Metastatic Castration-Resistant Prostate CancerPhase 1/2NCT03568656
Study to Evaluate CCS1477 in Advanced Tumours
A Phase 1/2 study testing CCS1477, Abiraterone acetate and Enzalutamide in people with Metastatic Castration-Resistant Prostate Cancer and Metastatic Breast Cancer, run by CellCentric Ltd. at 19 sites in 6 countries.
Trial summary
A Phase 1/2a study to assess the safety, tolerability, PK and biological activity of CCS1477 in patients with metastatic castration resistant prostate cancer, metastatic breast cancer, non-small cell lung cancer or advanced solid tumours. Read more about this study
- Who is it for?
- Ages 18 years and older
- Conditions the study is for
- Metastatic Castration-Resistant Prostate Cancer, Metastatic Breast Cancer, Non-small Cell Lung Cancer
- What is being tested?
- CCS1477, Abiraterone acetate and Enzalutamide
- Type of treatment
- Pill or oral medicine, Injection or infusion
- Could I receive a placebo?
- No, everyone receives an active treatment
- How many people
- 219 participants
- Where
- 19 sitesin 6 countries
- Study dates
- 23 Jul 2018to 6 Jul 2025
- Phase
- Phase 1/2
- Are there results?
- Yes, posted in the registrySummary in the doctors' view
Key requirements
Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.
- Ages 18 years and older
- All sexes
- No healthy volunteers
- Adult, Older adult
Who may be able to join
- Provision of consent
- ECOG performance status 0-1
- Assessable disease (by CT, MRI, bone scan or X-ray)
- Adequate organ function
- Highly effective contraception measures for duration of study
- Additional inclusion criteria for mCRPC patients only:
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- Previously received abiraterone and/or enzalutamide (or equivalent anti-androgen), and docetaxel (unless ineligible or refused)
- Progressive disease documented by one or more of the following:
- Biochemical progression defined as at least 2 stepwise increases in a series of any 3 PSA values
- Progression as defined by RECIST v1.1 guideline for assessment of malignant soft tissue disease.
- Progression defined as two or more new metastatic bone lesions confirmed on bone scan from a previous assessment
- PSA at screening ≥2 μg/L
- Serum testosterone concentration ≤50 ng/dL
- Serum albumin >2.5 g/dL
- Additional inclusion criteria for patients in CCS1477 plus abiraterone combination arm:
- Patients must have previously progressed on abiraterone treatment
- Patients whose last dose of abiraterone is greater than 6 months prior to start of study treatment will receive a 4-week run-in treatment with abiraterone to confirm refractoriness to abiraterone treatment
- Additional inclusion criteria for patients in CCS1477 plus enzalutamide combination arm:
- Patients must have previously progressed on enzalutamide treatment
- Patients whose last dose of enzalutamide is greater than 6 months prior to start of study treatment will receive a 4-week run-in treatment with enzalutamide to confirm refractoriness to enzalutamide treatment
- Additional inclusion criteria for patients in mutation arm:
- Advanced solid tumour with identification of markers which may indicate potential for response to p300/CBP inhibition. Markers include loss of function mutations in CREBBP, EP300 or ARID1A, MYC gene amplifications or rearrangements and androgen receptor (AR) gene amplifications or over-expression.
Who cannot join
- Intervention with any chemotherapy, investigational agents or other anti-cancer drugs within 14 days or 5 half-lives of the first dose
- Radiotherapy with a wide field of radiation or to more than 30% of the bone marrow within 4 weeks of the first dose of study treatment
- Major surgical procedure or significant traumatic injury within 4 weeks of the first dose of study treatment
- Strong inhibitors of CYP3A4 or CYP3A4 substrates with a narrow therapeutic range taken within 2 weeks of the first dose of study treatment
- Strong inducers of CYP3A4 within 4 weeks of the first dose of study treatment
- Statins; patients should discontinue statins prior to starting study treatment
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- Any unresolved reversible toxicities from prior therapy >CTCAE grade 1 at the time of starting study treatment
- Any evidence of severe or uncontrolled systemic diseases
- Any known uncontrolled inter-current illness
- QTcF prolongation (> 480 msec).
- Primary brain tumours or known or suspected brain metastases.
- Additional exclusion criteria for patients in CCS1477 plus abiraterone combination arm:
- Clinically significant cardiac abnormalities
- Additional exclusion criteria for patients in CCS1477 plus enzalutamide combination arm:
- History of seizures or other predisposing factors
- Use of substrates with a narrow therapeutic index metabolised by CYP2C9 or CYP2C19 within 2 weeks of the first dose of study treatment
- Clinically significant cardiac abnormalities
Trial locations and contacts
19 sites in 6 countries.
19 sites in 6 countries
United Kingdom10 sites
Belfast City Hospital
Belfast, BT9 7AB
Queen Elizabeth Hospital Cancer Centre
Birmingham, B15 2TH
Cambridge University Hospital
Cambridge, CB2 0QQ
Edinburgh Cancer Centre Western General Hospital
Edinburgh, EH4 2XU
The Beatson West of Scotland Cancer Centre
Glasgow, G12 0YN
Leicester Royal Infirmary
Leicester, LE1 5WW
The Christie Hospital
Manchester, M20 4BX
Freeman Hospital
Newcastle, NE7 7DN
University Hospital Southampton
Southampton, SO16 6YD
Royal Marsden Hospital
Sutton, SM2 5NG
France3 sites
Institute Bergonie
Bordeaux, 33000
Hôpital Europeen Georges Pompidou
Paris, 75015
Institute Gustave Roussy
Villejuif, 94805
United States2 sites
Dana-Farber Cancer Institute
Boston, Massachusetts, 02215
Thomas Jefferson University, Sidney Kimmel Cancer Center
Philadelphia, Pennsylvania, 19107
Spain2 sites
Hospital Vall d'Hebron, VHIO
Barcelona, 08035
START CIOCC Hospital Universitario HM
Madrid, 28050
About this study
Official title: An Open-label Phase I/IIa Study to Evaluate the Safety and Efficacy of CCS1477 as Monotherapy and in Combination, in Patients With Advanced Solid/Metastatic Tumours.
A Phase 1/2a study to assess the safety, tolerability, PK and biological activity of CCS1477 in patients with metastatic castration resistant prostate cancer, metastatic breast cancer, non-small cell lung cancer or advanced solid tumours.
Read the detailed description
The Steering Committee closed selected cohorts, in accordance with its responsibilities, after findings from earlier cohorts indicated that further evaluation of those cohorts was no longer warranted. The remaining cohorts were completed as specified in the protocol. Therefore, the study was considered completed.
- Conditions
- Metastatic Castration-Resistant Prostate Cancer, Metastatic Breast Cancer, Non-small Cell Lung Cancer, Advanced Solid Tumors
- Being tested
- CCS1477, Abiraterone acetate, Enzalutamide, Darolutamide, Olaparib
- Medical subject headings
- Breast Neoplasms, Carcinoma, Non-Small-Cell Lung
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
CCS1477Drug
Capsules, oral
Abiraterone acetateDrug
Abiraterone acetate 500mg tablets plus prednisone/prednisolone
EnzalutamideDrug
Enzalutamide 40mg capsules/tablets
DarolutamideDrug
300mg tablets
OlaparibDrug
150mg tablets
AtezolizumabDrug
840mg/14ml concentrate for solution for infusion vials
| Study group | Role | What they receive |
|---|---|---|
| CCS1477 dose escalation - mCRPC | Experimental | CCS1477 monotherapy in patients with mCRPC Receives: Drug: CCS1477 |
| CCS1477 expansion phase - mCRPC | Experimental | CCS1477 monotherapy in patients with mCRPC Receives: Drug: CCS1477 |
| CCS1477 and abiraterone acetate, combination dose finding and expansion - mCRPC | Experimental | CCS1477 plus abiraterone acetate in patients with mCRPC Receives: Drug: CCS1477; Drug: Abiraterone acetate |
| CCS1477 and enzalutamide, combination dose finding and expansion - mCRPC | Experimental | CCS1477 plus enzalutamide in patients with mCRPC Receives: Drug: CCS1477; Drug: Enzalutamide |
| CCS1477 Monotherapy - Solid tumours | Experimental | CCS1477 expansion phase in patients with advanced solid tumours with molecular markers which may indicate potential for response to p300/CBP inhibition Receives: Drug: CCS1477 |
| CCS1477 and darolutamide, combination dose finding and expansion - mCRPC | Experimental | CCS1477 plus darolutamide in patients with mCRPC Receives: Drug: CCS1477; Drug: Darolutamide |
| CCS1477 and olaparib, combination dose finding and expansion - mCRPC and metastatic breast cancer | Experimental | CCS1477 plus olaparib in patients with mCRPC or metastatic breast cancer. Receives: Drug: CCS1477; Drug: Olaparib |
| CCS1477 and atezolizumab, combination dose finding and expansion - non-small cell lung cancer | Experimental | CCS1477 plus atezolizumab in patients with non-small cell lung cancer Receives: Drug: CCS1477; Drug: Atezolizumab |
What is being measured
The primary outcome is the main question the study is designed to answer.
Number of Participants With Treatment-Emergent Adverse Events (TEAEs), Serious TEAEs and TEAEs Leading to Withdrawal
Adverse Event (AE) was defined any untoward medical occurrence in a participant administered with a study intervention, which does not necessarily have a causal relationship with the treatment. Serious AE (SAE) was defined AE that resulted in any of the following outcomes: death; life threatening; persistent/significant disability/incapacity; initial/prolonged inpatient hospitalization; congenital anomaly/birth defect. TEAEs: TEAEs were defined as those events with onset dates/time occurring after study intervention administration or events that worsen after study intervention administration. TEAEs included serious TEAEs and non-serious TEAEs. Number of participants with TEAEs leading to withdrawal of study intervention was also reported.
Measured: From signing informed consent until the end of the follow-up period (Up to 363 weeks)
Number of Participants With Worst Shift in Laboratory Data-Hematology According to Common Terminology Criteria for Adverse Events (CTCAE)-Version 5 Grades
Adverse events were graded according to the National Cancer Institute (NCI) Common Terminology Criteria for Adverse Events (CTCAE) Version 5.0, where Grade 1 = mild, Grade 2 = moderate, Grade 3 = severe, Grade 4 = life-threatening, and Grade 5 = death related to the adverse event. Number of participants with worst shift in hematology according to Common Terminology Criteria for Adverse Events (CTCAE) grades were reported.
Measured: From first dose of study drug in Cycle 1 up to and including 28 days after last dose of study intervention (Up to 363 weeks) (Cycle length was 4 weeks for Cycles 1-6 and 6 weeks for Cycle 7 and subsequent cycles.)
Number of Participants With Worst Shift in Laboratory Data-Biochemistry According to Common Terminology Criteria for Adverse Events (CTCAE)-Version 5 Grades
Adverse events were graded according to the National Cancer Institute (NCI) Common Terminology Criteria for Adverse Events (CTCAE) Version 5.0, where Grade 1 = mild, Grade 2 = moderate, Grade 3 = severe, Grade 4 = life-threatening, and Grade 5 = death related to the adverse event. Number of participants with worst shift in biochemistry according to Common Terminology Criteria for Adverse Events (CTCAE) grades were reported.
Measured: From first dose of study drug in Cycle 1 up to and including 28 days after last dose of study intervention (Up to 363 weeks) (Cycle length was 4 weeks for Cycles 1-6 and 6 weeks for Cycle 7 and subsequent cycles.)
Number of Participants With Clinically Significant Change From Baseline in Laboratory Parameters - Urinalysis
The urinalysis measurements included glucose, protein and blood. Number of participants with clinically significant changes from baseline in urinalysis values were reported. Clinically Significance was decided by investigator.
Measured: From first dose of study drug in Cycle 1 up to and including 28 days after last dose of study intervention (Up to 363 weeks) (Cycle length was 4 weeks for Cycles 1-6 and 6 weeks for Cycle 7 and subsequent cycles.)
Number of Participants With Clinically Significant Change From Baseline in Vital Signs
The vital signs measurements included blood pressure, heart rate, respiration rate and temperature. Number of participants with clinically significant changes from baseline in vital signs values were reported. Clinically Significance was decided by investigator.
Measured: From first dose of study drug in Cycle 1 up to and including 28 days after last dose of study intervention (Up to 363 weeks) (Cycle length was 4 weeks for Cycles 1-6 and 6 weeks for Cycle 7 and subsequent cycles.)
Number of Participants With Worst Shift in QTcF According to Common Terminology Criteria for Adverse Events (CTCAE)-Version 5 Grades
Twelve-lead Electrocardiograms (ECGs) were obtained after the participant was in semi-supine for 5 minutes. Three ECGs were taken at each timepoint at about 1-minute intervals. QTcF was calculated using the Fridericia formula: QTcF = QT ÷ RR^(1/3), where QT is the measured QT interval in milliseconds and RR is the interval between two consecutive R waves on the ECG expressed in seconds. It was categorized as less than equal to (<=) 450 milliseconds (msec), more than (>) 450 to <=480 msec, > 480 to <= 500 msec and > 500 msec.
Measured: From first dose of study drug in Cycle 1 up to and including 28 days after last dose of study intervention (Up to 363 weeks) (Cycle length was 4 weeks for Cycles 1-6 and 6 weeks for Cycle 7 and subsequent cycles)
Secondary outcomes (7)
Best Percentage Change From Baseline in Prostate Specific Antigen (PSA) Response in Participants With Metastatic Castration Resistant Prostate Cancer (mCRPC)
Best percentage change from baseline was defined as the largest percentage reduction in PSA levels or the smallest percentage increase in PSA levels in the absence of a reduction.
Measured: At Baseline - Cycle 1 - Day 1, Day 8, Day 15, Day 22 and Day 1 of every cycle from cycle 2 onwards until treatment discontinuation (Up to 363 weeks) (Cycle length was 4 weeks for Cycles 1-6 and 6 weeks for Cycle 7 and subsequent cycles.)
Number of Participants With CTC Response
CTC response was defined as a change from unfavourable (five or more cells per 7.5 mL of blood) at baseline to favourable (four or fewer cells per 7.5 mL) post treatment. Number of participants with overall response were reported. A participant was determined as having an overall CTC response if they had at least one post baseline assessment of 'CTC response'.
Measured: From Baseline - Day 1 Cycle 1 (Predose), Day 1 Cycle 2, Day 1 Cycle 3, Day 1 Cycle 5 up to disease progression or treatment discontinuation (Up to 363 weeks) (Cycle length was 4 weeks for Cycles 1-6 and 6 weeks for Cycle 7 and subsequent cycles)
Objective Response Rate (ORR) According to Response Evaluation Criteria in Solid Tumors (RECIST) Version 1.1
Objective response is defined as any participant with measurable disease who has a best overall response of Partial Response (PR) or Complete Response (CR). CR is defined as the disappearance of all Target Lesions (TLs) since baseline. PR is defined as At least a 30% decrease in the sum of diameters of TLs, taking as reference the baseline sum of diameters.
Measured: From day of study intervention in Cycle 1 until progression or censoring date in the absence of progression (Up to 363 weeks) (Cycle length was 4 weeks for Cycles 1-6 and 6 weeks for Cycle 7 and subsequent cycles)
Radiological Progression Free Survival (rPFS) According to Response Evaluation Criteria in Solid Tumors (RECIST) Version 1.1
Radiological progression free survival (rPFS) was defined as the time from the start of treatment with CCS1477 in Cycle 1 until the earliest objective disease progression defined by RECIST 1.1, Prostate Cancer Clinical Trial Working Group 3 (PCWG-3) bone progression or death by any cause in the absence of progression, regardless of whether the participants withdraws from study medication or receives another anti-cancer therapy prior to progression. Kaplan - Meier estimate was used to calculate the rPFS.
Measured: From day of study intervention in Cycle 1 until progression or censoring date in the absence of progression (Up to 363 weeks) (Cycle length was 4 weeks for Cycles 1-6 and 6 weeks for Cycle 7 and subsequent cycles)
Overall Survival (OS)
Overall survival is defined as the time from the start of treatment with CCS1477 in Cycle 1 until death due to any cause.
Measured: From start of treatment until death (Up to 363 weeks)
Maximum Observed Plasma Concentration (Cmax)
Cmax was obtained directly from concentration versus time curve.
Measured: Cycle 1 Day 1 and Cycle 2 Day 3 (Cycle length was 4 weeks)
Area Under the Plasma Concentration-Time Curve From Time Zero to Infinity (AUC0-24)
AUC0-24 is defined as the area under the concentration-time curve (AUC) from time zero (= dosing time) to 24 hours. AUC0-24 was calculated using the mixed log-linear trapezoidal rule.
Measured: Cycle 1 Day 1 and Cycle 2 Day 3 (Cycle length was 4 weeks)
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted26 Jun 2018
- Study start23 Jul 2018
- Primary completion6 Jul 2025
- Study completion6 Jul 2025
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Posted resultsParticipant flow, outcome measures and adverse events reported by the sponsor.
- Publications (2)Papers the sponsor has linked to this study.
- Other trials for Metastatic Castration-Resistant Prostate CancerStudies of the same condition, open and under way.
- What the trial phases meanHow a treatment moves from first tests in people to approval.
More details
For doctors and researchers: how the study is designed, who runs it, and its registry IDs.
Study design
- Study type
- Interventional
- Phase
- Phase 1/2
- Primary purpose
- Treatment
- Allocation
- Non-randomised
- Intervention model
- Sequential
- Model description
- The RP2D/MTD dose will be determined in Part A. Parts B-H will run in parallel after the completion of Part A.
- Masking
- None (open label)
- Enrolment
- 219 participants (actual)
Sponsor and investigators
- Lead sponsor
- CellCentric Ltd.
- Sponsor type
- Industry (pharma, biotech, devices)
- Responsible party
- Sponsor
- Investigators
- Johann de Bono, MD, Principal investigator, Royal Marsden NHS Foundation Trust
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT03568656
- Sponsor's protocol ID
- CCS1477-01
- Status last verified
- Jul 2026
- First submitted
- 4 Jun 2018
- Last updated
- 25 Sep 2026
- Results posted
- Yes, on ClinicalTrials.gov
- Data monitoring committee
- No
- FDA-regulated drug
- Yes
- FDA-regulated device
- No
- Individual data sharing
- No
Publications
Caligiuri M, Williams GL, Castro J, Battalagine L, Wilker E, Yao L, Schiller S, Toms A, Li P, Pardo E, Graves B, Azofeifa J, Chicas A, Herbertz T, Lai M, Basken J, Wood KW, Xu Q, Guichard SM. FT-6876, a Potent and Selective Inhibitor of CBP/p300, is Active in Preclinical Models of Androgen Receptor-Positive Breast Cancer. Target Oncol. 2023 Mar;18(2):269-285. doi: 10.1007/s11523-023-00949-7. Epub 2023 Feb 24.
PubMed 36826464Eickhoff N, Bergman AM, Zwart W. Homing in on a Moving Target: Androgen Receptor Cistromic Plasticity in Prostate Cancer. Endocrinology. 2022 Oct 11;163(11):bqac153. doi: 10.1210/endocr/bqac153.
PubMed 36125208
Study at a glance
From the registry record, last updated by the sponsor on 25 Sep 2026. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- An Open-label Phase I/IIa Study to Evaluate the Safety and Efficacy of CCS1477 as Monotherapy and in Combination, in Patients With Advanced Solid/Metastatic Tumours.
- ClinicalTrials.gov ID
- NCT03568656
- Acronym / sponsor ID
- CCS1477-01
- Conditions
- Metastatic Castration-Resistant Prostate Cancer, Metastatic Breast Cancer, Non-small Cell Lung Cancer, Advanced Solid Tumors
- Phase
- Phase 1/2
- Study type
- Interventional
- Recruitment status
- Completed
- Enrolment
- 219 participants (actual)
- Lead sponsor
- CellCentric Ltd.Industry (pharma, biotech, devices)
- Study start
- 23 Jul 2018 (actual)
- Primary completion
- 6 Jul 2025 (actual)
- Study completion
- 6 Jul 2025 (actual)
- First posted
- 26 Jun 2018 (actual)
- Results
- Posted 25 Sep 2026
Clinical summary
The research question as the sponsor registered it. This describes what the study plans to test, not what it found.
A Phase 1/2a study to assess the safety, tolerability, PK and biological activity of CCS1477 in patients with metastatic castration resistant prostate cancer, metastatic breast cancer, non-small cell lung cancer or advanced solid tumours.
Detailed description
The Steering Committee closed selected cohorts, in accordance with its responsibilities, after findings from earlier cohorts indicated that further evaluation of those cohorts was no longer warranted. The remaining cohorts were completed as specified in the protocol. Therefore, the study was considered completed.
Study design
- Primary purpose
- Treatment
- Allocation
- Non-randomised
- Intervention model
- Sequential
- Masking
- None (open label)
- Number of arms
- 8
- Model description
- The RP2D/MTD dose will be determined in Part A. Parts B-H will run in parallel after the completion of Part A.
| Arm | Type | Receives |
|---|---|---|
| CCS1477 dose escalation - mCRPC | Experimental | Drug: CCS1477CCS1477 monotherapy in patients with mCRPC |
| CCS1477 expansion phase - mCRPC | Experimental | Drug: CCS1477CCS1477 monotherapy in patients with mCRPC |
| CCS1477 and abiraterone acetate, combination dose finding and expansion - mCRPC | Experimental | Drug: CCS1477, Drug: Abiraterone acetateCCS1477 plus abiraterone acetate in patients with mCRPC |
| CCS1477 and enzalutamide, combination dose finding and expansion - mCRPC | Experimental | Drug: CCS1477, Drug: EnzalutamideCCS1477 plus enzalutamide in patients with mCRPC |
| CCS1477 Monotherapy - Solid tumours | Experimental | Drug: CCS1477CCS1477 expansion phase in patients with advanced solid tumours with molecular markers which may indicate potential for response to p300/CBP inhibition |
| CCS1477 and darolutamide, combination dose finding and expansion - mCRPC | Experimental | Drug: CCS1477, Drug: DarolutamideCCS1477 plus darolutamide in patients with mCRPC |
| CCS1477 and olaparib, combination dose finding and expansion - mCRPC and metastatic breast cancer | Experimental | Drug: CCS1477, Drug: OlaparibCCS1477 plus olaparib in patients with mCRPC or metastatic breast cancer. |
| CCS1477 and atezolizumab, combination dose finding and expansion - non-small cell lung cancer | Experimental | Drug: CCS1477, Drug: AtezolizumabCCS1477 plus atezolizumab in patients with non-small cell lung cancer |
Who may qualify
- Ages
- 18 years and older
- Sex
- All
- Healthy volunteers
- Not accepted
- Age groups
- Adult, Older adult
Key inclusion criteria (22 listed)
- Provision of consent
- ECOG performance status 0-1
- Assessable disease (by CT, MRI, bone scan or X-ray)
- Adequate organ function
- Highly effective contraception measures for duration of study
Key exclusion criteria (17 listed)
- Intervention with any chemotherapy, investigational agents or other anti-cancer drugs within 14 days or 5 half-lives of the first dose
- Radiotherapy with a wide field of radiation or to more than 30% of the bone marrow within 4 weeks of the first dose of study treatment
- Major surgical procedure or significant traumatic injury within 4 weeks of the first dose of study treatment
- Strong inhibitors of CYP3A4 or CYP3A4 substrates with a narrow therapeutic range taken within 2 weeks of the first dose of study treatment
- Strong inducers of CYP3A4 within 4 weeks of the first dose of study treatment
Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.
Interventions
| Intervention | Type | Arms |
|---|---|---|
| CCS1477Capsules, oral | Drug | CCS1477 Monotherapy - Solid tumours, CCS1477 and abiraterone acetate, combination dose finding and expansion - mCRPC, CCS1477 and atezolizumab, combination dose finding and expansion - non-small cell lung cancer, CCS1477 and darolutamide, combination dose finding and expansion - mCRPC, CCS1477 and enzalutamide, combination dose finding and expansion - mCRPC, CCS1477 and olaparib, combination dose finding and expansion - mCRPC and metastatic breast cancer, CCS1477 dose escalation - mCRPC, CCS1477 expansion phase - mCRPC |
| Abiraterone acetateAbiraterone acetate 500mg tablets plus prednisone/prednisolone | Drug | CCS1477 and abiraterone acetate, combination dose finding and expansion - mCRPC |
| EnzalutamideEnzalutamide 40mg capsules/tablets | Drug | CCS1477 and enzalutamide, combination dose finding and expansion - mCRPC |
| Darolutamide300mg tablets | Drug | CCS1477 and darolutamide, combination dose finding and expansion - mCRPC |
| Olaparib150mg tablets | Drug | CCS1477 and olaparib, combination dose finding and expansion - mCRPC and metastatic breast cancer |
| Atezolizumab840mg/14ml concentrate for solution for infusion vials | Drug | CCS1477 and atezolizumab, combination dose finding and expansion - non-small cell lung cancer |
Primary outcome
Number of Participants With Treatment-Emergent Adverse Events (TEAEs), Serious TEAEs and TEAEs Leading to Withdrawal
Time frame: From signing informed consent until the end of the follow-up period (Up to 363 weeks)
Adverse Event (AE) was defined any untoward medical occurrence in a participant administered with a study intervention, which does not necessarily have a causal relationship with the treatment. Serious AE (SAE) was defined AE that resulted in any of the following outcomes: death; life threatening; persistent/significant disability/incapacity; initial/prolonged inpatient hospitalization; congenital anomaly/birth defect. TEAEs: TEAEs were defined as those events with onset dates/time occurring after study intervention administration or events that worsen after study intervention administration. TEAEs included serious TEAEs and non-serious TEAEs. Number of participants with TEAEs leading to withdrawal of study intervention was also reported.
Number of Participants With Worst Shift in Laboratory Data-Hematology According to Common Terminology Criteria for Adverse Events (CTCAE)-Version 5 Grades
Time frame: From first dose of study drug in Cycle 1 up to and including 28 days after last dose of study intervention (Up to 363 weeks) (Cycle length was 4 weeks for Cycles 1-6 and 6 weeks for Cycle 7 and subsequent cycles.)
Adverse events were graded according to the National Cancer Institute (NCI) Common Terminology Criteria for Adverse Events (CTCAE) Version 5.0, where Grade 1 = mild, Grade 2 = moderate, Grade 3 = severe, Grade 4 = life-threatening, and Grade 5 = death related to the adverse event. Number of participants with worst shift in hematology according to Common Terminology Criteria for Adverse Events (CTCAE) grades were reported.
Number of Participants With Worst Shift in Laboratory Data-Biochemistry According to Common Terminology Criteria for Adverse Events (CTCAE)-Version 5 Grades
Time frame: From first dose of study drug in Cycle 1 up to and including 28 days after last dose of study intervention (Up to 363 weeks) (Cycle length was 4 weeks for Cycles 1-6 and 6 weeks for Cycle 7 and subsequent cycles.)
Adverse events were graded according to the National Cancer Institute (NCI) Common Terminology Criteria for Adverse Events (CTCAE) Version 5.0, where Grade 1 = mild, Grade 2 = moderate, Grade 3 = severe, Grade 4 = life-threatening, and Grade 5 = death related to the adverse event. Number of participants with worst shift in biochemistry according to Common Terminology Criteria for Adverse Events (CTCAE) grades were reported.
Number of Participants With Clinically Significant Change From Baseline in Laboratory Parameters - Urinalysis
Time frame: From first dose of study drug in Cycle 1 up to and including 28 days after last dose of study intervention (Up to 363 weeks) (Cycle length was 4 weeks for Cycles 1-6 and 6 weeks for Cycle 7 and subsequent cycles.)
The urinalysis measurements included glucose, protein and blood. Number of participants with clinically significant changes from baseline in urinalysis values were reported. Clinically Significance was decided by investigator.
Number of Participants With Clinically Significant Change From Baseline in Vital Signs
Time frame: From first dose of study drug in Cycle 1 up to and including 28 days after last dose of study intervention (Up to 363 weeks) (Cycle length was 4 weeks for Cycles 1-6 and 6 weeks for Cycle 7 and subsequent cycles.)
The vital signs measurements included blood pressure, heart rate, respiration rate and temperature. Number of participants with clinically significant changes from baseline in vital signs values were reported. Clinically Significance was decided by investigator.
Number of Participants With Worst Shift in QTcF According to Common Terminology Criteria for Adverse Events (CTCAE)-Version 5 Grades
Time frame: From first dose of study drug in Cycle 1 up to and including 28 days after last dose of study intervention (Up to 363 weeks) (Cycle length was 4 weeks for Cycles 1-6 and 6 weeks for Cycle 7 and subsequent cycles)
Twelve-lead Electrocardiograms (ECGs) were obtained after the participant was in semi-supine for 5 minutes. Three ECGs were taken at each timepoint at about 1-minute intervals. QTcF was calculated using the Fridericia formula: QTcF = QT ÷ RR^(1/3), where QT is the measured QT interval in milliseconds and RR is the interval between two consecutive R waves on the ECG expressed in seconds. It was categorized as less than equal to (<=) 450 milliseconds (msec), more than (>) 450 to <=480 msec, > 480 to <= 500 msec and > 500 msec.
7 secondary outcomes
Best Percentage Change From Baseline in Prostate Specific Antigen (PSA) Response in Participants With Metastatic Castration Resistant Prostate Cancer (mCRPC)
Time frame: At Baseline - Cycle 1 - Day 1, Day 8, Day 15, Day 22 and Day 1 of every cycle from cycle 2 onwards until treatment discontinuation (Up to 363 weeks) (Cycle length was 4 weeks for Cycles 1-6 and 6 weeks for Cycle 7 and subsequent cycles.)
Number of Participants With CTC Response
Time frame: From Baseline - Day 1 Cycle 1 (Predose), Day 1 Cycle 2, Day 1 Cycle 3, Day 1 Cycle 5 up to disease progression or treatment discontinuation (Up to 363 weeks) (Cycle length was 4 weeks for Cycles 1-6 and 6 weeks for Cycle 7 and subsequent cycles)
Objective Response Rate (ORR) According to Response Evaluation Criteria in Solid Tumors (RECIST) Version 1.1
Time frame: From day of study intervention in Cycle 1 until progression or censoring date in the absence of progression (Up to 363 weeks) (Cycle length was 4 weeks for Cycles 1-6 and 6 weeks for Cycle 7 and subsequent cycles)
Radiological Progression Free Survival (rPFS) According to Response Evaluation Criteria in Solid Tumors (RECIST) Version 1.1
Time frame: From day of study intervention in Cycle 1 until progression or censoring date in the absence of progression (Up to 363 weeks) (Cycle length was 4 weeks for Cycles 1-6 and 6 weeks for Cycle 7 and subsequent cycles)
Overall Survival (OS)
Time frame: From start of treatment until death (Up to 363 weeks)
Maximum Observed Plasma Concentration (Cmax)
Time frame: Cycle 1 Day 1 and Cycle 2 Day 3 (Cycle length was 4 weeks)
Area Under the Plasma Concentration-Time Curve From Time Zero to Infinity (AUC0-24)
Time frame: Cycle 1 Day 1 and Cycle 2 Day 3 (Cycle length was 4 weeks)
Results and safety
Loading the posted results from ClinicalTrials.gov…
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 25 Sep 2026.
- Posted resultsParticipant flow, baseline, all outcome measures and adverse events.
- Derived from this study: PubMed 36826464Caligiuri M, Williams GL, Castro J, Battalagine L, Wilker E, Yao L, Schiller S, Toms A, Li P, Pardo E, Graves B, Azofeifa J, Chicas A, Herbertz T, Lai M, Basken J, Wood KW, Xu Q, Guichard SM. FT-6876, a Potent and Selective Inhibitor of CBP/p300, is Active in Preclinical Models of Androgen Receptor-Positive Breast Cancer. Target Oncol. 2023 Mar;18(2):269-285. doi: 10.1007/s11523-023-00949-7. Epub 2023 Feb 24.
- Derived from this study: PubMed 36125208Eickhoff N, Bergman AM, Zwart W. Homing in on a Moving Target: Androgen Receptor Cistromic Plasticity in Prostate Cancer. Endocrinology. 2022 Oct 11;163(11):bqac153. doi: 10.1210/endocr/bqac153.
- Individual participant dataSharing planned: No
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Referral and contact
AzTrials does not enrol participants or take referrals. Contact the study team or a site listed below; they decide who can take part. This study is not recruiting at the moment.
Johann de Bono, MD principal investigator
Royal Marsden NHS Foundation Trust
19 sites in 6 countries: see every site and its status.
Questions about this trial
What is this clinical trial studying?
A Phase 1/2 study testing CCS1477, Abiraterone acetate and Enzalutamide in people with Metastatic Castration-Resistant Prostate Cancer and Metastatic Breast Cancer, run by CellCentric Ltd. at 19 sites in 6 countries.
The full registered description is in the About this study section and the official record.
Who may be eligible to take part?
The sponsor lists 22 inclusion and 17 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.
Is this clinical trial currently recruiting?
The record says: finished, as of the sponsor's last update on 25 Sep 2026. Status can change between updates, so confirm with the study contact before making plans.
Where is the study taking place?
The record lists 19 sites in United Kingdom, France, United States, Spain, Netherlands and 1 more country. Whether a site is taking part right now should be confirmed with that site. See every site.
What are the possible benefits and risks?
They depend on the study and the treatment, and no study can promise a benefit. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.
What does this combined phase mean?
Phase 1 studies test a treatment in a small group of people for the first time or in a new way, mainly to check safety and find the right dose.
Phase 2 studies give the treatment to a larger group to see whether it has the intended effect and to keep checking safety.
Not every study follows the same path, and some studies (observational studies, device studies) have no phase.
Are results available for this study?
Yes. Results are posted in the registry (first posted 25 Sep 2026). A summary is in the For doctors view, and the full results are on ClinicalTrials.gov.
How can a doctor refer a patient or contact the research team?
The record lists no contact. The official record names the sponsor, who can be asked directly. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
Number of Participants With Treatment-Emergent Adverse Events (TEAEs), Serious TEAEs and TEAEs Leading to Withdrawal (time frame: From signing informed consent until the end of the follow-up period (Up to 363 weeks)). The study lists 6 primary outcomes in all. It is what the study was designed to measure, not a finding.
Where can I read the original study information?
On the ClinicalTrials.gov record for NCT03568656, which also lists 2 linked publications.
Does a listing mean the treatment is approved or proven to work?
No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.
How often is this information updated?
AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 25 Sep 2026.