Aminolevulinic Acid Hydrochloride

Gleolan is indicated in patients with glioma [suspected World Health Organization (WHO) Grades III or IV on preoperative imaging] as an adjunct for the visualization of malignant tissue during surgery. Gleolan is an optical imaging agent indicated in patients with glioma (suspected World Health Organization Grades III or IV on preoperative imaging) as an adjunct for the visualization of malignant tissue during surgery. ( 1 )

For oral solution: 1,500 mg aminolevulinic acid hydrochloride (ALA HCl) lyophilized powder, equivalent to 1,170 mg aminolevulinic acid (ALA) , in a 50 mL single-dose clear, colorless, glass vial with rubber stopper. After reconstitution with 50 mL drinking water, the solution contains 30 mg per mL of aminolevulinic acid hydrochloride (equivalent to 23.4 mg per mL of aminolevulinic acid) and is clear and colorless to slightly yellowish in color. For oral solution: 1,500 mg aminolevulinic acid hydrochloride lyophilized powder, equivalent to 1,170 mg aminolevulinic acid per vial. The reconstituted aminolevulinic acid hydrochloride solution contains 30 mg per mL and is clear and colorless to slightly yellowish in color. ( 3 )

Hypersensitivity to the aminolevulinic acid (ALA) or porphyrins. [see Warnings and Precautions (5.3) ] Acute or chronic types of porphyria, due to potential ineffectiveness of the drug in these patients. Hypersensitivity to aminolevulinic acid (ALA) or porphyrins. ( 4 , 5.3 , 6.2 ) Acute or chronic types of porphyria. ( 4 )

Phototoxic reactions: Do not administer phototoxic drugs (St. John's wort, griseofulvin, thiazide diuretics, sulfonylureas, phenothiazines, sulphonamides, quinolones and tetracyclines), and topical preparations containing ALA for 24 hours during the perioperative period. Reduce exposure to sunlight or room lights for 48 hours after oral administration of Gleolan. ( 5.1 , 7 ) Risk of misinterpretation: Non-fluorescing tissue in the surgical field does not rule out the presence of tumor. ( 5.2 , 14 )

5.1 Risk of Phototoxic Reaction Due to the risk of phototoxic reactions, do not administer phototoxic drugs (St. John's wort, griseofulvin, thiazide diuretics, sulfonylureas, phenothiazines, sulphonamides, quinolones and tetracyclines), and topical preparations containing ALA for 24 hours during the perioperative period [see Drug Interactions (7) ] . Reduce exposure to sunlight or room lights for 48 hours after administration of Gleolan.

5.2 Risk of Misinterpretation Errors may occur with the use of Gleolan for intraoperative visualization of malignant glioma, including false negatives and false positives. Non-fluorescing tissue in the surgical field does not rule out the presence of tumor in patients with glioma [see Clinical Studies (14) ] . Fluorescence may be seen in areas of inflammation or metastases from other tumor types.

5.3 Hypersensitivity Reactions Hypersensitivity reactions, including serious hypersensitivity reactions have occurred; these reactions include anaphylactic shock, swelling, and urticaria [see Contraindications (4) , Adverse Reactions (6.2) ] . Always have cardiopulmonary resuscitation personnel and equipment readily available and monitor all patients for hypersensitivity reactions.

Adverse reactions occurring in >1% of patients in the week following surgery were pyrexia, hypotension, nausea, and vomiting. ( 6.1 ) Adverse reactions occurring in < 1% of patients in the first 6 weeks after surgery were: chills, photosensitivity reaction, solar dermatitis, hypotension, abnormal liver function test, and diarrhea. ( 6.1 ) Neurologic events related to the surgical procedure occurred in 29% of patients and included: aphasia, hemiparesis, hemianopia, headache, seizure, hemiplegia, monoparesis, hypoesthesia, and brain edema. ( 6.1 ) Elevated liver enzymes occurred in clinical studies. There were no cases of liver failure. ( 6.1 ) To report SUSPECTED ADVERSE REACTIONS, contact NXDC toll-free at (844) 517-5252 and adverseevents@nxdevcorp.com or FDA at 1-800-FDA-1088 or www.fda.gov/medwatch.

6.1 Clinical Trial Experience Because clinical trials are conducted under widely varying conditions, adverse reaction rates observed in the clinical trials of a drug cannot be directly compared to rates in the clinical trials of another drug and may not reflect the rates observed in practice. The safety of Gleolan is supported by data from 5 open label clinical studies, which included 527 patients with glioma who received ALA HCl. Adverse reactions that occurred in > 1% of patients in the week following surgery were pyrexia, hypotension, nausea, and vomiting. Adverse reactions occurring in the first 6 weeks after surgery in < 1% of patients were: chills, photosensitivity reaction, solar dermatitis, hypotension, abnormal liver function test, and diarrhea. One patient experienced respiratory failure due to drug overdose [see Overdosage (10) ] . Neurologic Events Nervous system disorders occurred in 29% of patients within the first week after surgery. Events occurring in > 1% of patients included aphasia (8%), hemiparesis (7.8%), hemianopsia (3.2%), headache (2.7%), seizure (1.9%), hemiplegia (1.9%), monoparesis (1.3%) and hypoesthesia (1.1%). Brain edema occurred in < 1 % of patients in the first 6 weeks after surgery. In a randomized clinical trial (Study 3), the numbers of serious neurologic adverse events in the post operative period were higher in patients randomized to ALA fluorescence arm compared to the control arm. An imbalance was notable for the adverse events aphasia, ataxia, convulsion and hemianopsia, and is likely related to the higher amount of brain resection performed in the ALA arm. At longer follow up periods, the numbers between the two arms appeared similar [see Clinical Trials (14) ] . Elevated Liver Enzymes Worsening of ≥ 2 Common Toxicity Criteria (CTC) grades in alanine aminotransferase (ALT) and gamma-glutamyl transferase (GGT) occurred in (15.8% and 11.6%, respectively) within the first week after surgery. Absolute levels ranged from 2 times to greater than 10 times the upper limit of normal (ULN) for each parameter. At 6 weeks, ALT remained elevated in 2.9% of patients (range 2 to greater than 5 X ULN), and GGT was elevated in 7.5% of patients (range 2 to greater than 10 X ULN). No cases of liver failure occurred.

6.2 Post Marketing Experience The following adverse reactions are among those that have been identified during post-approval use of Gleolan outside of the United States. Because these reactions are reported voluntarily from a population of uncertain size, it is not always possible to reliably estimate their frequency or establish a causal relationship to drug exposure. Immune Disorders : anaphylactic shock, angioedema, drug eruption, urticaria, erythema. Metabolism and Nutrition Disorders : metabolic acidosis.

Phototoxic Drugs Patients exposed to a photosensitizing agent may experience a phototoxic skin reaction (severe sunburn). Due to the risk of possible phototoxic reactions, avoid administering phototoxic drugs such as St. John's wort, griseofulvin, thiazide diuretics, sulfonylureas, phenothiazines, sulphonamides, quinolones and tetracyclines, and topical preparations containing ALA for 24 hours before and after administration of Gleolan.

8.1 Pregnancy Risk Summary There are no available human data on Gleolan in pregnant women to inform a drug associated risk of adverse developmental outcomes. In animal reproduction studies, no adverse developmental effects were observed with oral ALA HCl administration to pregnant rabbits during organogenesis at doses 3 times the maximum recommended human oral dose (see Data) . The estimated background risk of major birth defects and miscarriage for the indicated populations are unknown. All pregnancies have a background risk of birth defect, loss, or other adverse outcomes. In the U.S. general population, the estimated background risk of major birth defects and miscarriage in clinically recognized pregnancies is 2-4% and 15-20%, respectively. Animal data ALA HCl was administered to rabbits at oral doses of 15, 50 and 150 mg/kg/day [approximately 0.1, 0.6, and 3 times the maximum human recommended dose (MHRD), respectively based on AUC comparisons] from gestation days 6-18. The no-observed-adverse-effect level (NOAEL) for maternal toxicity was 50 mg/kg/day and the NOAEL for embryo-fetal developmental toxicity was 150 mg/kg/day.

8.2 Lactation Risk summary There are no data on the presence of ALA HCl in either human or animal milk, the effects on the breastfed infant, or the effects on milk production. The developmental and health benefits of breastfeeding should be considered along with the mother's clinical need for Gleolan and any potential adverse effects on the breastfed infant from Gleolan or from the underlying maternal condition. Clinical Considerations To decrease exposure to Gleolan to the breastfed infant, advise a lactating woman to pump and discard breast milk after the administration of Gleolan for 24 hours (i.e., 5 to 6 half-lives).

8.4 Pediatric Use The safety and effectiveness of Gleolan in pediatric patients have not been established.

8.5 Geriatric Use Of 527 subjects in clinical studies of Gleolan, 182 were 65 to < 75 years of age and 7 were ≥ 75 years of age. No overall differences in safety or effectiveness were observed between these subjects and younger subjects, and other reported clinical experience has not identified differences in responses between the elderly and younger patients, but greater sensitivity of some older individuals cannot be ruled out. No dose adjustment is required in elderly patients.

8.6 Patients with Renal Impairment Because approximately one third of the ALA dose is excreted in urine as parent drug, ALA clearance may be reduced in patients with renal impairment; it is not known if dose adjustment is needed [see Clinical Pharmacology (12.3) ] .

8.7 Patients with Hepatic Impairment The contribution of the liver to the elimination of ALA following Gleolan dosing is unknown. ALA clearance may be reduced in patients with hepatic impairment; it is not known if dose adjustment is needed [see Clinical Pharmacology (12.3) ] .

ALA occurs endogenously as a metabolite that is formed in the mitochondria from succinyl-CoA and glycine. Exogenous administration of ALA leads to accumulation of the ALA metabolite PpIX in tumor cells. The reason for the accumulation of PpIX in neoplastic brain tissue is not known. During glioma surgery, Gleolan is used with an operating microscope adapted with a blue emitting light source (power density 40-80 mW/cm 2 ) and filters for excitation light of wavelength 375 to 440 nm, and observation at wavelengths of 620 to 710 nm. This allows tumor tissue to be visualized as red fluorescence. Tissue lacking sufficient PpIX concentrations appears blue.