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Generic Name: lucinactant
Dosage Form: endotracheal suspension

Indications and Usage for Surfaxin

Surfaxin® (lucinactant) Intratracheal Suspension is indicated for the prevention of respiratory distress syndrome (RDS) in premature infants at high risk for RDS. Surfaxin reduces the incidence of RDS at 24 hours and mortality due to RDS.

Surfaxin Dosage and Administration

For intratracheal administration only.

Surfaxin should be administered by or under the supervision of clinicians experienced in intubation, ventilator management, and general care of premature infants.


The recommended dose of Surfaxin is 5.8 mL per kg birth weight. Up to 4 doses of Surfaxin can be administered in the first 48 hours of life. Doses should be given no more frequently than every 6 hours.

No information is available on doses greater than 5.8 mL per kg birth weight, the effects of more than 4 doses, or dosing more frequently than every 6 hours.

Dosage may be determined from Table 1.

Table 1. Dosing Chart

Birth Weight (g)     Total Dose (mL)     Birth Weight (g)     Total Dose (mL)
600-649     3.5     950-999     5.5
650-699     3.8     1000-1049     5.8
700-749     4.1     1050-1099     6.1
750-799     4.4     1100-1149     6.4
800-849     4.6     1150-1199     6.7
850-899     4.9     1200-1250     7.0
900-949     5.2                      

Directions for Use


Before use, warm the vial for 15 minutes in a preheated dry block heater set at 44°C (111°F). After warming, shake the vial vigorously until Surfaxin is a uniform and free-flowing suspension. The temperature of the product will be approximately 37°C (99°F) or less after the product is drawn into a syringe for administration.

For each vial of Surfaxin that is warmed, record the date and time of warming in the space provided on the carton. If not used immediately after warming, Surfaxin can be stored protected from light (i.e., in the carton) at room temperature for up to 2 hours. Do not return Surfaxin to the refrigerator after warming. Discard the product if not used within 2 hours of warming. Vials are for single use only. Discard any unused portion of Surfaxin.


Visually inspect Surfaxin before use. After being warmed and vigorously shaken, Surfaxin should be free-flowing and opaque white to off-white. Use aseptic technique to slowly draw up the appropriate amount of Surfaxin into a single, appropriately sized syringe, depending on the total dose volume, using a 16- or 18-gauge needle.

Before administering Surfaxin, assure proper placement and patency of the endotracheal tube. At the discretion of the clinician, the endotracheal tube may be suctioned before administering Surfaxin. The infant should be allowed to stabilize before proceeding with dosing.

Position the infant in the right lateral decubitus position with head and thorax inclined upward 30°. Attach the syringe containing Surfaxin to a 5-French end-hole catheter. Thread the catheter through a Bodai valve or equivalent device that allows maintenance of positive end-expiratory pressure and then advance the tip of the catheter into the endotracheal tube. Position the catheter such that its tip is slightly distal to the end of the endotracheal tube.

Each Surfaxin dose should be delivered in 4 aliquots. Instill the first aliquot of the dose (one-quarter of the total volume) as a bolus while continuing positive pressure mechanical ventilation and maintaining positive end-expiratory pressure of 4 to 5 cm H2O. Ventilator settings may be adjusted at the discretion of the clinician to maintain appropriate oxygenation and ventilation. Ventilate until the infant is stable, that is, has an oxygen saturation of at least 90% and a heart rate greater than 120 beats per minute. Repeat the procedure with the infant in the left decubitus position while maintaining adequate positive pressure ventilation. Repeat the procedure with the infant in the right, then left decubitus position to deliver a total of 4 aliquots. A pause should separate administration of the aliquots to allow for an evaluation of the infant’s respiratory status.

After instillation of the last aliquot, remove the catheter and resume usual ventilator management and critical care while keeping the head of the infant’s bed elevated at least 10 degrees for at least 1-2 hours. Do not suction the infant during the first hour after dosing unless signs of significant airway obstruction occur.

Use the same technique for additional doses, if indicated.

Dosage Forms and Strengths

Intratracheal Suspension: 8.5 mL suspension in a glass vial. Each mL contains 30 mg phospholipids [22.50 mg dipalmitoylphosphatidylcholine (DPPC) and 7.50 mg palmitoyloleoyl-phosphatidylglycerol, sodium salt (POPG, Na)], 4.05 mg palmitic acid (PA), and 0.862 mg sinapultide.



Warnings and Precautions

Acute Changes in Lung Compliance

Administration of exogenous surfactants, including Surfaxin, can rapidly affect lung compliance and oxygenation. Surfaxin should be administered only by clinicians trained and experienced in the resuscitation, intubation, stabilization, and ventilatory management of premature infants in a clinical setting with the capacity to care for critically ill neonates. Infants receiving Surfaxin should receive frequent clinical assessments so that oxygen and ventilatory support can be modified to respond to changes in respiratory status.

Administration-Related Adverse Reactions

Frequently occurring adverse reactions related to the administration of Surfaxin include bradycardia, oxygen desaturation, reflux of drug into the endotracheal tube (ETT), and airway/ETT obstruction. If any of these events occur, dosing with Surfaxin should be interrupted and the infant’s clinical condition assessed and stabilized. Suctioning of the ETT or reintubation may be required if airway obstruction persists or is severe. After the patient is stable, dosing may proceed with appropriate monitoring.

Increased Serious Adverse Reactions in Adults with ARDS

In a two-part clinical trial in adult patients with ARDS, compared to standard of care, patients who received lucinactant via segmental bronchoscopic lavage had an increased incidence of death, multi-organ failure, sepsis, anoxic encephalopathy, renal failure, hypoxia, pneumothorax, hypotension, and pulmonary embolism. Surfaxin is not indicated for use in the treatment of ARDS.

Adverse Reactions

Because clinical studies are conducted under widely varying conditions, adverse reaction rates observed in the clinical studies of a drug cannot be directly compared to rates in the clinical studies of another drug and may not reflect the rates observed in practice.

Clinical Trials Experience

Studies in Premature Infants at Risk for Respiratory Distress Syndrome

The safety data described below reflect exposure to Surfaxin at a dose of 5.8 mL per kg (up to 4 doses) administered in either 4 aliquots (Study 1) or 2 aliquots (Study 2) in 643 infants 32 weeks gestational age or less in 2 randomized double-blind, active-controlled clinical studies in which infants could receive up to 4 doses of surfactant intratracheally [see Clinical Studies (14) ]. Study 1 was conducted in 1294 premature infants who weighed between 600 g and 1250 g at birth and were 32 weeks or less in gestational age. Infants received 1 of 3 surfactants, Surfaxin (N = 524), colfosceril palmitate (N = 506), or beractant (N = 258). Study 2 was conducted in 252 premature infants who weighed between 600 g and 1250 g and were less than 29 weeks in gestational age. Infants received Surfaxin (N = 119) or poractant alfa (N = 124).

Comparator surfactants colfosceril palmitate and beractant were administered at the recommended doses (5.0 and 4.0 mL per kg, respectively) while the first dose of poractant alfa administered (2.2 mL per kg) was less than the recommended dose of 2.5 mL per kg. Any subsequent doses of poractant alfa were at the recommended 1.25 mL per kg dose.

Administration-related adverse reactions (endotracheal tube reflux, pallor, endotracheal tube obstruction, and need for dose interruption) were assessed in both Surfaxin controlled clinical studies. Overall, the incidence of administration-related adverse reactions was higher in infants who received Surfaxin compared to other surfactants (Table 2) and resulted in a greater proportion of infants treated with Surfaxin who experienced administration-related oxygen desaturation and bradycardia. For Study 1, oxygen desaturation was reported in 17%, 9%, and 13% and bradycardia for 5%, 2%, and 3% of infants treated with Surfaxin, colfosceril palmitate, and beractant, respectively. For Study 2, oxygen desaturation was reported in 8% and 2% and bradycardia in 3% and 2% of infants treated with Surfaxin and poractant alfa, respectively. These adverse reactions did not appear to be associated with an increased incidence of serious complications or mortality relative to the comparator surfactants (Table 3).

Table 2. Administration-Related Adverse Reactions in Surfaxin Controlled Clinical Studiesa

aTable includes only infants who received study treatment.
bIn Study 1 doses were administered in 4 aliquots.
cIn Study 2 doses were administered in 2 aliquots.
         Study 1b Study 2c
(N = 524)
(N = 506)
(N = 258)
(N = 119)
Poractant alfa
(N = 124)
Total Doses
994 1038 444 174 160
         Total Number of Events (Events per 100 Doses)
ETT Reflux 183 (18) 161 (16) 67 (15) 47 (27) 31 (19)
Pallor 88 (9) 46 (4) 38 (9) 18 (10) 7 (4)
Dose Interruption 87 (9) 46 (4) 30 (7) 7 (4) 2 (1)
ETT Obstruction 55 (6) 21 (2) 19 (4) 27 (16) 1 (1)

Table 3. Common Serious Complications Associated with Prematurity and RDS in Surfaxin Controlled Clinical Studies Through 36-Weeks Post-Conceptual Age (PCA)

         Study 1 Study 2
(N = 527)
(N = 509)
(N = 258)
(N = 119)
(N = 124)
Apnea 52 52 46 66 75
Intraventricular hemorrhage, all grades 52 57 54 39 38
     - Grade 3/4 19 18 21 13 8
Periventricular leukomalacia 10 10 12 4 9
Acquired sepsis 44 44 44 45 52
Patent ductus arteriosus 37 35 37 43 44
Retinopathy of prematurity, all grades 27 26 25 32 31
     -Grade 3/4 6 7 6 5 9
Necrotizing enterocolitis, all grades 17 17 19 13 15
     -Grade 2/3 6 8 14 8 8
Pulmonary air leak through Day 7, all types 15 17 14 9 7
     -Pulmonary interstitial emphysema 9 10 10 3 5
     -Pneumothorax 3 4 2 4 1
Pulmonary hemorrhage 10 12 14 6 9

All-cause mortality through 36-weeks PCA was similar regardless of which exogenous surfactant was administered.

Adverse reactions reported in the controlled clinical studies through 36-weeks PCA occurring in at least 10% of infants were anemia, jaundice, metabolic acidosis, oxygen desaturation, hyperglycemia, pneumonia, hyponatremia, hypotension, respiratory acidosis, and bradycardia. These reactions occurred at rates similar to the comparator surfactants.

No assessments for immunogenicity to Surfaxin were performed in these clinical studies.

Follow-up Evaluations

Twelve-month corrected-age follow-up of 1546 infants enrolled in the 2 controlled clinical studies demonstrated no significant differences in mortality or gross neurologic findings between infants treated with Surfaxin and those treated with the comparator surfactants (colfosceril palmitate, beractant, or poractant alfa).

Clinical Study in Adults with ARDS

The safety and efficacy of lucinactant administered in 2 doses separated by 48 hours via segmental bronchoscopic lavage in adults with ARDS was evaluated in a two-part clinical trial in 124 adult patients. Twenty-two patients were studied in the initial open-label portion of the trial (Part A) and 102 patients participated in a subsequent randomized controlled portion (Part B). Compared to standard of care, patients who received treatment with lucinactant via segmental bronchoscopic lavage at doses up to 50 mL per lung segment had an increased incidence of death, multi-organ failure, sepsis, anoxic encephalopathy, renal failure, hypoxia/decreased oxygen saturation, pneumothorax, hypotension, and pulmonary embolism compared to those patients receiving standard of care. Surfaxin is not indicated for use in the treatment of ARDS.


There have been no reports of overdose following the administration of Surfaxin.

If respiration, ventilation, or oxygenation is clearly affected after an accidental overdose, aspirate as much of the suspension as possible and provide the infant with supportive treatment.

Surfaxin Description

Surfaxin (lucinactant) Intratracheal Suspension is a sterile, non-pyrogenic pulmonary surfactant intended for intratracheal use only. It is a synthetic formulation consisting of phospholipids, a fatty acid, and sinapultide (KL4 peptide), a 21-amino acid hydrophobic synthetic peptide. The chemical names, structures, and empirical formulas of the 4 active components of Surfaxin are:

Sinapultide (KL4 acetate)

Chemical Name: L - Lysyl - L - leucyl - L - leucyl - L - leucyl - L - leucyl - L - lysyl - L - leucyl - L - leucyl - L - leucyl - L - leucyl - L - lysyl - L - leucyl - L - leucyl - L - leucyl - L - leucyl - L - lysyl - L - leucyl - L - leucyl - L - leucyl - L - leucyl - L - lysine, acetate


Empirical Formula: C126H238N26O22               Molecular Weight: 2469.46


Chemical Name: 1,2-dipalmitoyl-sn-glycero-3-phosphocholine


Empirical Formula: C40H80NO8P               Molecular Weight: 734.06


Chemical Name: 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphoglycerol, sodium salt


Empirical Formula: C40H76O10PNa               Molecular Weight: 771.00


Chemical Name: Palmitic acid (hexadecanoic acid)


Empirical Formula: C16H32O2               Molecular Weight: 256.43

Surfaxin is a white to off-white opaque gel-like suspension at 2° to 8°C (36° to 46°F), which becomes a free-flowing suspension upon warming for 15 minutes in a dry block heater set at 44°C (111°F). Each mL of Surfaxin provides 30 mg phospholipids (22.50 mg DPPC and 7.50 mg POPG, Na), 4.05 mg PA, and 0.862 mg sinapultide in tromethamine and sodium chloride. Glacial acetic acid is used to adjust the pH of the buffer to 7.4 (range 7.0 to 8.0). Surfaxin contains no preservatives.

Surfaxin - Clinical Pharmacology

Mechanism of Action

Endogenous pulmonary surfactant lowers surface tension at the air-liquid interface of the alveolar surfaces during respiration and stabilizes the alveoli against collapse at resting transpulmonary pressures. A deficiency of pulmonary surfactant in premature infants results in RDS. Surfaxin compensates for the deficiency of surfactant and restores surface activity to the lungs of these infants.


In vitro

Lucinactant lowers minimum surface tension to ≤ 6 dynes per cm, as assessed by the pulsating bubble surfactometer.

In vivo

Lucinactant improves lung compliance and respiratory gas exchange in premature fetal rabbits, lambs and non-human primates with RDS under experimental conditions with controlled airflow and oxygen pressure. The clinical relevance of these animal findings to humans is unknown.


Surfaxin is administered directly to the lung, where biophysical effects occur at the terminal airways and alveolar surface. No human pharmacokinetic studies have been performed to characterize the absorption, distribution, metabolism, or elimination of Surfaxin.

Nonclinical Toxicology

Carcinogenesis, Mutagenesis, Impairment of Fertility

Studies to assess potential carcinogenic effects of Surfaxin have not been conducted.

Lucinactant was not mutagenic in the bacterial reverse mutation assay (Ames test), chromosomal aberration assay in Chinese hamster ovary cells, or mouse micronucleus assay.

No studies to assess reproductive effects of Surfaxin have been performed.

Clinical Studies

Prevention of Neonatal Respiratory Distress Syndrome

The efficacy and safety of Surfaxin for the prevention of RDS in premature infants was demonstrated in a single randomized, double-blind, multicenter, active-controlled, multi-dose study involving 1294 premature infants (Study 1). This study included 646 males and 648 females who weighed between 600 g and 1250 g at birth and were 32 weeks or less in gestational age. Seventy-eight percent of the infants were white, 1% black, and 21% classified as other. Study participants were from Europe and Latin America. Within the first 30 minutes after birth, infants were randomized to receive 1 of 3 surfactants, Surfaxin (N = 527), colfosceril palmitate (N = 509), or beractant (N = 258). Surfaxin was administered at a dose of 5.8 mL per kg, colfosceril palmitate at a dose of 5.0 mL per kg, and beractant at a dose of 4.0 mL per kg. Infants in the Surfaxin and beractant groups could be given up to 3 additional doses between 6 and 24 hours of birth, as often as every 6 hours, if they subsequently developed RDS and required mechanical ventilation with an FiO2 ≥ 0.30 and a mean airway pressure (MAP) ≥ 6 cm H2O. Infants in the colfosceril palmitate group could receive up to 2 additional doses at least 12 hours apart if they met the retreatment criteria. Some infants received sham air to maintain blinding of the study. All doses were calculated based on birth weight. Infants were followed through 12-months corrected age.

Co-primary endpoints were the incidence of RDS (defined as having a chest x-ray consistent with RDS and an FiO2 ≥ 0.30) at 24 hours and RDS-related mortality at 14 days. The primary comparison of interest was between Surfaxin and colfosceril palmitate with the intent of demonstrating superiority. Beractant served as an additional active comparator. Compared to colfosceril palmitate, Surfaxin demonstrated a statistically significant improvement in both RDS at 24 hours and RDS-related mortality through Day 14. Results for the primary endpoint comparisons and other relevant endpoints are shown in Table 4.

Table 4. Results from a Controlled Prophylaxis Study in Preterm Infants (Study 1)

(N = 527)
n (%)
(N = 509)
n (%)
vs. Colfosceril
RDS at 24 hours 206 (39) 240 (47) <0.01
RDS-related mortality through Day 14 25 (5) 48 (9) <0.01
Non-RDS-related mortality through Day 14 59 (11) 37 (7) 0.04
      Sepsis-related mortality through Day 14 21 (4) 17 (3) 0.70
All-cause mortality      
      Through Day 28 100 (19) 108 (21) 0.23
      Through 36-weeks PCA 111 (21) 121 (24) 0.18
Pulmonary air leak through Day 7, all types 82 (16) 93 (18) 0.15
Oxygen requirement      
      At Day 28 304 (58) 316 (62) 0.06
      At 36-weeks PCA 210 (40) 227 (45) 0.05

A second multicenter, double-blind, active-controlled study involving 252 premature infants was also conducted (Study 2). The study included 126 males and 126 females who weighed between 600 g and 1250 g at birth with a gestational age ≥ 24 weeks but < 29 weeks. Eighty-three percent of the infants were white and 5% black. Study participants were from North America and Europe. Within the first 30 minutes after birth, infants were randomized to receive 1 of 2 surfactants, Surfaxin (N = 124) or poractant alfa (N = 128). Surfaxin was administered at a dose of 5.8 mL per kg and poractant alfa was dosed at 2.2 mL per kg for the first dose and 1.25 mL per kg for subsequent doses. Infants in each group could be given up to 2 additional doses during the first 48 hours of life if they continued to require mechanical ventilation with an FiO2 ≥ 0.30 to maintain arterial PaO2 ≥ 50 mmHg or an oxygen saturation ≥ 90% and a chest radiograph consistent with RDS. The primary endpoint was the incidence of being alive without bronchopulmonary dysplasia at Day 28 of life. Bronchopulmonary dysplasia was defined as a requirement for mechanical ventilation or use of supplemental oxygen in order to maintain oxygen saturation ≥ 90%. The study was designed with the intent of demonstrating non-inferiority between Surfaxin and poractant alfa with a planned sample size of 248 infants per treatment group. However, the basis of the non-inferiority margin could not be justified; the study was also terminated prematurely. As such, Study 2 can only be used to support the safety of Surfaxin relevant to another surfactant product.

There is no controlled experience with the use of Surfaxin in conjunction with experimental therapies for RDS (e.g., high-frequency ventilation or extracorporeal membrane oxygenation).

How Supplied/Storage and Handling

Surfaxin (lucinactant) Intratracheal Suspension is supplied sterile in single-use, rubber stoppered, clear glass vials containing 8.5 mL of white suspension (NDC 68628-500-31). One vial per carton.

Store Surfaxin in a refrigerator at 2° to 8°C (36° to 46°F) and protect from light until ready for use. Do not freeze. Vials are for single use only. Discard any unused portion of Surfaxin. Discard warmed vials of Surfaxin if not used within 2 hours of warming [see Directions for Use (2.2)].

Manufactured by Discovery Laboratories, Inc.
Warrington, PA 18976

Copyright © 2012 Discovery Laboratories, Inc. All rights reserved.

U.S. Patent

Surfaxin, DISCOVERYLABS and INSPIRED INNOVATION are registered trademarks of Discovery Laboratories, Inc.


Principal Display Panel - Surfaxin Package - 8.5 mL Vial Label

Principal Display Panel - Surfaxin Package - 8.5 mL Vial Carton

lucinactant suspension
Product Information
Product Type HUMAN PRESCRIPTION DRUG LABEL Item Code (Source) NDC:68628-500
Route of Administration ENDOTRACHEAL DEA Schedule     
Active Ingredient/Active Moiety
Ingredient Name Basis of Strength Strength
Inactive Ingredients
Ingredient Name Strength
TROMETHAMINE 2.42 mg  in 1 mL
SODIUM CHLORIDE 7.60 mg  in 1 mL
Product Characteristics
Color WHITE (White to Off-White) Score     
Shape Size
Flavor Imprint Code
# Item Code Package Description
1 NDC:68628-500-31 1 VIAL, SINGLE-USE in 1 CARTON
1 8.5 mL in 1 VIAL, SINGLE-USE
Marketing Information
Marketing Category Application Number or Monograph Citation Marketing Start Date Marketing End Date
NDA NDA021746 11/01/2013
Labeler - Discovery Laboratories, Inc. (171938970)
Name Address ID/FEI Operations
Discovery Laboratories, Inc. 171938970 MANUFACTURE(68628-500)
Revised: 04/2014
Discovery Laboratories, Inc.