Breast CancerNCT07897344
Short-Term Reduced Dietary Protein in ER+/HER2- Breast Cancer Patients During Neoadjuvant Chemotherapy
A study testing Dietary Protein Intervention in people with Breast Cancer and Hormone Receptor Positive / HER2-negative Breast Cancer, run by Josephine Connolly-Schoonen at 1 site in United States.
Trial summary
This study will examine if a short-term, reduced protein diet for the 3-day period prior to and on the day of each of the first 4 chemotherapy cycles and 4 days prior to primary breast surgery is well tolerated and adhered to by patients with stage II or III estrogen receptor positive (ER+) human epidermal growth… Read more about this study
- Who is it for?
- Ages 18 to 75 years, women only
- Conditions the study is for
- Breast Cancer, Hormone Receptor Positive / HER2-negative Breast Cancer
- What is being tested?
- Dietary Protein Intervention
- Could I receive a placebo?
- No, everyone receives an active treatment
- How many people
- 15 participants
- Where
- 1 siteUnited States
- Study dates
- 3 Nov 2026to 30 Apr 2029
- Phase
- Interventional
- Are there results?
- Not yet: the study is under way
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 to 75 years
- Women only
- No healthy volunteers
- Adult, Older adult
Who may be able to join
- 18-75 years of age at time of consent
- Stage II or III ER+ HER2- breast cancer patients scheduled to receive standard of care neoadjuvant chemotherapy
- Willingness to consume study foods exclusively during the 20 days of prescribed diet
Who cannot join
- Any food allergy that may result in anaphylactic response or death (due to possible food allergen cross-contamination in the metabolic kitchen)
- Habitual low protein intake, less than or equal to 1.0 g per kilogram adjusted body weight, based on a screening dietary habits questionnaire score
- Vegans or vegetarians that consume dairy and or eggs
- Pregnant or breastfeeding at the time of screening
- Significant mental illness presenting challenges to follow directions and consume the controlled protein diet exclusively
- Body mass index less than or equal to 18 kilograms over meter squared or greater than 35 kilograms over meter squared
- Participating in another study with a diet intervention
Trial locations and contacts
1 site in 1 country. Contact the study team or a site near you to ask about taking part.
Stony Brook Cancer Cetner Clinical Research Office contact
United States1 site, 1 recruiting
- Recruiting
Stony Brook Cancer Center
Stony Brook, New York, 11794
Stony Brook University Cancer Clinical Trials Office, 631-728-7425, CancerClinicalTrials@stonybrookmedicine.edu
Josephine Connolly-Schoonen, PhD, RD
About this study
Official title: A Pilot Trial of Controlled Feeding With Reduced Dietary Protein in Patients With Estrogen Receptor Positive, Human Epidermal Growth Factor Receptor 2 Negative Breast Cancer Receiving Neoadjuvant Chemotherapy
This study will examine if a short-term, reduced protein diet for the 3-day period prior to and on the day of each of the first 4 chemotherapy cycles and 4 days prior to primary breast surgery is well tolerated and adhered to by patients with stage II or III estrogen receptor positive (ER+) human epidermal growth factor receptor negative (HER2-) breast cancer (BC) receiving neoadjuvant chemotherapy (NAC).
Read the detailed description
There has been recent interest in the potential anti-cancer effects of nutrition interventions, although little is known about how individual patients' diets can impact the tumor microenvironment, and potentially patient outcomes. This is despite long-standing patient and healthcare provider interest in this type of adjunctive therapy. Therein lies a significant opportunity to develop nutritional recommendations that could exert antitumor effects with minimal, if any, side effects. To meet this opportunity, dietary alterations in cancer patients have been implemented in a surprisingly small number of studies, including the use of ketogenic and fasting-mimicking diets. Although findings from these trials suggest some modest benefit, such extreme alterations proved difficult for patients to adhere to, thus making them impractical for wide-spread use. Studies in humans show that high protein intake significantly increases the likelihood of dying from cancer, and work in rodents shows that feeding a high protein diet enhances carcinogenesis, suggesting that limiting protein intake may have anticancer benefits. Accordingly, investigators at Stony Brook University and others have shown that reducing protein consumption slows tumor growth, enhances anti-tumor immunity and improves the efficacy of anticancer therapy in murine models. These effects likely result from restricting the availability of tumor growth promoting amino acids. However, the impact of lowering protein intake on the biology of patients' tumors is unknown.
Investigators at Stony Brook University have already established a method to reduce protein intake in healthy humans demonstrating strong adherence and correlated biological changes. Positive findings from this trial would justify larger scale randomized controlled feeding trials to evaluate clinical outcomes including pathologic response, treatment tolerance, immune cell infiltration, and overall survival with this intervention. This line of investigation has the potential to provide the first evidence that intermittent dietary protein reduction is a safe, low-cost method to impede tumor growth, optimize response to anti-tumor therapies and improve patient outcomes.
- Being tested
- Dietary Protein Intervention
- Keywords
- Diet, Protein, Breast cancer, Hormone Receptor Positive / HER2-negative Breast Cancer, Neoadjuvant chemotherapy, Estrogen receptor positive
- Medical subject headings
- Breast Neoplasms
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
Dietary Protein InterventionOther
Also called Dietary modification, Nutrition intervention, Intervention, dietary, Nutritional intervention
Consume an intermittent, reduced protein diet for a total of 20 feeding days over the course of neoadjuvant treatment (at the time of the first four chemotherapy cycles and prior to surgery)
| Study group | Role | What they receive |
|---|---|---|
| Intermittent Reduced Dietary Protein Intervention | Experimental | Patients will receive an intermittent, reduced protein diet for the 3-day period prior to and on the day of each of the first 4 chemotherapy cycles and 4 days prior to primary breast surgery. Receives: Other: Dietary Protein Intervention |
What is being measured
The primary outcome is the main question the study is designed to answer.
Feasibility of completing the intermittent, reduced protein diet intervention
Percent of enrolled patients that complete the intervention (accept the interventional diet for 3 days before and day of chemotherapy and complete the diet intake surveys for at least 4 of the 5 diet periods) - Measured by uploaded/self-reported meal consumption pictures.
Measured: Immediately after the intervention/pre-surgery
Recruitment of patients receiving neoadjuvant chemotherapy for breast cancer into an intermittent, reduced protein diet intervention
Enrollment rate, defined as the percentage of patients offered participation who enroll in the study
Measured: 18 months
Secondary outcomes (12)
Adherence to the intermittent, reduced protein diet among patients receiving neoadjuvant chemotherapy for breast cancer
Percent of patients who consume less or equal to 0.9 g of protein per kilogram of body weight over the intervention period - measured by uploaded/self-reported meal consumption pictures.
Measured: Up to 20 intervention days
Safety of an intermittent, reduced protein diet - weight change
Longitudinal weight change, measured by the InBody 380 device, in patients receiving neoadjuvant chemotherapy for breast cancer
Measured: Day of surgery/before surgery
Safety of an intermittent, reduced protein diet - muscle mass change
Longitudinal muscle mass change, measured by the InBody 380 device, in patients receiving neoadjuvant chemotherapy for breast cancer
Measured: Post-cycle 4 chemotherapy medical oncology visit (each cycle is 21 days)
Safety of an intermittent, reduced protein diet - fat mass change
Longitudinal fat mass change, measured by the InBody 380 device, in patients receiving neoadjuvant chemotherapy for breast cancer
Measured: Baseline, Cycle 4 Day 1 (each cycle is 21 days) and Preoperative evaluation (average of 6 months)
Safety of an intermittent, reduced protein diet - handgrip strength change
Longitudinal handgrip strength change, measured by the Jamar dynamometer, in patients receiving neoadjuvant chemotherapy for breast cancer
Measured: Baseline, Cycle 4 Day 1 (each cycle is 21 days) and Preoperative evaluation (average of 6 months)
Safety of an intermittent, reduced protein diet - frequency of post-operative complications
Number of post-operative complications in breast cancer patients receiving neoadjuvant chemotherapy, assessed by chart review
Measured: One month after primary breast surgery
Safety of an intermittent, reduced protein diet - frequency of episodes of CTCAE greater than or equal to 3 non-hematologic toxicities
Number of episodes of CTCAE greater than or equal to 3 non-hematologic toxicity in patients receiving neoadjuvant chemotherapy for breast cancer, assessed by chart review
Measured: Chemotherapy Cycle 1 Day 1 to one day before surgery (each cycle is 21 days)
Safety of an intermittent, reduced protein diet - frequency of patients who experience at least one CTCAE greater than or equal to 3 non-hematologic toxicities
Percent of patients who experience at least one CTCAE greater than or equal to 3 non-hematologic toxicity, assessed by chart review
Measured: Chemotherapy Cycle 1 Day 1 through chemotherapy Cycle 4 Day 0 (each cycle is 21 days)
Safety of an intermittent, reduced protein diet - frequency of dose reduction or delay in chemotherapy
Number of episodes of dose reductions or delays in chemotherapy in patients receiving neoadjuvant treatment for breast cancer, assessed by chart review
Measured: Chemotherapy Cycle 1 Day 1 through chemotherapy Cycle 4 Day 0 (each cycle is 21 days)
Tolerability of an intermittent, reduced protein diet - change in domain-specific self-reported gastrointestinal symptoms
Change in self-reported Gastrointestinal symptoms measured by survey tool - (Patient-Reported Outcomes Measurement Information System Gastrointestinal (PROMIS-GI)).
The PROMIS-GI is a standardized set of symptom scales. It evaluates 61 specific items across 8 domains: belly pain, bowel incontinence, constipation, diarrhea, disrupted swallowing, gas/bloating, gastroesophageal reflux, and nausea/vomiting.
Scores are calibrated using standardized T-scores with a mean of 50 and a standard deviation of 10 in the U.S. general population. A higher score denotes more severe or frequent GI symptoms.
Measured: Baseline, Cycle 1 Day 1 (each cycle is 21 days), Cycle 4 Day 1, and Preoperative evaluation (average of 6 months)
Tolerability of an intermittent, reduced protein diet - change in self-reported total gastrointestinal symptoms
Change in self-reported gastrointestinal symptom scores measured by survey tool - (Patient-Reported Outcomes Measurement Information System Gastrointestinal (PROMIS-GI)).
The PROMIS-GI is a standardized set of symptom scales. It evaluates 61 specific items across 8 domains: belly pain, bowel incontinence, constipation, diarrhea, disrupted swallowing, gas/bloating, gastroesophageal reflux, and nausea/vomiting.
Scores are calibrated using standardized T-scores with a mean of 50 and a standard deviation of 10 in the U.S. general population. A higher score denotes more severe or frequent GI symptoms.
Measured: Baseline, Cycle 1 Day 1 (each cycle is 21 days), Cycle 4 Day 1, and Preoperative evaluation (average of 6 months)
Tolerability of an intermittent, reduced protein diet - change in subjective global assessment score
Change in subjective global assessment score measured by survey tool (Patient Generated Subjective Global Assessment (PG-SGA)).
The PG-SGA is a 9-questions survey used to screen for malnutrition. It is a validated instrument that evaluates weight history, food intake, nutrition-related symptoms, functional status, disease-related metabolic stress, and physical findings to determine malnutrition risk and nutritional status.
The PG-SGA total score ranges from 0 upward, with higher scores indicating greater nutritional risk and increased need for nutrition-related intervention.
Measured: Baseline, Cycle 1 Day 1 (each cycle is 21 days), Cycle 4 Day 1, and Preoperative evaluation (average of 6 months)
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted27 Oct 2026
- Study start3 Nov 2026
- Primary completion30 Oct 2028 (estimated)
- Study completion30 Apr 2029 (estimated)
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Other trials for Breast 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 N/A
- Primary purpose
- Treatment
- Allocation
- Not applicable
- Intervention model
- Single group
- Model description
- Single arm pilot study
- Masking
- None (open label)
- Enrolment
- 15 participants (estimated)
Sponsor and investigators
- Lead sponsor
- Josephine Connolly-Schoonen
- Sponsor type
- University, hospital or other
- Responsible party
- Sponsor-investigator, Josephine Connolly-Schoonen, Stony Brook University
- Investigators
- Josephine Connolly-Schoonen, PhD, RD, Principal investigator, Stony Brook University - Family, Population and Preventive Medicine
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT07897344
- Sponsor's protocol ID
- SBU-BC-RPD
- Status last verified
- Oct 2026
- First submitted
- 13 Aug 2026
- Last updated
- 6 Nov 2026
- Results posted
- No
- Data monitoring committee
- Yes
- FDA-regulated drug
- No
- FDA-regulated device
- No
- Individual data sharing
- No
Study at a glance
From the registry record, last updated by the sponsor on 6 Nov 2026. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- A Pilot Trial of Controlled Feeding With Reduced Dietary Protein in Patients With Estrogen Receptor Positive, Human Epidermal Growth Factor Receptor 2 Negative Breast Cancer Receiving Neoadjuvant Chemotherapy
- ClinicalTrials.gov ID
- NCT07897344
- Acronym / sponsor ID
- SBU-BC-RPD
- Keywords
- Diet, Protein, Breast cancer, Hormone Receptor Positive / HER2-negative Breast Cancer, Neoadjuvant chemotherapy, Estrogen receptor positive
- Study type
- Interventional
- Recruitment status
- Recruiting
- Enrolment
- 15 participants (estimated)
- Lead sponsor
- Josephine Connolly-SchoonenUniversity, hospital or other
- Study start
- 3 Nov 2026 (actual)
- Primary completion
- 30 Oct 2028 (estimated)
- Study completion
- 30 Apr 2029 (estimated)
- First posted
- 27 Oct 2026 (actual)
- Results
- Not posted in the source record
Clinical summary
The research question as the sponsor registered it. This describes what the study plans to test, not what it found.
This study will examine if a short-term, reduced protein diet for the 3-day period prior to and on the day of each of the first 4 chemotherapy cycles and 4 days prior to primary breast surgery is well tolerated and adhered to by patients with stage II or III estrogen receptor positive (ER+) human epidermal growth factor receptor negative (HER2-) breast cancer (BC) receiving neoadjuvant chemotherapy (NAC).
Detailed description
There has been recent interest in the potential anti-cancer effects of nutrition interventions, although little is known about how individual patients' diets can impact the tumor microenvironment, and potentially patient outcomes. This is despite long-standing patient and healthcare provider interest in this type of adjunctive therapy. Therein lies a significant opportunity to develop nutritional recommendations that could exert antitumor effects with minimal, if any, side effects. To meet this opportunity, dietary alterations in cancer patients have been implemented in a surprisingly small number of studies, including the use of ketogenic and fasting-mimicking diets. Although findings from these trials suggest some modest benefit, such extreme alterations proved difficult for patients to adhere to, thus making them impractical for wide-spread use. Studies in humans show that high protein intake significantly increases the likelihood of dying from cancer, and work in rodents shows that feeding a high protein diet enhances carcinogenesis, suggesting that limiting protein intake may have anticancer benefits. Accordingly, investigators at Stony Brook University and others have shown that reducing protein consumption slows tumor growth, enhances anti-tumor immunity and improves the efficacy of anticancer therapy in murine models. These effects likely result from restricting the availability of tumor growth promoting amino acids. However, the impact of lowering protein intake on the biology of patients' tumors is unknown.
Investigators at Stony Brook University have already established a method to reduce protein intake in healthy humans demonstrating strong adherence and correlated biological changes. Positive findings from this trial would justify larger scale randomized controlled feeding trials to evaluate clinical outcomes including pathologic response, treatment tolerance, immune cell infiltration, and overall survival with this intervention. This line of investigation has the potential to provide the first evidence that intermittent dietary protein reduction is a safe, low-cost method to impede tumor growth, optimize response to anti-tumor therapies and improve patient outcomes.
Study design
- Primary purpose
- Treatment
- Allocation
- Not applicable
- Intervention model
- Single group
- Masking
- None (open label)
- Number of arms
- 1
- Model description
- Single arm pilot study
| Arm | Type | Receives |
|---|---|---|
| Intermittent Reduced Dietary Protein Intervention | Experimental | Other: Dietary Protein InterventionPatients will receive an intermittent, reduced protein diet for the 3-day period prior to and on the day of each of the first 4 chemotherapy cycles and 4 days prior to primary breast surgery. |
Who may qualify
- Ages
- 18 to 75 years
- Sex
- Female only
- Healthy volunteers
- Not accepted
- Age groups
- Adult, Older adult
Key inclusion criteria (3 listed)
- 18-75 years of age at time of consent
- Stage II or III ER+ HER2- breast cancer patients scheduled to receive standard of care neoadjuvant chemotherapy
- Willingness to consume study foods exclusively during the 20 days of prescribed diet
Key exclusion criteria (7 listed)
- Any food allergy that may result in anaphylactic response or death (due to possible food allergen cross-contamination in the metabolic kitchen)
- Habitual low protein intake, less than or equal to 1.0 g per kilogram adjusted body weight, based on a screening dietary habits questionnaire score
- Vegans or vegetarians that consume dairy and or eggs
- Pregnant or breastfeeding at the time of screening
- Significant mental illness presenting challenges to follow directions and consume the controlled protein diet exclusively
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 |
|---|---|---|
| Dietary Protein InterventionAlso: Dietary modification, Nutrition intervention, Intervention, dietary, Nutritional interventionConsume an intermittent, reduced protein diet for a total of 20 feeding days over the course of neoadjuvant treatment (at the time of the first four chemotherapy cycles and prior to surgery) | Other | Intermittent Reduced Dietary Protein Intervention |
Primary outcome
Feasibility of completing the intermittent, reduced protein diet intervention
Time frame: Immediately after the intervention/pre-surgery
Percent of enrolled patients that complete the intervention (accept the interventional diet for 3 days before and day of chemotherapy and complete the diet intake surveys for at least 4 of the 5 diet periods) - Measured by uploaded/self-reported meal consumption pictures.
Recruitment of patients receiving neoadjuvant chemotherapy for breast cancer into an intermittent, reduced protein diet intervention
Time frame: 18 months
Enrollment rate, defined as the percentage of patients offered participation who enroll in the study
12 secondary outcomes
Adherence to the intermittent, reduced protein diet among patients receiving neoadjuvant chemotherapy for breast cancer
Time frame: Up to 20 intervention days
Safety of an intermittent, reduced protein diet - weight change
Time frame: Day of surgery/before surgery
Safety of an intermittent, reduced protein diet - muscle mass change
Time frame: Post-cycle 4 chemotherapy medical oncology visit (each cycle is 21 days)
Safety of an intermittent, reduced protein diet - fat mass change
Time frame: Baseline, Cycle 4 Day 1 (each cycle is 21 days) and Preoperative evaluation (average of 6 months)
Safety of an intermittent, reduced protein diet - handgrip strength change
Time frame: Baseline, Cycle 4 Day 1 (each cycle is 21 days) and Preoperative evaluation (average of 6 months)
Safety of an intermittent, reduced protein diet - frequency of post-operative complications
Time frame: One month after primary breast surgery
Safety of an intermittent, reduced protein diet - frequency of episodes of CTCAE greater than or equal to 3 non-hematologic toxicities
Time frame: Chemotherapy Cycle 1 Day 1 to one day before surgery (each cycle is 21 days)
Safety of an intermittent, reduced protein diet - frequency of patients who experience at least one CTCAE greater than or equal to 3 non-hematologic toxicities
Time frame: Chemotherapy Cycle 1 Day 1 through chemotherapy Cycle 4 Day 0 (each cycle is 21 days)
Safety of an intermittent, reduced protein diet - frequency of dose reduction or delay in chemotherapy
Time frame: Chemotherapy Cycle 1 Day 1 through chemotherapy Cycle 4 Day 0 (each cycle is 21 days)
Tolerability of an intermittent, reduced protein diet - change in domain-specific self-reported gastrointestinal symptoms
Time frame: Baseline, Cycle 1 Day 1 (each cycle is 21 days), Cycle 4 Day 1, and Preoperative evaluation (average of 6 months)
Tolerability of an intermittent, reduced protein diet - change in self-reported total gastrointestinal symptoms
Time frame: Baseline, Cycle 1 Day 1 (each cycle is 21 days), Cycle 4 Day 1, and Preoperative evaluation (average of 6 months)
Tolerability of an intermittent, reduced protein diet - change in subjective global assessment score
Time frame: Baseline, Cycle 1 Day 1 (each cycle is 21 days), Cycle 4 Day 1, and Preoperative evaluation (average of 6 months)
Results and safety
This study is still under way. Results are not available in the source record yet.
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 6 Nov 2026.
- 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.
Stony Brook Cancer Cetner Clinical Research Office contact
Josephine Connolly-Schoonen, PhD, RD principal investigator
Stony Brook University - Family, Population and Preventive Medicine
1 site in 1 country: see every site and its status.
Questions about this trial
What is this clinical trial studying?
A study testing Dietary Protein Intervention in people with Breast Cancer and Hormone Receptor Positive / HER2-negative Breast Cancer, run by Josephine Connolly-Schoonen at 1 site in United States.
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 3 inclusion and 7 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: looking for participants now, as of the sponsor's last update on 6 Nov 2026. Status can change between updates, so confirm with the study contact before making plans.
Where is the study taking place?
The record lists 1 site in United States. 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.
Are results available for this study?
This study is still under way. Results are not available in the source record yet.
How can a doctor refer a patient or contact the research team?
Contact Stony Brook Cancer Cetner Clinical Research Office (631-728-7425, CancerClinicalTrials@stonybrookmedicine.edu), or a site near the patient. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
Feasibility of completing the intermittent, reduced protein diet intervention (time frame: Immediately after the intervention/pre-surgery). The study lists 2 primary outcomes in all. It is what the study was designed to measure, not a finding.
Where can I read the original study information?
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 6 Nov 2026.