Healthcare professionals should train patients in the proper technique for self-administering subcutaneous injections using the prefilled pen or syringe. Patients should be advised to rotate sites for subcutaneous injections. The usual sites for subcutaneous injections are abdomen, back of the upper arm, and thigh.
Each PLEGRIDY pen and syringe is provided with the needle pre-attached. Prefilled pens and syringes are for a single dose only and should be discarded after use.
2.3 Premedication for Flu-like Symptoms
Prophylactic and concurrent use of analgesics and/or antipyretics may prevent or ameliorate flu-like symptoms sometimes experienced during treatment with PLEGRIDY.
3 DOSAGE FORMS AND STRENGTHS
Injection: 125 micrograms of PLEGRIDY per 0.5 mL of solution in a single-dose prefilled pen
Injection: Starter Pack containing 63 micrograms per 0.5 mL of solution in a single-dose prefilled pen and 94 micrograms per 0.5 mL solution in a single-dose prefilled pen
Injection: 125 micrograms of PLEGRIDY per 0.5 mL of solution in a single-dose prefilled syringe
Injection: Starter Pack containing 63 micrograms per 0.5 mL of solution in a single-dose prefilled syringe and 94 micrograms per 0.5 mL of solution in a single-dose prefilled syringe
PLEGRIDY is contraindicated in patients with a history of hypersensitivity to natural or recombinant interferon beta or peginterferon, or any other component of the formulation [see Warnings and Precautions (5.4)].
5 WARNINGS AND PRECAUTIONS
5.1 Hepatic Injury
Severe hepatic injury, including hepatitis, autoimmune hepatitis, and rare cases of severe hepatic failure, have been reported with interferon beta. Asymptomatic elevation of hepatic transaminases has also been reported, and in some patients has recurred upon rechallenge with interferon beta.
Elevations in hepatic enzymes and hepatic injury have been observed with the use of PLEGRIDY in clinical studies. The incidence of increases in hepatic transaminases was greater in patients taking PLEGRIDY than in those taking placebo. The incidence of elevations of alanine aminotransferase above 5 times the upper limit of normal was 1% in placebo-treated patients and 2% in PLEGRIDY-treated patients. The incidence of elevations of aspartate aminotransferase above 5 times the upper limit of normal was less than 1% in placebo-treated patients and less than 1% in PLEGRIDY-treated patients. Elevations of serum hepatic transaminases combined with elevated bilirubin occurred in 2 patients. Both cases resolved following discontinuation of PLEGRIDY.
Monitor patients for signs and symptoms of hepatic injury.
5.2 Depression and Suicide
Depression, suicidal ideation, and suicide occur more frequently in patients receiving interferon beta than in patients receiving placebo.
In clinical studies, the overall incidence of adverse events related to depression and suicidal ideation in multiple sclerosis patients was 8% in both the PLEGRIDY and placebo groups. The incidence of serious events related to depression and suicidal ideation was similar and less than 1% in both groups.
Advise patients to report immediately any symptom of depression or suicidal ideation to their healthcare provider. If a patient develops depression or other severe psychiatric symptoms, consider stopping treatment with PLEGRIDY.
Seizures are associated with the use of interferon beta.
The incidence of seizures in multiple sclerosis clinical studies was less than 1% in patients receiving PLEGRIDY and placebo.
Exercise caution when administering PLEGRIDY to patients with a seizure disorder.
5.4 Anaphylaxis and Other Allergic Reactions
Anaphylaxis and other serious allergic reactions are rare complications of treatment with interferon beta.
Less than 1% of PLEGRIDY-treated patients experienced a serious allergic reaction such as angioedema or urticaria. Those who did have serious allergic reactions recovered promptly after treatment with antihistamines or corticosteroids.
Discontinue PLEGRIDY if a serious allergic reaction occurs.
5.5 Injection Site Reactions
Injection site reactions, including injection site necrosis, can occur with the use of subcutaneous interferon beta.
In clinical studies, the incidence of injection site reactions (e.g., injection site erythema, pain, pruritus, or edema) was 66% in the PLEGRIDY group and 11% in the placebo group; the incidence of severe injection site reactions was 3% in the PLEGRIDY group and 0% in the placebo group. One patient out of 1468 patients who received PLEGRIDY in clinical studies experienced injection site necrosis. The injury resolved with standard medical treatment.
Decisions to discontinue therapy following necrosis at a single injection site should be based on the extent of the necrosis. For patients who continue therapy with PLEGRIDY after injection site necrosis has occurred, avoid administration of PLEGRIDY near the affected area until it is fully healed. If multiple lesions occur, discontinue PLEGRIDY until healing occurs.
5.6 Congestive Heart Failure
Congestive heart failure, cardiomyopathy, and cardiomyopathy with congestive heart failure occur in patients receiving interferon beta.
In clinical studies, the incidence of cardiovascular events was 7% in both PLEGRIDY and placebo treatment groups. No serious cardiovascular events were reported in the PLEGRIDY group.
Monitor patients with significant cardiac disease for worsening of their cardiac condition during initiation and continuation of treatment with PLEGRIDY.
5.7 Decreased Peripheral Blood Counts
Interferon beta can cause decreased peripheral blood counts in all cell lines, including rare instances of pancytopenia and severe thrombocytopenia.
In clinical studies, decreases in white blood cell counts below 3.0 x 109/L occurred in 7% of patients receiving PLEGRIDY and in 1% receiving placebo. There is no apparent association between decreases in white blood cell counts and an increased risk of infections or serious infections. The incidence of clinically significant decreases in lymphocyte counts (below 0.5 x 109/L), neutrophil counts (below 1.0 x 109/L), and platelet counts (below 100 x 109/L) were all less than 1% and similar in both placebo and PLEGRIDY groups. Two serious cases were reported in patients treated with PLEGRIDY: one patient (less than 1%) experienced severe thrombocytopenia (defined as a platelet count less than or equal to 10 x 109/L), and another patient (less than 1%) experienced severe neutropenia (defined as a neutrophil count less than or equal to 0.5 x 109/L). In both patients, cell counts recovered after discontinuation of PLEGRIDY. Compared to placebo, there were no significant differences in red blood cell counts in patients treated with PLEGRIDY.
Monitor patients for infections, bleeding, and symptoms of anemia. Monitor complete blood cell counts, differential white blood cell counts, and platelet counts during treatment with PLEGRIDY. Patients with myelosuppression may require more intensive monitoring of blood cell counts.
5.8 Thrombotic Microangiopathy
Cases of thrombotic microangiopathy (TMA), including thrombotic thrombocytopenic purpura and hemolytic uremic syndrome, some fatal, have been reported with interferon beta products. Cases have been reported several weeks to years after starting interferon beta products. Discontinue PLEGRIDY if clinical symptoms and laboratory findings consistent with TMA occur, and manage as clinically indicated.
5.9 Autoimmune Disorders
Autoimmune disorders of multiple target organs including idiopathic thrombocytopenia, hyper- and hypothyroidism, and autoimmune hepatitis have been reported with interferon beta.
In clinical studies, the incidence of autoimmune disorders was less than 1% in both PLEGRIDY and placebo treatment groups.
If patients develop a new autoimmune disorder, consider stopping PLEGRIDY.
6 ADVERSE REACTIONS
The following serious adverse reactions are discussed in more detail in other sections of labeling:
Hepatic Injury [see Warnings and Precautions (5.1)]
Depression and Suicide [see Warnings and Precautions (5.2)]
Seizures [see Warnings and Precautions (5.3)]
Anaphylaxis and Other Allergic Reactions [see Warnings and Precautions (5.4)]
Injection Site Reactions [see Warnings and Precautions (5.5)]
Congestive Heart Failure [see Warnings and Precautions (5.6)]
Decreased Peripheral Blood Counts [see Warnings and Precautions (5.7)]
Thrombotic Microangiopathy [see Warnings and Precautions (5.8)]
Autoimmune Disorders [see Warnings and Precautions (5.9)]
6.1 Clinical Trials Experience
Because clinical trials are conducted under widely varying conditions, adverse reaction rates observed in the clinical trials of PLEGRIDY cannot be directly compared to rates in clinical trials of other drugs and may not reflect the rates observed in practice.
In clinical studies (Study 1 and Study 2), a total of 1468 patients with relapsing multiple sclerosis received PLEGRIDY for up to 177 weeks (41 months), with an overall exposure equivalent to 1932 person-years. A total of 1093 patients received at least 1 year, and 415 patients at least 2 years of treatment with PLEGRIDY. A total of 512 and 500 patients, respectively, received PLEGRIDY 125 micrograms every 14 days or every 28 days during the placebo-controlled phase of Study 1 (year 1). The experience in year 2 of Study 1 and in the 2-year safety extension study (Study 2) was consistent with the experience in the 1-year placebo-controlled phase of Study 1.
In the placebo-controlled phase of Study 1, the most common adverse drug reactions for PLEGRIDY 125 micrograms subcutaneously every 14 days were injection site erythema, influenza-like illness, pyrexia, headache, myalgia, chills, injection site pain, asthenia, injection site pruritus, and arthralgia (all had incidence more than 10% and at least 2% more than placebo). The most commonly reported adverse event leading to discontinuation in patients treated with PLEGRIDY 125 micrograms subcutaneously every 14 days was influenza-like illness (in less than 1% of patients).
Table 2 summarizes adverse reactions reported over 48 weeks from patients treated in the placebo-controlled phase of Study 1 who received subcutaneous PLEGRIDY 125 micrograms (n=512), or placebo (n=500), every 14 days.
Table 2: Adverse reactions in the 48-week placebo-controlled phase of Study 1 with an incidence 2% higher for PLEGRIDY than for placebo
For therapeutic proteins, there is a potential for immunogenicity. In Study 1, fewer than 1% of patients treated with PLEGRIDY every 14 days for 1 year developed neutralizing antibodies. Approximately 7% of PLEGRIDY-treated patients developed antibodies to PEG.
The detection of antibody formation is highly dependent on the sensitivity and specificity of the assay. Additionally, the observed incidence of antibody (including neutralizing antibody) positivity in an assay may be influenced by several factors including assay methodology, sample handling, timing of sample collection, concomitant medications, and underlying disease. For these reasons, comparison of the incidence of antibodies to PLEGRIDY with the incidence of antibodies to other products may be misleading.
Influenza-like illness was experienced by 47% of patients receiving PLEGRIDY 125 micrograms every 14 days and 13% of patients receiving placebo. Fewer than 1% of PLEGRIDY-treated patients in Study 1 discontinued treatment due to flu-like symptoms.
8 USE IN SPECIFIC POPULATIONS
Pregnancy Category C
There are no adequate and well-controlled studies in pregnant women. PLEGRIDY should be used during pregnancy only if the potential benefit justifies the potential risk to the fetus.
PLEGRIDY has not been tested for developmental toxicity in pregnant animals. In monkeys given interferon beta by subcutaneous injection every other day during early pregnancy, no teratogenic or other adverse effects on fetal development were observed. Abortifacient activity was evident following 3 to 5 doses.
8.3 Nursing Mothers
It is not known whether this drug is excreted in human milk. Because many drugs are excreted in human milk, caution should be exercised when PLEGRIDY is administered to a nursing woman.
8.4 Pediatric Use
Safety and effectiveness in pediatric patients have not been established.
8.5 Geriatric Use
Safety and effectiveness in geriatric patients have not been established.
8.6 Renal Impairment
Monitor for adverse reactions due to increased drug exposure in patients with severe renal impairment [see Clinical Pharmacology (12.3)].
PLEGRIDY (peginterferon beta-1a) is an interferon beta-1a to which a single, linear 20,000 dalton (Da) methoxy poly(ethyleneglycol)-O-2-methylpropionaldehyde molecule is covalently attached to the alpha amino group of the N-terminal amino acid residue.
The interferon beta-1a portion of PLEGRIDY is produced as a glycosylated protein using genetically-engineered Chinese hamster ovary cells into which the human interferon beta gene has been introduced. The amino acid sequence of the recombinant interferon beta-1a is identical to that of the human interferon beta counterpart. The molecular mass of PLEGRIDY is approximately 44,000 Da, consistent with the mass of the protein (approximately 20,000 Da), the carbohydrate moieties (approximately 2,500 Da), and the attached poly(ethylene glycol). However, because of the extended and flexible nature of the attached poly(ethylene glycol) chain, the apparent mass of PLEGRIDY in solution is greater than 300,000 Da. The more than 10-fold increase in apparent mass of PLEGRIDY compared to interferon beta-1a has been shown to contribute to the reduced clearance in vivo.
PLEGRIDY 125 micrograms contains 125 micrograms of interferon beta-1a plus 125 micrograms of poly(ethylene glycol). Using the World Health Organization International Standard for interferon beta, PLEGRIDY has a specific antiviral activity of approximately 100 million International Units (MIU) per mg of protein as determined using an in vitro cytopathic effect assay. PLEGRIDY 125 micrograms contains approximately 12 MIU of antiviral activity. PLEGRIDY contains no preservative.
11.1 PLEGRIDY PEN Single-Dose Prefilled Pen
PLEGRIDY PEN is composed of an autoinjector that surrounds a prefilled glass syringe containing 0.5 mL of a sterile solution in water for injection of 63, 94, or 125 micrograms of peginterferon beta-1a, 15.8 mg of L-arginine HCl, 0.79 mg of sodium acetate trihydrate, 0.25 mg of glacial acetic acid, and 0.025 mg of polysorbate 20. The pH is approximately 4.8.
11.2 PLEGRIDY Single-Dose Prefilled Syringe
A prefilled syringe of PLEGRIDY for subcutaneous injection contains 0.5 mL of a sterile solution in water for injection of 63, 94, or 125 micrograms of peginterferon beta-1a, 15.8 mg of L-arginine HCl, 0.79 mg of sodium acetate trihydrate, 0.25 mg of glacial acetic acid, and 0.025 mg of polysorbate 20. The pH is approximately 4.8.
12 CLINICAL PHARMACOLOGY
12.1 Mechanism of Action
The mechanism by which PLEGRIDY exerts its effects in patients with multiple sclerosis is unknown.
There is no biochemical or physiologic effect known to relate directly to the clinical effect of PLEGRIDY.
After single-dose or multiple-dose subcutaneous administration of PLEGRIDY to healthy subjects, serum PLEGRIDY peak concentration (Cmax) and total exposure over time (area under the curve, or AUC) increased in proportion to doses from 63 to 188 micrograms. PLEGRIDY did not accumulate in the serum after multiple doses of 125 micrograms every 14 days. Pharmacokinetic parameters for PLEGRIDY, including Cmax and AUC, did not differ significantly between healthy volunteers and multiple sclerosis patients or between single-dose and multiple-dose administrations. However, the coefficient of variation between individual patients for AUC, Cmax, and half-life was high (41% to 68%, 74% to 89%, and 45% to 93%, respectively).
After 125 microgram subcutaneous doses of PLEGRIDY in multiple sclerosis patients, the maximum concentration occurred between 1 and 1.5 days, the mean Cmax was 280 pg/mL, and the AUC over the 14 day dosing interval was 34.8 ng.hr/mL.
In multiple sclerosis patients taking 125 microgram subcutaneous doses of PLEGRIDY every 14 days, the estimated volume of distribution was 481 liters.
Metabolism and Elimination
Clearance mechanisms for PLEGRIDY include catabolism and excretion. The major pathway of elimination is renal. The half-life is approximately 78 hours in multiple sclerosis patients. The mean steady state clearance of PLEGRIDY is approximately 4.1 L/hr. PLEGRIDY is not extensively metabolized in the liver.
Body weight, gender, and age do not require dosage adjustment.
Renal impairment can increase the Cmax and AUC for PLEGRIDY. Results of a pharmacokinetic study in patients with mild, moderate, and severe renal impairment (creatinine clearance 50 to 80, 30 to 50, and less than 30 mL/minute, respectively) showed increases above normal for Cmax of 27%, 26%, and 42%, and for AUC, increases of 30%, 40%, and 53%. The half-life was 53, 49, and 82 hours in patients with mild, moderate, and severe renal impairment, respectively, compared to 54 hours in normal subjects.
In the same study, subjects with end stage renal disease requiring hemodialysis two or three times weekly had AUC and Cmax of PLEGRIDY values that were similar to those of normal controls. Each hemodialysis session removed approximately 24% of circulating PLEGRIDY from the systemic circulation [see Use in Specific Populations (8.6)].
13 NONCLINICAL TOXICOLOGY
13.1 Carcinogenesis, Mutagenesis, Impairment of Fertility
The carcinogenic potential of PLEGRIDY has not been tested in animals.
PLEGRIDY was not mutagenic when tested in an in vitro bacterial reverse mutation (Ames) test and was not clastogenic in an in vitro assay in human lymphocytes.
Impairment of Fertility
In monkeys administered interferon beta by subcutaneous injection over the course of one menstrual cycle, menstrual irregularities, anovulation, and decreased serum progesterone levels were observed. These effects were reversible after discontinuation of drug.
14 CLINICAL STUDIES
The efficacy of PLEGRIDY was demonstrated in the randomized, double-blind, and placebo-controlled phase (year 1) of Study 1. The trial compared clinical and MRI outcomes at 48 weeks in patients who received PLEGRIDY 125 micrograms (n=512) or placebo (n=500) by the subcutaneous route, once every 14 days.
Study 1 enrolled patients who had a baseline Expanded Disability Status Scale (EDSS) score from 0 to 5, who had experienced at least 2 relapses within the previous three years, and had experienced at least 1 relapse in the previous year. The trial excluded patients with progressive forms of multiple sclerosis. The mean age of the study population was 37 years, the mean disease duration was 3.6 years, and the mean EDSS score at baseline was 2.46. The majority of the patients were women (71%).
The trial scheduled neurological evaluations at baseline, every 12 weeks, and at the time of a suspected relapse. Brain MRI evaluations were scheduled at baseline, week 24, and week 48.
The primary outcome was the annualized relapse rate over 1 year. Secondary outcomes included the proportion of patients relapsing, number of new or newly enlarging T2 hyperintense lesions, and time to confirmed disability progression. Confirmed disability progression was defined as follows: if the baseline EDSS score was 0, a sustained 12-week increase in EDSS score of 1.5 points was required; if the baseline EDSS score was greater than 0, a sustained 12-week increase in EDSS score of 1 point was required. Table 3 and Figure 1 show the results of Study 1.
Table 3: Clinical and MRI Results of Study 1