Risk Summary
PROVAYBLUE
® may cause fetal harm when administered to a pregnant woman. Intra-amniotic injection of pregnant women with a methylene blue class product during the second trimester was associated with neonatal intestinal atresia and fetal death. Methylene blue produced adverse developmental outcomes in rats and rabbits when administered orally during organogenesis at doses at least 32 and 16 times, respectively, the clinical dose of 1 mg/kg
[see
Data]
. Advise pregnant women of the potential risk to a fetus.
In the U.S. general population, the estimated background risks of major birth defects and miscarriage in clinically recognized pregnancies are 2-4% and 15-20%, respectively.
Clinical Considerations
Fetal/neonatal adverse reactions
Intra-amniotic injection of a methylene blue class product hours to days prior to birth can result hyperbilirubinemia, hemolytic anemia, skin staining, methemoglobinemia, respiratory distress and photosensitivity in the newborn. Following administration of PROVAYBLUE
® to a pregnant woman at term, observe the newborn for these adverse reactions and institute supportive care.
Data
Animal Data
Methylene blue was administered orally to pregnant rats at doses of 50 to 350 mg/kg/day, during the period of organogenesis. Maternal and embryofetal toxicities were observed at all doses of methylene blue, and were most evident at the 200 and 350 mg/kg/day doses. Maternal toxicity consisted of increased spleen weight. Embryo-fetal toxicities included reduced fetal weight, post-implantation loss, edema, and malformations including enlarged lateral ventricles. The dose of 200 mg/kg (1200 mg/m
2) in rats is approximately 32 times a clinical dose of 1 mg/kg based on body surface area.
Methylene blue was administered orally to pregnant rabbits at doses of 50, 100, or 150 mg/kg/day, during the period of organogenesis. Maternal death was observed at the methylene blue dose of 100 mg/kg. Embryofetal toxicities included spontaneous abortion at all dose levels and a malformation (umbilical hernia) at the 100 and 150 mg/kg/day doses. The dose of 50 mg/kg (600 mg/m
2) in rabbits is approximately 16 times a clinical dose of 1 mg/kg based on body surface area.
Risk Summary
There is no information regarding the presence of methylene blue in human milk, the effects on the breastfed infant, or the effects on milk production. Because of the potential for serious adverse reactions, including genotoxicity discontinue breast-feeding during and for up to 8 days after treatment with PROVAYBLUE
®[see Clinical Pharmacology (
12.3)]
.
Cardiac Electrophysiology
The results of a thorough QT study demonstrated PROVAYBLUE
® at an intravenous dose of 2 mg/kg as a 5-minute intravenous infusion had no effect on the QT, PR or QRS intervals.
Distribution
The mean± standard deviation steady state volume of distribution of a 2 mg/kg dose of PROVAYBLUE
® was 255 L ± 58. The mean plasma protein binding of methylene blue is approximately 94% in vitro. Methylene blue exhibits concentration-dependent partitioning into blood cells in vitro. The blood-to-plasma ratio was 5.1±2.8 at 5 minutes from the start of a 2 mg/kg dose administered as a 5-minute intravenous infusion and reached a plateau of 0.6 at 4 hours in a clinical study. Methylene Blue is a substrate for the P-glycoprotein (P-gp, ABCB1) transporter, but not for BCRP or OCT2 in vitro.
Elimination
Methylene blue has a half-life of approximately 24 hours.
Metabolism
Methylene blue is metabolized by CYPs 1A2, 2C19 and 2D6 in vitro; however, the predominant in vitro pathway appears to be UGT-mediated conjugation by multiple UGT enzymes, including UGT1A4 and UGT1A9.
Azure B, which is a minor impurity in methylene blue, is also formed in humans as a metabolite of methylene blue, with an overall drug/metabolite AUC ratio of greater than 6:1. Azure B has 8-fold lower potency than methylene blue.
Excretion
Approximately 40% of methylene blue is excreted in to the urine unchanged.
Drug Interaction Studies
The clinical relevance of in vitro inhibition or induction of the metabolizing enzymes and transporter systems described below is unknown, but it cannot be excluded that the systemic exposure of medicinal products being substrates for these enzymes or transporter systems may be affected with concomitant administration with PROVAYBLUE
® Injection.
Cytochrome P450
Methylene blue inhibits CYP isozymes 1A2, 2B6, 2C8, 2C9, 2C19, 2D6 and 3A4/5 in vitro. Possible time-dependent inhibition of CYP2C9, CYP2D6 and CYP3A4/5 (testosterone as substrate) was also observed in vitro. Methylene blue induces CYP1A2, but does not induce CYP2B6 or CYP3A4 in vitro.
Glucuronosyltransferase
Methylene blue inhibits UGT1A9 and UGT1A4 in in vitro, but did not significantly inhibit UGTs 1A1, 1A3, 1A6, 2B7 or 2B15.
Transporter Interactions
Methylene blue is both a substrate for and an inhibitor of P-gp, but is not a substrate for BCRP or OCT2 in vitro. Methylene blue is not a significant inhibitor of BCRP, OAT1, OAT3, OAT1B1 or OAT1B3 in vitro. Methylene blue inhibits OCT2, MATE1 and MATE2-K in vitro. The OCT2/MATE pathway for renal transport is reported to play a significant role in the elimination of several substances, including metformin, cimetidine, acyclovir and creatinine
Serotonin Syndrome
Advise patients of the possibility of serotonin syndrome, especially with concomitant use of serotonergic agents such as medications to treat depression and migraines. Advise patients to seek immediate medical attention if the following symptoms occur after treatment with PROVAYBLUE
®: changes in mental status, autonomic instability, or neuromuscular symptoms with or without gastrointestinal symptoms
[see Warnings and Precautions (
5.1)].
Pregnancy
Advise pregnant women of the potential risk to the fetus with the use of PROVAYBLUE
® during pregnancy
[see Use in Specific populations (
8.1)].
Breastfeeding
Advise patients to discontinue breast-feeding for up to 8 days after treatment with PROVAYBLUE
®[see Use in Specific populations (
8.2)]
.
Driving and Using Machines
Advise patients to avoid driving and use of machines during treatment with PROVAYBLUE
®. Driving can be affected as a result of a confusional state, dizziness and possible eye disturbances
[see Warnings and Precautions (
5.6)]
.
Phototoxicity
Advise patients to take protective measures against exposure to light, because phototoxicity may occur after administration of methylene blue
[see Adverse Reactions (
6.1)]
.
Skin and Body Fluid Blue Discoloration
Advise patients that PROVAYBLUE
® may cause a blue discoloration of the skin and body fluids
[see Adverse Reactions (
6.1)].
Manufactured for:
PROVEPHARM SAS
22 rue Marc Donadille
13013 Marseille, France
Manufactured by:
CENEXI
52 rue Marcel et Jacques Gaucher
94120 Fontenay sous Bois, FRANCE
Distributed by:
American Regent, Inc.
Shirley, NY
Questions? : 1-800-734-9236
12/2017
[controlled part number code]