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NUC-3373 in Combination With Other Agents in Patients With Advanced Solid Tumours

A Phase Ib/II Open Label, Multi-arm, Parallel Cohort Dose Finding and Expansion Study to Assess the Safety, Pharmacokinetics and Efficacy of NUC-3373, a Nucleotide Analogue, Given in Combination With Standard Approved Agents in Patients With Advanced Solid Tumours

Status
Terminated
Phases
Phase 1Phase 2
Study type
Interventional
Source
ClinicalTrials.gov
Registry ID
NCT05714553
Enrollment
19
Registered
2023-02-06
Start date
2023-03-08
Completion date
2025-05-30
Last updated
2026-07-23

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Advanced Cancer, Advanced Solid Tumor, Classical Hodgkin Lymphoma, Endometrial Carcinoma, Gastric Cancer, Head and Neck Squamous Cell Carcinoma, Melanoma, Metastatic Cancer, MSI-H Colorectal Cancer, Neoplasm Malignant, Non Small Cell Lung Cancer, Oesophageal Carcinoma, Pleural Mesothelioma, Renal Cell Carcinoma, Subungual Squamous Cell Carcinoma, Triple Negative Breast Cancer, Urothelial Carcinoma

Keywords

NuCana plc, NUC-3373, Fosifloxuridine nafalbenamide, Leucovorin, Pembrolizumab, Docetaxel, Antineoplastic agents, Chemotherapy, Locally advanced, Metastatic

Brief summary

This study is an open-label, multi-arm, parallel cohort, dose validation and expansion design. The study is modular in design, allowing evaluation of the safety, efficacy and pharmacokinetics (PK) of NUC-3373 in combination with other agents for the treatment of patients with different tumour types. Each module is designed to evaluate a different NUC-3373 combination and consists of a dose-validation phase (Phase Ib) and a dose-expansion phase (Phase II). Phase Ib of each module will determine the safety and tolerability of the combinations for further clinical evaluation in Phase II. Approximately 6-20 evaluable patients will be enrolled in the Phase Ib stage of each module to determine safety, tolerability, and preliminary efficacy of NUC-3373 in combination with other agents. Each module will then move into Phase II to enable a further assessment of safety and efficacy in approximately 20-40 patients. Module 1 will assess NUC-3373 + leucovorin (LV) in combination with pembrolizumab for the treatment of patients with advanced/metastatic solid tumours who have progressed on ≤2 prior therapies for metastatic disease, that may have included 1 prior immunotherapy-containing regimen (either monotherapy or in combination with chemotherapy) or who have not progressed but where addition of NUC-3373 + LV to standard pembrolizumab monotherapy may be appropriate (e.g., patients who could not tolerate post- immuno-oncology (IO) standard of care therapy). Module 2 will assess NUC-3373 + LV in combination with docetaxel for the treatment of patients with advanced/metastatic non-small cell lung cancer (NSCLC) or pleural mesothelioma who have progressed on, or were unable to tolerate, 1 or 2 prior lines of cytotoxic chemotherapy-containing regimens for advanced/metastatic disease. The opening of each module will be at the discretion of the Sponsor. Further modules may be added as non-clinical and clinical data become available to support additional NUC-3373 combinations and tumour types.

Interventions

Intravenous infusion

DRUGLeucovorin

Intravenous infusion

DRUGPembrolizumab

Intravenous infusion

DRUGDocetaxel

Intravenous infusion

Sponsors

NuCana plc
Lead SponsorOTHER

Study design

Allocation
NON_RANDOMIZED
Intervention model
PARALLEL
Primary purpose
TREATMENT
Masking
NONE

Eligibility

Sex/Gender
ALL
Age
18 Years to No maximum
Healthy volunteers
No

Inclusion criteria

(all modules): 1. Provision of written informed consent. 2. Confirmed diagnosis of one of the protocol-specified tumour types (refer to the relevant module for specific criteria). 3. Age ≥18 years. 4. Minimum life expectancy of ≥12 weeks. 5. Eastern Cooperative Oncology Group (ECOG) Performance status 0 or 1. 6. Measurable disease as defined by RECIST v1.1. 7. Adequate bone marrow function as defined by absolute neutrophil count (ANC) ≥1.5×109/L, platelet count ≥100×109/L (with no evidence of bleeding), and haemoglobin ≥9 g/dL. 8. Adequate liver function (refer to the relevant module for specific criteria). 9. Adequate renal function assessed as serum creatinine \<1.5× upper limit of normal (ULN) and glomerular filtration rate ≥50 mL/min (calculated by the Cockcroft-Gault method). 10. Serum albumin ≥3 g/dL. 11. For the module in which the patient will participate, there are no contra-indications to receiving the approved partner combination drugs. 12. Ability to comply with protocol requirements. 13. Female patients of child-bearing potential must have a negative pregnancy test within 7 days prior to the first study drug administration. This criterion does not apply to patients who have had a previous hysterectomy or bilateral oophorectomy. Male patients and female patients of child-bearing potential must agree to practice true abstinence or to use two forms of contraception, one of which must be highly effective. These forms of contraception must be used from the time of signing consent, throughout the treatment period, and for 6 months following the last dose of any study medication. Oral or injectable contraceptive agents cannot be the sole method of contraception. 14. Patients must have been advised to take measures to avoid or minimize exposure to ultraviolet (UV) light for the duration of study participation and for a period of 4 weeks following the last dose of study medication. Additional Module 1 Inclusion Criteria: 1. Confirmed diagnosis of a solid tumour, with evidence of locally advanced/unresectable or metastatic disease, for which pembrolizumab treatment would be appropriate (e.g., melanoma, classical Hodgkin lymphoma, NSCLC, renal cell carcinoma (RCC), urothelial carcinoma, head and neck squamous cell carcinoma (HNSCC), cutaneous squamous cell carcinoma (cSCC), oesophageal carcinoma, microsatellite instability (MSI) high colorectal (CRC), gastric cancer, triple negative breast cancer (TNBC), and endometrial carcinoma). 2. Must have progressed on ≤2 prior lines of therapy for advanced/metastatic disease, that may have included 1 prior line of an immunotherapy-containing regimen (either monotherapy or in combination with chemotherapy). Patients who have not progressed but where addition of NUC-3373 + LV to standard pembrolizumab monotherapy may be appropriate are also eligible (e.g., patients who could not tolerate post-IO standard of care therapy). 3. Patient must be willing to undergo a new tumour biopsy at Screening and during therapy on the study. Biopsies are mandatory for patient inclusion, except where taking a biopsy would be associated with unacceptable clinical risk due to the location of the disease. A prior (archival) biopsy that is less than 6 months old (from the date of Cycle 1Day 1; C1D1) may be substituted for a fresh tumour biopsy at Screening. 4. Adequate liver function, as defined by serum total bilirubin ≤1.5×ULN, aspartate aminotransferase (AST) and alanine aminotransferase (ALT) ≤2.5×ULN (or ≤5×ULN if liver metastases are present). Additional Module 2 Inclusion Criteria: 1. Confirmed diagnosis of NSCLC (any histology) or pleural mesothelioma (any histology) with evidence of locally advanced/unresectable or metastatic disease. 2. Must have progressed on, or were unable to tolerate, 1 or 2 prior lines of cytotoxic chemotherapy-containing standard of care regimens for advanced/metastatic disease (not including neoadjuvant or adjuvant therapy). Additional prior lines of treatment with targeted agents or immunotherapy are allowed as long as they were not given in combination with cytotoxic chemotherapy. Prior regimens in which one drug is substituted for another due to toxicity count as 1 line of treatment. Prior treatment with docetaxel for metastatic disease is not allowed. 3. Adequate liver function, as defined by serum total bilirubin \<ULN, AST and ALT ≤2.5×ULN (or ≤5×ULN if liver metastases are present). In the event of concomitantly increased alkaline phosphatase (ALP) values \>2.5×ULN, AST and ALT must be \<1.5×ULN.

Exclusion criteria

(all modules): 1. History of hypersensitivity or current contra-indications to 5-fluorouracil (5-FU), floxuridine (FUDR), capecitabine (refer to latest package inserts), or the components of the NUC-3373 drug product formulation (super refined polysorbate 80 \[SRP80\], dimethylacetamide \[DMA\]). 2. Symptomatic central nervous system or leptomeningeal metastases. 3. Symptomatic ascites, ascites currently requiring drainage procedures or ascites requiring drainage over the 3 months prior to date of first dose of study drug. 4. Chemotherapy, hormonal therapy, radiotherapy (other than a short cycle of palliative radiotherapy, e.g., for bone pain\*), immunotherapy, biological agents, or exposure to another investigational agent within 21 days (or four times the half-life for molecular targeted agents, whichever is shorter) of first administration of study treatment: 1. For nitrosoureas and mitomycin C within 6 weeks of first administration of NUC-3373 2. Corticosteroid treatment is allowed during screening but should be weaned to a dose of 10 mg prednisolone (or steroid equivalent) by Cycle 1 Day 1 \* Palliative radiotherapy during participation in the study is permitted, but should not be concurrent with study treatment and recovery should be allowed to prevent overlapping toxicity. It should not include a target lesion. 5. Residual toxicities from prior chemotherapy, immunotherapy or radiotherapy which have not regressed to Grade ≤1 severity (Common Terminology Criteria for Adverse Events (CTCAE) v5.0), except for alopecia, peripheral neuropathy and ototoxicity (which are excluded if ≥Grade 3). 6. Uncontrolled concurrent cancer other than the indication under investigation. Patients with a concurrent cancer whose natural history or treatment does not have the potential to interfere with safety or efficacy assessment are eligible. 7. Presence of an active bacterial or viral infection (including severe acute respiratory syndrome coronavirus 2 (SARS-CoV- 2), Herpes Zoster or chicken pox), or known active hepatitis B or C. 8. Presence of any uncontrolled concurrent serious illness, medical condition or other medical history, including laboratory results, which, in the Investigator's opinion, would be likely to interfere with the patient's ability to participate in the study or with the interpretation of the results, including any of the following: 1. Congestive heart failure (New York Heart Association Class III or Class IV) 2. Clinically significant coronary heart disease or myocardial infarction within 6 months of the first dose of study medication or high risk of uncontrolled arrythmia 3. Unstable or poorly controlled angina pectoris 4. Complete left bundle branch, bifascicular block or other clinically significant abnormal electrocardiogram (ECG) finding 5. Corrected QT (QTc) interval \>470 milliseconds 6. History of or current risk factor for torsade de pointes (e.g., heart failure, hypokalaemia, or a family history of long QT syndrome) 7. History of severe skin reactions 8. History of severe ocular disorders 9. Interstitial pneumonitis or pulmonary fibrosis 9. Any condition (e.g., known or suspected poor compliance, psychological instability, geographical location, etc.) that, in the judgment of the Investigator, may affect the patient's ability to sign the informed consent and undergo study procedures. 10. Currently pregnant, lactating or breastfeeding. 11. Required concomitant use of drugs known to prolong QT/QTc interval. 12. Required concomitant use of strong CYP3A4 inducers or strong CYP3A4 inhibitors. The use of strong CYP3A4 inducers within 2 weeks of first receipt of study drug or the use of strong CYP3A4 inhibitors within 1 week of first receipt of study drug is also excluded. 13. Use of live attenuated vaccines against infectious diseases (e.g., measles mumps rubella \[MMR combined vaccines\], Rotavirus, Chickenpox, yellow fever) within 4 weeks of initiation of study treatment. 14. Known dihydropyrimidine dehydrogenase (DPD) or thymidine phosphorylase (TYMP) mutations associated with toxicity to fluoropyrimidines. 15. Full-dose anti-coagulation treatment is prohibited. Use of warfarin and other types of long-acting anti-coagulants (such as phenprocoumon and anti-Xa inhibitors with a half-life of \>12 hours) is prohibited within 4 weeks of the first dose of study treatment. Patients requiring low dose anti-coagulant treatment should switch to low molecular weight heparin or anti-Xa inhibitors with a half-life of ≤12 hours. Additional Module 1

Design outcomes

Primary

MeasureTime frameDescription
Number of Participants With DLTs in Each ModuleAssessed during Cycle 1 (first 28 days) in Module 1 and during Cycles 1 and 2 (first 56 days) in Module 2The outcome measure presented is the number of DLTs per module

Secondary

MeasureTime frameDescription
Number of Patients Achieving a Reduction in Tumour Volume (Objective Response Rate; ORR)Assessed from baseline to 30 days after last dose of study drug, up to 20 monthsObjective response rate, defined as the percentage of patients achieving a complete (CR) or partial response (PR) to treatment. Response was measured by MRI scan and assessed per Response Evaluation Criteria in Solid Tumors (RECIST v1.1) criteria in Module 2 and by immune RECIST (iRECIST) criteria in Module 1: CR= disappearance of all target lesions PR= at least a 30% decrease in the sum of the longest diameter of target lesions
Number of Patients Achieving a Reduction or Stabilisation in Tumor Volume (Disease Control Rate; DCR)Assessed from baseline to 30 days after the last dose of study drug, up to 20 monthsDisease control rate, defined as the number of patients achieving a response (CR or PR) or stable disease (SD) as their best overall response. Disease control was measured by MRI scan and assessed using Response Evaluation Criteria in Solid Tumors (RECIST v1.1) criteria in Module 2 and immune RECIST (iRECIST) criteria in Module 1: CR= disappearance of all target lesions PR= at least a 30% decrease in the sum of the longest diameter of target lesions SD= neither sufficient shrinkage to qualify for PR nor sufficient increase to qualify for progressive disease

Countries

United Kingdom

Participant flow

Recruitment details

A total of 26 patients were screened and 19 patients were enrolled across 3 sites in the UK between March 2023 and May 2025.

Pre-assignment details

This study was a modular Phase Ib/II study, with each module consisting of a Phase Ib dose-validation phase and a potential Phase II dose-expansion phase. However, the Phase II dose-expansion phase was not initiated in either module. All participants reported in the Participant Flow were enrolled in the Phase Ib part. Arms/groups were combined within each module because no participants were assigned to or treated in any Phase II expansion arm.

Baseline characteristics

Characteristic
Age, Continuous69.0 Years
ECOG performance status
0
1 Participants
ECOG performance status
1
10 Participants
Primary tumor location
Anal
1 Participants
Primary tumor location
Bladder (urothelial)
2 Participants
Primary tumor location
Cutaneous melanoma
3 Participants
Primary tumor location
NSCLC
6 Participants
Primary tumor location
Oropharyngeal
2 Participants
Primary tumor location
Pancreatic
1 Participants
Primary tumor location
Pleural mesothelioma
1 Participants
Primary tumor location
Rectal
1 Participants
Primary tumor location
Sinonasal
1 Participants
Race (NIH/OMB)
American Indian or Alaska Native
0 Participants
Race (NIH/OMB)
Asian
0 Participants
Race (NIH/OMB)
Black or African American
0 Participants
Race (NIH/OMB)
More than one race
0 Participants
Race (NIH/OMB)
Native Hawaiian or Other Pacific Islander
0 Participants
Race (NIH/OMB)
Unknown or Not Reported
0 Participants
Race (NIH/OMB)
White
4 Participants
Sex: Female, Male
Female
2 Participants
Sex: Female, Male
Male
2 Participants
Tumor stage
Stage I
1 Participants
Tumor stage
Stage II
1 Participants
Tumor stage
Stage III
0 Participants
Tumor stage
Stage IV
4 Participants
Tumor stage
Unknown
0 Participants

Adverse events

Event typeEG000
affected / at risk
EG001
affected / at risk
deaths
Total, all-cause mortality
10 / 133 / 4
other
Total, other adverse events
13 / 134 / 4
serious
Total, serious adverse events
7 / 133 / 4

Outcome results

None listed

Source: ClinicalTrials.gov · Data processed: Jul 24, 2026