Written by the Nuvirox Research Team
Short answer: a 2025 randomized trial in hospitalized patients found NAD+ precursors safely and substantially raised blood NAD+ levels — but did not improve markers of acute kidney injury, inflammation, or disease severity. This is an honest null result worth taking seriously, not a hidden win.
Key Points
- NAD+ depletion is documented in acute kidney injury, giving researchers a real reason to test whether restoring it helps.
- A 2025 RCT in 42 hospitalized COVID-19 patients with acute kidney injury found NMN (as MIB-626) safely raised blood NAD+ substantially.
- Despite the safe NAD+ increase, the trial found no difference between groups in kidney injury markers, inflammation, or clinical severity.
Why kidney researchers got interested in NAD+
Acute kidney injury (AKI) involves a rapid decline in kidney function, often triggered by illness, reduced blood flow, or toxic exposure, and it's associated with measurable NAD+ depletion in kidney tissue as part of the injury process. Because NAD+ is essential for the mitochondrial energy production that kidney cells — among the most energy-hungry cells in the body — need to function and repair, restoring NAD+ levels became a logical therapeutic target for researchers studying ways to protect or support kidney function during acute illness.
What the 2025 trial actually did and found
Researchers ran a randomized, placebo-controlled trial testing oral MIB-626 (a crystalline form of NMN) at 1.0 g twice daily for 14 days in 42 adults hospitalized with both COVID-19 and acute kidney injury — a population chosen specifically because both conditions are associated with NAD+ depletion. The trial measured blood NAD+ and its metabolites, along with biomarkers of acute kidney injury, inflammation, and clinical disease severity [1].
Study snapshot: MIB-626 in hospitalized patients with COVID-19 and AKI
| Design | Randomized, placebo-controlled (3:2 ratio) |
| Population | 42 adults hospitalized with COVID-19 and acute kidney injury |
| Dose / duration | 1.0 g MIB-626 twice daily, 14 days |
| Key finding | NAD+ rose substantially and safely; AKI, inflammation, and severity markers did NOT differ from placebo |
The result was a clean, honest split: MIB-626 treatment significantly and safely raised blood NAD+ levels, gradually rising to a peak between days 5 and 14 — confirming the drug did what it was designed to do at the biochemical level. But markers of acute kidney injury, inflammation, and disease severity did not differ between the treatment and placebo groups, with researchers noting this was likely due to the slow rise in NAD+ levels relative to how quickly AKI often needs to be addressed.
Why this null result is actually useful information
This trial deserves real credit for testing a clean, specific hypothesis in a population where the mechanism should matter most, and reporting the null result honestly rather than only publicizing the safety and NAD+-raising success. It tells us something concrete: simply raising blood NAD+ levels, even substantially, doesn't automatically translate into a clinical kidney benefit within a two-week hospitalized-illness timeframe. That's valuable negative information, and exactly the kind of study the broader NAD+ supplement space needs more of.
What NAD+ won't do
Nothing in current research supports NAD+ precursors as a treatment or protective strategy for acute kidney injury, chronic kidney disease, or any diagnosed kidney condition. If you have any kidney concern — elevated creatinine, reduced eGFR, a CKD diagnosis, or a kidney-related hospitalization — that requires direct medical management, and this research (a null result in exactly this context) is a reason for caution, not encouragement, about relying on supplements in that situation. Additionally, because compromised kidney function can affect how supplements and their metabolites are cleared from the body, anyone with a diagnosed kidney condition should specifically check with their doctor before adding any new supplement, including NAD+ precursors.
Frequently asked questions
Do NAD+ supplements help kidney function?
The most directly relevant trial — in hospitalized patients with acute kidney injury — found NAD+ precursors safely raised NAD+ levels but did not improve kidney injury markers. This is a genuine null result for kidney-specific benefit.
Is it safe to take NAD+ precursors if I have kidney disease?
The trial found MIB-626 was safe to administer even in hospitalized patients with acute kidney injury, which is reassuring from a safety standpoint. Still, anyone with diagnosed kidney disease should check with their doctor before adding any supplement, since kidney function affects how substances are cleared from the body.
Why did NAD+ levels rise but kidney markers not improve?
Researchers suggested the rise in NAD+ was too gradual relative to how quickly acute kidney injury needs to be addressed — a 14-day, slowly-building increase may simply not match the timeline of acute injury and recovery.
Does this mean NAD+ precursors are useless for everything?
No — this was one specific trial in one specific acute, hospitalized context. It doesn't tell us about other NAD+ applications (like cardiovascular or metabolic outcomes) that have shown different results in their own trials.
Liver and kidney research on NAD+ precursors follow a similar arc of real trials with mixed results — see our companion article on NAD+ and liver health for a case where the human evidence was more encouraging, and our broader look at NAD+ and heart health and NAD+ supplement side effects for the general human safety record.
Would a longer trial duration have shown a kidney benefit?
It's possible — the researchers specifically noted the slow rise in NAD+ levels relative to how quickly acute kidney injury needs to be addressed as a likely reason for the null result, which leaves open whether a longer or earlier intervention window might perform differently. That hasn't been tested yet.
It’s worth understanding why researchers chose hospitalized COVID-19 patients with acute kidney injury as the test population rather than, say, people with chronic kidney disease. COVID-19 was specifically associated with NAD+ depletion tied to the innate immune response mounted against the virus, giving researchers a defined, acute window in which to test whether restoring NAD+ could blunt kidney injury as it was actively happening — a cleaner experimental setup than trying to study NAD+ effects in the slower, more variable progression of chronic kidney disease. That the trial still found no benefit on kidney-specific outcomes, despite this relatively favorable test design, is part of why the null result carries real weight rather than being dismissed as a poorly designed study.
From Nuvirox
Why we formulated NAD+ Restore
If what you're dealing with sounds like it belongs in a doctor's office rather than a supplement aisle, please start there — a clinician can rule out the specific causes discussed above. For general cellular energy support, each serving of NAD+ Restore provides 500 mg of nicotinamide riboside chloride (NR), one of the two most-researched NAD+ precursors, within the dose range used in published human trials, alongside 150 mg trans-resveratrol and 50 mg quercetin (polyphenols studied alongside NAD+ pathways for cellular health support) and 10 mg of galactomannans from fenugreek to support absorption.
We back it with a 60-day money-back guarantee — long enough to actually evaluate it the way the research says you should.
Learn more about NAD+ Restore →The bottom line
This is a rare example of a well-designed NAD+ trial reporting a clear null result on its primary clinical question, and that's worth respecting rather than glossing over. NAD+ precursors did exactly what they were supposed to do biochemically — raise blood NAD+ safely — but that didn't translate into improved kidney outcomes in this acute, hospitalized setting. If you're managing any kidney condition, this evidence argues for caution and a direct conversation with your doctor, not supplementation.
References
- Valderrabano RJ, Pencina KM, et al. Oral MIB-626 (β Nicotinamide Mononucleotide) Safely Raises Blood NAD Levels in Hospitalized Patients With COVID-19 and Acute Kidney Injury: A Randomized Controlled Trial. FASEB BioAdv. 2025;7(8):e70011. doi:10.1096/fba.2025-00014. PMID: 40746868.
- Pencina KM, Valderrabano R, Wipper B, et al. Nicotinamide Adenine Dinucleotide Augmentation in Overweight or Obese Middle-Aged and Older Adults: A Physiologic Study. J Clin Endocrinol Metab. 2023;108(8):1968-1980. doi:10.1210/clinem/dgad027.
*These statements have not been evaluated by the Food and Drug Administration. This product is not intended to diagnose, treat, cure, or prevent any disease. This article is for informational purposes only and is not a substitute for professional medical advice.