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Introducing NULIBRY, FDA-approved for patients with MoCD Type A to reduce the risk of mortality1

NULIBRY has been shown to reduce the risk of mortality in patients with molybdenum cofactor deficiency (MoCD) Type A. It is a cyclic pyranopterin monophosphate (cPMP) which replaces a critical component the body needs to make molybdenum cofactor (MoCo).

The efficacy of NULIBRY was evaluated in clinical studies where patients received NULIBRY or an Escherichia coli-derived non-salt, anhydrous form of cPMP (recombinant cPMP or rcPMP, which has the same active moiety and the same biologic activity as NULIBRY).

In children with MoCD Type A, NULIBRY (or rcPMP) was shown to:

  • Improve overall survival vs genotype-matched, untreated natural history controls
  • Reduce and maintain reductions of S-sulfocysteine (SSC)

NULIBRY comes as a lyophilized powder or cake in vials that must stay frozen until ready to be used. It is delivered via cold chain by a specialty pharmacy. A medical-grade freezer is needed to help ensure NULIBRY stays within the right storage temperature range. NULIBRY must be reconstituted before it is administered as a daily intravenous (IV) infusion.

Please see Important Safety Information below.

As soon as MoCD Type A is suspected, consider NULIBRY.

NULIBRY (or rcPMP) improved survival in patients with MoCD Type A1

Efficacy assessed in a combined analysis of the 13 patients with genetically confirmed MoCD Type A (MOCS1 mutation) from Study 1 (n=8), Study 2 (n=1), and Study 3 (n=4) who received substrate replacement therapy with NULIBRY (or rcPMP).

OS in patients with MoCD Type A treated with NULIBRY (or rcPMP) vs untreated, genotype-matched natural history controls1

Patients treated with NULIBRY or r c P M P demonstrated improved survival versus untreated patients

NULIBRY reduced the risk of death in patients with MoCD Type A1

Patients treated with NULIBRY or rcPMP had an improvement in overall survival (OS) compared to the untreated, genotype-matched, natural history controls. In these studies, NULIBRY or rcPMP reduced the risk of death by 82% compared to untreated, genotype-matched, natural history controls.

OS in patients with MoCD Type A treated with NULIBRY (or rcPMP) versus genotype-matched untreated patients in natural history control
Untreated, Genotype-Matched, Natural History Controls
Number of deaths (%) 2 (15%) 12 (67%)
50th Percentile (Median) Survival Time in Months (95% CI)a NE (16, NE) months 48 (10, 99) months
Kaplan-Meier Survival Probablity (95% CI)
1 year
3 years
92% (57%, 99%)
84% (49%, 96%)
67% (40%, 83%)
55% (30%, 74%)
Hazard Ratio for Risk of Death (95% CI)b 0.18 (0.04, 0.72)

CI=confidence interval; NE=not estimable; rcPMP=recombinant Escherichia coli-derived cPMP.

a Quartile estimates from product-limit (Kaplan-Meier) method, with associated log-log confidence intervals.

b Based on Cox proportional hazards model regressing survival status on an indicator variable denoting treatment status. The 95% CIs are based on the modified score test statistic under the Cox model. The hazard ratio represents the risk of death in the treated patients compared to the untreated historical control patients.

NULIBRY (or rcPMP) lowered SSC levels

  • Treatment with NULIBRY (or rcPMP) resulted in a reduction in the level of urinary SSC in patients with MoCD Type A, and this reduction was sustained with long-term treatment over 48 months
    • Baseline level of urinary SSC was 89.8 μmol/mmol (n=1)
    • Following treatment, the mean levels of urinary SSC ranged from 11.0 (±8.5) to 7.0 (±2.44) μmol/mmol from Month 3 to Month 48 (n=9)

NULIBRY demonstrated improved survival in patients with MoCD Type A.1

Common adverse reactions (>25%) reported in NULIBRY-treated patients with MoCD Type A.

Adverse Reactions NULIBRY-treated Patients (N=9)
n (%)
Catheter-related complications* 8 (89%)
Pyrexia 7 (78%)
Viral infection 5 (56%)
Pneumonia 4 (44%)
Otitis media 4 (44%)
Vomiting 4 (44%)
Cough/sneezing 4 (44%)
Viral upper respiratory infection 3 (33%)
Gastroenteritis 3 (33%)
Diarrhea 3 (33%)
Bacteremia 3 (33%)

*Catheter-related complications included complication associated with device, catheter site abscess, catheter site discharge, catheter site extravasation, catheter site pain, catheter site infection, catheter site inflammation, device dislocation, device leakage, device occlusion, and vascular device infection.

  • Adverse reactions for the rcPMP-treated patients were similar to the NULIBRY-treated patients, except for the following additional adverse reactions that were reported in more than one patient: sepsis, oral candidiasis, varicella, fungal skin infection, and eczema
  • The median exposure to NULIBRY was 4.3 years and ranged from 8 days to 5.6 years


  1. NULIBRY [prescribing information]
Preparing and
Administering NULIBRY >



NULIBRY is indicated to reduce the risk of mortality in patients with molybdenum cofactor deficiency (MoCD) Type A.



Potential for Photosensitivity

NULIBRY can make the patient oversensitive to sunlight. NULIBRY-treated patients or their caregivers are advised to avoid or minimize patient exposure to sunlight and artificial UV light and adopt precautionary measures when exposed to the sun, including wearing protective clothing and sunglasses, and use broad-spectrum sunscreen with high SPF in patients 6 months of age and older. If photosensitivity occurs, caregivers/patients are advised to seek medical attention immediately and consider a dermatological evaluation.


The most common side effects in NULIBRY-treated patients were infusion catheter–related complications, pyrexia (fever), viral infection, pneumonia, otitis media (ear infection), vomiting, cough/sneezing, viral upper respiratory infection (common cold/flu-like infection), gastroenteritis (stomach flu-like symptoms), diarrhea, and bacteremia (bacteria in the blood). Side effects for rcPMP-treated patients were similar to the NULIBRY-treated patients.


Please read the FDA-approved NULIBRY Prescribing Information and Instructions for Use and follow the instructions on how to prepare and administer NULIBRY.

NULIBRY has a potential for photosensitivity; see Warnings and Precautions. Seek medical attention immediately if the patient develops a rash or if they notice symptoms of photosensitivity reactions (redness, burning sensation of the skin, blisters).

You are encouraged to report negative side effects of prescription drugs to the FDA. Visit, or call 1-800-FDA-1088.

Please see full Prescribing Information for NULIBRY.