > 1 patient were fever, muscle pain and nausea. No DLTs were reported. No patients required dose interruption/reduction with mitazalimab or mFOLFIRINOX. Two patients discontinued treatment due to disease progression and three remain on study. The study continues and patients are currently being enrolled at the 900 µg/kg mitazalimab dose in combination with mFOLFIRINOX. Conclusions: Mitazalimab at 450 µg/kg dose combined with mFOLFIRINOX is safe and well tolerated. Enrollment at the 900 µg/kg dose is ongoing for this Phase 1b/2 study. Updated data from part 1 of the study will be presented. Clinical trial information: NCT04888312.

Long-term analyses from L-MIND, a phase II study of tafasitamab (MOR208) combined with lenalidomide (LEN) in patients with relapsed or refractory diffuse large B-cell lymphoma (R/R DLBCL)

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Background: L-MIND (NCT02399085) is an ongoing, open-label, Phase II study of tafasitamab (MOR208), an Fc-modified, humanized, anti-CD19 monoclonal antibody, plus LEN in ASCT-ineligible patients (pts) with R/R DLBCL. Primary analyses and 2-year efficacy results were previously presented; we report an updated efficacy analysis with ≥35 months follow up (cut-off: October 30, 2020). Methods: Pts were aged ≥18 years with ASCT-ineligible R/R DLBCL, had 1–3 prior systemic therapies (Tx), including ≥1 CD20-targeting regimen, with an ECOG status of 0–2. Pts received 28-day cycles (C) of tafasitamab (12 mg/kg IV), once weekly during C1–3, with a loading dose on Day 4 of C1, then every 2 weeks (Q2W) during C4–12. LEN (25 mg PO) was administered on Days 1–21 of C1–12. After C12, progression-free pts received tafasitamab Q2W until disease progression. The primary endpoint was objective response rate (ORR), assessed by IRC. Secondary endpoints included duration of response (DoR), progression-free survival (PFS) and overall survival (OS). Results: Eighty of 81 enrolled pts received tafasitamab + LEN and were included in the full analysis set (1 prior Tx, n=40; 2+ prior Tx, n=40). At data cut-off, the overall ORR was 57.5% (n=46/80), including complete response (CR) in 40% of pts (n=32/80) and partial response (PR) in 17.5% of pts (n=14/80) (Table). Kaplan-Meier estimates: median DoR=43.9 months (95% CI: 26.1–not reached [NR]), and NR in pts who achieved a CR (95% CI: 43.9–NR); median PFS=11.6 months (95% CI: 6.3–45.7), with median follow-up 33.9 months; median OS=33.5 months (95% CI: 18.3–NR), with median follow-up 42.7 months. There were no unexpected toxicities or new safety signals. Conclusions: Combination Tx with tafasitamab + LEN followed by tafasitamab monotherapy provided durable responses in pts with R/R DLBCL not eligible for ASCT, with a manageable safety profile. These long-term data indicate the potential of tafasitamab + LEN followed by extended tafasitamab monotherapy in achieving prolonged remission and survival benefit in this patient population, especially at first relapse. Clinical trial information: NCT02399085. [Table: see text]

RE-MIND study: A propensity score-based 1:1 matched comparison of tafasitamab + lenalidomide (L-MIND) versus lenalidomide monotherapy (real-world data) in transplant-ineligible patients with relapsed/refractory (R/R) diffuse large B-cell lymphoma (DLBCL)

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Background: Patients with R/R DLBCL ineligible for autologous stem cell transplant (ASCT) have a poor prognosis. In these patients, tafasitamab (anti-CD19 antibody) plus lenalidomide (LEN) has shown encouraging results in the open-label, single-arm, phase II L-MIND study (n = 81; NCT02399085). To evaluate the contribution of tafasitamab to the activity of this doublet, we conducted a global, real-world study of patients treated with LEN monotherapy (RE-MIND; NCT04150328). Here we present the primary analysis of a 1:1 patient-level matched comparison between the L-MIND and RE-MIND cohorts. Methods: Patients treated with LEN monotherapy for R/R DLBCL were enrolled in the observational, retrospective RE-MIND cohort. As in L-MIND, patients had 1–3 prior systemic therapies, including ≥1 CD20-targeting regimen; were aged ≥18 years; and were not eligible for ASCT. A 1:1 estimated propensity score (ePS) matching methodology ensured balancing of nine pre-specified baseline covariates. The primary analysis set, Matched Analysis Set 25 (MAS25), included patients who received a LEN starting dose of 25 mg/day. The primary endpoint was investigator-assessed best objective response rate (ORR). Key secondary endpoints included overall survival (OS) and complete response (CR) rate. Results: 490 patients were enrolled in RE-MIND across 58 centers in the US and Europe, of which 140 fulfilled the ePS matching criteria. The MAS25 included 76 patients each from the two cohorts. Baseline characteristics between cohorts were comparable. The primary endpoint was met with a significantly better ORR of 67.1% (95% CI: 55.4–77.5) for the L-MIND cohort versus 34.2% (95% CI: 23.7–46.0) for the RE-MIND cohort (odds ratio 3.89; 95% CI: 1.90–8.14; p < 0.0001). The CR rate was 39.5% (95% CI: 28.4–51.4) in the L-MIND cohort and 13.2% (95% CI: 6.5–22.9) in the RE-MIND cohort. A significant difference in OS favored the L-MIND cohort (HR = 0.499; 95% CI: 0.317–0.785). ORR and CR outcomes in the RE-MIND cohort were similar to the published literature for LEN monotherapy in R/R DLBCL. Conclusions: Significantly better ORR, CR and OS indicate potential synergistic effects of the tafasitamab + LEN combination in ASCT-ineligible R/R DLBCL. ePS-based 1:1 matching allows robust estimation of the treatment effect of tafasitamab when added to LEN. RE-MIND demonstrates the utility of real-world data in interpreting non-randomized trials. Clinical trial information: NCT04150328 .

Update of the single-arm phase II L-MIND study of MOR208 + lenalidomide (LEN) in relapsed/refractory diffuse large B-cell lymphoma (R-R DLBCL): Response rates in patient subgroups with poor prognosis

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Background: MOR208, an Fc-enhanced, humanized, anti-CD19 monoclonal antibody has shown single agent activity in patients (pts) with R-R DLBCL and encouraging activity when combined with LEN in the phase II L-MIND study. Here we report an update with primary endpoint and subgroup analyses (cut off June 5, 2018). Methods: Key inclusion criteria were adequate organ function, ≤3 prior lines of therapy, including ≥1 anti-CD20 therapy, and ineligibility for stem cell transplantation. Treatment comprised up to 12, 28-day (d) cycles (C) of MOR208, 12 mg/kg IV, q1w C1–3 (loading dose on d4 of C1), and q2w C4–12 + LEN 25 mg PO d1–21, C1–12. Pts progression-free after 12 C received MOR208 q2w until progression. The primary endpoint was independent review committee (IRC)-assessed ORR as per Cheson 2007 criteria. Results: Recruitment is complete (N = 81): median age 72 years (range 41–87), median of 2 prior therapies, 19 (23%) of pts had early relapse (≤12 months [mo] from diagnosis), 32 (40%) were rituximab (RTX) refractory (no response to or progression during or within 6 mo of a prior RTX therapy), 34 (42%) were refractory to their last therapy, 21/40 (26%/49%) pts had non-germinal center B cell-like (GCB)- / GCB-DLBCL, and 42 (52%) had an International Prognostic Index (IPI) of 3–5. MOR208 + LEN therapy was well tolerated; 72% of pts stayed on a LEN dose of ≥20 mg/day. Treatment-related serious adverse events, mainly infections (10%) or neutropenic fever (5%), occurred in 17% of pts. Investigator (INV)-assessed complete response (CR) and partial response rates were 33% and 25%, respectively, giving an ORR of 58%, comparable to the IRC assessment (ORR 54%; CR 32%). ORR was 46% in pts with ≥2 prior therapies, 59%/56% in rituximab- / last treatment-refractory pts, 58% in early relapse pts, 57% in pts with a baseline IPI of 3–5, and 71% in pts with non-GCB- vs 53% with GCB-DLBCL. INV-assessed median PFS and OS (ITT analysis) were 16.2 mo (95% CI: 6.3–NR) and not reached (95% CI: 18.6–NR), respectively. Conclusions: MOR208 + LEN shows encouraging activity including a durable PFS in R-R DLBCL, and in pt subgroups with poor prognosis. Clinical trial information: NCT02399085.

L-mind: MOR208 combined with lenalidomide (LEN) in patients with relapsed or refractory diffuse large b-cell lymphoma (R-R DLBCL)—A single-arm phase II study

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Background: The Fc-enhanced CD19 antibody MOR208 and the immunomodulatory drug LEN have demonstrated single agent activity in patients (pts) with R-R DLBCL. MOR208 and LEN have shown synergy in vitro and in vivo in preclinical lymphoma models. This ongoing phase II study assesses the safety and efficacy of MOR208 + LEN in pts with R-R DLBCL. Methods: Pts >18 years old with R-R DLBCL, ECOG 0–2, adequate organ function, having previously received ≥1 but not more than 3 prior therapies, including ≥1 CD20-targeting regimen and who are not candidates for autologous stem cell transplant (ASCT), are eligible. Treatment comprises up to 12, 28-day (d) cycles (C) of MOR208 12 mg/kg IV, weekly during C1–3 (loading dose d4 of C1); every second week C4–12 + LEN 25 mg po d1–21, C1–12. Pts progression-free after 12 cycles receive up to 12 additional cycles of MOR208 (every second week). The primary endpoint is the overall response rate (ORR) by central radiology assessment. Secondary endpoints include disease control, duration of response, progression-free and overall survival, safety, and response by cell of origin and other biomarkers. A preplanned safety evaluation was undertaken. Results: 31 of 80 planned pts were enrolled prior to data cutoff (3 January 2017). Median age was 74 years (range 47–82); 45% of pts received ≥2 prior lines of therapy; 23% had rituximab refractory disease; 74% had Ann Arbor stage ≥III disease; 65% had elevated lactate dehydrogenase level, and 52% had a poor revised International Prognostic Index (3-5). The most common treatment-emergent adverse events (any grade/grade ≥3 [% pts]) were neutropenia (39/26), anemia (23/0) thrombocytopenia (16/6), infections (26/10) diarrhea (13/0), pyrexia (13/0), and rashes (13/6). Of 26 response evaluable pts (median follow-up 3.3 months), ORR (investigator assessed) was 58% (15 pts), with 7 (27%) complete responses. Median time to response was 1.8 months. Conclusions: The combination of MOR208 + LEN is well tolerated and shows promising activity in pts with R-R DLBCL. Accrual and follow-up of pts is ongoing, as are cell of origin and other biomarker analyses. Clinical trial information: NCT02399085.

Protective effect of Tinospora cordifolia, Phyllanthus emblica and their combination against antitubercular drugs induced hepatic damage: an experimental study

This study investigated the hepatoprotective effect of two Indian medicinal plants Tinospora cordifolia (Tc), Phyllanthus emblica (Pe), and their combination, in a rat model of isoniazid, rifampicin and pyrazinamide induced hepatic damage. Hepatic damage was assessed using a composite score assigned to histopathological findings of degeneration, necrosis and fibrosis. The antituberculosis treatment (ATT), when given for 90 days, induced significant degeneration and necrosis (score: 7.5; p < 0.01 vs vehicle) associated with morphological changes. However, no change was found in the serum bilirubin and liver enzymes. Co-administration of silymarin (positive control, 50 mg/kg) with ATT protected against necrosis (score: 1.5; p < 0.001 vs ATT). Tc (100 mg/kg) showed a reduction in liver damage (score: 6.5), which was not statistically significant. On the other hand, Pe (300 mg/kg) prevented the necrotic changes to a significant extent (grade 1.0; p < 0.05; score [corrected] 5.5). Combination of Tc and Pe in their therapeutic doses (1:3) significantly prevented the necrosis (score: 3.5; p < 0.001 vs ATT). Similar effects were seen even when the doses were halved and were comparable to the silymarin group. Thus, this study proves the synergistic protective effects exerted by the combination of Tc and Pe when co-administered with ATT.