Clinical trial NCT01763944: Carbohydrate Restriction and Prostate Cancer Growth
Official title: A Randomized Controlled Clinical Trial of Carbohydrate Restriction Among Men With A Rising PSA After Failed Primary Therapy for Prostate Cancer
Study type: INTERVENTIONAL
Overall status: COMPLETED
Phase: NA
Conditions: Prostate Cancer
Keywords: diet
prostate cancer
carbohydrate
lifestyle
Lead sponsor: Duke University
Sponsor class: OTHER
Collaborators: name: National Institutes of Health (NIH)
name: National Cancer Institute (NCI)
name: Robert C. Atkins Foundation
name: Cedars-Sinai Medical Center
name: Durham VA Medical Center
First posted: 2013-01-09
Enrollment: 83
Sex: MALE
Minimum age (years): 20
Standard ages: ADULT
OLDER_ADULT
Accepts healthy volunteers: no
Allocation: RANDOMIZED
Intervention model: PARALLEL
Primary purpose: TREATMENT

Brief summary: No treatments have been shown to slow prostate cancer progression after radical prostatectomy. We hypothesize that a carbohydrate restricted diet will slow prostate cancer growth. A total of 60 men with a rising prostate-specific antigen (PSA) after failed primary treatment will be recruited and randomized to either a low-carbohydrate diet (\<20 grams carbohydrates/day) or a no-diet control (standard of care) for 6 months. The primary outcome is PSA doubling time.


Eligibility criteria: Inclusion Criteria:

* Received prior radical prostatectomy or definitive local radiation for prostate cancer (either external beam radiation, brachytherapy, or combination)
* PSA within the past 3 months is between 0.4 and 20 if prior radical prostatectomy, or between 3 and 20 ng/ml if prior radiation therapy.
* PSA doubling time (PSADT) \>3 months and \<36 months

  1. Calculated based at least 2 values (at least 0.2) in the prior 2 years with the first and last PSA separated by at least 3 months
  2. Use all values in the last 2 years to calculate PSADT
  3. PSADT calculated while NOT on androgen deprivation therapy (ADT).
  4. If prior ADT use, then documented either A) normal testosterone or B) a testosterone within 50 points of normal and stable (defined as a second testosterone at least 6 weeks later that is equal or lower than the first testosterone) is required before starting to calculate PSADT.
* BMI \>=24 kg/m2
* Willing to be randomized to a no-diet control or a low-carbohydrate diet
* Reads, writes, and understands English

Exclusion Criteria:

* Anticipate needing secondary prostate cancer therapy within the next 6 months (i.e. radiation, or hormonal therapy)
* Current use of weight loss medications including herbal weight loss supplements or enrolled in a diet/weight loss program
* Currently on therapy aimed at lowering testosterone levels (includes gonadotropin-releasing hormone (GnRH) agonist/antagonist, prior bilateral orchiectomy, oral anti-androgens, or 5-alpha reductase inhibitors). Testosterone replacement is allowed but treatment should be stable during the entire study.
* Known distant metastatic disease
* Already consuming a carbohydrate-restricted or vegetarian diet
* Unable or unwilling to adhere to a carbohydrate-restricted dietary intervention
* Weight loss \>5% of body weight in the last 6 months
* Medical comorbidities that in the opinion of the investigator limits the patient's ability to complete this study

Primary outcomes:
measure: PSA doubling time (change in PSA over time)
timeFrame: Baseline, 3 and 6 months
Secondary outcomes:
Other outcomes:
Locations:
city: Los Angeles
country: United States
facility: Cedars-Sinai Medical Center
state: California
city: Durham
country: United States
facility: Duke University Medical Center
state: North Carolina
city: Durham
country: United States
facility: Durham VA Medical Center
state: North Carolina
Study officials:
affiliation: Duke University
name: Pao-Hwa Lin
role: PRINCIPAL_INVESTIGATOR
References:
citation: Lin PH, Howard L, Freedland SJ. Weight loss via a low-carbohydrate diet improved the intestinal permeability marker, zonulin, in prostate cancer patients. Ann Med. 2022 Dec;54(1):1221-1225. doi: 10.1080/07853890.2022.2069853.
citation: Lin PH, Howard L, Freedland SJ. Impact of Low Carbohydrate Diet on Self-Report Fatigue and Weakness in Prostate Cancer Patients. J Urol. 2021 Sep;206(3):499-501. doi: 10.1097/JU.0000000000001780. Epub 2021 Apr 5. No abstract available.
citation: Freedland SJ, Allen J, Jarman A, Oyekunle T, Armstrong AJ, Moul JW, Sandler HM, Posadas E, Levin D, Wiggins E, Howard LE, Wu Y, Lin PH. A Randomized Controlled Trial of a 6-Month Low-Carbohydrate Intervention on Disease Progression in Men with Recurrent Prostate Cancer: Carbohydrate and Prostate Study 2 (CAPS2). Clin Cancer Res. 2020 Jun 15;26(12):3035-3043. doi: 10.1158/1078-0432.CCR-19-3873. Epub 2020 Feb 27.