CompletedNCT01075308Updated Aug 4, 2023

SB939 in Treating Patients With Recurrent or Metastatic Prostate Cancer

A Phase 2 interventional study of HDAC inhibitor SB939 in Prostate Cancer, sponsored by NCIC Clinical Trials Group. Completed at 7 sites in Canada. Open to male participants aged 18 Years to 120 Years. Per ClinicalTrials.gov, last updated 2023-08-04.

Sponsored by NCIC Clinical Trials Group · Phase 2, Interventional, and Treatment

Phase: Phase 2
Study type: Interventional
Enrollment: 32
Allocation: Not applicable
Ages: 18 Years to 120 Years
Sex: Male

Study summary

RATIONALE: SB939 may stop the growth of tumor cells by blocking some of the enzymes needed for cell growth.

PURPOSE: This phase II trial is studying how well SB939 works in treating patients with recurrent or metastatic prostate cancer.

Read the detailed description

OBJECTIVES:

Primary

To determine the efficacy, as measured by PSA response and progression-free survival, of HDAC inhibitor SB939 in patients with recurrent or metastatic castration-resistant prostate cancer.

Secondary

To determine the objective response and response duration in patients with measurable disease at baseline.
To determine the tolerability and toxicity of this drug in these patients.
To determine the number of circulating tumor cells at baseline and after 6 weeks (and 12 weeks if patient is still on study treatment).
To explore potential molecular factors predictive of response by assessment of archival prostate tumor tissue.
To explore ERG and PTEN expression on circulating tumor cells as a potential prognostic and predictive marker for response to this drug.
To determine time to PSA and time to objective progression in these patients.

OUTLINE: This is a multicenter study.

Patients receive oral HDAC Inhibitor SB939 once daily on days 1, 3, 5, 8, 10, 12, 15, 17, and 19. Treatment repeats every 4 weeks for up to 12 courses in the absence of disease progression or unacceptable toxicity.

Blood samples are collected periodically for correlative studies. Blood samples and Archival tumor tissue are analyzed for TMPRSS2-ERG fusion and PTEN deletion status by FISH; TMPRSS2-ERG fusion by RT-PCR; and for the number of circulating tumor cells.

After completion of study therapy, patients are followed up at 4 weeks and then every 3 months thereafter.

Conditions studied

Prostate Cancer

Browse trials for

Prostatic Neoplasms 6,367

Keywords

hormone-resistant prostate cancer
recurrent prostate cancer
stage IV prostate cancer
stage III prostate cancer
adenocarcinoma of the prostate

In context

Prostatic Neoplasms

6,367 studies on the registry are indexed under Prostatic Neoplasms; 1,397 are open to participants now.

This study's enrollment of 32 is below the median of 58 across 4,821 interventional studies indexed under Prostatic Neoplasms.

Browse Prostatic Neoplasms studies →

Lead sponsor

NCIC Clinical Trials Group is the lead sponsor of 114 studies on the registry; none are open to participants now.

Of its 27 completed or terminated interventional studies of FDA-regulated products, 7 (26%) have results posted.

Counted across the registry records on this site, refreshed daily.

Who can participate

Ages eligible: 18 Years to 120 Years
Sexes eligible: Male
Accepts healthy volunteers: No

Eligibility criteria

DISEASE CHARACTERISTICS:

Histologically confirmed adenocarcinoma of the prostate
Presence of clinically and/or radiologically documented disease (target or non-target)
Metastatic or locally recurrent disease for which no curative therapy exists AND for which systemic chemotherapy is indicated due to progression, meeting the following criteria:
- At least two rises in PSA over a reference value OR the development of new metastatic lesions with a stable or rising PSA
  - First rising PSA must be taken at least 1 week after the reference value
  - Third or subsequent PSA must show further increase confirming progression within 2 weeks prior to study enrollment
  - PSA progression must be documented after discontinuation of peripheral antiandrogens (4 weeks for flutamide and 6 weeks for bicalutamide/nilutamide) for patients with documented evidence of progression while receiving peripheral antiandrogens
Medically or surgically castrated by androgen ablation
- Castrate level of testosterone (\< 1.7 nmol/L) must be present for patients undergoing medical androgen ablation
Received prior hormone therapy
- Must have hormone-refractory disease
- Therapy with luteinizing hormone-releasing hormone (LHRH) agonist must continue for patients already receiving this treatment at the time of enrollment
- Patients who discontinued LHRH agonist must restart therapy (if not surgically castrated) and the castrate level of testosterone must be present
PSA ≥ 5 ng/mL
Primary or metastatic tumor tissue available
No documented CNS metastases

PATIENT CHARACTERISTICS:

ECOG performance status 0-1
Life expectancy ≥ 12 weeks
Absolute granulocyte count ≥ 1.5 x 10\^9/L
Platelet count ≥ 100 x 10\^9/L
AST and ALT ≤ 2.5 times upper limit of normal (ULN)
Bilirubin normal
Serum creatinine normal
Potassium normal
Calcium normal
Fertile patients must use effective contraception
QTc ≤ 450 msec
LVEF ≥ 50% by Echo or MUGA scan
Troponin I or T ≤ ULN
Able to take oral medication
No preexisting uncontrolled cardiac condition
No prior myocardial infarction
No history of other malignancies, except adequately treated nonmelanoma skin cancer or other solid tumors curatively treated with no evidence of disease for ≥ 5 years
No gastrointestinal abnormalities (e.g., bowel obstruction or previous gastric resection) that would lead to inadequate absorption of HDAC Inhibitor SB939
No known HIV positivity or hepatitis B or C infections
No chronic medical condition or comorbidity that may increase the risks associated with study participation/study drug administration or may interfere with the interpretation of study results, including any of the following:
- Pulmonary disease
- Active infection
- Psychiatric condition
- Laboratory abnormality

PRIOR CONCURRENT THERAPY:

See Disease Characteristics
At least 4 weeks since prior antiandrogens (6 weeks for bicalutamide)
At least 4 weeks since prior external-beam radiotherapy
- Exceptions may be made for low-dose, non-myelosuppressive radiotherapy
At least 28 days since other prior investigational therapy or anticancer therapy
At least 14 days since prior major surgery and wound healing has occurred
No more than 1 prior chemotherapy regimen allowed and recovered from significant toxicity
No prior strontium
No prior HDAC inhibitors
No current agents (dysrhythmic drugs) with a known risk of Torsades de Pointes
No other concurrent cytotoxic therapy or radiotherapy
No other concurrent investigational therapy

Study design

Phase: Phase 2
Primary purpose: Treatment
Allocation: Not applicable
Intervention model: Single group
Masking: None (open label)
Enrollment: 32 participants (actual)

Study arms

Experimental
SB939
SB939 given orally every other day 3 times a week (i.e. Monday /Wednesday /Friday, or Tuesday /Thursday / Saturday) for 3 consecutive weeks followed by one week off-dosing. A treatment cycle is 4 weeks (28 days).
Drug: HDAC inhibitor SB939

Interventions

DrugHDAC inhibitor SB939
SB939 given orally every other day 3 times a week (i.e. Monday /Wednesday /Friday, or Tuesday /Thursday / Saturday) for 3 consecutive weeks followed by one week off-dosing. A treatment cycle is 4 weeks (28 days).

What researchers measure

Primary outcomes

PSA response
Each patient will have PSA response calculated. Required at the end of every cycle.
Time frame: each cycle
Progression-free survival
Used as an indicator of efficacy, patients with PSA response will have length of progression free survival calculated.
Time frame: end of study

Secondary outcomes

Objective response rate
Patients with measurable disease will have objective response evaluated.
Time frame: every other cycle
Duration of response
Patients with objective response will have duration of response calculated as will be followed until progression/relapse
Time frame: every other cycle
Safety
Toxicity and tolerability will be evaluated
Time frame: each cycle
Change in circulating tumor cells during study compared to baseline
Patients will have on study samples compared to baseline to look for chance in number of CTC.
Time frame: each cycle
Comparison of TMPRSS2-ERG fusion and PTEN deletion in circulating tumor cells
samples will be taken and analyzed each cycle with a comparison made at end of study.
Time frame: each cycle
Comparison of two systems for counting circulating tumor cells
Two different systems will be used to count CTC. Results will be compared at the end of the study for accuracy.
Time frame: end of study

Study locations

7 sites

Tom Baker Cancer Centre
Calgary, Alberta T2N 4N2, Canada
Cross Cancer Institute
Edmonton, Alberta T6G 1Z2, Canada
BCCA - Cancer Centre for the Southern Interior
Kelowna, British Columbia V1Y 5L3, Canada
BCCA - Vancouver Cancer Centre
Vancouver, British Columbia V5Z 4E6, Canada
QEII Health Sciences Center
Halifax, Nova Scotia B3H 1V7, Canada
London Regional Cancer Program
London, Ontario N6A 4L6, Canada
Univ. Health Network-Princess Margaret Hospital
Toronto, Ontario M5G 2M9, Canada

References and documents

Publications

Eigl BJ, North S, Murray N, Heng DYC, Winquist E, Powers J, Walsh WR, Eisenhauer E, Squire J, Cox M, Chi KN. A Phase II Study of SB939 in Patients with Recurrent or Metastatic Castration Resistant Prostate Cancer (CRPC). AACR Mol Cancer Tehr 10[11 Suppl; abstr A211]. 2011
Eigl BJ, North S, Murray N, Heng DYC, Winquist E, Powers J, Walsh WR, Eisenhauer E, Squire J, Cox M, Chi KN. A Phase II Study of SB939 in Patients with Recurrent or Metastatic Castration Resistant Prostate Cancer (CRPC). Canadian Cacner Research Conference. 2011.
Eigl BJ, North S, Winquist E, Finch D, Wood L, Sridhar SS, Powers J, Good J, Sharma M, Squire JA, Bazov J, Jamaspishvili T, Cox ME, Bradbury PA, Eisenhauer EA, Chi KN. A phase II study of the HDAC inhibitor SB939 in patients with castration resistant prostate cancer: NCIC clinical trials group study IND195. Invest New Drugs. 2015 Aug;33(4):969-76. doi: 10.1007/s10637-015-0252-4. Epub 2015 May 19. PubMed 25983041 ↗

Individual participant data

Plan to share: No

Updates

Tracking since Sep 25, 2026

No changes since tracking began. The registry record was last updated on Aug 4, 2023, before this site started recording changes on Sep 25, 2026. Its history is on ClinicalTrials.gov ↗

Registry details

Key details

Study ID: NCT01075308
Lead sponsor: NCIC Clinical Trials Group
Collaborators: S*BIO
Responsible party: Sponsor
First posted: Feb 25, 2010
Start date: Jun 28, 2010
Primary completion: Jan 5, 2015
Completion: Feb 13, 2015
Last update: Aug 4, 2023

Study contacts

Kim N. Chi, MD

study chair · British Columbia Cancer Agency

Bernhard Eigl, MD, FRCPC

study chair · Tom Baker Cancer Centre - Calgary

Oversight

Data monitoring committee: Yes
FDA-regulated drug: No
FDA-regulated device: No

View the source record on ClinicalTrials.gov ↗

Not currently enrolling

This study is completed, as verified in Apr 2020. You cannot join it, but the record below documents what was studied.

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