CX-904 for Advanced Solid Cancers
Recruiting in Palo Alto (17 mi)
+4 other locations
Age: 18+
Sex: Any
Travel: May Be Covered
Time Reimbursement: Varies
Trial Phase: Phase 1
Recruiting
Sponsor: CytomX Therapeutics
Disqualifiers: Active malignancy, Autoimmune diseases, Myocarditis, others
No Placebo Group
Trial Summary
What is the purpose of this trial?This trial is testing CX-904, a new medicine that helps the immune system fight advanced cancers that can't be removed by surgery. It works by connecting immune cells to cancer cells, making it easier for the body to attack the cancer.
Will I have to stop taking my current medications?
The trial information does not specify whether you need to stop taking your current medications. It's best to discuss this with the trial coordinators or your doctor.
What data supports the effectiveness of the drug CX-904 for advanced solid cancers?
Research on similar treatments, like the Probody-drug conjugate CX-2029, shows promising results in targeting cancer cells while minimizing harm to normal cells. This approach has demonstrated effective tumor growth inhibition in preclinical models, suggesting potential for CX-904.
12345What safety data exists for CX-904 and related Probody therapeutics?
Probody therapeutics, like CX-904, are designed to be activated only in the tumor environment, which helps reduce side effects in normal tissues. Studies on similar Probody drugs have shown improved safety profiles compared to traditional treatments, with reduced off-target effects and better tolerability in preclinical models.
24567What makes the drug CX-904 unique for treating advanced solid cancers?
CX-904 is a novel treatment that uses a Probody therapeutic approach, which means it remains inactive until it reaches the tumor environment, reducing side effects on healthy tissues. This drug specifically targets EGFR (a protein often overexpressed in cancer cells) and engages T-cells (a type of immune cell) to attack the cancer, offering a more targeted and potentially safer treatment option compared to traditional therapies.
248910Eligibility Criteria
This trial is for adults with advanced solid tumors that can't be surgically removed and have spread. They should have tried standard treatments already, not have serious heart issues or autoimmune diseases, and agree to use effective birth control. Those with small, symptom-free brain metastases may join after special consideration.Inclusion Criteria
Adequate baseline laboratory values
I have small brain tumors (≤1 cm) that need treatment.
Patients of childbearing potential or those with partners of childbearing potential must agree to use a highly effective method of birth control from signing the ICF, and for a period of 30 days after the last dose of CX-904.
+4 more
Exclusion Criteria
I had cancer within the last 2 years, but it's considered cured and low risk of coming back.
Additional exclusion criteria may apply
Screening electrocardiogram demonstrating a mean QTcF value > 480 msec; a screening echocardiogram with left ventricular ejection fraction (LVEF) < 50%
+1 more
Trial Timeline
Screening
Participants are screened for eligibility to participate in the trial
2-4 weeks
Dose Escalation
Participants receive escalating doses of CX-904 to determine safety and tolerability
12 months
Follow-up
Participants are monitored for safety and effectiveness after treatment
30 months
Participant Groups
The study tests CX-904's safety and effectiveness in treating advanced solid tumors. It will assess how the body processes the drug (PK), its impact on the tumor (PD), tolerability at different doses, and any potential benefits in shrinking or controlling tumor growth.
1Treatment groups
Experimental Treatment
Group I: CX-904Experimental Treatment1 Intervention
Find a Clinic Near You
Research Locations NearbySelect from list below to view details:
Sarah Cannon Research Institute, LLCNashville, TN
Sarah Cannon Research Institute at HealthONEDenver, CO
Virginia Cancer SpecialistFairfax, VA
South Texas Accelerated Research Therapeutics, LLCSan Antonio, TX
More Trial Locations
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Who Is Running the Clinical Trial?
CytomX TherapeuticsLead Sponsor
References
Nanobody-based trispecific T cell engager (Nb-TriTE) enhances therapeutic efficacy by overcoming tumor-mediated immunosuppression. [2023]T cell engagers (TCEs) have been established as an emerging modality for hematologic malignancies, but solid tumors remain refractory. However, the upregulation of programmed cell death 1 (PD-1) is correlated with T cell dysfunction that confer tumor-mediated immunosuppression. Developing a novel nanobody-based trispecific T cell engager (Nb-TriTE) would be a potential strategy to improve therapeutic efficacy.
Nonclinical Efficacy and Safety of CX-2029, an Anti-CD71 Probody-Drug Conjugate. [2023]Probody therapeutics (Pb-Txs) are conditionally activated antibody-drug conjugates (ADCs) designed to remain inactive until proteolytically activated in the tumor microenvironment, enabling safer targeting of antigens expressed in both tumor and normal tissue. Previous attempts to target CD71, a highly expressed tumor antigen, have failed to establish an acceptable therapeutic window due to widespread normal tissue expression. This study evaluated whether a probody-drug conjugate targeting CD71 can demonstrate a favorable efficacy and tolerability profile in preclinical studies for the treatment of cancer. CX-2029, a Pb-Tx conjugated to maleimido-caproyl-valine-citrulline-p-aminobenzyloxycarbonyl-monomethyl auristatin E, was developed as a novel cancer therapeutic targeting CD71. Preclinical studies were performed to evaluate the efficacy and safety of this anti-CD71 PDC in patient-derived xenograft (PDX) mouse models and cynomolgus monkeys, respectively. CD71 expression was detected at high levels by IHC across a broad range of tumor and normal tissues. In vitro, the masked Pb-Tx form of the anti-CD71 PDC displayed a >50-fold reduced affinity for binding to CD71 on cells compared with protease-activated, unmasked anti-CD71 PDC. Potent in vivo tumor growth inhibition (stasis or regression) was observed in >80% of PDX models (28/34) at 3 or 6 mg/kg. Anti-CD71 PDC remained mostly masked (>80%) in circulation throughout dosing in cynomolgus monkeys at 2, 6, and 12 mg/kg and displayed a 10-fold improvement in tolerability compared with an anti-CD71 ADC, which was lethal. Preclinically, anti-CD71 PDC exhibits a highly efficacious and acceptable safety profile that demonstrates the utility of the Pb-Tx platform to target CD71, an otherwise undruggable target. These data support further clinical development of the anti-CD71 PDC CX-2029 as a novel cancer therapeutic.
First-in-Human Study of the Biodistribution and Pharmacokinetics of 89Zr-CX-072, a Novel Immunopet Tracer Based on an Anti-PD-L1 Probody. [2022]CX-072, a PD-L1-targeting Probody therapeutic, is engineered to be activated by tumor proteases that remove a masking peptide. To study effects on biodistribution and pharmacokinetics, we performed 89Zr-CX-072 positron emission tomography (PET) imaging.
Phase I, First-in-Human Study of the Probody Therapeutic CX-2029 in Adults with Advanced Solid Tumor Malignancies. [2023]PROCLAIM-CX-2029 is a phase I first-in-human study of CX-2029, a Probody-drug conjugate targeting CD71 (transferrin receptor 1) in adults with advanced solid tumors. Although the transferrin receptor is highly expressed across multiple tumor types, it has not been considered a target for antibody-drug conjugates (ADCs) due to its broad expression on normal cells. CX-2029 is a masked form of a proprietary anti-CD71 antibody conjugated to monomethyl auristatin E, designed to be unmasked in the tumor microenvironment by tumor-associated proteases, therefore limiting off-tumor toxicity and creating a therapeutic window for this previously undruggable target.
CX-072 (pacmilimab), a Probody PD-L1 inhibitor, in combination with ipilimumab in patients with advanced solid tumors (PROCLAIM-CX-072): a first-in-human, dose-finding study. [2022]Probody® therapeutics are antibody prodrugs designed to be activated by tumor-associated proteases. This conditional activation restricts antibody binding to the tumor microenvironment, thereby minimizing 'off-tumor' toxicity. Here, we report the phase 1 data from the first-in-human study of CX-072 (pacmilimab), a Probody immune checkpoint inhibitor directed against programmed death-ligand 1 (PD-L1), in combination with the anti-cytotoxic T-lymphocyte-associated protein 4 (anti-CTLA-4) antibody ipilimumab.
Probody Therapeutics: An Emerging Class of Therapies Designed to Enhance On-Target Effects with Reduced Off-Tumor Toxicity for Use in Immuno-Oncology. [2023]The deep and durable antitumor effects of antibody-based immunotherapies such as immune checkpoint inhibitors (ICIs) have revolutionized oncology and transformed the therapeutic landscape for many cancers. Several anti-programmed death receptor 1 and anti-programmed death receptor ligand 1 antibodies have been approved for use in advanced solid tumors, including melanoma, non-small cell lung cancer, bladder cancer, and other cancers. ICIs are under development across many tumor types and preliminary results are compelling. However, ICIs have been associated with severe immune-related adverse events (irAEs), including rash, diarrhea, colitis, hypophysitis, hepatotoxicity, and hypothyroidism, which in some cases lead to high morbidity, are potentially life-threatening, and limit the duration of treatment. The incidence of severe irAEs increases further when programmed cell death-1 and programmed cell death ligand-1 inhibitors are combined with anti-CTLA-4 and/or other multidrug regimens. Probody therapeutics, a new class of recombinant, proteolytically activated antibody prodrugs are in early development and are designed to exploit the hallmark of dysregulation of tumor protease activity to deliver their therapeutic effects within the tumor microenvironment (TME) rather than peripheral tissue. TME targeting, rather than systemic targeting, may reduce irAEs in tissues distant from the tumor. Probody therapeutic technology has been applied to multiple antibody formats, including immunotherapies, Probody drug conjugates, and T-cell-redirecting bispecific Probody therapeutics. In preclinical models, Probody therapeutics have consistently maintained anticancer activity with improved safety in animals compared with the non-Probody parent antibody. In the clinical setting, Probody therapeutics may expand or create therapeutic windows for anticancer therapies.
Conditional PD-1/PD-L1 Probody Therapeutics Induce Comparable Antitumor Immunity but Reduced Systemic Toxicity Compared with Traditional Anti-PD-1/PD-L1 Agents. [2023]Immune-checkpoint blockade has revolutionized cancer treatment. However, most patients do not respond to single-agent therapy. Combining checkpoint inhibitors with other immune-stimulating agents increases both efficacy and toxicity due to systemic T-cell activation. Protease-activatable antibody prodrugs, known as Probody therapeutics (Pb-Tx), localize antibody activity by attenuating capacity to bind antigen until protease activation in the tumor microenvironment. Herein, we show that systemic administration of anti-programmed cell death ligand 1 (anti-PD-L1) and anti-programmed cell death protein 1 (anti-PD-1) Pb-Tx to tumor-bearing mice elicited antitumor activity similar to that of traditional PD-1/PD-L1-targeted antibodies. Pb-Tx exhibited reduced systemic activity and an improved nonclinical safety profile, with markedly reduced target occupancy on peripheral T cells and reduced incidence of early-onset autoimmune diabetes in nonobese diabetic mice. Our results confirm that localized PD-1/PD-L1 inhibition by Pb-Tx can elicit robust antitumor immunity and minimize systemic immune-mediated toxicity. These data provide further preclinical rationale to support the ongoing development of the anti-PD-L1 Pb-Tx CX-072, which is currently in clinical trials.
Model-Informed Drug Development of the Masked Anti-PD-L1 Antibody CX-072. [2021]CX-072 is an anti-PD-L1 (programmed death ligand 1) Probody therapeutic (Pb-Tx) designed to be preferentially activated by proteases in the tumor microenvironment and not in healthy tissue. Here, we report the model-informed drug development of CX-072. A quantitative systems pharmacology (QSP) model that captured known mechanisms of Pb-Tx activation, biodistribution, elimination, and target engagement was used to inform clinical translation. The QSP model predicted that a trough level of masked CX-072 (intact CX-072) of 13-99 nM would correspond to a targeted, 95% receptor occupancy in the tumor. The QSP model predictions appeared consistent with preliminary human single-dose pharmacokinetic (PK) data following CX-072 0.03-30.0 mg/kg as monotherapy: CX-072 circulated predominantly as intact CX-072 with minimal evidence of target-mediated drug disposition. A preliminary population PK (POPPK) analysis based upon 130 subjects receiving 0.03-30.0 mg/kg as monotherapy included a provision for a putative time-dependent and dose-dependent antidrug antibody (ADA) effect on clearance (CL) with a mixture model. Preliminary POPPK estimates for intact CX-072 time-invariant CL and volume of distribution were 0.306 L/day and 4.84 L, respectively. Exposure-response analyses did not identify statistically significant relationships with best change from baseline sum of measurements and either adverse events of grade ≥ 3 or of special interest. Simulations suggested that > 95% of patients receiving CX-072 10 mg/kg every two weeks would exceed the targeted trough level regardless of ADA, and that dose adjustment by body weight was not necessary, supporting a fixed 800 mg dose for evaluation in phase II.
The tumor targeting performance of anti-CD166 Probody drug conjugate CX-2009 and its parental derivatives as monitored by 89Zr-immuno-PET in xenograft bearing mice. [2021]Probody® therapeutics are recombinant masked monoclonal antibody (mAb) prodrugs that become activated by proteases present in the tumor microenvironment. This makes them attractive for use as Probody drug conjugates (PDCs). CX-2009 is a novel PDC with the toxic drug DM4 coupled to an anti-CD166 Probody therapeutic. CD166 is overexpressed in multiple tumor types and to a lesser extent by healthy tissue. Methods: The tumor targeting potential of CX-2009 was assessed by performing 89Zr-immuno-PET/biodistribution/therapy studies in a CD166-positive H292 lung cancer mouse model. Head-to-head comparisons of CX-2009 with the Probody therapeutic without DM4 (CX-191), the unmasked antibody drug conjugate (ADC) CX-1031, and the parental mAb CX-090 were performed. All constructs were 89Zr labeled in a GMP compliant way, administered at 10, 110, or 510 µg, and ex vivo biodistribution was assessed at 24, 72, and 168 hours post-injection. Results: Comparable biodistribution was observed for all constructs, confirmed with PET/CT. Tumors showed the highest uptake: 21.8 ± 2.3 ([89Zr]Zr-CX-2009), 21.8 ± 5.0 ([89Zr]Zr‑CX-191), 18.7 ± 2.5 ([89Zr]Zr-CX-1031) and 20.8 ± 0.9 %ID/g ([89Zr]Zr-CX-090) at 110 µg injected. Increasing the dose to 510 µg resulted in lower tumor uptake and higher blood levels for all constructs, suggesting receptor saturation. In addition, CX-2009 and CX-1031 showed similar therapeutic potential. Conclusions: CX-2009 is optimally capable of targeting CD166-expressing tumors when compared with its derivatives, implying that enzymatic activation inside the tumor, required to allow CD166 binding, does not limit tumor targeting. Because CX-2009 does not bind to mouse CD166, however, reduced targeting of healthy organs should be confirmed in ongoing clinical 89Zr-immuno-PET studies.
A T-cell engaging bispecific antibody with a tumor-selective bivalent folate receptor alpha binding arm for the treatment of ovarian cancer. [2022]The use of T-cell engagers (TCEs) to treat solid tumors is challenging, and several have been limited by narrow therapeutic windows due to substantial on-target, off-tumor toxicities due to the expression of low levels of target antigens on healthy tissues. Here, we describe TNB-928B, a fully human TCE that has a bivalent binding arm for folate receptor alpha (FRα) to selectively target FRα overexpressing tumor cells while avoiding the lysis of cells with low levels of FRα expression. The bivalent design of the FRα binding arm confers tumor selectivity due to low-affinity but high-avidity binding to high FRα antigen density cells. TNB-928B induces preferential effector T-cell activation, proliferation, and selective cytotoxic activity on high FRα expressing cells while sparing low FRα expressing cells. In addition, TNB-928B induces minimal cytokine release compared to a positive control TCE containing OKT3. Moreover, TNB-928B exhibits substantial ex vivo tumor cell lysis using endogenous T-cells and robust tumor clearance in vivo, promoting T-cell infiltration and antitumor activity in mouse models of ovarian cancer. TNB-928B exhibits pharmacokinetics similar to conventional antibodies, which are projected to enable favorable administration in humans. TNB-928B is a novel TCE with enhanced safety and specificity for the treatment of ovarian cancer.