Intermittent Negative Pressure for Patients With Diabetic Foot Ulcers (INPRESS) Study

A study testing FlowOx in people with Diabetic Foot Ulcer, run by Lo Zhiwen Joseph at 1 site in Singapore.

Recruiting

Looking for participants now. Contact the study team or a site below to ask about taking part.

Trial summary

The aim of this trial is to investigate the safety and efficacy of 12 weeks treatment with FlowOx, for 1 hour twice daily, when used on patients with diabetic foot ulcers. The main question it aims to answer is whether treatment with FlowOx one hour in the morning and one hour in the evening for 12 weeks can improve… Read more about this study

Who is it for?: Ages 21 to 99 years
Conditions the study is for: Diabetic Foot Ulcer
What is being tested?: FlowOx
Type of treatment: Medical device
Could I receive a placebo?: No, everyone receives an active treatment
How many people: 30 participants
Where: 1 siteSingapore
Study dates: 3 Nov 2025to 2 Nov 2026
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 21 to 99 years
All sexes
No healthy volunteers
Adult, Older adult

Who may be able to join

Provision of signed and dated informed consent form
Stated willingness to comply with all study procedures and availability for the duration of the study
Male or female, aged 21-99.
Diagnosed with diabetes mellitus.
Toe systolic pressure <90 mmHg on the leg to be treated (after revascularization)
Open chronic wound on the foot
Ability to operate the treatment device, and willing to adhere to the study intervention regimen.
Suitable for diabetic limb salvage

Who cannot join

Known allergic reactions to components of the INP device.
Treatment with another investigational intervention within the last 12 weeks prior to inclusion.
Pregnant women or cognitively impaired participants.

Trial locations and contacts

1 site in 1 country. Contact the study team or a site near you to ask about taking part.

Singapore1 site, 1 recruiting

Woodlands Health
Singapore
Zhiwen Joseph Lo, +65 6361 3262, wh.wounds@nhghealth.com.sg
Recruiting

Other trials in Singapore

About this study

Participants will have baseline assessments (i.e. toe pressure measurement and wound area measurement) performed on them and training on the use of FlowOx device will be provided to them in Visit 1. Participants will be tasked to use the FlowOx device (device will be loaned to them) for 1 hour twice daily. A phone call will be conducted 1 week after Visit 1 to follow up on the medical and user-related issues. At Week 6 (Visit 2), participants will be asked to come back for toe pressure and wound area measurement. At Week 12 (Visit 3), end of treatment assessments (i.e toe pressure and wound area measurement) will be performed. Compliance data will be acquired from the FlowOx device.

Their participation in the study will last for 12 weeks. Participants will be asked to use the FlowOx device for one hour, two times a day throughout the study period. They will need to visit the clinic 3 times in the course of the study.

Conditions: Diabetic Foot Ulcer
Being tested: FlowOx
Medical subject headings: Diabetic Foot

What participants receive

What participants receive. In a randomised study each person is assigned to one group by chance.

FlowOxDevice
12 weeks treatment with FlowOx for 1 hour twice daily for 12 weeks

Study groups in NCT07291817
Study group	Role	What they receive
Treatment with FlowOx	Experimental	Not described Receives: Device: FlowOx

What is being measured

The primary outcome is the main question the study is designed to answer.

Change in toe arterial pressure
Toe systolic blood pressure is a commonly used tool to predict wound healing in patients with diabetic foot ulcers.
- Tools used: Photoplethysmography (PPG) Probe/Sensor
- Unit of measure: mmHg
Measured: 12 weeks
Change in wound surface area
Change in wound surface area will be used as an indicator of treatment effect on wound healing.
- Tool used: quantitative measurement of wound surface area
- Unit of measure: cm2
Measured: 12 weeks

Secondary outcomes (3)

Comparison of the primary outcomes (changes in toe arterial pressure and wound healing rate) and post diabetic limb salvage rate between a prospective cohort that is 1:1 propensity-scored matched against a retrospective cohort
The prospective cohort will be 1:1 propensity-scored matched for age, gender and WIfI [wound, ischaemia, foot infection] score on presentation against a retrospective cohort.
Post diabetic limb salvage rate:
- Tools used: Rate of patients who do not undergo major LEA
- Unit of measure: 12-week limb salvage rate
Measured: 12 weeks
Frequency of adverse events
Adverse events and side effects of the treatment will be registered, so that safety assessments can be done during and after the trial.
Measured: 12 weeks
Compliance (mean daily treatment time)
Compliance will be recorded as mean daily treatment time (registered by the device), so that exploratory sub-group analyses on patients with a certain compliance level may be performed.
Measured: 12 weeks

Timeline

From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.

3 Nov 20252 Nov 2026

First posted18 Dec 2025
Study start3 Nov 2025
Primary completion2 Nov 2026 (estimated)
Study completion2 Nov 2026 (estimated)

Resources

Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
Publications (13)Papers the sponsor has linked to this study.
Other trials for Diabetic Foot UlcerStudies 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: Other
Allocation: Not applicable
Intervention model: Single group
Masking: None (open label)
Enrolment: 30 participants (estimated)

IDs, dates and publications

ClinicalTrials.gov ID: NCT07291817
Sponsor's protocol ID: 2024-4641
Acronym: INPRESS
Status last verified: Jul 2026
First submitted: 16 Nov 2025
Last updated: 10 Jul 2026
Results posted: No
FDA-regulated drug: No
FDA-regulated device: No
Individual data sharing: Yes: IPD will be made available on a data repository if required by the publishing journal.

Publications

Yagshyyev S, Hausmann P, Li Y, Kempf J, Zetzmann K, Dessi K, Moosmann O, Almasi-Sperling V, Meyer A, Gerken ALH, Lang W, Rother U. Intermittent negative pressure therapy in patients with no-option chronic limb-threatening ischemia. Vasa. 2023 Nov;52(6):402-408. doi: 10.1024/0301-1526/a001098. Epub 2023 Oct 17.
PubMed 37847243
Herrmann LG, Reid MR. THE CONSERVATIVE TREATMENT OF ARTERIOSCLEROTIC PERIPHERAL VASCULAR DISEASES: PASSIVE VASCULAR EXERCISES (PAVAEX THERAPY). Ann Surg. 1934 Oct;100(4):750-60. doi: 10.1097/00000658-193410000-00016. No abstract available.
PubMed 17856393
Landis E.M HLH. The clinical value of alternate suction and pressure in the treatment of advanced peripheral vascular disease. The American Journal of the Medical Sciences. 1935;189(3):20.
Sinkowitz S, Gottlieb I. Thrombo-angiitis obliterans the conservative treatment by Bier's hyperemia suction apparatus. JAMA.1917;LXVIII(13):961-963.
Sundby OH, Hoiseth LO, Mathiesen I, Jorgensen JJ, Sundhagen JO, Hisdal J. The effects of intermittent negative pressure on the lower extremities' peripheral circulation and wound healing in four patients with lower limb ischemia and hard-to-heal leg ulcers: a case report. Physiol Rep. 2016 Oct;4(20):e12998. doi: 10.14814/phy2.12998.
PubMed 27798353
Sundby OH, Irgens I, Hoiseth LO, Mathiesen I, Lundgaard E, Haugland H, Weedon-Fekjaer H, Sundhagen JO, Sandbaek G, Hisdal J. Intermittent mild negative pressure applied to the lower limb in patients with spinal cord injury and chronic lower limb ulcers: a crossover pilot study. Spinal Cord. 2018 Apr;56(4):372-381. doi: 10.1038/s41393-018-0080-4. Epub 2018 Mar 1.
PubMed 29497177
Hoel H, Pettersen EM, Hoiseth LO, Mathiesen I, Seternes A, Hisdal J. A randomized controlled trial of treatment with intermittent negative pressure for intermittent claudication. J Vasc Surg. 2021 May;73(5):1750-1758.e1. doi: 10.1016/j.jvs.2020.10.024. Epub 2020 Oct 22.
PubMed 33899743
Sundby OH, Hoiseth LO, Mathiesen I, Weedon-Fekjaer H, Sundhagen JO, Hisdal J. The acute effects of lower limb intermittent negative pressure on foot macro- and microcirculation in patients with peripheral arterial disease. PLoS One. 2017 Jun 7;12(6):e0179001. doi: 10.1371/journal.pone.0179001. eCollection 2017.
PubMed 28591174
Hoel H, Hoiseth LO, Sandbaek G, Sundhagen JO, Mathiesen I, Hisdal J. The acute effects of different levels of intermittent negative pressure on peripheral circulation in patients with peripheral artery disease. Physiol Rep. 2019 Oct;7(20):e14241. doi: 10.14814/phy2.14241.
PubMed 31631579
Prompers L, Huijberts M, Apelqvist J, Jude E, Piaggesi A, Bakker K, Edmonds M, Holstein P, Jirkovska A, Mauricio D, Ragnarson Tennvall G, Reike H, Spraul M, Uccioli L, Urbancic V, Van Acker K, van Baal J, van Merode F, Schaper N. High prevalence of ischaemia, infection and serious comorbidity in patients with diabetic foot disease in Europe. Baseline results from the Eurodiale study. Diabetologia. 2007 Jan;50(1):18-25. doi: 10.1007/s00125-006-0491-1. Epub 2006 Nov 9.
PubMed 17093942
Petersen BJ, Linde-Zwirble WT, Tan TW, Rothenberg GM, Salgado SJ, Bloom JD, Armstrong DG. Higher rates of all-cause mortality and resource utilization during episodes-of-care for diabetic foot ulceration. Diabetes Res Clin Pract. 2022 Feb;184:109182. doi: 10.1016/j.diabres.2021.109182. Epub 2022 Jan 18.
PubMed 35063288
Armstrong DG, Boulton AJM, Bus SA. Diabetic Foot Ulcers and Their Recurrence. N Engl J Med. 2017 Jun 15;376(24):2367-2375. doi: 10.1056/NEJMra1615439. No abstract available.
PubMed 28614678
Zhang Y, Lazzarini PA, McPhail SM, van Netten JJ, Armstrong DG, Pacella RE. Global Disability Burdens of Diabetes-Related Lower-Extremity Complications in 1990 and 2016. Diabetes Care. 2020 May;43(5):964-974. doi: 10.2337/dc19-1614. Epub 2020 Mar 5.
PubMed 32139380

Interested in taking part?

Each site lists its own contact. Pick the site nearest to you.

Talk to your doctor first and take this page with you. Only the study team can confirm whether you can join.

Questions to ask the study team

What is the study trying to find out?
What would I need to do, and how often would I visit?
Could I receive a placebo instead of the treatment?
What are the possible risks and benefits for me?
Will it cost me anything? Are travel or time paid for?
Can I keep seeing my own doctor during the study?
What happens when the study ends?

See sites and contacts

Recruiting
PAW-Hydrogel for Chronic Wound Healing
Diabetic Foot Ulcer (DFU), Pressure Ulcer (PU)
Active, not recruiting
Wearable Insoles for Recurrent Diabetic Ulcer Prevention
Diabetes, Peripheral Neuropathy
Active, not recruiting
Evaluation of Personalized Nutritional Intervention on Wound Healing of Cutaneous Ulcers in Diabetics
Foot, Diabetic
Not yet recruiting
Efficacy Evaluation of Turmeric-Derived Nanoparticle Hydrogel for the Treatment of Diabetic Foot Ulcer Wounds
Diabete Mellitus
Not yet recruiting
Better Care Closer to Home: Enhancing Primary and Community Care
Diabetic Foot Disease, Recurrence

All Diabetic Foot Ulcer trials

Study at a glance

From the registry record, last updated by the sponsor on 10 Jul 2026. Recruitment status is as the sponsor reported it: confirm with the study team.

Official title: Intermittent Negative Pressure for Patients With Diabetic Foot Ulcers (INPRESS) Study
ClinicalTrials.gov ID: NCT07291817
Acronym / sponsor ID: INPRESS / 2024-4641
Conditions: Diabetic Foot Ulcer
Study type: Interventional
Recruitment status: Recruiting
Enrolment: 30 participants (estimated)
Lead sponsor: Lo Zhiwen JosephOther government
Collaborators: Otivio AS
Study start: 3 Nov 2025 (actual)
Primary completion: 2 Nov 2026 (estimated)
Study completion: 2 Nov 2026 (estimated)
First posted: 18 Dec 2025 (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.

Study design

Primary purpose: Other
Allocation: Not applicable
Intervention model: Single group
Masking: None (open label)
Number of arms: 1

Arm	Type	Receives
Treatment with FlowOx	Experimental	Device: FlowOx

Who may qualify

Ages: 21 to 99 years
Sex: All
Healthy volunteers: Not accepted
Age groups: Adult, Older adult

Key inclusion criteria (8 listed)

Provision of signed and dated informed consent form
Stated willingness to comply with all study procedures and availability for the duration of the study
Male or female, aged 21-99.
Diagnosed with diabetes mellitus.
Toe systolic pressure <90 mmHg on the leg to be treated (after revascularization)

Key exclusion criteria (3 listed)

Known allergic reactions to components of the INP device.
Treatment with another investigational intervention within the last 12 weeks prior to inclusion.
Pregnant women or cognitively impaired participants.

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
FlowOx12 weeks treatment with FlowOx for 1 hour twice daily for 12 weeks	Device	Treatment with FlowOx

Primary outcome

Change in toe arterial pressure
Time frame: 12 weeks
Toe systolic blood pressure is a commonly used tool to predict wound healing in patients with diabetic foot ulcers. * Tools used: Photoplethysmography (PPG) Probe/Sensor * Unit of measure: mmHg
Change in wound surface area
Time frame: 12 weeks
Change in wound surface area will be used as an indicator of treatment effect on wound healing. * Tool used: quantitative measurement of wound surface area * Unit of measure: cm2

3 secondary outcomes

Comparison of the primary outcomes (changes in toe arterial pressure and wound healing rate) and post diabetic limb salvage rate between a prospective cohort that is 1:1 propensity-scored matched against a retrospective cohort
Time frame: 12 weeks
Frequency of adverse events
Time frame: 12 weeks
Compliance (mean daily treatment time)
Time frame: 12 weeks

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 10 Jul 2026.
Background: PubMed 37847243Yagshyyev S, Hausmann P, Li Y, Kempf J, Zetzmann K, Dessi K, Moosmann O, Almasi-Sperling V, Meyer A, Gerken ALH, Lang W, Rother U. Intermittent negative pressure therapy in patients with no-option chronic limb-threatening ischemia. Vasa. 2023 Nov;52(6):402-408. doi: 10.1024/0301-1526/a001098. Epub 2023 Oct 17.
Background: PubMed 17856393Herrmann LG, Reid MR. THE CONSERVATIVE TREATMENT OF ARTERIOSCLEROTIC PERIPHERAL VASCULAR DISEASES: PASSIVE VASCULAR EXERCISES (PAVAEX THERAPY). Ann Surg. 1934 Oct;100(4):750-60. doi: 10.1097/00000658-193410000-00016. No abstract available.
BackgroundLandis E.M HLH. The clinical value of alternate suction and pressure in the treatment of advanced peripheral vascular disease. The American Journal of the Medical Sciences. 1935;189(3):20.
BackgroundSinkowitz S, Gottlieb I. Thrombo-angiitis obliterans the conservative treatment by Bier's hyperemia suction apparatus. JAMA.1917;LXVIII(13):961-963.
Background: PubMed 27798353Sundby OH, Hoiseth LO, Mathiesen I, Jorgensen JJ, Sundhagen JO, Hisdal J. The effects of intermittent negative pressure on the lower extremities' peripheral circulation and wound healing in four patients with lower limb ischemia and hard-to-heal leg ulcers: a case report. Physiol Rep. 2016 Oct;4(20):e12998. doi: 10.14814/phy2.12998.
Background: PubMed 29497177Sundby OH, Irgens I, Hoiseth LO, Mathiesen I, Lundgaard E, Haugland H, Weedon-Fekjaer H, Sundhagen JO, Sandbaek G, Hisdal J. Intermittent mild negative pressure applied to the lower limb in patients with spinal cord injury and chronic lower limb ulcers: a crossover pilot study. Spinal Cord. 2018 Apr;56(4):372-381. doi: 10.1038/s41393-018-0080-4. Epub 2018 Mar 1.
Background: PubMed 33899743Hoel H, Pettersen EM, Hoiseth LO, Mathiesen I, Seternes A, Hisdal J. A randomized controlled trial of treatment with intermittent negative pressure for intermittent claudication. J Vasc Surg. 2021 May;73(5):1750-1758.e1. doi: 10.1016/j.jvs.2020.10.024. Epub 2020 Oct 22.
Background: PubMed 28591174Sundby OH, Hoiseth LO, Mathiesen I, Weedon-Fekjaer H, Sundhagen JO, Hisdal J. The acute effects of lower limb intermittent negative pressure on foot macro- and microcirculation in patients with peripheral arterial disease. PLoS One. 2017 Jun 7;12(6):e0179001. doi: 10.1371/journal.pone.0179001. eCollection 2017.
Background: PubMed 31631579Hoel H, Hoiseth LO, Sandbaek G, Sundhagen JO, Mathiesen I, Hisdal J. The acute effects of different levels of intermittent negative pressure on peripheral circulation in patients with peripheral artery disease. Physiol Rep. 2019 Oct;7(20):e14241. doi: 10.14814/phy2.14241.
Background: PubMed 17093942Prompers L, Huijberts M, Apelqvist J, Jude E, Piaggesi A, Bakker K, Edmonds M, Holstein P, Jirkovska A, Mauricio D, Ragnarson Tennvall G, Reike H, Spraul M, Uccioli L, Urbancic V, Van Acker K, van Baal J, van Merode F, Schaper N. High prevalence of ischaemia, infection and serious comorbidity in patients with diabetic foot disease in Europe. Baseline results from the Eurodiale study. Diabetologia. 2007 Jan;50(1):18-25. doi: 10.1007/s00125-006-0491-1. Epub 2006 Nov 9.
Background: PubMed 35063288Petersen BJ, Linde-Zwirble WT, Tan TW, Rothenberg GM, Salgado SJ, Bloom JD, Armstrong DG. Higher rates of all-cause mortality and resource utilization during episodes-of-care for diabetic foot ulceration. Diabetes Res Clin Pract. 2022 Feb;184:109182. doi: 10.1016/j.diabres.2021.109182. Epub 2022 Jan 18.
Background: PubMed 28614678Armstrong DG, Boulton AJM, Bus SA. Diabetic Foot Ulcers and Their Recurrence. N Engl J Med. 2017 Jun 15;376(24):2367-2375. doi: 10.1056/NEJMra1615439. No abstract available.
Individual participant dataSharing planned: Yes. IPD will be made available on a data repository if required by the publishing journal.

Related trials for Diabetic Foot Ulcer

Recruiting
PAW-Hydrogel for Chronic Wound Healing
Diabetic Foot Ulcer (DFU), Pressure Ulcer (PU)
Active, not recruiting
Wearable Insoles for Recurrent Diabetic Ulcer Prevention
Diabetes, Peripheral Neuropathy
Active, not recruiting
Evaluation of Personalized Nutritional Intervention on Wound Healing of Cutaneous Ulcers in Diabetics
Foot, Diabetic
Not yet recruiting
Efficacy Evaluation of Turmeric-Derived Nanoparticle Hydrogel for the Treatment of Diabetic Foot Ulcer Wounds
Diabete Mellitus
Not yet recruiting
Better Care Closer to Home: Enhancing Primary and Community Care
Diabetic Foot Disease, Recurrence

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.

Woodlands Health

Singapore, Singapore

+65 6361 3262

wh.wounds@nhghealth.com.sg

Zhiwen Joseph Lo principal investigator

Woodlands Health

1 site in 1 country: see every site and its status.

Questions about this trial

What is this clinical trial studying?

A study testing FlowOx in people with Diabetic Foot Ulcer, run by Lo Zhiwen Joseph at 1 site in Singapore.

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 8 inclusion and 3 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 10 Jul 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 Singapore. 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?

Each site lists its own contact: choose the nearest one under Trial locations. AzTrials does not enrol participants or take referrals.

What does the primary outcome measure?

Change in toe arterial pressure (time frame: 12 weeks). 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?

On the ClinicalTrials.gov record for NCT07291817, which also lists 13 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 10 Jul 2026.