Palonosetron Hydrochloride (Page 2 of 7)

6.2 Postmarketing Experience

The following adverse reactions have been identified during postapproval use of palonosetron hydrochloride. 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.

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Hypersensitivity reactions: including dyspnea, bronchospasm, swelling/edema, erythema, pruritus, rash, urticaria, anaphylaxis and anaphylactic shock [see Warnings and Precautions (5.1) ]

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Injection site reactions: including burning, induration, discomfort and pain

7 DRUG INTERACTIONS

7.1 Serotonergic Drugs

Serotonin syndrome (including altered mental status, autonomic instability, and neuromuscular symptoms) has been described following the concomitant use of 5-HT₃ receptor antagonists and other serotonergic drugs, including selective serotonin reuptake inhibitors (SSRIs) and serotonin and noradrenaline reuptake inhibitors (SNRIs). Monitor for the emergence of serotonin syndrome. If symptoms occur, discontinue Palonosetron Hydrochloride and initiate supportive treatment [see Warnings and Precautions (5.2) ].

8 USE IN SPECIFIC POPULATIONS

8.1 Pregnancy

Risk Summary

There are no available data on palonosetron hydrochloride use in pregnant women to inform a drug-associated risk.

In animal reproduction studies, no effects on embryo-fetal development were observed with the administration of oral palonosetron hydrochloride during the period of organogenesis at doses up to 1,894 and 3,789 times the recommended human intravenous dose in rats and rabbits, respectively (see Data).

The estimated background risk of major birth defects and miscarriage for the indicated population is 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 to 4% and 15 to 20%, respectively.

Data

Animal Data

In animal reproduction studies, no effects on embryo-fetal development were observed in pregnant rats given oral palonosetron hydrochloride at doses up to 60 mg/kg/day (1,894 times the recommended human intravenous dose based on body surface area) or pregnant rabbits given oral doses up to 60 mg/kg/day (3,789 times the recommended human intravenous dose based on body surface area) during the period of organogenesis.

8.2 Lactation

Risk Summary

There are no data on the presence of palonosetron in human milk, the effects of palonosetron on the breastfed infant, or the effects of palonosetron on milk production. The developmental and health benefits of breastfeeding should be considered along with the mother’s clinical need for Palonosetron Hydrochloride and any potential adverse effect on the breastfed infant from palonosetron or from the underlying maternal condition.

8.4 Pediatric Use

Chemotherapy-Induced Nausea and Vomiting

Safety and effectiveness of Palonosetron Hydrochloride injection have been established in pediatric patients aged 1 month to less than 17 years for the prevention of acute nausea and vomiting associated with initial and repeat courses of emetogenic cancer chemotherapy, including HEC. Use is supported by a clinical trial where 165 pediatric patients aged 2 months to less than 17 years were randomized to receive a single dose of Palonosetron Hydrochloride injection 20 mcg/kg (maximum 1.5 mg) administered as an intravenous infusion 30 minutes prior to the start of emetogenic chemotherapy [see Clinical Studies (14.2) ]. While this study demonstrated that pediatric patients require a higher palonosetron dose than adults to prevent chemotherapy-induced nausea and vomiting, the safety profile is consistent with the established profile in adults [see Adverse Reactions (6.1) ].

Safety and effectiveness of Palonosetron Hydrochloride in neonates (less than 1 month of age) have not been established.

Postoperative Nausea and Vomiting Studies

Safety and effectiveness have not been established in pediatric patients for prevention of postoperative nausea and vomiting. Two pediatric trials were performed.

Pediatric Study 1, a dose finding study, was conducted to compare two doses of palonosetron, 1 mcg/kg (maximum 0.075 mg) versus 3 mcg/kg (maximum 0.25 mg). A total of 150 pediatric surgical patients participated, age range 1 month to less than 17 years. No dose response was observed.

Pediatric Study 2, a multicenter, double-blind, double-dummy, randomized, parallel group, active control, single-dose non-inferiority study, compared intravenous palonosetron hydrochloride (1 mcg/kg, maximum 0.075 mg) versus intravenous ondansetron. A total of 670 pediatric surgical patients participated, age 30 days to less than 17 years. The primary efficacy endpoint, Complete Response (CR: no vomiting, no retching, and no antiemetic rescue medication) during the first 24 hours postoperatively was achieved in 78.2% of patients in the palonosetron group and 82.7% in the ondansetron group. Given the pre-specified non-inferiority margin of -10%, the stratum adjusted Mantel-Haenszel statistical non-inferiority confidence interval for the difference in the primary endpoint, complete response (CR), was [-10.5, 1.7%], therefore non-inferiority was not demonstrated. Adverse reactions to palonosetron were similar to those reported in adults.

8.5 Geriatric Use

Of the 1374 adult cancer patients in clinical studies of intravenously administered palonosetron hydrochloride, 316 (23%) were 65 years and over, while 71 (5%) were at least 75 years and over. Of the 1520 adult patients in clinical studies of intravenously administered palonosetron hydrochloride, 73 (5%) were at least 65 years old [see Clinical Studies (14.1, 14.3)]. No overall differences in safety or effectiveness were observed between these subjects and younger subjects, but greater sensitivity in some older individuals cannot be ruled out. Population pharmacokinetics analysis did not reveal any differences in palonosetron pharmacokinetics between cancer patients 65 years of age and older compared to younger patients [see Clinical Pharmacology (12.3) ]. No dose adjustment is required for geriatric patients.

10 OVERDOSAGE

There is no known antidote to palonosetron. Overdose should be managed with supportive care.

Dialysis studies have not been performed, however, due to the large volume of distribution, dialysis is unlikely to be an effective treatment for palonosetron overdose. A single intravenous dose of palonosetron hydrochloride at 30 mg/kg (947 and 474 times the human dose for rats and mice, respectively, based on body surface area) was lethal to rats and mice. The major signs of toxicity were convulsions, gasping, pallor, cyanosis and collapse.

11 DESCRIPTION

Palonosetron Hydrochloride injection contains palonosetron as palonosetron hydrochloride, an antiemetic and antinauseant agent. It is a serotonin-3 (5-HT₃ ) receptor antagonist with a strong binding affinity for this receptor. Chemically, palonosetron hydrochloride is: (3a S)-2-[(S)-1-Azabicyclo [2.2.2]oct-3-yl]-2,3,3a,4,5,6-hexahydro-1-oxo-1H benz[de ]isoquinoline hydrochloride. The empirical formula is C₁₉ H₂₄ N₂ O.HCl, with a molecular weight of 332.87. Palonosetron hydrochloride exists as a single isomer and has the following structural formula:

Palonosetron hydrochloride is a white to off-white crystalline powder. It is freely soluble in water, soluble in propylene glycol, and slightly soluble in ethanol and 2-propanol.

Palonosetron Hydrochloride injection is a sterile, clear, colorless, non-pyrogenic, isotonic, buffered solution for intravenous administration. Palonosetron Hydrochloride injection is available as a 5 mL single-dose vial.

Each 5 mL vial contains: 0.25 mg palonosetron (equivalent to 0.28 mg palonosetron hydrochloride). Each mL of aqueous solution contains palonosetron hydrochloride equivalent to 0.05 mg palonosetron. Each mL also contains 41.5 mg mannitol, 0.5 mg edetate disodium dihydrate, 3.7 mg trisodium citrate dihydrate, 1.56 mg citric acid monohydrate, and water for injection (q.s. to 1.0 mL). Hydrochloric acid or sodium hydroxide may have been added to adjust pH.

The pH of the solution in the 5 mL vial is 4.5 to 5.5.