Oral MIB‐626 (β Nicotinamide Mononucleotide) Safely Raises Blood Nicotinamide Adenine Dinucleotide Levels in Hospitalized Patients With COVID‐19 and Acute Kidney Injury: A Randomized Controlled Trial

ABSTRACT

Nicotinamide adenine dinucleotide (NAD⁺) plays an important role in the innate immune response and is depleted during SARS‐CoV‐2 infection due to increased turnover. It is unknown whether treatment with NAD⁺ precursors can safely raise NAD⁺ levels in patients with COVID‐19. To determine whether MIB‐626 (β‐nicotinamide mononucleotide), an NAD⁺ precursor, can safely increase blood NAD⁺ levels and attenuate acute kidney injury (AKI) and inflammation in hospitalized patients with COVID‐19, 42 adults, ≥ 18 years, hospitalized with COVID‐19 and AKI, were randomized in a 3:2 ratio to MIB‐626 1.0‐g or placebo tablets twice daily for 14 days. Circulating NAD⁺ and its metabolites, markers of AKI, inflammation, and disease severity, were assessed. MIB‐626 treatment significantly but gradually raised blood NAD⁺ levels to a peak between 5 to 14 days (16.0 ± 6.9, 25.5 ± 12.6, and 42.6 ± 25.6 μg/mL at baseline, days 5 and 14) and raised plasma concentrations of NAD⁺ metabolites 1‐methylnicotinamide, N‐methyl, 2‐pyridone, 4‐carboxamide rapidly to a peak by day 3. Changes in serum creatinine, cystatin‐C, and serum markers of AKI did not differ significantly between groups. Serum CRP, IL‐6, and TNFα and indices of disease severity also did not differ between groups. MIB‐626 treatment of patients with COVID‐19 and AKI safely and substantially raised blood NAD⁺ and plasma concentrations of NAD⁺ metabolites. Markers of AKI, inflammation, and disease severity did not differ between groups, likely due to the slow rise in NAD⁺ levels. Future studies should assess whether a rapid increase in NAD⁺ by parenteral administration can attenuate disease severity and AKI.

Trial Registration: ClinicalTrials.gov Identifier: NCT05038488

This randomized, placebo‐controlled trial assessed the effects of NAD augmentation by administration of oral β Nicotinamide Mononucleotide (β NMN) 1.0 g twice daily or placebo for 14 days in adult patients hospitalized with COVID‐19 and acute kidney injury on blood NAD, plasma levels of NAD metabolites, biomarkers of acute kidney injury, inflammation, and clinical indices of disease severity. β NMN treatment of patients with COVID‐19 and AKI safely and substantially raised blood NAD⁺ and plasma concentrations of NAD⁺ metabolites. Markers of AKI, inflammation, and disease severity did not differ between groups, likely due to a slow rise in NAD⁺ levels.

A majority of people infected with SARS‐CoV‐2 suffer from a mild respiratory illness or remain asymptomatic; however, a subset of patients develops a more severe illness that can progress to acute respiratory distress syndrome, multi‐organ failure, including acute kidney injury (AKI), and death [1, 2, 3, 4]. A dysregulated, heightened inflammatory response in patients with COVID‐19 contributes to disease severity and the development of acute respiratory distress syndrome, AKI, and multi‐organ failure [5, 6, 7].

The recognition of the important role of an aggressive inflammatory response in the pathophysiology of multiorgan failure, including AKI, in COVID‐19 has motivated the development of therapeutic strategies to attenuate the inflammatory response, improve disease outcomes, and prevent or attenuate multi‐organ damage [8, 9]. Several therapeutic interventions to dampen the inflammatory response have been investigated; these include glucocorticoids [10], selective IL‐6 antagonists such as tocilizumab [11, 12], JAK inhibitors such as baricitinib [13], and NAD⁺ augmentation [14]; among these, dexamethasone, tocilizumab, and baricitinib are approved for subsets of patients with COVID‐19. NAD⁺ plays an important role in the body's innate immune response to viral infections, including SARS‐CoV‐2 infection, by regulating the formation of the nucleotide‐binding domain, leucine‐rich–containing family, pyrin domain–containing‐3 (NLRP3) inflammasome, stress granules, and transcription of NFκB, and is therefore an attractive modifiable target [14]. NAD⁺ serves as a cofactor for enzymes that regulate innate immune response such as sirtuins, PARPs, CD38, and SARM1. NAD⁺ is depleted during SARS‐CoV‐2 infection due to its increased consumption and degradation [15, 16]. Administration of NAD⁺ precursors, nicotinamide mononucleotide (NMN), nicotinamide riboside (NR), and nicotinamide (NAM), increases NAD⁺ levels in blood and other tissues [17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27], downregulates the NLRP3 inflammasome, and attenuates the inflammatory response in experimental models of inflammation and acute viral infection [15, 28, 29, 30]. In a pilot randomized clinical trial, NAM was reported to attenuate creatinine elevation in patients undergoing cardiac surgery; the trial did not report the levels of NAD⁺ or its metabolites [31]. An open‐label study of NAM also reported an association between NAM receipt and a lower risk of dialysis or death among hospitalized patients with COVID‐19‐related AKI compared to contemporaneous and historical controls, but this trial also did not report the levels of NAD⁺ or its metabolites [32]. Thus, no randomized controlled trial has evaluated whether oral NAD⁺ precursors can raise blood NAD⁺ levels, attenuate the inflammatory response, and AKI in patients hospitalized with COVID‐19. This issue has assumed increased importance because our recent observational study revealed that NAD⁺ turnover is markedly increased in patients hospitalized with COVID‐19 [16], raising the question of whether administration of NAD⁺ precursors, such as NMN or NR, can adequately raise NAD⁺ levels in patients with COVID‐19 as they do in healthy adults [18, 19].

This proof‐of‐concept, early‐phase randomized, placebo‐controlled trial was designed to determine whether treatment with MIB‐626, a microcrystalline polymorph formulation of βNMN, in adults with COVID‐19 AKI, is safe and efficacious in raising blood NAD⁺ levels. An additional aim was to assess whether augmenting NAD⁺ by βNMN administration can prevent worsening of kidney function, assessed by changes in serum creatinine concentration and serum and urinary markers of AKI. The trial also evaluated the effects of MIB‐626 on inflammatory markers and clinical indices of disease severity. The safety endpoints included adverse events, clinical laboratory evaluations, and vital signs.

1. Methods

This placebo‐controlled, randomized, parallel group, double‐blind trial was conducted at 3 trial sites: Brigham and Women's Hospital in Boston, MA; University of Texas Medical Branch, Galveston, TX; and Tulane University Medical Center, New Orleans, LA. The study protocol was approved by the trial's single institutional review board (sIRB) at the Mass General Brigham Human Research Protection Program and the institutional review boards of the participating trial sites ceded to the sIRB. An independent Data and Safety Monitoring Board (DSMB) reviewed the safety data and study progress every 6 weeks to 3 months. The participants provided consent and authorization for the use and disclosure of personal health information in accordance with the Health Insurance Portability and Accountability Act. The trial was registered at ClinicalTrials.gov.

1.1. Eligibility Criteria

The participants were community‐dwelling adults, 18 years or older, hospitalized with SARS‐CoV‐2 infection, confirmed by an approved diagnostic test, and AKI. The latter was defined as an absolute increase in serum creatinine ≥ 0.3 mg/dL above baseline within a 48‐h period, or a relative increase in serum creatinine ≥ 50% above the average of the two most recent serum creatinine values within the 12 months prior to the index hospitalization. Exclusion criteria included: (1) admission to an intensive care unit or receipt of invasive mechanical ventilation prior to randomization; (2) baseline estimated glomerular filtration rate < 30 mL/min/1.73m²; (3) kidney transplantation or receipt of hemodialysis or peritoneal dialysis; (4) lupus nephritis, polycystic kidney disease, or any glomerular disease other than diabetic kidney disease; (5) AST or ALT > 3 times the upper limit of normal; or (6) contraindication for MIB‐626 receipt or its inert ingredient. Patients who were receiving remdesivir or dexamethasone as a part of their clinical care or were in trials of remdesivir or other antiviral drugs were allowed if they met other eligibility criteria. Patients enrolled in intervention trials of anti‐inflammatory or immunomodulatory agents were excluded. The use of acetaminophen and nonsteroidal anti‐inflammatory drugs, such as ibuprofen, for fever or headache was permitted. Women who were pregnant or planning to become pregnant over the next 6 months, or breastfeeding, were excluded.

1.2. Participant Randomization by Minimization

Eligible participants were assigned to receive either MIB‐626 or placebo in a 3:2 ratio using concealed randomization by minimization based on prognostic factors: age group (18–65, > 65), sex, receipt of antiviral drugs, such as remdesivir, or receipt of dexamethasone.

1.3. Intervention

MIB‐626, a microcrystalline tablet formulation of βNMN, was supplied at a dose strength of 500 mg per tablet. Participants received either 1000 mg of MIB‐626 (two 500‐mg tablets) twice daily or two matching placebo tablets twice daily for 14 consecutive days. Participants who were discharged from the hospital prior to 14 days completed the remainder of the treatment at home. The selection of the 1.0 g twice daily dose of NMN was informed by our previous pharmacokinetic and pharmacodynamic studies that revealed that this dose regimen was safe and efficacious in raising blood NAD⁺ levels by more than 250% above baseline over a 14‐day period in healthy middle‐aged and older adults [19]. These pharmacokinetic studies also found that doses of less than 1.0 g daily only marginally raised blood NAD levels. Furthermore, in a cross‐sectional study of patients hospitalized with the SARS‐CoV‐2 infection, we found that NAD⁺ turnover was substantially increased with a marked upregulation of NAD degrading enzymes [16]; therefore, we surmised that a higher dose of NMN might be needed in people with COVID‐19 to raise the NAD⁺ levels compared to healthy adults [19].

1.4. Blinding

The participants, study staff, and hospital personnel providing clinical care to the study participants were blinded. The treatment assignment was known only to the unblinded biostatistician and the pharmacy staff dispensing the study medication.

1.5. Study Outcomes

Blood NAD⁺ levels and plasma levels of its major metabolites—nicotinamide, 1‐methylnicotinamide (MeNAM), and N‐methyl, 2‐pyridone, 4‐carboxamide (2PY) – were measured at baseline and on days 3, 5, 14, and 42. The primary efficacy endpoint was the change in serum creatinine from baseline. Secondary endpoints included change from baseline in additional measures of AKI: serum cystatin C, KIM‐1, and NGAL. Severity of COVID‐19 was assessed using the WHO ordinal scale and modified Sequential Organ Failure Assessment (mSOFA) scale. Serum creatinine, cystatin C, and other markers of AKI (KIM‐1 and NGAL) were measured at baseline and on days 2, 3, 5, 7, 9, 14, 42, and 90, if the patients were in the hospital on these days. Blood samples for biomarkers of inflammation were collected at baseline and on days 2, 3, 5, 7, 9, 14, and 42. Clinical indices of disease severity were ascertained from the electronic medical record during the hospital stay or by direct measurements during scheduled visits to the clinical research center. Patients who were discharged prior to day 14 were asked to return to the research unit on day 14 for end‐of‐study assessments.

To ensure preanalytical stability of the analytes, whole blood, immediately after sample draw, was added to a tube containing 4% trichloroacetic acid (TCA) in a 6:1 ratio of TCA to blood. The measurements of NMN and NAD⁺ were performed using liquid chromatography coupled with mass spectrometry using positive ion electrospray, as described previously [18, 19]. The LC was performed on Waters ACQUITY UPLC and Thermo, Hypercarb, 100 × 2.1 mm column with a mobile phase A of water: ammonium formate: ammonium hydroxide at 1000:7.5:0.5 ratio and a mobile Phase B of acetonitrile: ammonium hydroxide at 1000:0.5 ratio, run at a flow rate of 0.5 mL/min. We utilized Sciex API5000 for NMN and Sciex API4000 using positive ion electrospray for NAD⁺. The linear quantitation range for NMN was 0.2 to 20.0 μg/mL and for NAD 5.0 to 500.0 μg/mL. Interassay coefficients of variation for the NMN assay were 6.0%, 3.1%, and 3.0% in low (0.36 μg/mL), medium (7.4 μg/mL) and high (14 μg/mL) quality control pools, respectively, and for the NAD⁺ assay 8.7%, 6.7%, and 4.6% in quality control pools with concentrations of 19.2, 197, and 392 μg/mL, respectively.

NAD⁺ metabolites—NAM, MeNAM, and 2‐PY in plasma—were measured using a previously described LC–MS method [18, 19] that used an Agilent Zorebax SA‐AQ, 100 × 3.5 mm, 3.5 mm column on a Waters ACQUITY UPLC system and a Sciex API6500 mass spectrometer in positive ion electrospray mode for detection and quantitation.

Serum interleukin 6 (IL‐6) was measured by a two‐site chemiluminescent immunoassay with interassay CVs 3.1%–12.0% (Access Systems, Beckman Coulter Inc. Fullerton, CA). Human TNF‐α was measured using an enzyme‐linked immunosorbent assay (ELISA) with interassay CVs 7.3%–10.6% (R & D Systems Inc., Minneapolis, MN). C‐Reactive Protein (CRP) was measured by a validated ELISA; interassay CVs were 6.0%–7.0% (R & D Systems Inc., Minneapolis, MN).

1.6. Statistical Analyses

The analyses were performed using SAS 9.3 software (Cary, NC) or R software version 3.2.4 (http://www.r‐project.org). Mixed‐model repeated measures regression analyses were employed to assess average change from baseline in serum creatinine levels over the 14‐day intervention period. This analysis was performed on the intent‐to‐treat population that included all available data at planned time points. For this model, the dependent variable was expressed as the change from the baseline visit. Independent variables in this model included baseline value, study site, treatment arm (active or placebo), visit, and treatment‐by‐visit interaction. An unstructured covariance matrix was used for the model. If the unstructured covariance structure matrix resulted in a lack of convergence, the compound symmetry covariance structure was assumed. The Markov Chain Monte Carlo method was employed to assess the robustness of the results due to missing records. Sensitivity analyses were performed after excluding one participant who did not meet eligibility criteria (baseline creatinine 6.0 mg/dL) and was erroneously randomized. Additional sensitivity analysis used multiple imputation to account for missing data.

Between‐group differences in the secondary endpoints were analyzed in a manner similar to the primary endpoint. No adjustment for multiplicity was made in this proof‐of‐principle exploratory study. All P values are considered nominal.

Adverse events are presented according to SOC and MedDRA categories both as absolute numbers of events and the number of participants experiencing one or more events. Effects of the intervention on changes in continuous safety metrics were analyzed using mixed‐model repeated measures regression.

2. Results

2.1. Baseline Characteristics

Among 79 hospitalized patients who were deemed eligible, 42 (including 23 men and 19 women) consented to participate and were randomized; 25 were randomized to MIB‐626 and 17 to the placebo group (CONSORT Diagram, Figure S1). One person did not meet all inclusion criteria but was mistakenly randomized; the results are presented for all randomized participants (intent‐to‐treat population) as well as for the sensitivity analysis in which this participant with a baseline creatinine of 6 mg/dL was excluded.

The baseline characteristics of study participants (Table 1) were in general similar between the two groups. The mean ± SD age of the participants was 68.4 ± 13.4 years. The mean body weight was 84.0 ± 19.5 kg, and body mass index was 29.9 ± 6.7 kg/m². The patient population had an overall high burden of chronic diseases; 33% had diabetes mellitus, 57% had hypertension, 10% had cancer, and 29% had heart failure. The baseline chemistries, blood counts, oxygen saturation, acute kidney injury markers, liver enzymes, and inflammatory metrics did not differ meaningfully between groups (Table 1).

TABLE 1.

Baseline characteristics of the study participants (ITT population).

	Placebo (N = 17)	1000 mg twice daily (N = 25)	All participants (N = 42)
Sex
Female	6.0 (35.3%)	13.0 (52.0%)	19.0 (45.2%)
Male	11.0 (64.7%)	12.0 (48.0%)	23.0 (54.8%)
Age (years)	65.0 ± 12.2	70.7 ± 14.0	68.4 ± 13.4
Body Weight (kg)	85.3 ± 22.4	83.2 ± 17.7	84.0 ± 19.5
BMI (kg/m2)	29.7 ± 6.3	30.0 ± 7.1	29.9 ± 6.7
Diabetes mellitus, n (%)	4.0 (23.5%)	10.0 (40.0%)	14.0 (33.3%)
Hypertension, n (%)	11.0 (64.7%)	13.0 (52.0%)	24.0 (57.1%)
Coronary Artery Disease, n (%)	2.0 (11.8%)	4.0 (16.0%)	6.0 (14.3%)
Congestive Heart Failure, n (%)	5.0 (29.4%)	7.0 (28.0%)	12.0 (28.6%)
Hyperlipidemia, n (%)	9.0 (52.9%)	12.0 (48.0%)	21.0 (50.0%)
Hypercholesterolemia, n (%)	1.0 (5.9%)	2.0 (8.0%)	3.0 (7.1%)
Cancer, n (%)	0.0 (0.0%)	4.0 (16.0%)	4.0 (9.5%)
Oxygen delivery methods
Low‐Flow Nasal Cannula	3.0 (17.6%)	6.0 (24.0%)	9.0 (21.4%)
Room Air	14.0 (82.4%)	18.0 (72.0%)	32.0 (76.2%)
CPAP/BiPAP	0.0 (0.0%)	1.0 (4.0%)	1.0 (2.4%)
8 point ordinal scale
3 = Hospitalized, not requiring supplemental oxygen	14.0 (82.4%)	20.0 (80.0%)	34.0 (81.0%)
4 = Hospitalized, requiring supplemental oxygen by mask or nasal prongs	3.0 (17.6%)	5.0 (20.0%)	8.0 (19.0%)
Oxygen saturation (%)	96.8 ± 2.0	97.4 ± 1.8	97.1 ± 1.9
8 Point Ordinal Scale Score	3.2 ± 0.4	3.2 ± 0.4	3.2 ± 0.4
Systolic Blood Pressure (mm Hg)	125.1 ± 21.0	119.0 ± 18.3	121.5 ± 19.4
Diastolic Blood Pressure (mm Hg)	67.5 ± 9.1	60.9 ± 7.3	63.7 ± 8.7
WBC (Thousand/uL)	8.1 ± 3.7	8.8 ± 4.5	8.5 ± 4.1
Hemoglobin (g/dL)	11.3 ± 3.1	10.5 ± 2.6	10.8 ± 2.8
Hematocrit (%)	34.8 ± 9.8	31.9 ± 7.8	33.1 ± 8.7
Platelet (Thousand/uL)	232.6 ± 135.0	219.8 ± 137.4	225.0 ± 134.9
Absolute Neutrophils (cells/uL)	5657.7 ± 2699.7	6629.7 ± 3491.7	6230.9 ± 3189.1
Absolute Lymphocytes (cells/uL)	1380.3 ± 1050.8	1546.8 ± 1973.9	1478.5 ± 1642.7
Glucose (mg/dL)	124.8 ± 49.8	138.0 ± 66.3	132.7 ± 59.9
Creatinine (mg/dL)	1.9 ± 0.8	2.1 ± 1.3	2.0 ± 1.1
Cystatin C (mg/L)	2.8 ± 1.6	3.5 ± 3.0	3.2 ± 2.6
BUN (mg/dL)	47.3 ± 25.4	46.8 ± 21.7	47.0 ± 23.0
Serum KIM‐1 (pg/mL)	462.7 ± 515.5	429.4 ± 325.7	442.7 ± 406.3
Serum NGAL (pg/mL)	2294.6 ± 1390.9	2660.5 ± 1695.8	2497.9 ± 1557.0
Sodium (mmol/L)	137.4 ± 4.2	137.1 ± 3.6	137.2 ± 3.8
Total Protein (g/dL)	6.6 ± 0.8	6.2 ± 1.3	6.4 ± 1.1
Albumin (g/dL)	3.5 ± 0.5	3.3 ± 0.6	3.4 ± 0.6
AST (U/L)	42.9 ± 34.0	33.4 ± 27.2	37.2 ± 30.1
ALT (U/L)	46.6 ± 58.6	28.0 ± 31.0	35.5 ± 44.6
Troponin (ng/L)	16.4 ± 16.4	45.6 ± 89.0	34.8 ± 72.0
mSOFA Score (0–19)	4.4 ± 2.5	4.8 ± 2.1	4.7 ± 2.2
CRP (mg/L)	44.0 ± 59.5	64.4 ± 71.3	56.3 ± 66.8
IL‐6 (pg/mL)	20.5 ± 17.9	49.9 ± 58.0	38.1 ± 48.2
TNF‐alpha (pg/mL)	2.4 ± 0.8	2.5 ± 1.5	2.5 ± 1.3

Note: Result shown as mean ± SD for continuous and number (%) for categorical data.

Abbreviations: ALT, alanine aminotransferase; AST, asparate aminotransferase; BMI, Body Mass Index; CRP, C‐reactive protein; IL‐6, interleukin‐6; mSOFA, modified sequential organ failure assessment scale; TNF, tumor necrosis factor; WBC, White Blood Cell.

2.2. Blood Levels of NAD ⁺

MIB‐626 treatment resulted in a significant increase in blood NAD⁺ levels from baseline to Day 14 compared to placebo (Figure 1). The NAD⁺ levels were substantially higher on Day 14 than at baseline in the participants treated with MIB‐626. The blood NAD⁺ levels rose gradually and reached steady‐state peak levels between days 5 to 14 in MIB‐626‐treated participants. Blood NAD⁺ levels did not change during the 14‐day treatment period in the placebo group. Blood NAD⁺ levels on day 42 did not differ from baseline levels in either group.

FIGURE 1.

(A) Absolute Blood NAD⁺ Concentrations (left panel) and (B) Change from Baseline in Blood NAD⁺ Concentrations (right panel) in MIB‐626‐treated and Placebo‐Treated Patients. The Data are mean ± 95% confidence intervals. The study participants were treated with either NMN 1.0 g twice daily or an equal number of placebo tablets twice daily for 14 consecutive days. One patient, who did not meet the eligibility criteria, was erroneously enrolled and was excluded from the analysis. Sensitivity analysis with the inclusion of this participant yielded similar results.

2.3. Plasma Concentrations of NMN and NAD ⁺ Metabolites

The plasma concentrations of NMN did not change significantly in either group. However, the plasma concentrations of the NAD⁺ metabolites, N‐methyl‐2‐pyridone‐5‐carboxamide (2‐PY) and 1‐methyl nicotinamide (MeNAM), were significantly higher than baselines at all timepoints during the 14‐day intervention in the MIB‐626 group (Figure 2); the changes from baseline in the plasma concentrations of each metabolite were significantly greater in the MIB‐626 group than in the placebo group. In contrast to the blood NAD⁺ levels, which rose gradually to a peak level between days 5 and 14, the circulating plasma concentrations of NAD⁺ metabolites, MeNAM and 2‐PY, had reached a peak on day 3 (approximately 48 h after the first dose) which was the first time point when these metabolites were measured after randomization. Plasma concentrations of nicotinamide did not change significantly in the MIB‐626 group. The circulating concentrations of NAD⁺ metabolites did not change significantly from baseline in the placebo group.

FIGURE 2.

Plasma Concentrations of NAD⁺ Metabolites in MIB‐626‐Treated and Placebo‐treated Patients. (A) Plasma NMN; (B) Plasma 1‐MeNAM; (C) Plasma NAM; (D) Plasma 2‐PY. The Data are mean ± 95% confidence intervals. The study participants were treated with either NMN 1.0 g twice daily or an equal number of placebo tablets twice daily for 14 consecutive days. One patient, who did not meet the eligibility criteria, was erroneously enrolled and was excluded from the analysis. Sensitivity analysis with the inclusion of this participant yielded similar results.

2.4. Serum Creatinine, Cystatin C, and Blood Urea Nitrogen

The changes in serum creatinine levels from baseline over the 14‐day intervention period did not differ significantly between groups (Figure 3). Similarly, changes from baseline in serum cystatin C and BUN did not differ between groups (Figure 3). Sensitivity analysis of the primary outcome using multiple imputation to account for missing data showed similar results.

FIGURE 3.

Markers of Kidney Function: (A) Serum Creatinine (upper panel), (B) Cystatin S (middle panel), and (C) Blood Urea Nitrogen (BUN, lower panel). The Data are mean ± 95% confidence intervals. The study participants were treated with either NMN 1.0 g twice daily or an equal number of placebo tablets twice daily for 14 consecutive days. One patient, who did not meet the eligibility criteria, was erroneously enrolled and was excluded from the analysis. Sensitivity analysis with the inclusion of this participant yielded similar results.

2.5. Circulating Markers or Acute Kidney Injury

Serum concentrations of NGAL and KIM‐1, markers of acute kidney injury, showed substantial variability over time in both groups (Figure 4). The change from baseline in circulating levels of NGAL and KIM‐1 did not differ significantly between the MIB‐626 and placebo groups.

FIGURE 4.

Markers of Acute Kidney Injury: (A) Serum NGAL (left panel), (B) Serum KIM‐1 (right panel). The Data are mean ± 95% confidence intervals. The study participants were treated with either NMN 1.0 g twice daily or an equal number of placebo tablets twice daily for 14 consecutive days. One patient, who did not meet the eligibility criteria, was erroneously enrolled and was excluded from the analysis. Sensitivity analysis with the inclusion of this participant yielded similar results.

2.6. Inflammation Markers

The inflammation markers hsCRP, IL‐6, and TNF‐alpha varied substantially among subjects in both groups. However, the changes from baseline in hsCRP, IL‐6, and TNF‐alpha levels did not differ between the MIB‐626 and placebo groups (Figure 5).

FIGURE 5.

Circulating Concentrations of Inflammation Markers, C Reactive Protein (CRP, upper panel), Tumor Necrosis Factor—Alpha (TNF‐alpha, middle panel), and Interleukin‐6 (IL‐6, lower panel The Data are mean ± 95% confidence intervals. The study participants were treated with either NMN 1.0 g twice daily or an equal number of placebo tablets twice daily for 14 consecutive days. One patient, who did not meet the eligibility criteria, was erroneously enrolled and was excluded from the analysis. Sensitivity analysis with the inclusion of this participant yielded similar results. CRP, C‐reactive protein; IL‐6, interleukin–6; TNF alpha, tumor necrosis factor alpha.

2.7. Clinical Indices of Disease Severity

There were no significant between‐group differences in the change in WHO Ordinal Scale score over time, or change in mSOFA scale score over time (Figure S3).

2.8. Safety Events

There were 7 serious adverse events (SAEs) reported by 6 individuals in the placebo group and 7 SAEs reported by 7 people in the MIB‐626 group. A total of 58 adverse events (AEs) were reported by 19 participants; among these, 45 occurred in 11 participants assigned to the MIB‐626 group, and 13 occurred in 8 participants in the placebo group. The frequency of adverse events by System Organ Class is presented in Table S1. The majority of AEs were classified as mild or moderate and were not related to study medication. One participant in the placebo group reported a cardiovascular AE classified as moderate (syncope episode) and 5 participants in the MIB‐626 arm reported cardiovascular events classified as mild or moderate (elevated troponin, bradycardia, tachycardia, hypertension, hypotension, and lightheadedness).

There was no clinically meaningful difference over the 14‐day intervention in changes from baseline in liver enzymes (ALT, AST, ALP), blood counts, fasting glucose, and other blood chemistries between the MIB‐626 and placebo groups (Table S3).

3. Discussion

This is the first randomized, placebo‐controlled trial of NAD⁺ augmentation in patients hospitalized with moderately severe SARS‐CoV‐2 infection to show that MIB‐626 was safe, well tolerated, and efficacious in raising blood NAD⁺ levels in patients with COVID‐19. The present study also shows that blood NAD⁺ levels are only modestly lower in patients with COVID‐19 compared to healthy adults without COVID‐19 but that the circulating concentrations of NAD⁺ metabolites such as MeNAM, NAM, and 2‐PY are markedly increased in patients with COVID‐19 compared with healthy adults, suggesting increased turnover of NAD⁺ due to marked upregulation of enzymes involved in NAD consumption as well as synthesis, as suggested by our previous observational study of patients with COVID‐19 [16]. In spite of the increased NAD⁺ turnover during acute COVID‐19, the MIB‐626 regimen used in this study (1.0 g twice daily) significantly raised NAD⁺ levels, although the increment above baseline was lower than that observed in our previous studies in healthy adults with a similar dose regimen [18, 19].

Consistent with our previous phase 1 studies [18, 19], blood NAD⁺ levels rose gradually in MIB‐626‐treated patients and reached the peak steady state levels between days 5 and 14, even though the plasma levels of its metabolites, MeNAM and 2‐PY, reached peak levels by day 3, which was the earliest sampling time point after randomization. The reasons for the slow ramp up of blood NAD⁺ levels in spite of a more rapid increase in circulating levels of its metabolites after oral NMN administration are not clear. It is possible that a longer time period is required to reach peak steady state levels due to the substantially increased NAD⁺ turnover in patients with COVID‐19. The mechanisms by which oral NAD⁺ precursors, NMN and NR, increase blood and tissue NAD⁺ levels need further investigation by metabolic flux studies using stable isotope‐labeled NAD⁺ precursors.

This relatively small trial did not reveal significant differences in serum creatinine or cystatin C or other serum markers of acute kidney injury, or in other clinical indices of disease severity. Due to the small sample size and substantial variability in the study's clinical endpoints in acutely ill patients with multiple comorbidities, the study likely did not have sufficient statistical power to detect meaningful differences in these endpoints. It took more than 5 days to achieve peak NAD⁺ levels by which time, many patients had been discharged and this may have obscured the drug's efficacy. Alternate parenteral routes of administration, such as intravenous, may be needed to raise NAD⁺ levels more rapidly than the oral route of administration during the first few days of the symptomatic phase of the infection. Intravenous NMN and NR have been shown to rapidly raise blood and tissue NAD⁺ [21, 33]. Another trial in ambulatory patients with COVID‐19 reported shorter recovery times with a combined cocktail that included L‐serine, N‐acetyl cysteine, NR, and L‐carnitine tartrate; the trial did not report serum creatinine, cystatin C, or NAD⁺ levels [34].

The efficacy data should be interpreted in the context of its strengths and limitations. Because the patients were hospitalized at the time of their randomization and the drug was administered by the hospital staff, adherence was high during the hospital stay but may have been variable after hospital discharge. The sample size was small. The trial was conducted in the midst of the COVID‐19 pandemic, which limited the amount of blood that could be drawn; thus mechanistic studies were not feasible. The time of onset of symptoms was not ascertained; however, the time of the onset of AKI was ascertained from changes in serum creatinine levels in patients who developed AKI during their hospitalization. We cannot exclude the possibility that lower NMN doses could be efficacious in patients with COVID‐19 and AKI. However, our cross‐sectional study of patients hospitalized with COVID‐19 revealed that NAD⁺ turnover was increased in patients with SARS‐CoV‐2 infection and NAD degrading enzymes, such as CD38 and PARPs, were markedly upregulated [16], suggesting that a higher dose of NMN might be needed in people with COVID‐19 to raise the NAD⁺ levels compared to healthy adults. Indeed, the steady state NAD⁺ levels in NMN‐treated patients with COVID‐19 were numerically lower than those observed in healthy adults. The patients with mild SARS‐CoV‐2 infection who were not hospitalized as well as those with severe disease who required invasive mechanical ventilatory support or admission to the intensive care unit were excluded, limiting the generalizability of the findings to hospitalized patients with moderately severe disease.

4. Conclusions

This is the first randomized controlled trial to demonstrate that oral administration of βNMN (MIB‐626) can safely and substantially increase the blood levels of NAD⁺ in patients hospitalized with COVID‐19. Among βNMN‐treated patients, blood NAD⁺ levels increased gradually and reached a peak level between days 5 and 14, but the plasma levels of its metabolites increased more rapidly. Changes in biomarkers of acute kidney injury, inflammation, and disease severity did not differ between groups, likely due to small sample size and slow ramp‐up of NAD⁺ levels. Future studies should assess whether a rapid increase in NAD⁺ by parenteral administration can attenuate disease severity and AKI in COVID‐19.

Author Contributions

S.B., K.M.P., D.J.L., and S.S.W. designed the trial; S.B. obtained the funding for the trial; D.E.L., R.J.V., T.S.M., E.V., D.F., T.J., N.K.L., S.L., S.K., Y.M.‐B., and S.K. performed research; K.M.P., T.S.M., T.J., and Y.V.S. analyzed the data; K.M.P. and S.B. wrote the first version of the paper; T.S.M. and T.J. developed the case report forms and the secure database; all other co‐authors reviewed the paper and provided critical feedback.

Conflicts of Interest

The authors have disclosed their other interests below, but none poses a conflict that would bias the findings of the trial that are included in this manuscript. Dr. Bhasin reports receiving research grants paid to his institution from the National Institute on Aging, the National Institute of Child Health and Human Development—National Center for Medical Rehabilitation Research, AbbVie, Metro International Biotech, and SBIR grant in collaboration with FPT; receiving consulting fees from Besins and Versanis; and equity interest in FPT. Drs. Livingston and Karmi are employees of Metro International Biotech. Dr. Lavu serves as a consultant to Metro International Biotech. Dr. Leaf received research support from BioPorto, BTG International, Metro International Biotech LLC, Renibus Therapeutics Inc., and Alexion Pharmaceuticals, has served as a consultant for Sidereal Therapeutics, Casma Therapeutics, MexBrain, Entrada Therapeutics, CardioRenal Systems Inc., and Alexion Pharmaceuticals, and served as a Co‐Chair of a Safety Monitoring Committee for EMD Serono Research and Development Institute Inc. Dr. Waikar reports receiving research grants paid to his institution from the National Institute on Aging, National Institutes of Diabetes, Digestive, and Kidney Diseases; Vertex, Pfizer, JNJ, and Natera; receiving consulting fees from Wolters Kluewer, Bain, BioMarin, Goldfinch, GSK, Ikena, Strataca, Google, CANbridge, NovoNordisk, Ono, PepGen, Sironax, NovoNordisk, Vertex, Mineralys, Motric Bio; and expert witness work on litigation related to dialysis lab testing (Davita), PPIs (Pfizer), PFAO exposure (Dechert), and a patent.

Supporting information

Data S1.

Pencina K. M., Leaf D. E., Valderrabano R. J., et al., “Oral MIB‐626 (β Nicotinamide Mononucleotide) Safely Raises Blood Nicotinamide Adenine Dinucleotide Levels in Hospitalized Patients With COVID‐19 and Acute Kidney Injury: A Randomized Controlled Trial,” FASEB BioAdvances 7, no. 8 (2025): e70011, 10.1096/fba.2025-00014.

Data Availability Statement

The de‐identified data that support the findings of this study can be made available upon review of a written request for noncommercial research use by writing to Dr. Shalender Bhasin at sbhasin@bwh.harvard.edu.