Firazyr

Overdose

In a clinical study evaluating a 90 mg dose (30 mg in each of 3 subcutaneous sites), the adverse event profile was similar to that seen with 30 mg administered in a single subcutaneous site.

In another clinical study, a dose of 3.2 mg/kg administered intravenously (approximately 8 times the therapeutic dose for HAE) caused erythema, itching and hypotension in healthy subjects. No therapeutic intervention was necessary.

Contraindications

None.

Undesirable effects

The safety of icatibant was evaluated in three controlled trials that included 223 patients who received FIRAZYR 30 mg (n=113), placebo (n=75), or comparator (n=38). The mean age at study entry was 38 years (range 18 to 83 years), 64% were female, and 95% were white. The data described below represent adverse reactions observed from the two placebo-controlled trials, consisting of 77 patients who received FIRAZYR at a dose of 30 mg SC, and 75 who received placebo.

The most frequently reported adverse reactions (occurring in greater than 1% of patients and at a higher rate with FIRAZYR versus placebo) are shown in Table 1.

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.

Table 1 : Adverse reactions observed in > 1% of patients with acute attacks of HAE and at a higher rate with FIRAZYR versus placebo in the placebo-controlled trialsa

The third trial was active-controlled and was comprised of 35 patients who received FIRAZYR 30 mg and 38 patients who received the comparator. Adverse reactions for FIRAZYR were similar in nature and frequency to those reported in Table 1.

In all three controlled trials, patients were eligible for treatment of subsequent attacks in an open-label extension. Patients were treated with FIRAZYR 30 mg and could receive up to 3 doses of FIRAZYR 30 mg administered at least 6 hours apart for each attack. A total of 225 patients were treated with 1,076 doses of 30 mg FIRAZYR for 987 attacks of acute HAE. Adverse reactions similar in nature and frequency were observed to those seen in the controlled phase of the trials. Other adverse reactions reported included rash, nausea, and headache in patients exposed to FIRAZYR.

The safety of self-administration was evaluated in a separate, open-label trial in 56 patients with HAE. In this trial, the safety profile of FIRAZYR in patients who self-administered FIRAZYR was similar in nature and frequency to that of patients whose therapy was administered by healthcare professionals.

Across repeated treatment in the controlled trials, 4 patients tested positive for anti-icatibant antibodies. Three of these patients had subsequent tests which were negative. No hypersensitivity or anaphylactic reactions were reported with FIRAZYR. No association between anti-icatibant antibodies and efficacy was observed.

Similar adverse reactions have been observed in postmarketing use as compared to the clinical trials. Because these events 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.

Therapeutic indications

FIRAZYR® (icatibant) is indicated for the treatment of acute attacks of hereditary angioedema (HAE) in adults 18 years of age and older.

Pharmacodynamic properties

Following bradykinin challenge, intravenous administration of FIRAZYR caused dose and time-dependent inhibition of development of bradykinin-induced hypotension, vasodilation, and reflex tachycardia in healthy young subjects. FIRAZYR intravenous doses of 0.4 and 0.8 mg/kg infused over 4 hours inhibited response to bradykinin challenge for 6 to 8 hours following completion of the infusion. Based on exposure-response analysis, a subcutaneous dose of 30 mg FIRAZYR is predicted to be effective against bradykinin challenge for at least 6 hours. The clinical significance of these findings is unknown.

The effect of FIRAZYR 30 and 90 mg following a single subcutaneous injection on QTc interval was evaluated in a randomized, placebo-, and active-controlled (moxifloxacin 400 mg) four-period crossover thorough QT study in 72 healthy subjects. In a study with demonstrated ability to detect small effects, the upper bound of the one-sided 95% confidence interval for the largest placebo adjusted, baseline-corrected QTc based on individual correction method (QTcI) was below 10 ms, the threshold for regulatory concern. The dose of 90 mg is adequate to represent the high exposure clinical scenario.

Pharmacokinetic properties

The pharmacokinetics of FIRAZYR has been characterized in studies using both intravenous and subcutaneous administration to healthy subjects and patients. The pharmacokinetic profile of FIRAZYR in patients with HAE is similar to that in healthy subjects.

The absolute bioavailability of FIRAZYR following a 30 mg subcutaneous dose is approximately 97%. Following subcutaneous administration of a single 30 mg dose of FIRAZYR to healthy subjects (N=96), a mean (± standard deviation) maximum plasma concentration (Cmax) of 974 ± 280 ng/mL was observed after approximately 0.75 hours. The mean area under the concentration-time curve (AUC0-∞) after a single 30 mg dose was 2165 ± 568 ng·hr/mL, with no evidence of accumulation of icatibant following three 30 mg doses administered 6 hours apart. Following subcutaneous administration, plasma clearance was 245 ± 58 mL/min with a mean elimination half-life of 1.4 ± 0.4 hours and volume of distribution at steady state (Vss) of 29.0 ± 8.7 L.

Icatibant is extensively metabolized by proteolytic enzymes to inactive metabolites that are primarily excreted in the urine, with less than 10% of the dose eliminated as unchanged drug. Icatibant is not degraded by oxidative metabolic pathways, is not an inhibitor of major cytochrome P450 (CYP) isoenzymes (CYP 1A2, 2A6, 2B6, 2C8, 2C9, 2C19, 2D6, 2E1, and 3A4) and is not an inducer of CYP 1A2 and 3A4.

Date of revision of the text

Fertility, pregnancy and lactation

Pregnancy Category C. There are no adequate and well-controlled studies in pregnant women. Icatibant was not teratogenic in rats or rabbits; however, it caused delayed parturition, fetal death, and pre-implantation loss in rats and premature birth, abortion, fetal death, and pre-implantation loss in rabbits. FIRAZYR should be used during pregnancy only if the potential benefit justifies the potential risk to the fetus.

Delayed parturition and fetal death in rats occurred at 0.5 and 2-fold, respectively, the maximum recommended human dose (MRHD) (on an AUC basis at maternal doses of 1 and 3 mg/kg, respectively). Increased pre-implantation loss in rats occurred at 7-fold the MRHD (on an AUC basis at a maternal dose of 10 mg/kg). In rabbits, premature birth and abortion rates increased at a dose that was less than 1/40th the MRHD (on a mg/m² basis at a maternal dose of 0.1 mg/kg). Studies in rabbits also indicated that pre-implantation loss and increased fetal deaths occurred at 13-fold greater than the MRHD (on an AUC basis at a maternal dose of 10 mg/kg).

Nonteratogenic effects: Impairment of pup air-righting reflex and decreased pup hair growth in rats occurred at 7-fold the MRHD (on an AUC basis at a maternal dose of 10 mg/kg).

Qualitative and quantitative composition

FIRAZYR injection is supplied in a prefilled syringe delivering 30 mg icatibant. Each syringe delivers 3 mL solution with a concentration of 10 mg per mL.

FIRAZYR is supplied as a single-use, prefilled syringe for subcutaneous administration. Each syringe delivers 3 mL of a sterile solution of icatibant 30 mg (as icatibant acetate). Each glass syringe has a bromobutyl plunger stopper, which is not made of latex natural rubber.

FIRAZYR is available in cartons containing one single-use, prefilled syringe and one 25 G Luer lock needle. NDC 54092-702-02.

FIRAZYR is also available in a pack containing 3 cartons; each carton contains one single-use, prefilled syringe and one 25 G Luer lock needle. NDC 54092-702-03.

Keep out of the reach of children. Store between 2 -25° C (36 -77° F). Do not freeze. Store in carton until time of administration.

Manufactured for: Shire Orphan Therapies, LLC., 300 Shire Way Lexington, MA 02421. Revised: November2015

Special warnings and precautions for use

Included as part of the PRECAUTIONS section.

Given the potential for airway obstruction during acute laryngeal HAE attacks, patients should be advised to seek medical attention in an appropriate healthcare facility immediately in addition to treatment with FIRAZYR.

See FDA-approved patient labeling (PATIENT INFORMATION and Instructions for Use).

Patients may self-administer FIRAZYR upon recognition of an HAE attack after training under the guidance of a healthcare professional.

Patients with laryngeal symptoms should seek medical attention immediately in an appropriate healthcare facility after administration of FIRAZYR.

Injection site reactions are reported in most patients after administration of FIRAZYR. Other adverse reactions reported after administration of FIRAZYR include pyrexia, increase in transaminases, dizziness, and rash.

Tiredness, drowsiness, and dizziness have been reported following the use of FIRAZYR. Patients should be advised not to drive or use machinery if they feel tired or dizzy.

Two-year studies were conducted in CD1 mice and Wistar rats to assess the carcinogenic potential of FIRAZYR. No evidence of tumorigenicity was observed in mice and rats at icatibant subcutaneous doses up to 15mg/kg/day (twice per week) and 6 mg/kg/day (daily), respectively (approximately 10-fold and 6fold greater than the Maximum Recommended Human Dose on an AUC basis, respectively).

Icatibant tested negative for genotoxicity in the in vitro Ames bacterial reverse mutation test, in vitro Chinese hamster bone marrow chromosome aberration assay, and in vivo mouse micronucleus test.

Daily subcutaneous administration of icatibant to rats and dogs caused ovarian, uterine, and testicular atrophy/degeneration and adverse effects on the mammary and prostate glands. In rats, testicular atrophy, reduced prostate gland secretion, decreased testosterone levels and degenenerate corpora lutea occurred at doses greater than or equal to 3 mg/kg (approximately 5-fold greater than the MRHD in males and 2-fold greater than the MRHD in females on an AUC basis) and a decrease in developing ovarian follicles, mammary gland masculinization, and uterine atrophy occurred at doses greater than or equal to 10 mg/kg (approximately 6-fold greater than MRHD in females on an AUC basis). In dogs, reduced sperm counts and uterine atrophy occurred at doses greater than or equal to 1 mg/kg (approximately 2-fold greater than the MRHD on an AUC basis). Atrophy of the testes and prostate with decreased testosterone levels, decreased ovary size and decreased number of developing follicles occurred at a dose of 10 mg/kg (approximately 30-fold greater than the MRHD in males and 15-fold greater than at the MRHD in females on an AUC basis).

In contrast to the effects of daily icatibant administration, toxicity to the ovary, uterus, testis, mammary gland, and prostate did not occur in dogs treated twice a week for 9 months. AUC exposures from a dose of 3 mg/kg in these dogs were 5-and 3-fold the MRHD exposures in men and women, respectively. Sperm counts and testosterone remained unaffected over the course of the study in male dogs dosed twice a week.

Reproduction studies in male mice and rats with daily administration of icatibant found no effects on fertility or reproductive performance with intravenous doses up 81 mg/kg (approximately 5-fold greater than the MRHD on a mg/m² basis) or subcutaneous doses up to 10 mg/kg (approximately 11-fold greater than the MRHD on an AUC basis), respectively.

Pregnancy Category C. There are no adequate and well-controlled studies in pregnant women. Icatibant was not teratogenic in rats or rabbits; however, it caused delayed parturition, fetal death, and pre-implantation loss in rats and premature birth, abortion, fetal death, and pre-implantation loss in rabbits. FIRAZYR should be used during pregnancy only if the potential benefit justifies the potential risk to the fetus.

Delayed parturition and fetal death in rats occurred at 0.5 and 2-fold, respectively, the maximum recommended human dose (MRHD) (on an AUC basis at maternal doses of 1 and 3 mg/kg, respectively). Increased pre-implantation loss in rats occurred at 7-fold the MRHD (on an AUC basis at a maternal dose of 10 mg/kg). In rabbits, premature birth and abortion rates increased at a dose that was less than 1/40th the MRHD (on a mg/m² basis at a maternal dose of 0.1 mg/kg). Studies in rabbits also indicated that pre-implantation loss and increased fetal deaths occurred at 13-fold greater than the MRHD (on an AUC basis at a maternal dose of 10 mg/kg).

Nonteratogenic effects: Impairment of pup air-righting reflex and decreased pup hair growth in rats occurred at 7-fold the MRHD (on an AUC basis at a maternal dose of 10 mg/kg).

There are no human studies that have investigated the effects of FIRAZYR on preterm labor or labor at term; however, animal studies showed that icatibant causes delayed parturition and associated fetal death in rats and premature birth and abortion in rabbits. Delayed parturition occurred in rats at 0.5-fold times the MRHD (on an AUC basis at a maternal dose of 1 mg/kg).

Because many drugs are excreted in human milk, caution should be exercised when FIRAZYR is administered to a nursing woman. Icatibant is excreted into the milk of lactating rats.

Safety and effectiveness in pediatric patients below the age of 18 years have not been established.

Subcutaneous daily administration of icatibant to young rats during the juvenile period of development (postnatal days 22-70) delayed the sexual maturation of male reproductive tissues (atrophy of testes and epididymides) at exposures approximating one-third or greater the MRHD on a mg/m² basis. Impaired fertility and reproductive performance were also observed in male rats at the end of the postnatal treatment period at exposures approximating the MRHD or greater on a mg/m² basis. No effects were observed in females at exposures approximating 3-fold the MRHD on a mg/m² basis. The observed tissue findings in males were consistent with those seen in sexually mature rats and dogs and are attributed to antagonism of the bradykinin B2 receptor and subsequent effects on gonadotropins. The observed effects may be a consequence of daily icatibant administration. Toxicity to the testis did not occur in dogs treated twice a week for 9 months.

Clinical studies of FIRAZYR did not include sufficient numbers of subjects aged 65 and over to determine whether they respond differently from younger subjects. Elderly patients are likely to have increased systemic exposure to FIRAZYR compared to younger (18-45 years) patients. Since other reported clinical experience has not identified differences in efficacy and safety between elderly and younger patients, no dose adjustment is recommended.

FIRAZYR was studied in patients with mild to moderate (Child Pugh scores of 5 to 8) hepatic impairment. No change in systemic exposure is noted in these patient populations. No dose adjustment is required in patients with hepatic impairment.

Although a formal renal impairment study has not been conducted, 10 of 37 patients treated with FIRAZYR had hepatorenal syndrome with glomerular filtration rate (GFR) below 60 mL/min. FIRAZYR is cleared non-renally and hence it is not expected to show any change in systemic exposure in patients with impaired renal function. No dose adjustment is required in patients with renal impairment.

Dosage (Posology) and method of administration

The recommended dose of FIRAZYR is 30 mg administered by subcutaneous (SC) injection in the abdominal area. Additional doses may be administered at intervals of at least 6 hours if response is inadequate or if symptoms recur. No more than 3 doses may be administered in any 24 hour period.

FIRAZYR should be inspected visually for particulate matter and discoloration prior to administration. The drug solution should be clear and colorless. Do not administer if the product contains particulates or is discolored.

Attach the provided 25 gauge needle to the syringe hub and screw on securely. Do not use a different needle. Disinfect the injection site and administer FIRAZYR by subcutaneous injection over at least 30 seconds.

Patients may self-administer FIRAZYR upon recognition of symptoms of an HAE attack after training under the guidance of a healthcare professional.

Interaction with other medicinal products and other forms of interaction

Formal drug-drug interaction studies were not conducted with FIRAZYR. Icatibant metabolism is not mediated by CYP450 enzymes. In vitro study did not show any significant inhibition and/or induction of drug metabolizing CYP450 enzymes; therefore, metabolic drug interactions between FIRAZYR and CYP450 substrates, inhibitors and inducers are not expected.