BACKGROUND: Ovarian cancer is a primary cause of cancer-related death in women. At the time of diagnosis, the majority of ovarian malignancies had metastasized. It is believed that cancer stem cells (CSCs) and immune evasion play a crucial role in the metastatic process. The objective of this study was to describe the expression profiles of cluster of differentiation (CD)133, CD47, and programmed death ligand 1 (PD-L1) in high-grade serous ovarian cancer (HGSC) as commonly utilized markers for CSCs and immune evasion.
METHODS: Using an immunohistochemical procedure, 51 HGSC tissue samples were stained with anti-CD133, anti-CD47, and anti-PDL1 antibodies. The samples contained 31 HGSC with metastases and 20 HGSC absent metastases. The expression of CD133, CD47, and PD-L1 was compared between groups.
RESULTS: Strong expression of CD133 and CD47 was seen in 52% and 66% of tissue samples, respectively. Twenty of the thirty-one patients with metastases had a significant level of CD133 expression, with a p-value of 0.039. CD47 expression was increased in 26 of 31 samples with metastatic disease. A 62.7 percent of samples were negative for PD-L1 expression, significantly inversely correlated with HGSC metastatic disease (p=0.023). Although there was no significant association between CD133, CD47, or PD-L1 expression and age, Tumor Infiltrating Lymphocytes demonstrated a significantly varied relationship.
CONCLUSIONS: Our findings suggested that expression of CD133, CD47, and PD-L1 may have dynamically increased as the primary lesion progressed to the metastatic lesion, implying that these proteins may be involved in the progression of high-grade serous ovarian cancer from the primary to the metastatic stage.

UNASSIGNED: Unlike B-cell acute lymphoblastic leukemia/lymphoma (ALL/LBL), there have been few therapeutic advances in T-cell ALL (T-ALL)/LBL, an aggressive ALL/LBL subtype.
UNASSIGNED: To perform a focused tissue array study to elucidate tumor markers of therapeutic potential in T-ALL/LBL.
UNASSIGNED: Using immunohistochemistry, we evaluated expression of leukemic antigens of interest, specifically CC-chemokine receptor 4 (CCR4), among others, on available remnant diagnostic material, including tumor tissue slides obtained from formalin-fixed, paraffin-embedded preserved tissues.
UNASSIGNED: Our analysis identified, for the first time, expression of CCR4 in T-ALL/LBL in 11 of 27 cases (40.7%) and confirmed common expression of BCL2, CD38, and CD47, as reported previously. We also identified the expression of CD123 in 4 of 26 cases (15.4%), whereas BCL6 and PDL1 were expressed in a small number of T-ALL/LBL cases. The potential novel target CCR4 was significantly more common in the Pre/Pro-T immunophenotypic subtype, 6 of 9 (66.7%, P = .01). No additional differences in clinical and epidemiologic variables were noted among positive or negative CCR4 cases.
UNASSIGNED: These findings support preclinical and clinical testing of therapies targeting CCR4, CD47, BCL2, CD38, and CD123 in T-ALL/LBL, and may help guide the development of targeted clinical trials in T-ALL/LBL, a rare disease in urgent need of novel therapies.

Magrolimab is a monoclonal antibody that blocks CD47, a \'do not eat me\' signal overexpressed on tumor cells. CD47 is overexpressed in multiple myeloma (MM), which contributes to its pathogenesis. Preclinical studies have shown that CD47 blockade induces macrophage activation, resulting in elimination of myeloma cells, and that there is synergy between magrolimab and certain anticancer therapies. These findings suggest that magrolimab-based combinations may have a therapeutic benefit in MM. This phase II study investigates magrolimab in combination with commonly used myeloma therapies in patients with relapsed/refractory MM and includes a safety run-in phase followed by a dose-expansion phase. Primary end points include the incidence of dose-limiting toxicities and adverse events (safety run-in) and the objective response rate (dose expansion).
Magrolimab is a therapy that blocks a ‘do not eat me’ signal overexpressed by certain cancers, including multiple myeloma (MM) cells. Studies have shown that blocking this signal leads to destruction of myeloma cells and that this cancer-killing effect may be increased by combining magrolimab with certain additional anticancer therapies. These findings suggest that magrolimab-based combinations may have a therapeutic benefit in MM. This study is investigating magrolimab in combination with commonly used myeloma therapies in patients with MM who have persistent disease despite prior treatment. Goals of the trial include assessing safety and response to treatment. Clinical Trial Registration: NCT04892446 (ClinicalTrials.gov).

BACKGROUND: Magrolimab is a monoclonal antibody blocking CD47, a \"don\'t eat me\" signal overexpressed on cancer cells, which leads to tumor phagocytosis and is synergistic with azacitidine. A high unmet need exists to build on current standard-of-care azacitidine in patients with HR MDS.
OBJECTIVE: Report final safety/tolerability and efficacy data.
METHODS: Ph1b trial of magrolimab+azacitidine (NCT03248479).
METHODS: 95 patients with untreated HR MDS (intermediate, high, or very-high risk per the Revised International Prognostic Scoring System [IPSS-R]).
METHODS: Magrolimab IV 1-mg/kg (priming) then 30-mg/kg ramp-up QW/Q2W (maintenance). Azacitidine 75 mg/m2 IV/SC days 1-7 (each 28-day cycle).
METHODS: Primary endpoints were safety/tolerability and complete remission (CR) rate.
RESULTS: Median age was 69y [range, 28-91y]). IPSS-R risk was intermediate, high, or very high in 27%, 52%, and 21% of patients, respectively. Therapy-related MDS, TP53 mutation, and poor-risk cytogenetics were reported in 22%, 26%, and 62% of patients, respectively. Median number of cycles was 6 (range, 1-27). The most common treatment-emergent adverse events (TEAEs) included constipation (68%), thrombocytopenia (55%), anemia (52%), neutropenia (47%), nausea (46%), and diarrhea (43%). The most common grade 3/4 TEAEs included anemia (47%), neutropenia (46%), thrombocytopenia (46%), and white blood cell count decreased (30%). Six patients discontinued treatment due to AEs. The 60-day mortality rate was 2%. Median hemoglobin change from baseline at first post dose sample was -0.7 g/dL (range, -3.1 to 2.4 g/dL). CR and objective response (OR) rates were 33% and 75%; 31% of OR-evaluable patients with baseline abnormal cytogenetics had cytogenetic CR. Median time to first OR, duration of CR, duration of OR, and progression-free survival were 1.9, 11.1, 9.8, and 11.6 months, respectively. 12- and 24-month overall survival (OS) rates were 75% and 52%, respectively; median OS was not reached with 17.1 months of follow-up. Favorable outcomes were observed in patients with TP53 mutation (n=25; CR rate, 40%; median OS, 16.3 months) and wild-type TP53 (n=61; CR rate, 31%; median OS, not reached).
CONCLUSIONS: Magrolimab+azacitidine was well tolerated, with promising efficacy in patients with untreated HR MDS, including those with TP53-mutated and -wild-type disease. A Ph3 trial of magrolimab/placebo+azacitidine (ENHANCE; NCT04313881) is ongoing.

BACKGROUND: Patients with newly diagnosed AML who are ineligible for intensive chemotherapy (IC) are incurable, despite progress with azacitidine + venetoclax, whereas patients with relapsed/refractory disease continue to have a poor prognosis. Furthermore, relapse remains frequent for patients in remission receiving oral azacitidine. Magrolimab is a blocking antibody against CD47, a \"don\'t eat me\" signal overexpressed on cancer cells. This blockade induces tumor phagocytosis and is synergistic with chemotherapy and hypomethylating agents. Magrolimab + azacitidine has demonstrated encouraging efficacy in newly diagnosed AML (objective response rate [ORR], 63%; complete remission [CR], 42%).
OBJECTIVE: To evaluate the safety/tolerability and efficacy of magrolimab combined with antileukemia therapies in patients with newly diagnosed or relapsed/refractory AML or with AML in maintenance post-IC.
METHODS: This open-label, multi-arm, multicenter study includes 3 safety run-ins with corresponding expansion cohorts (NCT04778410). Safety run-in cohorts will enroll 6 patients for 28 days to determine dose-limiting toxicities and the recommended phase 2 dose prior to enrollment of phase 2 cohorts.
METHODS: Patients must be aged ≥75 or 18-74 years with comorbidities precluding IC (cohort [C]1), have relapsed/primary refractory disease post-IC (C2), or have CR/CR with incomplete hematologic recovery and measurable residual disease (MRD) post-IC (C3).
METHODS: Patients will receive magrolimab + venetoclax + azacitidine (C1), magrolimab + mitoxantrone + etoposide + cytarabine (MEC; C2), or magrolimab + CC-486 (C3). In all cohorts, magrolimab will be administered intravenously with priming and ramp-up doses of 1 (day [D]1, D4), 15 (D8), and 30 mg/kg (D11, D15, then QW [x5], followed by Q2W). Azacitidine, venetoclax, MEC, and CC-486 will be administered per label indications. After completion of the safety run-ins, additional patients will be enrolled into the phase 2 study (C1, n=40; C2, n=30; C3, n=40). Study treatments will follow the dosing schedule until disease progression, unacceptable toxicity, or loss of clinical benefit (C1/C3) or for 2 to 3 cycles for MEC with a maximum 12 months of magrolimab (C2).
METHODS: Primary efficacy endpoints are CR rate (C1/C2) and MRD-negative CR rate (C3). Secondary endpoints include overall survival, ORR, and MRD negativity (C1/C2).

Tumour therapy has entered the era of immunotherapy. Monoclonal antibodies (mAb), immune checkpoint inhibitors, chimeric antigen receptor T-cell (CAR-T), cytokine-induced killer (CIK), tumour-infiltrating lymphocytes (TILs) and other cellular immunotherapies have become the focus of current research. The CD47/SIRPα target is becoming another popular tumour immunotherapy target following the PDCD1/CD247(PD1/PD-L1) checkpoint inhibitor. In recent years, a large number of CD47/SIRPα mAbs, fusion proteins, and CD47/SIRPα-based bispecific antibodies (BsAbs) are undergoing preclinical and clinical trials and have good curative effects in the treatment of haematological tumours and solid tumours. They bring new vitality and hope for the treatment of patients with advanced tumours. This review summarizes the research progress of CD47/SIRPα-based BsAbs with different targets for tumour treatment. There are 12 and 9 BsAbs in clinical trials and pre-clinical research, respectively. We report on the mechanism of 15 BsAb molecules with different target and analyse the efficacy and safety of preclinical and clinical trials, discuss the issues that may be faced in the development of CD47-based BsAbs, and dual-target molecules, and summarize their development prospects. This review provides a reference for the safety and effectiveness of BsAbs in clinical application and in the future development of antibodies.

UNASSIGNED: To study the effects of CD47-targted immunotherapy on the oral-gut microbiota of immune-competent mice.
UNASSIGNED: A peritoneal metastatic colon cancer model was constructed in immune-competent mice. Anti-CD47 monoclonal antibody was intraperitoneally administered to the mice in the treatment group, while PBS was administered to mice in the control group. Tumor growth was documented with small animal live imaging technology. 16S rRNA sequencing technology was used to analyze the composition and diversity of oral-gut microbiota.
UNASSIGNED: The alpha diversity of oral microbes in the anti-CD47 monoclonal antibody treatment group decreased, and the difference was statistically significant. There was no significant change in the alpha diversity of gut microbes. Differential species analysis showed significantly decreased abundance of Staphylococcus, Jeotgalicoccus, and Sporosarcina in the oral microbiota of mice in the treatment group compared to that of mice in the control group. The abundance of Bacteroides in the gut microbiota was significantly higher in the treatment group.
UNASSIGNED: CD47-targted immunotherapy has a rather significant impact on the diversity of oral microbiota in mice, but does not have significant impact on the species diversity of gut microbiota.

CC-90002 is an anti-CD47 antibody that inhibits CD47-SIRPα interaction and enables macrophage-mediated killing of tumor cells in hematological cancer cell lines. In this first clinical, phase 1, dose-escalation and -expansion study (CC-90002-AML-001; NCT02641002), we evaluated CC-90002 in patients with relapsed/refractory acute myeloid leukemia (AML) or high-risk myelodysplastic syndromes (MDS). CC-90002 was administered in escalating doses of 0.1-4.0 mg/kg, using a modified 3 + 3 design. Primary endpoints included dose-limiting toxicities (DLTs), non-tolerated dose (NTD), maximum tolerated dose (MTD), and recommended phase 2 dose. Secondary endpoints included preliminary efficacy, pharmacokinetics, and presence/frequency of anti-drug antibodies (ADAs). Between March 2016 and July 2018, 28 patients were enrolled (24 with AML and 4 with MDS) at 6 sites across the USA. As of July 18, 2018, all patients had discontinued, mainly due to death or progressive disease. The most common treatment-emergent adverse events were diarrhea (46.4%), thrombocytopenia (39.3%), febrile neutropenia (35.7%), and aspartate aminotransferase increase (35.7%). Four patients experienced DLTs (1 patient had grade 4 disseminated intravascular coagulation and grade 5 cerebral hemorrhage, 1 had grade 3 purpura, 1 had grade 4 congestive cardiac failure and grade 5 acute respiratory failure, and another had grade 5 sepsis). The NTD and MTD were not reached. No objective responses occurred. CC-90002 serum exposure was dose-dependent. ADAs were present across all doses, and the proportion of ADA-positive patients in cycle 1 increased over time. Despite no unexpected safety findings, the CC-90002-AML-001 study was discontinued in dose escalation for lack of monotherapy activity and evidence of ADAs. However, as other anti-CD47 agents in clinical trials are showing promising early results for AML and MDS, understanding preclinical and clinical differences between individual agents in this class will be of high importance.

BACKGROUND: Intravenous TTI-621 (SIRPα-IgG1 Fc) was previously shown to have activity in relapsed or refractory haematological malignancies. This phase 1 study evaluated the safety and activity of TTI-621 in patients with percutaneously accessible relapsed or refractory mycosis fungoides, Sézary syndrome, or solid tumours. Here we report the clinical and translational results among patients with mycosis fungoides or Sézary syndrome.
METHODS: This multicentre, open-label, phase 1 study was conducted at five academic health-care and research centres in the USA. Eligible patients were aged 18 years or older; had injectable, histologically or cytologically confirmed relapsed or refractory cutaneous T-cell lymphoma (CTCL) or solid tumours; Eastern Cooperative Oncology Group performance status of 2 or less; and adequate haematological, renal, hepatic, and cardiac function. TTI-621 was injected intralesionally in a sequential dose escalation (cohorts 1-5; single 1 mg, 3 mg, or 10 mg injection or three 10 mg injections weekly for 1 or 2 weeks) and in expansion cohorts (cohorts 6-9; 2 week induction at the maximum tolerated dose; weekly continuation was allowed). In cohort 6, patients were injected with TTI-621 in a single lesion and in cohort 7, they were injected in multiple lesions. In cohort 8, TTI-621 was combined with pembrolizumab 200 mg injections per product labels. In cohort 9, TTI-621 was combined with the standard labelled dose of subcutaneous pegylated interferon alpha-2a 90 μg. The primary endpoint was the incidence and severity of adverse events. The study is registered with ClinicalTrials.gov, NCT02890368, and was closed by the sponsor to focus on intravenous studies with TTI-621.
RESULTS: Between Jan 30, 2017, and March 31, 2020, 66 patients with mycosis fungoides, Sézary syndrome, other CTCL, or solid tumours were screened, 35 of whom with mycosis fungoides or Sézary syndrome were enrolled and received intralesional TTI-621 (escalation, n=13; expansion, n=22). No dose-limiting toxicities occurred; the maximum tolerated dose was not established. In the dose expansion cohorts, the maximally assessed regimen (10 mg thrice weekly for 2 weeks) was used. 25 (71%) patients had treatment-related adverse events; the most common (occurring in ≥10% of patients) were chills (in ten [29%] patients), injection site pain (nine [26%]), and fatigue (eight [23%]). No treatment-related adverse events were grade 3 or more or serious. There were no treatment-related deaths. Rapid responses (median 45 days, IQR 17-66) occurred independently of disease stage or injection frequency. 26 (90%) of 29 evaluable patients had decreased Composite Assessment of Index Lesion Severity (CAILS) scores; ten (34%) had a decrease in CAILS score of 50% or more (CAILS response). CAILS score reductions occurred in adjacent non-injected lesions in eight (80%) of ten patients with paired assessments and in distal non-injected lesions in one additional patient.
CONCLUSIONS: Intralesional TTI-621 was well tolerated and had activity in adjacent or distal non-injected lesions in patients with relapsed or refractory mycosis fungoides or Sézary syndrome, suggesting it has systemic and locoregional abscopal effects and potential as an immunotherapy for these conditions.
BACKGROUND: Trillium Therapeutics.

TTI-621 (SIRPα-IgG1 Fc) is a novel checkpoint inhibitor that activates antitumor activity by blocking the CD47 \"don\'t eat me\" signal. This first-in-human phase I study (NCT02663518) evaluated the safety and activity of TTI-621 in relapsed/refractory (R/R) hematologic malignancies.
Patients with R/R lymphoma received escalating weekly intravenous TTI-621 to determine the maximum tolerated dose (MTD). During expansion, patients with various malignancies received weekly single-agent TTI-621 at the MTD; TTI-621 was combined with rituximab in patients with B-cell non-Hodgkin lymphoma (B-NHL) or with nivolumab in patients with Hodgkin lymphoma. The primary endpoint was the incidence/severity of adverse events (AEs). Secondary endpoint included overall response rate (ORR).
Overall, 164 patients received TTI-621: 18 in escalation and 146 in expansion (rituximab combination, n = 35 and nivolumab combination, n = 4). On the basis of transient grade 4 thrombocytopenia, the MTD was determined as 0.2 mg/kg; 0.1 mg/kg was evaluated in combination cohorts. AEs included infusion-related reactions, thrombocytopenia, chills, and fatigue. Thrombocytopenia (20%, grade ≥3) was reversible between doses and not associated with bleeding. Transient thrombocytopenia that determined the initial MTD may not have been dose limiting. The ORR for all patients was 13%. The ORR was 29% (2/7) for diffuse large B-cell lymphoma (DLBCL) and 25% (8/32) for T-cell NHL (T-NHL) with TTI-621 monotherapy and was 21% (5/24) for DLBCL with TTI-621 plus rituximab. Further dose optimization is ongoing.
TTI-621 was well-tolerated and demonstrated activity as monotherapy in patients with R/R B-NHL and T-NHL and combined with rituximab in patients with R/R B-NHL.